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This prospective clinical study evaluated the survival of indirect, posterior fiber-reinforced composite fixed dental prosthesis (FRC FDP). Between June-1999 and June- 2000, 58 patients received 65 FCR FDPs made of unidirectional E-glass fibers (Vectris) veneered with resin composite (Signum) that were adhesively cemented (Variolink II). The evaluation protocol involved technical (chipping, debonding or fracture of tooth/restoration) and biological failures (caries, endodontic complications). Altogether, 6 technical failures were observed after a mean observation time of 180 months (survival rate: 89.2%, Kaplan-Meier) in the form of fractures (n=2) and partial debondings (n=4). All defective restorations were repaired or recemented. Secondary caries occurred in one patient after 11 years. The 3-unit posterior FRC FDPs showed good clinical survival rate up to 15 years of clinical function. Limited numbers of experienced failures were due to mainly debonding followed by fracture of the veneering composite.g composite., (Copyright© 2024 Dennis Barber Ltd.)

Aim: To compare the tensile strength, dislodgement forces, marginal gap and failure types between digitally fabricated zirconia root copings and conventionally manufactured cast gold root copings., Methods: Extracted human teeth (N=30) were prepared for the root copings and randomly divided into 2 groups: (1)zirconia root copings(ZC) and gold root copings(GC). The specimens were tested for tensile bond strength and dislodgement forces in a universal testing machine and the types of the coping failures modes were analyzed. In addition, the marginal gap was measured. Data were analyzed using one-way ANOVA and Pearson correlation test., Results: Mean tensile bond strength in the total horizontal adhesive area for ZC group was 7.5±2.8MPa and for GC group 10.5±4.8 MPa(p⟩0.05). The mean dislodgement forces for the ZC and GC groups were 242±107N and 311±118N, respectively and with no significant differences between the groups (p=0.12). The mean vertical marginal gap in the ZC group amounted to 27±11.05μm, while in the GC group it was 35.33±10.49μm, showing no statistically significant difference between the two groups (p=0.058). Mixed failure modes were more common (93%) in both groups., Conclusions: In terms of all tested parameters, the zirconia root copings were comparable to the gold copings., (Copyright© 2024 Dennis Barber Ltd.)

Background and Objectives: Contemporary dentistry focuses on more conservative treatment options such as endocrown restorations and application of dental materials with higher resemblance to tooth structure. Polyether ether ketone (PEEK) polymer is a material used for the fabrication of endocrowns. This study aimed to compare the post-fatigue resistance (PFR) of mandibular first molars restored with PEEK and lithium disilicate (LS 2 ) endocrown restorations. Materials and Methods: This in vitro, experimental study was conducted on 20 human mandibular first molars with similar dimensions. The teeth were prepared for endocrown restoration and were assigned to two groups ( n  = 10) of PEEK and LS 2 endocrowns. After fabrication by the computer-aided design and computer-aided manufacturing (CAD-CAM) technique, the restorations were cemented with resin cement. Next, the teeth underwent 15,000 thermal cycles followed by cyclic loading with 600,000 cycles of compressive force (100 N, 4 Hz) and were then subjected to compressive load application in a universal testing machine. The load causing endocrown failure was recorded as the PFR of the respective restoration. The failure mode was also inspected under a light microscope. Data were analyzed by the independent t -test and also chi-square, Mann-Whitney, and Fisher's exact tests ( α  < 0.05). Results: The teeth with PEEK endocrowns showed significantly higher PFR than those with LS 2 endocrowns. Irreparable fractures were dominant in both groups. Conclusion: PEEK may serve as a suitable alternative to LS 2 for the fabrication of endocrown restorations., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Mehrak Amjadi et al.)

Purpose: To investigate the effect of BruxZir Steel treatment on the fracture resistance of zirconia threeunit bridges prepared using 5Y-PSZ-based zirconia blanks., Materials and Methods: Three-unit zirconia bridges were milled using CAD/CAM from homogeneous bisque zirconia blanks (5Y-PSZ-based) supplied by various manufacturers and sintered. Fracture resistance was analyzed with dynamic loading. For each zirconia blank, the fracture resistance of the sintered test restoration (cementation surface treated with BruxZir Steel) was compared to the sintered control restoration (untreated cementation surface). Finite element analysis (FEA) was used to analyze the stress distribution on the three-unit bridge under an axial load., Results: The fracture resistance of the test restorations was significantly higher than that of the control restorations for all manufacturers considered in this study (P < .05). Furthermore, the restoration made of BruxZir Esthetic treated with BruxZir Steel had the highest fracture resistance compared to the other restorations. In addition, the three-unit bridge restorations prepared from 5Y-PSZ-based zirconia blanks exhibited differences in grain size and fracture toughness depending on the presence or absence of BruxZir Steel treatment. The locations of high stresses under FEA correlated well with the fracture locations in the corresponding experimental test. FEA also demonstrated the improved performance of the BruxZir Steel-treated sample compared to the control., Conclusions: The fracture resistance of 5Y-PSZ-based BruxZir Steel-treated three-unit bridges was significantly higher (min = 30%, max = 198%) than the control.

Purpose: To investigate the influence of milling parameters on the durability and fracture force of resinbased composite crowns during in vitro aging simulation., Materials and Methods: Identical molar crowns (n = 8 per group) were milled from resin-based composite crowns (Grandio, VOCO Dental) with different processing speeds (soft, normal, fast) or levels of detail (very high, high, low) from 98-mm disks. One group was milled wet to investigate the influence of cooling. The influence of polishing was tested in two groups. All crowns were adhesively bonded on standardized resin-based composite molars. Aging was performed with thermal cycling and mechanical loading (2 × 3,000 × 5°C/55°C, 2 minutes, H20 dist., 1.2 × 106 force at 50 N). Fracture forces were determined (v = 1 mm/minute, Z010, Zwick Roell)., Results: For statistical analysis, Pearson correlation, one-way ANOVA, and Bonferroni post hoc tests were used (α = .05). All crowns survived thermal cycling and mechanical loading (TCML) without any failures. The fracture values varied between 1,237.3 ± 326.7 N and 3,308.6 ± 655.8 N. Significant (P < .001) differences between the individual manufacturing approaches were detected. Failure was categorized as a fracture of the crown and partial loosening of the crown. No different failure pattern was observed between the tested systems., Conclusions: A medium level of detail seems to be ideal to achieve the highest fracture forces. No relationship existed between machine speed and fracture force. Fracture force was not affected by wet grinding. In individual cases, polishing reduced crown fracture values due to reduced wall thickness.

Purpose: To assess wear, fatigue, and fracture resistance of different CAD/CAM onlays milled from monolithic zirconia (ZR), hybrid ceramic (EN), and lithium disilicate (LS) when used as abutments for removable partial denture frameworks fabricated from acetal resin (AR) or cobalt-chromium (Co-Cr)., Materials and Methods: Standard onlays and RPD framework were designed and milled using CAD/CAM. Onlays were cemented with resin cement to identical teeth models. The RPD's occlusal rest surface and the ceramic onlays' rest seats were both 3D scanned before and aPer 750,000 mechanical load cycles (50 N) and 8,000 thermal cycles (5° to 55°C) in a chewing simulator. The volumetric loss was measured using 3D-image processing software, and the failure of the samples was detected using a stereomicroscope. The fracture resistance was tested by loading to failure in a universal testing machine. The fatigue failure results were analyzed with Fisher exact probability test, and the wear and fracture resistance data were analyzed using twoway ANOVA and Bonferroni post-hoc test (P < .05)., Results: A significant difference (P < .05) was found between the tested experimental groups in wear, fatigue, and fracture resistance. Zr/Co-Cr combinations exhibited the least wear and the highest fatigue and fracture resistance (P < .05), while the highest wear and least fatigue and fracture resistance were recorded for the EN/AR group (P < .05)., Conclusions: Zr onlays demonstrated a conserva&#43;ve treatment option with superior mechanical behavior when used as an onlay abutment, regardless of the RPD framework material used. The AR framework is not recommended in the posterior region for removable partial dentures.

Purpose: To investigate the medium-term survival of Dalbo-Rotex retention elements, identify potential risk factors for complication or loss, and consider economic factors., Materials and Methods: Patients treated with Dalbo-Rotex retention elements in a university setting were retrospectively identified and examined. Clinical data comprised assessments of the dental, periodontal, endodontic, and prosthetic situation, including radiographic analysis. Patient satisfaction was quantified with visual analog scale questionnaires. Five-year Kaplan-Meier plots for relative survival and success rates were calculated., Results: The 45 included patients had a total of 76 Dalbo-Rotex retention elements. Of these, 12 Dalbo-Rotex elements failed and complications occurred in 42.1% of elements, equating to a survival rate of 84.2% and a success rate of 47.4% after a mean observation period of 49.2 ± 52.4 months (range: 6 to 219 months). The 5-year cumulative survival and success rates were 62.4% (95% CI: 44.0% to 88.4%) and 35.6% (95% CI: 23.8% to 53.2%), respectively. Patients' self-assessment of prosthesis retention was rated at 82 (IQR 40 to 92.2) with low pain perception at 4.5 (IQR 0 to 30). Probing pocket depth levels were significantly reduced in patients adhering to a regular recall interval compared with those with longer intervals., Conclusions: Chairside Dalbo-Rotex retention elements are a straightforward chairside method for prosthesis retention that achieve good survival over medium-term follow-ups with high patient satisfaction. This technique is therefore a viable alternative to cast post copings and can be particularly valuable for patients with limited financial resources.

