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The reconstruction of alveolar ridge defects can be challenging, especially when the lesion is large, noncontained, and located in the esthetic region. The present report describes the guided bone regeneration (GBR) procedure and prosthetic rehabilitation of a severe perforation defect in the anterior maxilla. Clinical and radiographic evaluations of the lesion indicated an endodonticperiodontal origin, and biopsy results confirmed the absence of malignancy. GBR was performed with the use of cortical mineralized freeze-dried bone allograft (FDBA) combined with recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and a resorbable collagen membrane without the use of tenting or fixation screws. Six months after GBR, CBCT revealed adequate bone fill for the placement of 4.1 × 10-mm or 4.1 × 12-mm dental implants. The implant surgery was fully guided with a two-stage approach. After 10 months of healing, the implants were loaded with a screw-retained porcelain partial denture. The staged GBR approach, using a combination of FDBA, rhPDGF-BB, and a resorbable membrane without the use of tenting or fixation screws, resulted in significant bone fill, successful implant placement, and a functional and esthetic implant-supported prosthesis. [ABSTRACT FROM AUTHOR]

Purpose: To develop the most compatible cementation protocol for ensuring minimal residual cement and optimal retention of cement-retained implant-supported fixed dental prostheses. Materials and Methods: A total of 30 custom implant abutments and zirconia crowns with bilateral wings were prepared. Three cement types were used for cementation: noneugenol resin cement (Premier Implant Cement; Group IC), dual-polymerizing self-adhesive resin cement (SmartCem2; Group SC), and zinc oxide eugenol cement (Temp-Bond; Group TB; n = 30 per group). Three cementation methods were applied for each cement type, and the samples were divided into subgroups: (1) cement was injected using a graduated syringe (ICN, SC-N, and TB-N); (2) a cementation jig made with a silicone impression material and temporary resin material was used (IC-CJ, SC-CJ, and TB-CJ); (3) 3D-printed abutments were used as replicas for cementation (IC-3DP, SC-3DP, and TB-3DP). The amount of cement injected, surface area of the residual cement, and retentive strength were measured. Kruskal-Wallis and post-hoc Mann-Whitney tests were used for statistical analyses. Results: Excess cement was not observed when cementation jig or 3D-printed replicas were used. For IC and SC subgroups, non-use of these auxiliary tools resulted in significantly higher amounts of injected cement. The retentive strength differed significantly among the IC subgroups but not among the SC subgroups. The retentive strength of subgroups TB-N and TB-CJ was significantly higher than that of subgroup TB-3DP. Conclusions: To prolong the main purpose of each cement type, a cementation jig or 3D-printed replica is highly recommended regardless of the cement type. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the published literature on tooth--tissue supported removable partial dentures (RPDs) and determine the attachment system that provides the best clinical outcome. Materials and Methods: A comprehensive search of studies published up to November 2021 was performed in the PubMed/MEDLINE, Web of Science, and Cochrane Library databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The study protocol was approved and was registered in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42021268449). The PICO question was, "What is the best attachment system used in Kennedy class I and II removable partial dentures?" Results: The search identified 871 articles, of which 21 met the inclusion criteria. The evaluation period in the studies ranged from 3 to 282 months. A total of 1,357 patients were included, of which 526 used prostheses with attachments. The mini SG attachment (extracoronal) was the most commonly used attachment, and the survival rate ranged from 37% to 98.1% in 10 studies, with no significant differences between the systems. Among the 10 studies selected for quantitative analysis, the meta-analysis revealed an overall failure rate of 16.6% (95% CI: 10.4% to 25.4%) and heterogeneity of I² = 65.725 (q value: 26.258, P = .002). Conclusions: Clinical studies comparing different attachment systems for rehabilitation are lacking. Our findings suggest that attachment-retained RPDs have good retention and better esthetics than conventional RPDs, and the extracoronal attachment system is the most viable choice for treatment at the free end. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the masticatory efficiency of dentate and rehabilitated complete denture patients in various facial forms. Materials and Methods: A total of 60 subjects were selected for the study; 30 subjects belonged to the dentate group (D Group) and 30 subjects belonged to the completely edentulous group rehabilitated with conventional complete dentures (CECD Group). All patients were divided into a subgroup (brachyfacial, mesofacial, and dolichofacial facial forms) using facial index measurement and cephalometric analysis. After the subjects were divided into groups, masticatory efficiency testing was performed with spectrophotometric analysis using diluted expectorate of chewed natural beetroot test food (10, 15, and 20 strokes). The mean absorbance value was considered as the mean masticatory efficiency from which the average masticatory efficiency percentage was determined using a masticatory efficiency percentage equation and considered as the masticatory efficiency of that particular subject. Results: Statistical analysis revealed that in the D Group, brachyfacial subjects exhibited the highest masticatory efficiency (70.9 ± 12.64%), followed by mesofacial (60.6% ± 10.66%) and dolichofacial (34.3% ± 10.81%) subjects. In the CECD groups, the results for brachyfacial were highest (52.7% ± 8.11%), followed by the mesofacial (42.3% ± 6.52%), and dolichofacial (29.3% ± 7.76%) subjects. Conclusions: Along with other determinant factors, facial form plays an influential role on masticatory efficiency. Brachyfacial subjects exhibited the highest masticatory efficiency, followed by mesofacial and dolichofacial subjects in both study groups. [ABSTRACT FROM AUTHOR]

Purpose: To assess the survival of double-crown-retained implant-and-tooth-supported removable partial dentures (DCR-ITSRPDs), evaluate abutment survival, and identify first aftercare measures. Materials and Methods: The influence of various factors on the survival of the DCR-ITSRPDs and the abutments were observed in this retrospective and clinical follow-up study using the Kaplan-Meier estimate. In addition, the first-required aftercare measure for each prosthesis was evaluated. Results: In total, 47 DCR-ITSRPDs were investigated (mean observation: 4.3 ± 3.8 years; max: 14.3 years), 3 of which (6.4%) had to be replaced. The survival probability for DCR-ITSRPDs was 100% at 5 years and 75% at 10 years. A total of 297 abutments (120 natural teeth and 177 dental implants) were observed, 22 of which (7.4%; 6 teeth and 16 implants) failed. The survival probability for teeth was 90.2% at the 5- and 10-year mark; for dental implants, it was 90.4% at 5 years and 76.3% at 10 years. Conclusions: DCR-ITSRPDs are a successful and durable treatment option for patients with substantially reduced residual dentitions. Both prostheses and abutments show good survival times after 5 and 10 years in function. The patient-associated factors tested showed no influence on the survival of DCR-ITSRPDs and abutments. Peri-implant infection was the decisive factor for abutment loss; therefore, regular dental prophylaxis and examinations are of major importance. [ABSTRACT FROM AUTHOR]

The article discusses studies which show that full-ceramic prosthetic restorations for single crowns (SCs) and fixed dental prostheses (FDPs) are high quality and have a satisfactory survival rate comparable to porcelain-fused-to-metal (PFM). These studies include the survival outcome and complications in a retrospective clinical study of complete-arch fixed implant-supported prostheses (CAFIPs), the prevalence of prosthetic complications, and clinical performance of implant-supported FDPs.