Purpose: This systematic review (SR) aimed to investigate whether the presence of a cantilever affects the results of implant treatment for partial edentulism, including an analysis of the anterior and posterior regions of the dental arches., Methods: An electronic search was performed, and original articles published between 1995 and November 2023 were included. The outcomes were the implant survival rate, patient satisfaction, occurrence of mechanical complications, and marginal bone loss around the implants. Two SR members independently examined the validity of the studies, extracted evidence from the included studies, and performed risk of bias assessment, comprehensive evidence evaluation, and meta-analysis., Results: Nine studies met our inclusion criteria. Implant survival rate tended to be lower in the cantilever group, and marginal bone loss tended to be higher in the cantilever group; however, there was no significant difference. There was no significant difference in patient satisfaction based on the presence or absence of a cantilever. Moreover, the incidence of mechanical complications was significantly higher in the cantilever group. According to the analysis of anterior and posterior regions, implant survival rate tended to be lower in the cantilever group of the posterior region, and marginal bone loss around the implants tended to be higher in the cantilever group of the anterior region., Conclusion: Implant-supported fixed prostheses with cantilevers did not negatively affect implant survival rate, marginal bone loss, or patient satisfaction. However, the incidence of mechanical complications significantly increased in the cantilever group., Competing Interests: Declarations. Consent for publication: Not applicable. Competing interests: The authors declare that they have no competing interests., (© 2024. The Author(s).)

Purpose: To retrospectively evaluate the influence of mesiodistal intra-coronal cantilever width of implant-supported single crowns on the implant and restoration complication-free survival rate and the peri-implant soft and hard tissues., Materials and Methods: A total of 142 patients with 179 implants in the posterior region were evaluated. The implants were divided into three groups according to intra-coronal cantilever width (Group 1, ≤ 1 mm; Group 2, 1 mm intra-coronal cantilever width 2 mm; Group 3, ≥ 2 mm). Marginal bone loss, complications and clinical parameters were used to evaluate the influence of intra-coronal cantilever width on implant-supported single crowns., Results: Group 1 included 95 implants, Group 2 was composed of 27 implants and Group 3 comprised 57 implants. A univariate Cox proportional hazards model, assessing implant complication-free survival, indicated a higher complication rate for Group 3 compared to Group 1 (P = 0.009). Furthermore, the marginal bone loss on the cantilever side over the short-term and medium- to long-term follow-up period indicated that intra-coronal cantilever width ≥ 2 mm may be considered a risk factor. From a clinical perspective, compared with Group 3, Groups 1 and 2 exhibited lower incidence rates of bleeding on probing during the medium- to long-term follow-up period (P = 0.003)., Conclusions: Despite its limitations, the present study shows that posterior single implant crowns with mesiodistal intra-coronal cantilevers equal to or higher than 2 mm will present greater marginal bone loss, complications and tissue inflammation.

Purpose: Zygomatic implants are considered one of the last options for the rehabilitation of severe maxillary atrophy when standard implants cannot be placed. They offer several advantages but can also present complications. This study aimed to investigate the long-term clinical and radiographic outcomes of zygomatic implant placement., Materials and Methods: A retrospective chart review was conducted, and the inclusion criteria consisted of patients previously treated with zygomatic implants who had Class V or VI maxillary bone atrophy according to Cawood and Howell, and with a minimum follow-up period of 2 years after prosthetic loading. Outcome measures included implant and prosthesis survival rate, biological and biomechanical complications, and Lund-Mackay staging score before and after implant placement., Results: The study included 78 patients who received a total of 274 zygomatic implants. The mean follow-up period was 90.4 ± 26.0 months. Seventeen implant failures occurred, resulting in a survival rate of 93.8%, with a statistically significant negative correlation with smoking habits (P = 0.049), anchorage to the two zygomatic bone cortices (bicorticality) (P 0.001) and soft tissue complications (P 0.001). The prosthetic success rate was 92.3%. A statistically significant increase in maxillary sinus radiopacity was recorded when comparing the situation before and after surgery (P 0.001), and the intrasinus pathway had a statistically significant influence on that increase (P = 0.003)., Conclusions: Zygomatic implants utilised for rehabilitating patients with severe maxillary atrophy have shown favourable outcomes. Nonetheless, owing to potential complications, strict case selection is necessary, combined with regular recall visits and proper oral hygiene maintenance. Furthermore, this type of surgery necessitates specialised training and expertise on the part of the practitioner.

Purpose: There is a scarcity of data regarding the long-term follow-up of dental implants placed in grafted or non-grafted sites. The aim was to systematically review clinical studies which, compared the implant survival rate (ISR) after at least 10 years for dental implants placed in grafted and non-grafted sites., Materials and Methods: The focused question addressed was: 'Is there a difference in the ISR of dental implants placed in grafted and non-grafted sites for at least a decade?' The inclusion criteria were: (a) clinical studies, (b) studies on patients who had undergone dental implant therapy, (c) studies with at least 10 years follow-up, and (d) studies that compared the clinical and radiographic status around implants placed in grafted and non-grafted sites. Indexed databases (PubMed/Medline, Scopus, EMBASE, OVID, ISI Web of Knowledge, and Google Scholar) were searched without time and language restrictions up to and including December 2020 using different keywords. The literature search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The risk of bias was assessed, and the pattern of the present systematic review was customised to summarise pertinent information., Results: The initial search yielded 412 studies through electronic database searching. An additional 30 studies were identified through manual searching of full texts of studies. In total, three studies were included and processed for data extraction. In these studies, the number of participants ranged between 34 and 96 individuals. The mean age ranged between 47.2 and 67.6 years. The reported ISR ranged between 91.6% and 100%. All studies had a low risk of bias. Due to the high heterogeneity among the studies included, a meta-analysis could not be done. Prior sample-size estimation was done in none of the studies., Conclusion: Dental implants placed in grafted and non-grafted sites demonstrate similar ISR for at least a decade. However, further well-designed and power-adjusted studies are needed.

Objective: The objective of this randomized controlled clinical trial (RCT) was to compare the frequency of early implant failure, postoperative infection, and pain/inflammation and the degree of implant stability between healthy non-penicillin-allergic individuals receiving a single prophylactic dose of 600 mg clindamycin versus 2 g amoxicillin at 1 h before implant surgery., Materials and Methods: A single-center double-blinded RCT study with parallel groups was undertaken. Eighty-two patients fulfilled study inclusion criteria and were randomly assigned to the amoxicillin (n = 41) or clindamycin (n = 41) group. The primary outcome variable was early implant failure. The presence of infection was evaluated immediately after surgery and on days 7, 14, 30, and 90, and postoperative pain/inflammation was assessed daily on days 1 to 7 post-surgery. Resonance frequency analysis was used to measure primary and secondary implant stability., Results: One early implant failure was observed (1/81), in a patient from the amoxicillin group. No statistically significant between-group differences were observed in early implant failure rate, postoperative infection rate up to 90 days, pain/inflammation scores during the first week post-surgery, or primary or secondary stability values., Conclusions: A single dose of 600 mg clindamycin before implant surgery does not increase the risk of early implant failure or infection., Clinical Relevance: These findings suggest that a single dose of 600 mg clindamycin at 1 h before implant surgery is a safe antibiotic prophylactic approach; however, when a more prolonged antibiotic therapy is required, it appears advisable to prescribe an alternative antibiotic to avoid adverse effects., Competing Interests: Declarations Ethical approval All procedures performed in this study involving human participants were in accordance with the ethical standards of the ethical committee of the University of Granada and with the 1964 Helsinki Declaration. Informed consent Informed consent was obtained from all individual participants in the study. Competing interests The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To evaluate the survival and clinical quality of individually layered indirect composite restorations (ICRs) in the mixed and permanent dentition at two study centers., Materials and Methods: A total of 155 adhesively cemented ICRs in 34 participants (aged 6 to 50 years and treated between 2008 and 2018) were evaluated for survival and clinical quality. All were individually layered restorations fabricated from laboratory sculptable composites by a specialized dental technician. Two calibrated independent investigators examined and graded each restoration as success, survival with repair, or failure based on the FDI criteria. The marginal quality and gap width of the restorations were analyzed by scanning electron microscopy. The periodontal health of treated teeth (TT) was evaluated in comparison with that of unrestored control teeth (CT) by measuring the pocket depth (PD), clinical attachment level (CAL), sulcus bleeding index (SBI), and the modified Turesky Plaque Index (TPI). A serial t-test (p 0.05) was used for statistical analysis of periodontal parameters. Success and functional survival rates were calculated using the Kaplan-Meier method., Results: Molar incisor hypomineralization (MIH) was the most common indication for treatment (41%). The median age at treatment was 14.9 years (68%-CI: 7.7-29.5). The median service time of the restorations was 5.7 ± 3.4 years. 132 restorations were classified as a success, 21 as survival with repair, and 1 as a failure. The success rates at 1, 5, and 10 years were 95.4%, 87.4%, and 78.8%, respectively, and the corresponding functional survival rates were 100.0%, 98.9%, and 98.9%. The clinical quality, encompassing esthetic, functional, and biological criteria, was rated as excellent or good in over 90%. Periodontal response, however, was the only criterion showing worse results since restored teeth (TPI = 1.9) had significantly more plaque than CT (TPI = 1.7; p = 0.0001). No significant differences were observed in PD, CAL, or SBI. The mean marginal gap width was 135.7 µm and 63.8% of the restorations had perfect margins., Conclusion: ICRs are suitable for minimally invasive restoration of large tooth structure defects in the developing dentition of children and adolescents and for long-term temporary restoration of the adult dentition.