Purpose: To compare the effect of taper, length, angle, and number of vertical axial walls on the retentive strength of a cemented crown on a partially customized hybrid abutment in the esthetic zone. Materials and Methods: A total of 35 metal copings were used and divided into two groups. One group had 30 copings cemented to their corresponding 8-degree tapered abutment with lengths from 3 to 8 mm, increasing in 1-mm increments (5 copings per length). The other group had the remaining 5 copings and consisted of a standardized metal coping that matched a hexagonal abutment with 3-mm vertical axial walls and the sequential removal of 1, 2, and 3 contiguous vertical axial walls. Dislodgment tests were performed for all copings in both groups. Maximum retentive forces were measured in retentive strength (kgF), with a conversion factor of 9.807 N = 1 kgF. Results: At each tapered abutment length, the retentive strength increased proportionally and was significantly different, ranging from 31.67 ± 4.10 kgF to 67.68 ± 11.22 kgF (F [5,24] = 20.46, P < .001). An unmodified hexagonal abutment demonstrated the highest retentive strength (70.15 ± 12.97 kgF). The sequential removal of 1, 2, and 3 contiguous vertical axial walls of the hexagonal abutment resulted in retentive strength values of 59.89 ± 10.06 kgF, 57.01 ± 9.62 kgF, and 55.99 ± 9.35 kgF, respectively, with no significant difference (P > .05) in strength. Conclusions: A partially customized abutment with vertical axial walls on one side and a profile reduction on the opposite side can provide comparable retention to cemented copings at one-third the length and at one-sixth the surface area of an 8-mm abutment with an 8-degree taper. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of using a customized xenograft shell with a 1:1 mixture of particulate xenograft and autogenous bone for the reconstruction of horizontally deficient anterior maxillary alveolar ridges. Materials and Methods: CBCT images of the atrophic maxilla of eight patients were acquired and generated into 3D models. The data were transferred to a 3D printer for fabrication. During the surgery, xenograft blocks were manually sliced and customized on the 3D-printed models into bone shells. Then they were fixed to the atrophic site, and the gap was augmented with a 1:1 mixture of particulate xenograft and autogenous bone. Results: Clinical assessment showed no adverse effects; however, one patient exhibited wound dehiscence. The mean difference between the preoperative and 6-month postoperative CBCTs showed a net average bone gain of 4.06 mm at 2 mm from the crest and 4.34 mm at 5 mm from the crest, which was statistically significant. On the other hand, a statistically significant graft resorption of 1.41 mm at 2 mm from the crest and 2.19 mm at 5 mm from the crest was found when the mean difference between the immediate and 6-month postoperative CBCTs was calculated. Conclusions: Within the limitations of the study, the use of xenograft shells as a barrier for maxillary alveolar ridge reconstruction is a predictable technique; however, further investigations regarding the required time for graft consolidation are required. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the correspondence between output from a new artificial intelligence tool (AIT) and clinician evaluation regarding the immediate loading suitability of dental implants based on insertion torque curves recorded during implant placement in an in vitro test. The secondary aim was to analyze peak insertion torque (PIT) and variable torque work (VTW) values of the implants. Materials and Methods: The study was performed with four different densities of artificial bone blocks of solid rigid polyurethane without a cortical layer. Five types of implants with different macrogeometries were used. A total of 140 implants (7 implants of each type in the four polyurethane blocks) were inserted. Immediately after implant placement, the insertion torque curves were classified by the operator as suitable (S) or nonsuitable (NS) for immediate loading. The same curves were then analyzed by the new AIT, which classified them as belonging to the "YES" or "NO" class. For each implant, PIT and VTW values were also recorded. Results: The correspondence between clinician and AIT evaluation was 99.3%, with only one false negative reported by the algorithm analysis. The AIT was found to have a sensitivity of 98.95%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 97.8%. Mean PIT of the whole sample was 34.19 ± 19.43 Ncm, while mean VTW was 2,266.89 ± 1,993.73 Ncm. Statistically significant differences were found between implant systems in the whole sample and according to density of the polyurethane block. Conclusions: The AIT showed a high level of accuracy in the prediction of immediate loading suitability of dental implants based on the provided insertion torque curves. All the implants used in the in vitro test achieved good levels of primary stability, except when inserted in the least-dense polyurethane block. Clinical studies conducted with larger samples and more clinicians are necessary to confirm these results. [ABSTRACT FROM AUTHOR]