Objective: The objective of this study is to evaluate the effectiveness of two different viscosities of short fiber-reinforced composite resin (SFRC) cores and two different viscosities of veneering composite resins on the fracture strength of direct occlusal veneers., Materials and Methods: One maxillary premolar was virtually prepared for an occlusal veneer and printed into resin dies. In total, (n = 48) resin dies were printed and assigned into three groups according to the type of core material of the occlusal veneer; mono-structured without a SFRC core, a high viscosity SFRC core, and a low viscosity SFRC core. Each group was re-divided into two subgroups (n = 8) according to the veneering composite resin; packable composite resin and injectable composite resin. Mono-structured and bi-structured direct occlusal veneers were fabricated on the resin dies using the mentioned core and veneering materials with the occlusal replica technique. Fracture strength was evaluated using a universal testing machine and the mode of failure was inspected. Statistical analysis to compare the core and veneering materials was performed using independent t test (P ≤ 0.05) and one-way ANOVA followed by tukey's post hoc test (Pa ≤ 0.0166) when appropriate. Interactions between subgroups were tested using two-way ANOVA, and one-way ANOVA was used to compare all subgroups followed by tukey's post hoc test (Pa ≤ 0.0033). Intergroup comparison between failure modes were performed using chi square test (Pa ≤ 0.0033)., Results: The presence of a SFRC core significantly improved the fracture strength of the specimens. There was no significant difference between the fracture strength of high viscosity SFRC and low viscosity SFRC cores. Specimens veneered with injectable composite resin had significantly superior fracture strength compared to packable composite resin. Additionally, there was a weak correlation between fracture strength and mode of failure., Conclusion: Short fiber reinforced composite resin significantly increases the fracture strength of direct occlusal veneers. Injectable composite resin has significantly higher fracture strength than packable composite resin as veneering materials of direct occlusal veneers., Clinical Relevance: Bi-structured direct occlusal veneers fabricated of injectable composite resin with low viscosity SFRC cores can withstand high masticatory forces in stress-bearing areas., Competing Interests: Declarations Ethics approval and consent to participate This study did not include any human participants, the human premolar tooth used in this study was extracted for orthodontic purposes and obtained with the approval of the Research ethics committee of Ain Shams University (FDASU) whom exempted this study (file number: FDASU-Rec EM012349) in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Objectives: The primary objective of this study was to compare implant survival rates (ISR) in patients undergoing maxillary sinus floor augmentation (MSFA) with lateral approach with and without membrane perforation. Secondary objectives were to establish the percentage of perforations in these procedures and to evaluate the influence of perforation size on ISR., Materials and Methods: This retrospective study included patients requiring MSFA with lateral approach. Cases were assigned to two groups according to the occurrence or not of perforation. The exact size of each perforation was registered. Descriptive statistics and associations between the groups were calculated., Results: This study analyzed data from 90 MSFA in 72 patients. Membrane perforation occurred in 24.44%. A total of 170 implants were placed; 72.35% were placed under intact membranes and 27.65% on repaired membranes. The overall ISR in MSFA procedures with intact membranes was 98.37%, and 93.62% in perforated membranes. No statistically significant relationship between groups was observed although the odds of implant failure increased by 4.125 times when perforation occurred. In turn, no statistically significant relationship was observed between perforation size and ISR., Conclusions: Implants inserted below repaired membranes had a lower ISR compared with implants inserted below intact membranes although the difference was not statistically significant. Moreover, no significant statistical correlation was observed between perforation size and ISR., Clinical Relevance: Membrane perforation does not have a significant influence on subsequent implant survival rates. Knowledge of the exact size of the membrane perforation is essential for deciding on the right treatment plan., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aim: to compare two-year clinical success rates of caries management in children (Hall Technique HT, Nonrestorative caries treatment NRCT, Conventional restorations CR), and to evaluate pain perception, behaviour, technique acceptability by patients, parents and dentists., Methods: 122, 3-8-year-olds were enrolled in 2-year parallel group randomised controlled trial (CR, n = 52, HT, n = 35, NRCT, n = 35). Caries was recorded using Nyvad criteria to measure clinical success/ failure rates. Child's pain perception (Visual Analogue Scale of Faces), child behaviour (Frankl scale), parents' and dentists' treatment opinions (5-point Likert scale) were assessed. Statistical analysis included Chi-square, non-parametric Kruskal-Wallis, Bonferroni-corrected Mann-Whitney U tests (p < 0.05), absolute risk reduction (ARR) and number needed to treat (NNT)., Results: After two years, with 116 participants, clinical success rates were: CR=60.8 % (n = 31), HT=93.8 % (n = 30), NRCT=42.5 % (n = 14) (p < 0.001). Major/minor failure rates differed: CR=17.6 % (n = 9) / 21.6 % (n = 11); HT=6.2 % (n = 2)/ 0 %, NRCT=33.3 % (n = 11)/ 24.2 % (n = 8), (p < 0.05). When comparing HT to CR, ARR = 0.33; NNT= 3 (95 % CI 0.02 -0.58); NRCT to CR, - no observed benefit from NRCT. More than 70 % of children demonstrated "positive/definitely positive" behaviour during treatment. Pain intensity was "very low/low" in 92.3 % of cases for CR, 88.6 % for HT, and 77.1 % for NRCT . NRCT was "very easy" to perform for 82.9 % of participants, compared to 42.3 % for CR and 17.1 % for HT (p < 0.05). CR were reported to take longer than NRCT and HT (p < 0.05)., Conclusion: Clinical success rates of HT were superior to CR and NRCT. All treatment techniques were well tolerated by children, CR was more time-consuming and HT - technically more difficult to perform., Clinical Significance: caries management in primary molars can be successfully performed using minimal intervention, particularly, sealing in caries lesions with Hall technique. NRCT can prevent caries progression when adequate access to mechanical plaque disruption and fluoride is provided. However, occasional fluoride application, and uncontrolled toothbrushing with fluoride toothpaste cannot replace restorative procedures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: There is a paucity of data on the outcome of fixed tooth- and implant-supported porcelain-fused-to-metal (PFM) and ceramic-based (CB) restorations fabricated during undergraduate dental education. Therefore, this retrospective study examined the outcome of fixed restorations placed in patients participating in an undergraduate program., Methods: Patient records were searched for data on fixed PFM and CB restorations. For these restorations, the functional period in situ and technical and biological complications, namely restoration fracture, decementation, screw loosening, secondary caries, and loss of vitality, were recorded. Periodontal parameters were also documented. Kaplan-Meier survival and complication estimates after 1 and 5 years were calculated for restoration types, materials, designs (veneered/non-veneered), cementation/retention modes and localizations with group sizes ≥ 15. Regression models were used to analyze the influence of demographic data and abovementioned restoration characteristics on restoration survival, technical and biological outcome., Results: 1196 restorations with a mean observation time of 5 years were included in the analysis. The different restoration types exhibited survival rates of > 90.8% after 5 years, accompanied by a favorable biological outcome. However, monolithic resin-matrix or feldspathic ceramic restorations were found to have a higher fracture rate than lithium disilicate or zirconium dioxide ceramic restorations resulting in lower survival rates for these restorations. Additionally, resin-matrix ceramic restorations showed a higher decementation rate than lithium disilicate restorations., Conclusions: Fixed tooth- and implant-supported CB restorations fabricated from lithium disilicate and zirconium dioxide ceramics demonstrated better survival and lower complication rates than restorations fabricated from resin-matrix or feldspathic ceramics in an undergraduate dental education program., Clinical Significance: Due to the more favorable outcome of CB restorations fabricated from lithium disilicate or zirconium dioxide ceramics, undergraduate dental education should focus on the application of these ceramics to increase restoration survival by reducing technical complications., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Abutment screw fracture is a mechanical complication associated with the failure of dental implant-supported restorations. Retrieval of fractured abutment screws without damaging the internal surface of implants is challenging and can be time-consuming. Microtube extraction devices are used to remove separated endodontic instruments. This article presents a conservative method of retrieving a fractured implant abutment screw using a microtube device., (Copyright © 2022 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: This study assessed the fatigue lifetime of reduced-diameter implants placed in either bovine rib or polymer-based bone model., Methods: Bovine ribs were classified according to the criteria proposed by Lekholm and Zarb and were analyzed for bone fraction. Fourteen dental implants (3.25 mm in diameter × 15 mm in length) were placed in bovine ribs used as a bone model. They were subjected to resonance frequency analysis. Stainless steel loading hemisphere caps were bonded on the abutments position at 30-degree angle and with a moment arm of 11 mm. Accelerated life testing using the step-stress method was conducted at 2 Hz with a stress ratio of 0.1 until fracture on a servo-hydraulic load frames machine (MTS). Results were compared with those of a previous study wherein implants were placed in a polymer-based bone model. Fatigue lifetime statistics (characteristic lifetime and Weibull modulus) of physical specimens were estimated in a reliability analysis software (ALTA PRO). Fractured specimens were examined under an electron scanning microscope to determine the failure mode., Result: The implants exhibited high stability quotient values (75.07 ± 3.81). Implants placed in bovine ribs showed better data dispersion and longer fatigue lifetime than those placed in polymer-based bone models, with no significant difference between groups. All fractures occurred in the implant body near the bone level and were indicative of fatigue fractures., Significance: Bovine ribs appear to be a more suitable material for accelerated life testing than the polymer-based material because of better data dispersion., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: To evaluate the clinical performance of two flowable composites based on methacrylate and one based on ormocer in treating non-carious cervical lesions (NCCLs) after 48-month evaluation in a split-mouth double-blind clinical study design., Methods: A total of 183 restorations were performed on NCCLs using a universal adhesive system (Futurabond U, Voco GmbH) with selective enamel etching on 27 participants: two participants received twelve restorations each, three received nine restorations each, and 22 participants received six restorations each. Three different flowable composites were employed (n = 61): a low-viscosity methacrylate-based composite (GrandioSO Flow, LVM), a high-viscosity methacrylate-based composite (GrandioSO Heavy Flow, HVM), and an ormocer-based flowable composite (Admira Fusion Flow, ORM). All restorations were evaluated using FDI and USPHS criteria after 48 months. Statistical analysis was conducted using Kaplan-Meier Survival analysis and Kruskal-Wallis analysis of variance rank (α = 0.05)., Results: After 48 months, 17 restorations were lost: LVM 6, HVM 9, ORM 2. The retention rates (95 % confidence interval) were 89.4 % for LVM, 80.4 % for HVM, and 95.6 % for ORM, with a significant difference between HVM vs. LVM and HVM vs. ORM (p < 0.05). Minor defects were observed in 30 restorations for marginal staining criteria (LVM 12, HVM 10, ORM 8) and in 71 restorations for marginal adaptation criteria (LVM 24, HVM 20, ORM 27) without significant difference between groups (p > 0.05). No restorations showed postoperative sensitivity or recurrence of caries., Significance: The increased viscosity of flowable composites could reduce the clinical longevity in NCCLs after 48 months. Ormocer-based and low-viscosity methacrylate-based flowable composites showed a successful clinical performance in NCCLs after 48 months., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Paediatric-preformed zirconia crowns have been associated with several issues, primarily their inability to be crimped and the need for extensive tooth preparation. Additionally, the capacity to adjust the size, shape, and fit of these crowns is very limited., Aim: To evaluate and compare the fracture strength of four different types of dental crowns intended for paediatric patients., Design: The fracture resistance of four types of paediatric crowns was evaluated using the universal testing machine; freshly extracted primary molars received one of the following: preformed zirconia crowns, custom-made computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia crowns, custom-made CAD-CAM ceramic crowns, and custom-made CAD-CAM hybrid composite crowns. Data were statistically compared using the Kruskal-Wallis test followed by the Bonferroni test, and the level of significance was set at 5%., Results: Results showed that there was a statistically significant difference among the four groups (p < .001). The highest value of fracture force was observed for the milled zirconia crown and the lowest for the prefabricated zirconia., Conclusion: The implementation of the CAD-CAM digital crown fabrication technique has the potential to address issues associated with preformed crowns in paediatric patients, particularly in terms of fracture resistance., (© 2024 BSPD, IAPD and John Wiley & Sons Ltd.)

Objective: To assess the clinical performance of monolithic screw-retained implant-supported zirconia crowns (MSI) bonded or mechanically retained on prefabricated Ti-bases using a complete digital workflow., Methods: A retrospective analysis was conducted on patients who underwent single dental implant procedures between January 2017 and May 2018. Inclusion criteria were: patients over 18 years of age; implants placed in posterior sites; MSI on prefabricated Ti-base realized by using a complete digital workflow; a minimum follow-up period of 2 years. Cemented crowns and fixed dental prosthesis were excluded. Mechanical complications included: fracture of Ti-base; loss of retention; loosening of Ti-base screws. Technical complications included: fracture and debonding of monolithic zirconia. Biological complication was set strictly at a probing pocket depth of 5 mm and bleeding on probing or pus secretion., Results: A total of 144 dental implants placed in 127 patients were included, 73 with a fully tapered implant system (BLX) and 71 with a conical connection system (Nobel Parallel CC). Of the 73 BLX implants, 4 experienced loosening of the Ti-base screw, while 3 Nobel Parallel CC implants experienced the same problem. In addition, 4 fractures of the Ti-base and 6 fractures of the inner surface of the monolithic zirconia were observed in the Nobel Parallel CC implants. Cumulative survival was 100 % for bonded crowns and 85 % for mechanically retained crowns. Radiographic evaluation revealed a mean CBL of 0.12 mm for the BLX and 0.13 mm for the Nobel Parallel CC implants with no statistically significant differences between the Ti-base types. There was no evidence of bleeding on probing or pus secretion. All probing pocket depths were <3 mm., Conclusion: The use of a prefabricated Ti-base remains a clinically acceptable choice, however, MSIs bonded to prefabricated Ti-bases had fewer mechanical and technical complications than the MSI mechanically retained to a prefabricated Ti-base., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Various types of crowns are used for full-coverage restoration of primary teeth affected by caries, developmental defects, or after pulp therapy. Prefabricated Stainless Steel and Zirconia crowns are commonly utilized. Bioflx crowns, which blend the properties of Stainless Steel and Zirconia, provide a flexible and aesthetically pleasing alternative., Aim: This study aimed to evaluate the vertical marginal gap and fracture resistance of Bioflx pediatric crowns compared to Zirconia and Stainless Steel crowns following thermomechanical aging., Methods: This in-vitro study was conducted using mandibular second primary crowns of three different materials (n = 30). Crowns were divided into three groups; Zirconia crowns group (n = 10, Nu Smile, USA), Bioflx crowns group (n = 10, Nu Smile, USA) and Stainless Steel crowns group (n = 10, Nu Smile, USA). The crowns were cemented onto standardized acrylic resin dies and subjected to thermomechanical aging. Vertical marginal gap measurements were obtained using a USB digital microscope with an integrated camera, while fracture resistance was assessed with a universal testing machine. Data were analyzed for outliers and tested for normality using the Shapiro-Wilk or Kolmogorov-Smirnov tests, with statistical significance set at 0.05., Results: Significant differences were observed in the vertical marginal gaps among the groups after cementation and thermomechanical aging (P = 0.013 and P = 0.001, respectively). Zirconia crowns exhibited the largest average marginal gap, followed by Bioflx and Stainless Steel crowns. Stainless steel crowns demonstrated the highest fracture resistance, followed by Bioflx crowns, while Zirconia crowns showed the lowest., Conclusions: Bioflx crowns exhibit the largest vertical marginal gap but show greater fracture resistance compared to Zirconia crowns, although they are still less resistant than Stainless Steel crowns after undergoing thermomechanical aging., (© 2024. The Author(s).)

Objectives: This systematic review attempted to assess patient acceptance of repairs instead of complete replacement for partially defective restorations and to identify factors affecting patients' decision-making for or against repairs., Study Selection: Observational and qualitative studies reporting on (1) the proportion of patients accepting or preferring repairs, (2) the proportion of dentists / dental students / dental schools stating that their patients accept or prefer repairs, (3) factors affecting patients' decision-making for or against repairs., Sources: Electronic databases (MEDLINE via PubMed, Scopus, EMBASE via Ovid, and Web of Science) were last searched in August 2024 (PROSPERO database: CRD42023449437)., Data: Twenty-one sources reporting on 20 survey studies addressing individual dentists / dental students and dental schools were included. None of the included studies directly addressed patients (e.g., by interviewing patients). Of the surveyed dentists and dental students, 86.3 % (95 %-CI: 77.8-91.8 %) reported that their patients accept or prefer repairs. Dental schools rated patient acceptance as high as 93.0 % (95 %-CI: 82.3-97.4 %). None of the included studies reported factors affecting patients' decision-making for or against repairs., Conclusions: Repairs of partially defective restorations instead of complete replacement seem to be associated with a high level of patient acceptance as most dentists, dental students, and dental schools stated that their patients accept or even prefer repairs instead of complete replacement., Clinical Significance: Within the shared decision-making process, dentists can expect their patients to accept or even prefer repairs instead of complete replacement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: The goal of this systemic review and meta-analysis was to compare the longevity of direct and indirect composite restorations in posterior teeth., Data: Randomized controlled trials (RCT) investigating direct and indirect composite restorations in permanent posterior teeth., Sources: Three electronic databases (PubMed, CENTRAL (Cochrane) and Embase) were screened. No language or time restrictions were applied. Study selection, data extraction and quality assessment were done in duplicate. Risk of bias and level of evidence was graded using Risk of Bias 2.0 tool and Grade Profiler 3.6., Results: A total of 3056 articles were found by electronic databases. Finally, five RCTs were selected. Overall, 627 restorations of which 323 were direct and 304 indirect composite restorations have been placed in 279 patients (age: 28-81 years). The highest annual failure rates (AFR) were found for indirect restorations ranging from 0 % to 15.5 %. Lower AFR were found for direct restorations ranging from 0 % to 5.4 %. The most frequent failures were found to be chipping and fracture of the restoration followed by caries. Meta-analysis revealed that the failure rate for direct restorations was significantly lower than for indirect restorations (Risk Ratio (RR) [95 %CI] = 0.61 [0.47; 0.79]; very low level of evidence). Furthermore, all studies showed a high risk of bias., Conclusion: Direct and indirect composite restorations can be recommended for large class II cavities including cusp coverage in posterior teeth for single tooth restoration. Meta-analysis revealed significantly lower relative risk to fail for direct composite restorations than for indirect restorations but results are with high risk of basis., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: To assess the impact of elastic gradients formed among restorative material, cement, and substrate on the fracture resistance of tri-layer restorative systems., Methods: Four CAD/CAM materials were utilized, two glass-ceramics (IPS e.max CAD, Vita Suprinity) and two resin-ceramic hybrids (Vita Enamic, Lava Ultimate). Their fracture resistance was examined by biaxial flexure (n = 8) and Hertzian indentation (n = 10) tests. Statistical analysis was conducted using ANOVA and Tukey tests (p = 5 %). Finite element analysis (FEA) was employed to simulate the Hertzian indentation test and elucidate the stress-fields formed on the intaglio surface below the loading area., Results: The biaxial flexural strength (MPa) of glass-ceramics exceeded the hybrid materials (e.max 417 a , Suprinity 230 b , Enamic 138 c , and Lava Ultimate 183 bc ). Conversely, the load-bearing capacity (N) of the materials bonded to dentin analog demonstrated the opposite trend, with the hybrid materials achieving superior results (e.max 830  C , Suprinity 660 D , Enamic 1822 B , and Lava Ultimate 2593  A ). The stress-fields observed by FEA were coherent with the experimental results for Hertzian flexural stresses (MPa): e.max 501  A , Suprinity 342  C , Enamic 406 B , whereas no tensile stress was observed at the intaglio surface of Lava Ultimate., Significance: Detailed analysis of the fracture resistance of the tri-layer restorative systems showed that the elastic gradients play a more significant role than the flexural strength of the restorative materials. The coherence of the elastic moduli between the restorative material and supporting structures results in reduced tensile stress concentration at the intaglio surface beneath the loading area and enhances the ability to withstand load., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The present in vitro study aimed to evaluate the fatigue behavior of teeth filled with a calcium silicate-based sealer (Bio-C Sealer, BC) or an epoxy resin-based sealer (AH Plus, AH), in bulk or associated with gutta-percha as main core material., Methods: Seventy-two sound human maxillary anterior teeth were initially selected. Sixty of them, were randomly chosen, and had their root canals prepared using nickel-titanium reciprocating instruments, being again randomly assigned to five experimental groups ( n = 12): C+ (control + prepared but not filled); BC-B (BC in bulk); BC-GP (BC+ gutta-percha); AP-B (AH in bulk); AP-GP (AH+ gutta-percha). An additional negative control group (C-) was considered ( n = 12), consisting only on sound teeth, without preparation and filling. The specimens were submitted to a survival analysis after the cyclic fatigue test., Results: Sound teeth (C-) presented the best fatigue performance ( P < 0.05), being similar only to the AP-GP group ( P > 0.05). Despite that, all experimental groups showed similar fatigue behavior ( P > 0.05) to C+ (BC-B = BC-GP = AP-B = AP-GP = C+). Based on that, it can be seen that the use of gutta-percha, as a main core material, associated with the AH Plus sealer, reestablished the mechanical fatigue performance of endodontically treated teeth comparable to sound teeth, still consisting on the most promising approach to rehabilitate such scenario. Teeth filled in bulk, had discreetly higher risk of premature failures and inferior fatigue performance., Competing Interests: João Tribst is an Academic Editor for PeerJ., (© 2024 Lena et al.)