The management of marked horizontal bone atrophy represents a critical challenge for traditional implantology procedures. For this purpose, clinicians have developed several protocols and procedures to allow the most suitable and accurate surgical and prosthetic implant rehabilitation. Despite the development of guided bone regeneration methods and the use of small-diameter implants, the rehabilitation of thin bone areas is a clinical dilemma for the medium- and long-term survival of implant-prosthetic therapies. This clinical case evaluates the use of wedge-shaped implants for the full-arch rehabilitation of an atrophic maxilla with a thin ridge. This treatment choice allowed a minimally invasive rehabilitation, avoiding regenerative bone surgery, while respecting biologic and prosthetic limits. Furthermore, evaluation of the implant stability quotient and marginal bone loss values during the first year of follow-up allowed analysis of the behavior of this rehabilitation in fullarch maxillary cases. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the impact of removable partial dentures (RPDs) on masticatory performance (MP) of partially edentulous subjects. Materials and Methods: Electronic database and hand searches were conducted to explore clinical trials reporting the evidence of the effect of metal- and acrylic-based RPDs on mastication. The validated objective and subjective measures of assessment of mastication were included. The article selection, data extraction, and assessment of risk of bias were conducted by two reviewers independently. Results: Out of 11,200 studies, 1 randomized controlled trial and 23 clinical trials met the inclusion criteria. Positive impact on different parameters of masticatory function after RPD treatment was reported in 14 studies. Subjective evaluation of chewing ability (CA) displayed an improvement in 83.3% of studies, while improvement was evidenced only in 69.5% of studies upon objective evaluation. Most studies reported data on free-end saddles. Of the 13 studies associated with bilateral free-end saddle dentures, 9 studies showed a positive effect on masticatory efficiency. Various factors were found to have an impact on the MP of RPDs. Conclusions: Subjective evaluation displays higher positive impact of RPDs in MP than objective evaluation. Assessment of patients' perspectives is important in clinical decision-making. Multiple factors affect the MP with RPD treatment. [ABSTRACT FROM AUTHOR]

Purpose: To assess the clinical concept of patient treatment with fixed tooth- and implant-supported restorations in a university-based undergraduate program after 13 to 15 years. Materials and Methods: In total, 30 patients (mean age 56 years) who had received multiple tooth- and implant-supported restorations were recalled after 13 to 15 years. The clinical assessment comprised biologic and technical parameters as well as patient satisfaction. Data were analyzed descriptively, and the 13- to 15-year survival rates for tooth- and implant-supported single crowns and fixed dental prostheses (FDPs) were calculated. Results: The survival rate of tooth-supported restorations amounted to 88.3% (single crowns) and 69.6% (FDPs); in implants, it reached 100% for all types of restorations. Overall, 92.4% of all restorations were free of technical complications. The most common technical complication was chipping of the veneering ceramic (tooth-supported restorations: 5.5%; implant-supported restorations: 13% to 15.9%) regardless of the material used. For tooth-supported restorations, increased probing depth = 5 mm was the most frequent biologic complication (22.8%), followed by endodontic complications of root canal-treated teeth (14%) and loss of vitality at abutment teeth (8.2%). Peri-implantitis was diagnosed in 10.2% of implants. Conclusions: The results of this study indicate that the clinical concept implemented in the undergraduate program and performed by undergraduate students works well. The clinical outcomes are similar to those reported in the literature. In general, the majority of biologic complications occur in reconstructed teeth, whereas implant-supported restorations are more prone to technical complications. [ABSTRACT FROM AUTHOR]

This article reports a case of maxillary rehabilitation with implant-supported fixed dental prostheses on six zirconia implants. A woman with impacted maxillary canines attended our dental clinic seeking a metal-free maxillary restoration. After the extraction of both impacted maxillary canines and the placement of autogenous bone graft, six two-piece zirconia implants with straight abutments were placed in the anterior maxilla. Two zirconia fixed dental prostheses with porcelain veneering, separated at the midline, were placed on these zirconia implants. The 10-year follow-up monitored the adequate evolution of both implants and restorations with no signs of peri-implant disease. [ABSTRACT FROM AUTHOR]