Objectives: To evaluate clasp-retained removable partial dentures (C-RPDs) with a metal framework for survival, maintenance requirements, and biologic implications., Method and Materials: C-RPDs were retrospectively analyzed based on patient records. Treatment failure was defined as fracture of a framework component (metal base or connector) or loss of an abutment tooth. Other outcome variables included factors that might conceivably impact C-RPD survival (maxilla vs mandible, Kennedy classes, opposing dentitions, treatment by students vs certified dental practitioners), mobility and caries of abutment teeth (in relation to clasp designs), and maintenance requirements (relining, clasp or resin fractures). Differences were evaluated by appropriate statistical tests at the P ≤ .05 level., Results: A total of 612 patients (339 men, 273 women) 60.0 ± 11.5 years old at delivery were included, covering 842 C-RPDs and a mean observation period of 42.1 ± 33.2 months. Kaplan-Meier C-RPD survival was 76.2% after 5 years and 49.5% after 10 years. Biologic complications (ie, loss of abutment teeth) accounted for the vast majority (95.6%) of C-RPD failures, and Kaplan-Meier C-RPD survival was significantly better in the mandible (P = .015). Some clasp designs contributed significantly to caries and removal of abutment teeth (both P .05). No other significant differences were noted., Conclusion: Tooth loss both emerges as the main cause of C-RPD failure and might be amenable to careful selection of clasp designs. Overall, better C-RPD survival should be expected in the mandible. A noncontributory role of Kennedy classes and opposing dentitions is tentatively suggested based on numerically heterogenous subgroups.

Background: The materials used in root canal filling and radiotherapy (RT) application can affect the load-to-failure of the teeth. This study aimed to compare the load-to-failure of the teeth filled with AH Plus (AHP) or AH Plus bioceramic (AHPB) before or after 60 Gy- and 70 Gy-dose radiotherapy., Materials and Methods: One hundred and ten maxillary incisors were endodontically prepared up to ProTaper Next X4 instruments. The teeth were randomly divided into 5 main groups as: non-irradiated, root canal treatment (RCT) before 60 Gy radiotherapy, RCT before 70 Gy radiotherapy, RCT after 60 Gy radiotherapy, RCT after 70 Gy radiotherapy. These groups were divided into 2 subgroups for filling material: AHP ve AHPB. After filling and radiotherapy procedures, the teeth were fixed on the thermoplastic mask plane. The plane were placed in the middle of a rectangular prism shaped glass phantom, and irradiated via a linear accelerator device. The teeth were then embedded in cylindrical acrylic blocks and the force (N) that caused the fracture was recorded under the Universal testing device. Student t-test was used for statistical comparisons. Statistical significance level was determined as p < 0.05., Results: After 70 Gy dose radiotherapy, the group filled with AHPB showed statistically significantly lower fracture strength than the group filled with AHP (p < 0.05). In the control group, before 60 Gy RT group, after 60 Gy RT group, and before 70 Gy RT group, the sealers had statistically significantly similar load-to-failure. (p > 0.05)., Conclusion: The group filled with AHPB caused a lower fracture strength than the group filled with AHP following a 70 Gy dose of RT. The sealers in the control group, before 60 Gy RT group, after 60 Gy RT group, and before 70 Gy RT group exhibited comparable load-to-failure values., (© 2024. The Author(s).)

Purpose: This study investigated the fracture resistance of 0.5-mm-thick restorations for minimally invasive therapy. Anterior partial-coverage crowns composed of three-dimensional (3D)-printed 3-mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP; Lithacon 3Y210, Lithoz) and 3D-printed composite (Varseo Smile Crown plus, Bego) were compared with a control group made from milled 3Y-TZP (Cercon ht, DentsplySirona)., Methods: Three groups each with 27 restorations were produced. For milled 3Y-TZP partial-coverage crowns, drill compensation was needed so the milling bur could access the inner surface at the incisal edge. Restoration fit was verified by cross-sectioning 12 specimens in each group. The remaining 15 restorations were sandblasted (Al2O3, 0.1 MPa) and adhesively cemented (Panavia SA, Kuraray) onto CoCr teeth. Static load-to-failure tests were performed. The load was induced on the incisal edge. The forces needed to fracture the specimens were analyzed using the Welch analysis of variance and post hoc Dunnet-T3 tests. The Weibull parameters were also calculated., Results: Drill compensation increased cement thickness at the loading area by 200 µm in milled 3Y-TZP restorations compared with the 3D-printed partial-coverage crowns. Fracture resistance was the highest in 3D-printed 3Y-TZP restorations (1570±661N) followed by milled 3Y-TZP (886±164N) and 3D-printed composite partial-coverage crowns (570±233 N). Milled 3Y-TZP was associated with a substantially higher Weibull modulus (m=6) than the 3D-printed materials (m=2), suggesting greater reliability., Conclusions: Fracture resistance increased with tighter fit, demonstrating the benefit of the geometric freedom associated with 3D-printing. Future research should focus on making 3D-printed 3Y-TZP more reliable to increase its safety in clinical use.

Purpose: This in vitro study investigated the influence of material selection, crown morphology, and vertical crown height on the biomechanical behavior of screw-retained monolithic hybrid abutment crowns (HACs)., Methods: Ninety implants were embedded in accordance with ISO standard 14801; ninety HACs were mounted (N=90). Monolithic crowns with varying group-specific designs were luted using titanium bases. HACs were fabricated from monolithic lithium disilicate ceramic (LD) or zirconia-reinforced lithium silicate ceramic (ZLS). The crown morphology was either maxillary premolar (LD&#95;PM, ZLS&#95;PM) or molar (LD&#95;MO). The three groups were further divided into three subgroups of ten specimens, each designed with a small (7.5 mm), middle (10.5 mm), and high (13.5 mm) configuration of crown heights (N=10). A load-to-failure test at 30° off-axis was conducted using a universal testing machine until failure. For statistical analysis, Kolmogorov-Smirnov and Mann-Whitney U tests were conducted (P < 0.05)., Results: All LD&#95;MO groups presented the highest failure values (808.7 to 947.9 N), followed by the LD&#95;PM (525.8 to 722.8 N) and ZLS&#95;PM groups (312.6 to 478.8N). A comparison between LD and ZLS materials (P < 0.001) as well as the crown morphology (P < 0.001) showed significant differences in failure values. The values in the subgroups of ZLS&#95;PM (low, middle, high) decreased as the crown height increased. The fracture modes showed no consistent patterns across the test groups., Conclusions: Material selection, crown morphology, and vertical crown height appear to be important factors that may influence the clinical failure values and patterns of screw-retained single implant crowns.

Purpose: To compare the influence of immediate loading (IL) and non-immediate loading (NIL) protocols on overdentures retained by reduced-diameter implants (≤ 3.5 mm)., Materials and Methods: Electronic databases including MEDLINE (via PubMed), Embase, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) comparing clinical outcomes of immediately loaded and non-immediately loaded reduced-diameter implants supporting overdentures. The risk of bias within and across the studies and the certainty of evidence were assessed by RoB 2.0 and GRADE, respectively. A sensitivity analysis was performed by eliminating studies at high risk of bias and repeating the data synthesis employing the random effects model. Subgroup analyses were conducted based on the implant diameter and the length of follow-up., Results: Overall, six RCTs with 255 patients were included in this systematic review. The meta-analyses found similar implant survival rates between immediately loaded and non-immediately loaded implants in the mini-implant (RR &#61; 0.98; 95% CI &#61; 0.95, 1.01; P &#61; .12) and narrow-diameter implant subgroups (RR &#61; 0.99; 95% CI &#61; 0.94, 1.03; P &#61; .56) as well as in short-term (RR &#61; 0.98; 95% CI &#61; 0.97, 1.00; P &#61; .11) and long-term (RR &#61; 0.97; 95% CI &#61; 0.93, 1.01; P &#61; .09) follow-up subgroups. Additionally, marginal bone loss (MBL) showed no statistically significant difference between the loading protocols in the subgroup of long-term follow-up (MD &#61; 0.03; 95% CI &#61; -0.16, 0.23; P &#61; .74). Three RCTs investigating peri-implant parameters found relatively higher modified plaque index (PI) and probing depth (PD) in reduced-diameter implants under IL., Conclusions: Compared with NIL, the IL protocol can achieve comparable survival rates and MBL in reduced-diameter implants supporting overdentures.

Purpose: This study aimed to evaluate the 10-year outcomes of partial fixed dental prostheses (P-FDPs) fabricated using metal-free fiber-reinforced composite (FRC) resin frameworks veneered with composite resin and supported by short and extra-short implants., Methods: This study included 28 patients with 38 FRC prostheses supported by 96 implants. Implant and prosthesis survival and success rates were evaluated using Kaplan-Meier analysis., Results: The 10-year implant survival and success rate, as determined by Kaplan-Meier analysis, was 96.9%, and the prosthesis survival and success rates were 94.7% and 92.0%, respectively. None of the parameters under investigation were significantly correlated with prosthetic survival or successful outcomes, but three parameters were correlated with higher peri-implant bone levels: implant placement in the mandible as opposed to the maxilla, shorter P-FDP spans, and natural teeth on the opposing arch., Conclusions: FRC P-FDPs supported by short and extra-short implants presented high, up to 10-year, survival and success rates, when used to restore partially edentulous arches.

Aim: The objective of the present study was to investigate the effect of using different materials for the fabrication of implant abutments and crowns on the mechanical behavior of implant-supported single crowns after artificial aging. The materials were tested in different combinations to reveal whether using stiff or resilient materials as an abutment or a crown material might influence the fracture strength of the whole structure., Materials and Methods: A total of 40 implants (blueSKY) were restored with identical custom-made CAD/CAM abutments milled out of lithium disilicate or ceramic-reinforced polyetheretherketone (PEEK) and divided into five test groups (n &#61; 8). Forty crowns made of three different materials (zirconia, lithium disilicate, and ceramic-reinforced PEEK) were used to restore the abutments. Specimens were subjected to mechanical loading up to 1,200,000 cycles in a chewing simulator (Kausimulator) with additional thermal cycling. The surviving specimens were subjected to quasi-static loading using a universal testing machine (Z010)., Results: The PEEK abutments with zirconia crowns showed the highest median failure load (3890.5 N) while the PEEK abutments with lithium disilicate crowns exhibited the lowest (1920 N). Fracture and deformation occurred in both the crowns and abutments., Conclusion: The failure load of the restorations was influenced by the material of the abutment and crown. Restoring PEEK abutments with zirconia crowns showed a high failure load and no screw loosening.

Aim: The aim of the present in vitro study was to investigate the effects of different sintering procedures on the fit, color parameters, and fracture load of monolithic fixed partial prostheses (FPPs)., Materials and Methods: A metal master model was scanned and FPPs were designed. Groups were created by fabricating FPPs using four different sintering procedures (n &#61; 10): Prettau-Standard (PST); Prettau-Slow (PSL); Ice-Speed (ISP); Ice-Standard (IST). PST-PSL (Group P; N &#61; 20) and ISP-IST (Group I; N &#61; 20) were colored with different coloring liquids. The marginal and internal fit were measured using the silicone replica method. CIELAB values of the samples were measured using a spectrophotometer. Then, for each sample, the die was obtained from polymethyl methacrylate. The specimens were cemented into dies and tested in a universal testing machine for fracture load. One-way ANOVA was performed to assess the effect of the sintering procedure on the marginal and internal fit; fracture load; and ∆E00, ∆L', ∆C', and ∆H' values of the FPPs., Results: The PSL and PST groups showed significantly smaller internal and marginal fit values compared with the ISP group. Additionally, the internal fit values of the IST group were significantly higher than those of Group P. Sintering time reduction led to a decrease in ∆E00 values. Fracture load values were not statistically significantly affected by the different sintering procedures for both brands., Conclusion: Different sintering procedures did not have a clinically significant effect on fit and fracture load. Different sintering procedures were found to have an impact on the color change of monolithic zirconia restorations.

Background: Bioactive surface modifications have been proposed to enhance osseointegration and longevity of dental implants. This study aimed to systematically review and perform a meta-analysis on the effectiveness of various bioactive coatings in promoting bone integration and improving implant longevity., Methods: A systematic review was conducted, including studies that investigated bioactive surface modifications on titanium dental implants. Outcomes of interest were bone-to-implant contact (BIC) and implant longevity over a 30-day period. Data were extracted and analyzed using RevMan 5 (version 5.4.1), with forest plots generated to represent the mean difference (MD) and 95% confidence intervals (CI) under a random effects model., Results: The meta-analysis showed a significant improvement in BIC for surface-modified implants, with an overall MD of 7.29 (95% CI [2.94, 11.65]). Heterogeneity analysis indicated moderate heterogeneity (Tau² = 18.57, Chi² = 16.08, df = 8, P = 0.04, I² = 50%). The test for overall effect yielded Z = 3.28 (P = 0.001). For implant longevity, the overall MD was 7.52 (95% CI [3.18, 11.85]), with moderate heterogeneity (Tau² = 17.28, Chi² = 14.95, df = 8, P = 0.06, I² = 47%). The test for overall effect yielded Z = 3.40 (P = 0.0007)., Conclusion: Bioactive surface changes significantly improved osseointegration and lifespan of dental implants. Collagen-based coatings consistently encouraged early bone integration, while BMP-2 combinations were effective for osseointegration. Optimizing bioactive agent doses and combinations was critical for achieving desired outcomes., (© 2024. The Author(s).)

Background: This study evaluates the fracture strength and patterns of feldspathic porcelain restorations made using CAD/CAM technology for lower first molars with extensive crown destruction. The restorations include post-core and full-contour crown, composite resin core and full-contour crown, and endocrown. This research provides insights into effective restorative options to address tooth fracture risk, supporting minimally invasive procedures and CAD/CAM integration in dental practices., Methods: This study utilized 80 permanent mandibular first molars, which were divided into four groups: Group I (Post-Core-Full-contour crown), Group II (Core- Full-contour crown), Group III (Endocrown), and Group IV (Control). Root canal treatment was performed on all samples except for the control group. Following access cavity preparation, restorations for each tooth were fabricated using the CAD/CAM system and cemented with resin cement. The specimens were embedded in acrylic blocks. After undergoing thermomechanical aging, the samples were subjected to fracture resistance testing using a universal testing machine, which applied force until fracture occurred. The fracture patterns were subsequently analyzed, and the data were statistically evaluated using the Kruskal-Wallis and Chi-Square tests (p < 0.05)., Results: A significant difference in fracture values under axial forces was observed (p < 0.05). The control group had the highest fracture strength (1830 ± 277 N), while the Core- full-contour crown group showed the lowest (1532 ± 371 N). Failure types varied significantly among the groups (χ2 = 26.886, df = 9, p = 0.001). The most common failure type was Type-2 (33.75%), characterized by restorable fractures, while Type-3 fractures, unrestorable, were the least common (12.5%)., Conclusions: The findings underscore the significance of technological advancements in CAD/CAM for effectively restoring endodontically treated teeth with extensive crown damage. This study contributes valuable insights, emphasizing the clinical relevance of selecting appropriate restorative options to mitigate the risk of tooth fracture associated with coronal restoration failures., (© 2024. The Author(s).)

Although transcrestal sinus floor elevation (TSFE) is widely used for cases of insufficient residual bone height in the posterior maxilla, few studies focus on the risk factors of early implant failure associated with TSFE procedures. This study aimed to identify and summarize the possible risk factors of implant failure associated with TSFE to ensure a more predictable implant survival rate using TSFE. We report the treatment of a patient with implant failure following TSFE and discuss this case's possible associated risk factors. A standard implant with a diameter of 4.8 mm and length of 10 mm was used after the TSFE procedure. Implant loosening was suddenly observed 6 weeks after the initial surgery. Factors that could result in early implant failure included patient-related risk factors, anatomical factors of the operational area, and operation- and implant-related factors. Within the current study's limitations, the graft material particles between the implant surface and socket could be considered a direct risk factor resulting in implant failure. Therefore, more attention should be paid to socket cleaning during the TSFE procedure, and loose particulate grafting materials should be discouraged. Another significant consideration for implant loss is the possibility of fractures in the buccal or palatal cortical plates during the site preparation and implant insertion. Thus, these factors should be studied further and receive more clinical attention.

Purpose: To assess the fracture resistance and failure mode of endodontically treated premolars reconstructed by different preparation approaches: cervical margin relocation (CMR) and crown lengthening (CL) with complete ferrule (CLF) and partial ferrule (CLPF) with three different post and core systems., Materials and Methods: In this in vitro study, 100 maxillary premolars were assigned to the following 10 groups according to their preparation approach and type of post and core system (n = 10): (I) control (intact teeth), (II) prefabricated fiber post (PFP) and composite core with CMR (PFP-CMR), (III) polyethylene fiber-reinforced composite (PEFRC) with CMR (PEFRC-CMR), (IV) casting post (CP) and core with CMR (CP-CMR), (V) PFP-CLPF, (VI) PEFRC-CLPF, (VII) CP-CLPF, (VIII) PFP-CLF, (IX) PEFRC-CLF, and (X) CP-CLF. After thermomechanical loading, the fracture resistance and failure mode were assessed. Data were analyzed statistically (α = 0.05)., Results: In all post and core systems, the CLPF approach had lower fracture resistance than CMR (p < 0.05); CLF showed higher fracture resistance than CLPF only in the PFP system (p = 0.038). In PEFRC and CP systems, the difference between CLF and CLPF was not significant (p > 0.05). No significant difference was found in fracture resistance of different post and core systems with the same preparation approach (p > 0.05). CLPF showed the highest frequency of favorable, and CLF showed the highest frequency of unfavorable fractures., Conclusion: CLPF yielded lower fracture resistance than CMR. The difference in fracture resistance was not significant between CLF and CMR but the frequency of unfavorable fractures was higher in CLF than in other groups., (© 2023 by the American College of Prosthodontists.)

Purpose: To investigate the long-term implant survival rate and marginal bone loss (MBL) of implants with different variables associated over an observational period of at least 20 years., Materials and Methods: Patients with at least one implant placed prior to 2001 were recalled and visited. Data on implant macro-design, prosthetic aspects, site distribution, and patient-related factors were collected. MBL was evaluated on intraoral X-rays and peri-implant soft tissue parameters were recorded. The patients were asked to fill out a questionnaire to evaluate their satisfaction with the treatment received. Descriptive statistics indicators were estimated. Analysis of variance and analysis of covariance models were used to investigate any differences in the MBL and peri-implant probing depth (PPD) among the variables. A chi-square analysis was performed to investigate any association between different types of prosthetic implant-supported rehabilitations and survival/success outcomes., Results: Forty-one (41) patients and 174 implants were included with a mean observational period of 23.3 ± 2.8 years. The implant survival and success rates were 96.5% and 83.3% respectively, while 3.5% of early failures were detected. The lowest success rates were observed for implants supporting fixed full-arch rehabilitations (71.05%) and overdenture rehabilitations (86.11%). A mean MBL of 1.81 ± 0.71 mm and a mean PPD of 3.38 ± 1.62 mm were recorded. The interaction between the collected data with MBL and PPD did not reveal any statistically significant differences between the variables (p > 0.05). A statistically significant difference was recorded when analyzing the association between the different types of prosthetic implant-supported rehabilitations and success rates (p = 0.014), with fixed and removable full-arch rehabilitations presenting with lower success rates. Answers to the questionnaire showed a generally high level of satisfaction., Conclusions: Within the limits of this retrospective study and based on the results, an implant survival rate higher than 96% was observed after a mean observational period of 23.3 ± 2.8 years. Both the implant survival rate and MBL seemed stable after a mean observational period of 23.3 ± 2.8 years. Implants supporting fixed and removable full-arch rehabilitations seemed to present lower success rates over time. Implant rehabilitation seemed to provide patients with optimal long-term outcomes in terms of functional and psychological aspects., (© 2024 by the American College of Prosthodontists.)

Statement of Problem: Completely veneered zirconia ceramic (ZC) fixed partial dentures (FPDs) have been reported to have a higher incidence of ceramic chipping than the standard metal-ceramic FPDs. However, data from comparative long-term studies are sparse., Purpose: The purpose of this retrospective study was to compare the long-term survival, chipping-free survival, and success of ceramic-veneered high noble metal alloy (HN), base metal alloy (cobalt-chromium alloy) (CC), and ZC FPDs and to isolate risk factors for the incidence of failure, veneer chipping, and overall complications., Material and Methods: Data from 289 study participants (58.7% women; mean age, 57.97 ±11.51 years) provided with a total of 400 FPDs comprising 197 (49.3%) HN FPDs, 121 (30.3%) CC FPDs, and 82 (20.5%) ZC FPDs fabricated from presintered 3 mol% yttria-stabilized zirconia (mean time of service, 6.85 ±3.25 years) were evaluated. Of these, 278 (69.5%) FPDs were provided by dentists and 122 (30.5%) by dental students. Five- and 10-year survival, chipping-free survival, and success rates were calculated using the Kaplan-Meier method and compared with the log-rank test. Risk factors were assessed using Cox regression analysis. The study was exploratory, so all P values were considered exploratory and descriptive., Results: The 5- and 10-year survival rates were 94.7% and 77.8% for HN, 93.7% and 81.2% for CC, and 92.9% and 53.3% for ZC FPDs, respectively, indicating no clear difference in survival among the framework materials. The 5- and 10-year chipping-free rates were 94.1% and 82.8% for HN, 96.1% and 78.9% for CC, and 82.6% and 62.2% for ZC FPDs, respectively, indicating a difference between HN and ZC, and CC and ZC restorations. The 5- and 10-year success rates were 83.7% and 55.3% for HN, 86.5% and 51.4% for CC, and 68.9% and 30.2% for ZC FPDs, respectively, indicating a difference between HN and ZC, and CC and ZC restorations. The Cox regression model indicated framework material as an influencing risk factor for success, and this influence persisted when chipping was investigated. Compared with zirconia, the use of a metal alloy reduced the risk of chipping or the occurrence of complications by up to one-third., Conclusions: All FPDs showed high 5-year survival rates and acceptable 10-year survival rates with no strong differences among the materials. Higher success and chipping-free rates were observed for both HN and CC restorations compared with ZC restorations. Metal frameworks had a lower risk for complications or veneer chipping than zirconia frameworks., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Statement of Problem: Long-term data are sparse on the use of metal-acrylic resin implant-supported fixed complete dentures., Purpose: The purpose of this retrospective clinical study was to assess the prosthetic survival and complication rate in patients treated with metal-acrylic resin implant-supported fixed complete dentures (ma-IFCDs)., Materials and Methods: The patient record system at the Dental College of Georgia was searched from 2006 to 2020 to identify all patients treated with ma-IFCDs by the graduate prosthodontic and general practice residents during this time. Variables collected were date of delivery of the prosthesis, arch treated (maxilla, mandible), date of the last visit, status of the opposing arch (complete arch fixed implant-supported prosthesis, complete denture, removable implant-supported overdenture, teeth and removable partial denture, teeth and implants, teeth only), date of replacement, and reason for replacement. Reasons for replacement were grouped as fracture of the framework, implant loss, patient-related concerns, catastrophic acrylic resin fracture (judged to be beyond predictable repair by the clinician), and extensive occlusal wear (judged to have worn to the point of requiring replacement)., Results: A total of 84 arches in 55 patients who met the inclusion criteria were identified from the electronic health review. Of the 84 complete arch prostheses, 43 were maxillary and 41 were mandibular. The median follow-up time was 2.8 years (interquartile range [IQR] 0.95, 4.65). A total of 31 of the 84 arches were identified as having failed, requiring replacement. The most frequent reason for replacement was catastrophic fracture of the acrylic resin (61%), followed by excessive occlusal wear (19%). It was found that 13% of the failures were associated with patient-related concerns, and 7% with the loss of an implant. Survival rates were analyzed based on the opposing arch. The combined survival rate (Kaplan-Meier, log-normal modeling) for ma-IFCDs was 54% at 5 years (95% confidence interval [CI] 42%, 66%) and 32% at 10 years (95% CI 20%, 47%)., Conclusions: Mid- to long-term survival rates for ma-IFCDs are concerningly low. The findings suggest that the status of the opposing arch plays a role in the survival rate of ma-IFCDs. The most common complication was catastrophic fracture of the acrylic resin superstructure, followed by wear of the acrylic resin denture teeth., (Copyright © 2022 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to predict the risk of dental implant loss by clustering features associated with implant survival rates., Materials and Methods: Multiple clinical features from 8513 patients who underwent single implant placement were retrospectively analysed. A hybrid method integrating unsupervised learning algorithms with survival analysis was employed for data mining. Two-step cluster, univariate Cox regression, and Kaplan‒Meier survival analyses were performed to identify the clustering features associated with implant survival rates. To predict the risk of dental implant loss, nomograms were constructed on the basis of time-stratified multivariate Cox regression., Results: Six clusters with distinct features and prognoses were identified using two-step cluster analysis and Kaplan‒Meier survival analysis. Compared with the other clusters, only one cluster presented significantly lower implant survival rates, and six specific clustering features within this cluster were identified as high-risk factors, including age, smoking history, implant diameter, implant length, implant position, and surgical procedure. Nomograms were created to assess the impact of the six high-risk factors on implant loss for three periods: 1) 0-120 days, 2) 120-310 days, and 3) more than 310 days after implant placement. The concordance indices of the models were 0.642, 0.781, and 0.715, respectively., Conclusions: The hybrid unsupervised clustering method, which clusters and identifies high-risk clinical features associated with implant loss without relying on predefined labels or target variables, represents an effective approach for developing a visual model for predicting implant prognosis. However, further validation with a multimodal, multicentre, prospective cohort is needed., Clinical Significance: Visual prognosis prediction utilizing this nomogram that predicts the risk of implant loss on the basis of clustering features can assist dentists in preoperative assessments and clinical decision-making, potentially improving dental implant prognosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Statement of Problem: Current designs of fiber-reinforced composite (FRC) resin-bonded fixed dental prostheses (RBFDPs) have a limited lifespan, failing mainly through veneer-fiber delamination, debonding, and fracture., Purpose: The purpose of this in vitro study was to validate a new inlay-retained 2-unit cantilevered RBFDP with an optimized cavity and fiber layout proposed in a previous study by using simulated occlusal loading., Material and Methods: Two groups of specimens (n=20), 1 with and 1 without glass fibers, were used to test the influence of the cavity design and that of the fiber layout on their load capacity, respectively. The specimens without fibers were directly cut from a resin-ceramic block by using a computer-aided manufacturing system, while those with fibers were manually fabricated with unidirectional glass fibers and composite resin in a silicone mold. The specimens with and without fibers were attached to abutments made of the same resin-ceramic with a cyanoacrylate-based adhesive and a resin-based dental cement, respectively. An increasing compressive load was applied on the mesial fossa of the premolar pontic until failure. Cracking in the specimens during loading was monitored with a 2-channel acoustic emission (AE) system., Results: All the specimens without fiber reinforcement debonded from the abutments. Those using the optimized shovel-shaped cavity design had a mean ±standard deviation failure load (50.0 ±17.3 N) that was 193% higher than that of those with the conventional step-box design (17.1 ±6.2 N; P<.001). No significant difference was found between the groups for the mean number of AE events per specimen (step-box: 49 ±34 versus shovel-shaped: 63 ±34; P=.427), the mean amplitude of each event (58.4 ±1.3 dB versus 59.5 ±2.4 dB; P=.299), or the mean time to failure (283.2 ±122.3 seconds versus 297.5 ±66.7 seconds; P=.798). Between the groups of specimens with reinforcing fibers, the mean failure load of the conventional design was approximately half that of the optimized one. Again, no significant difference was found for the mean number of AE events per specimen (conventional: 28 ±18 versus optimized: 52 ±53; P=.248) or the mean amplitude for each AE event (64.9 ±4.2 dB versus 61.7 ±5.2 dB; P=.187). The connectors of 8 fiber-reinforced specimens with the conventional design fractured; the other 2 debonded from the abutments. Half of the shape-optimized fiber-reinforced specimens had fractured abutments, but the cantilevers remained intact, 4 specimens fractured at the connector, and only 1 debonded from its abutment., Conclusions: The shape-optimized 2-unit cantilevered FRC RBFDP had a higher load capacity than the conventional design., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

This study aimed to identify the ideal interimplant distance for optimum outcome on immediately loaded implant supported prosthesis. Hence this study was taken up to analyze the effect of varying interimplant distance on fracture resistance of implant supported provisional fixed dental prosthesis (FDP). A total of 24 bis-acrylate composite resin samples were prepared. Interimplant distance was present in the metal die for placement of dummy implants at distances of 14 mm, 21 mm, and 30 mm respectively. Wax-up for 3-unit, 4-unit, and 5-unit implant-supported provisional restoration was made. Silicone molds were used for making multiple interim prostheses using bis-acrylate composite material. All samples were subjected to fracture test in the universal testing machine with a crosshead speed of 1 mm/min. All samples were loaded with gradual force starting from 100 N until it fractured. The load was applied at the center of prosthesis. Data was analyzed by one-way analysis of variance and Bonferroni post hoc test. Mean fracture resistance of 3-unit provisional FDP at 14 mm of interimplant distance showed 1342.61 ± 179.15 N. Mean fracture resistance of 4-unit provisional FDP at 21 mm of interimplant distance showed 1420.44 ± 170.37 N. Mean fracture resistance of 5-unit provisional FDP at 30 mm of interimplant distance showed 791.61 ± 203.59 N. Both 14 mm and 21 mm of interimplant distance are suitable span lengths to be considered for the optimum outcome during immediately loading with implant-supported provisional restorations. Limitations of the study were that force application was static in nature and not dynamic and the arch form was not "U" shaped but longitudinal using Bis-Acryl material only with no cantilever. Future studies can be done to evaluate the fracture resistance of bis-acrylate material considering biomechanics and arch form of natural dentition. Distal cantilever should be considered along with different material for fabricating provisional restoration.

Objectives: To evaluate the effect of different cement types on the incidence of failure and loss of retention of zirconia and metal-ceramic single crowns (SCs) cemented on implant abutments., Methods: We placed 567 implant-supported SCs in 358 patients and retrospectively evaluated long-term retention for up to 12.8 years. The frameworks were made from metal alloy (n = 307) or zirconia (n = 260). SCs were cemented with permanent (glass-ionomer cement; n = 376) or semipermanent cement (zinc oxide non-eugenol cement; n = 191) on standardized (n = 446) or customized (n = 121) abutments. Kaplan-Meier curves were used to calculate the incidence of decementation. Differences between survival curves were assessed with log-rank tests. Cox-regression analysis was performed to evaluate multiple risk factors., Results: Of the 567 SCs, 22 failed because of technical complications and four because of implant loss. Loss of retention was observed in 50 SCs. Analysis revealed a 7% probability of loss of retention for zirconia and 16% for metal-ceramic SCs after 10 years (p = .011). After 5 years, loss of retention was higher for standardized abutments than for customized abutments (p = .014). The probability of loss of retention was higher with semipermanent than with permanent cement (p = .001). Cox-regression analysis revealed semipermanent cement as the only significant risk factor for SC failure (p = .026)., Conclusions: In contrast to semipermanent cement, permanent cement provides acceptable long-term retention of cemented implant-supported SCs. These possible positive effects of customized abutments have to be controlled with larger sample sizes., (© 2024 The Author(s). Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objective: To assess radiographic, clinical and patient-reported outcomes of single zirconia implant-supported crowns on titanium base abutments (TBA) over a 7.5-year period., Methods: Twenty-four patients received bone-level titanium implants and screw-retained zirconia implant crowns utilising TBA. Marginal bone level (MBL), clinical parameters (probing depth-PD, bleeding on probing-BoP, plaque control record-PCR), technical complications (USPHS criteria) and patient satisfaction were assessed at crown delivery (baseline), 1 year (FU-1) and at 7.5 years (FU-7.5) of follow-up., Results: Eighteen patients were available for re-examination at 7.5 years. The mean MBL at FU-7.5 (0.35 ± 0.20mm) did not significantly change compared to baseline (0.54 ± 0.39, p=.352) and to FU-1 (0.54 ± 0.45mm, p=0.524). From baseline to 7.5 years, the mean PD increased significantly, from 3.0 ± 0.6mm to 3.7 ± 0.8mm (p=0.005). However, BoP and PCR did not significantly change; (BOP: from 27.1 ± 20.7% to 25.0 ± 20.0%, p=0.498; PCR: from 11.1 ± 21.2% to 25.0 ± 25.1%, p=0.100). Nine patients presented with more than one bleeding site. This denoted a peri-implant mucositis prevalence of 50%, whilst none of the implants presented peri-implantitis. One incidence of minor and major ceramic chipping were reported on 2 out of the 18 crowns, resulting in a prosthetic survival rate of 94.4%. Seventeen patients were highly satisfied with their result., Conclusion: Single implant-supported zirconia crowns on TBA displayed: (i) minor number of technical complications, (ii) high prosthetic survival rate, (iii) stable marginal bone level and (iv) high patient satisfaction at 7.5 years., Clinical Implications: Titanium base abutments despite their high use in clinical practice, lacked medium- and long-term studies. The presented findings highlight their clinical performance at 7.5 years as they display satisfying radiographic, clinical and patient-related outcomes. TBA appear to be a suitable abutment choice for medium-term implant-supported restorations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: Conventionally and digitally manufactured removable complete dentures with different dentition forms were examined for manufacturing accuracy (trueness, precision), fracture forces under torsional loading and subsequent repairability., Methods: A total of 90 mandibular prostheses were manufactured. Ten were made using the injection molding technique and finished with prefabricated teeth. 40 bases each, were manufactured subtractively and additively. Digitally the prosthesis' dental arch was divided either into two quadrants or three sextants, or kept as full arch. Afterwards, ten additive and subtractive bases were finished with prefabricated teeth and ten of each with milled quadrants, sextants and full arches. After manufacturing, all specimens were rescanned for accuracy comparisons using the Root Mean Square (RMS). Lastly, all specimens were tested to failure under torsional loading., Results: Conventionally manufactured dentures showed the greatest deviation in accuracy. The type of base manufacturing did not determine the fracture resistance of the prostheses. The dentition form had a significant influence. While prefabricated teeth (86.01 ± 19.76 N) and quadrants (77.89 ± 9.58 N) showed a low fracture resistance, sextants (139.12 ± 21.41 N) and full arches (141.05 ± 17.14 N) achieved the highest fracture forces. Subtractive bases with prefabricated teeth or quadrants were assessed to be repairable, digital dentures with full arch were assessed as not repairable., Significance: The presented testing set-up is suitable to determine the fracture behavior of dentures rather than of standards. With the possibility of digital design and individual manufacturing, dentures' mechanical stability can be significantly increased, especially with suitable dentition forms., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: This prospective clinical trial evaluated the clinical performance of ceramic partial coverage indirect adhesive restorations (PCIARs) in posterior teeth luted with a light-cured composite resin., Methods: From April 2016 to January 2017, a total of 60 patients (27 males, 33 females; mean age: 42.2 ± 10.86 years old) received 83 glass-ceramic PCIARs (26 onlay, 57 overlay) made of IPS Emax CAD (Ivoclar Vivadent). All restorations were luted with a light-cured composite resin (Filtek Z250, 3 M ESPE) by two operators. Two independent calibrated examiners blinded to the operators performing the treatment evaluated the restorations at baseline, 1-year, and 5-year following FDI World Dental Federation criteria including esthetic, functional, and biological properties. Data were analyzed with the Friedman test and the Wilcoxon sign test (p < 0.05)., Results: None of the restorations failed due to fracture or retention loss. One restoration was clinically unsatisfactory because of secondary caries. Marginal staining (p:0.000), marginal adaptation (p:0.018) showed significant differences between 1-year and 5-year recall., Conclusions: The PCIARs demonstrated excellent clinical performance at 1-year period. The degradation parameters appeared as minor staining and minor irregularities after 5-year, without any affect on the clinical performance., Clinical Significance: Our findings provide evidence that the clinical performance of PCIARs luted with a light-cured composite resin was clinically acceptable after a five-year evaluation period. Due to secondary caries, only one restoration was considered clinically unsatisfactory., Clinicaltrials Registration Number: NCT04838483., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Statement of Problem: Studies investigating the survival of implant-supported crowns provided in a dental school setting are sparse., Purpose: The purpose of this retrospective study was to evaluate the success and reasons for failure of single unit and splinted implant-supported crowns provided in a dental school., Material and Methods: Using the axiUm dental management software program and paper charts, all single unit and splinted implant-supported crowns provided between September 1989 and January 2020 were included for evaluation. Success, survival, and failure were recorded as well as reasons for failure. A Kaplan-Meier survival estimate with an associated P value, a life table analysis, and a log-rank test comparing the survival of single unit and splinted implant-supported crowns were performed., Results: Over 30 years, 678 implant-supported crowns (586 single unit and 92 splinted) had been provided. Of these crowns, 17 (2.90%) single unit crowns and 5 (5.43%) splinted crowns failed, with most being prosthetic failures for both single units (64.7%) and splinted (80%), rather than biologic failures. A total of 371 single unit (63.3%) and 46 splinted (50.0%) implant crowns were a complete success, and 215 single unit (36.7%) and 46 splinted (50.0%) crowns survived but had some type of complication. The overall implant-supported crown survival rate was 96.8%. The survival distribution of the single unit and splinted implant-supported crowns was not statistically significantly different [χ2(2)=1.285, P=.257]., Conclusions: Both single unit and splinted implant-supported crowns had high success rates and showed similar survival rates. The most common causes of complications were also similar, with debonding and screw loosening of crowns being the most common complication for both single unit and splinted crowns., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)