In our previous test model, the abutment teeth and the model base were printed with resin and bonded with a polyether material. Some abutment teeth were fractured during the mechanical load test. Therefore, the aim was to develop and evaluate a new model under mechanical loading until fracture with zirconia FPD frameworks. At a fracture load of up to 1,636 N, neither the artificial abutment teeth nor the base model fractured. Furthermore, the artificial abutment teeth did not detach from the base model. Therefore, the model should be suitable for mechanical testing of most ceramic-based framework materials for three-unit FPDs. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of immersion in water on deforma8on of maxillary denture bases created with CAD/CAM and heat-polymerized resin fabrica8on techniques under loading condi8ons. Materials and Methods: 2-mm-thick denture bases were fabricated using four techniques: CAD/CAM milling (CCM; Polywax PMMA blank, Yamachi PMMA disk Yamahachi Dental); 3D prin8ng (3DP; BV005, NextDent Base); compression molding (CM; Luciton 199, Dentsply Sirona); and injec8on molding (IM; Ivobase, Ivoclar; n = 5 per group). Three sta8c 49-N loads were applied perpendicular to each denture base, and the mean strain value (MSV) was recorded with strain gauges a[ached to the denture surface. The denture bases were stored at 37°C in dis8lled water for 14 and 28 days, and the MSVs under the same sta8c load were recorded. Results: The highest MSVs were observed at the posterior palatal seal, tuberosity, and labial notches of the dentures. The lowest MSVs were recorded for the CCM group and then the CM and IM groups. The highest MSVs were recorded for the 3DP group. No significant differences in regional MSVs (P > .05) were observed among the CCM, CM, and IM aber 14 and 28 days in water. Large devia8ons in MSVs were recorded for the 3DP group across the measurement sites aber water exposure (P < .05). Conclusions: CCM had the lowest denture deforma8on under sta8c loading. Aber immersion in water, the deforma8on changes under sta8c loading were stable for CCM, CM, and IM. However, varia8ons among the materials used in 3DP group influenced the mechanical performance and presented larger deformations. [ABSTRACT FROM AUTHOR]

Purpose: To determine the relationship between bone loss that occurs during the peri-implantitis process and variations in implant stability using resonance frequency analysis (RFA) measurement methods. Materials and Methods: Forty selftapping implants were placed in cow ribs, and study scenarios were established according to the affected implant side and bone loss depth (n = 10 implants per group): Case 1 = bone loss on one side (vestibular); Case 2 = bone loss on two opposite sides (buccal and lingual); Case 3 = bone loss on two adjacent sides (buccal and mesial); and Case 4 = foursided bone loss (circumferential). For each group of 10 implants, first a bone loss of 0 mm was evaluated, then 4-mm defects (simulating 1/3 of bone loss) were created and evaluated, and finally 8-mm defects (simulating 2/3 of bone loss) were created and evaluated. Osteotomy measurements were made with a periodontal probe. For each implant, RFA was measured by the same operator using the Beacon system (Osstell). Results: The initial implant stability quotient (ISQ) values of the 40 implants exceeded 70, reflecting an average of 73 in the buccolingual (VL) and 74.8 in the mesiodistal (MD) directions. ISQ measurements in the 10 implants in which bone dehiscence was performed on the vestibular aspect reflected a decrease in ISQ values as bone loss increased. When generating bone loss in two opposite sides (buccal and lingual), a greater decrease in ISQ values was observed when 2/3 of the implant were affected. The average VL ISQ measurement was less than 70 when at sites with 2/3 of bone loss. Conclusions: When bone loss occurs on only one side of the implant, the ISQ values decrease, but the implant maintains good stability. The same occurs when two opposite sides of the implant are affected, as the unaffected side has the least decrease in ISQ value. [ABSTRACT FROM AUTHOR]

Purpose: To compare the outcomes of immediate and delayed implant placement with bone-level tapered implants. Materials and Methods: In this post-market, multicenter prospective randomized controlled study with a primary endpoint of 1 year, 53 patients were randomized to receive either immediate implant placement (test group) or delayed implant placement (control group). The mean crestal bone level changes from implant loading to 12 months postloading were measured using standardized digital periapical radiographs. Changes in facial plate thickness (as measured on CBCT images), implant success and survival, implant stability, soft tissue changes, patient-centered outcomes, and adverse events were measured to assess outcomes between the test and control treatments at 12 months postloading. Results: Of the original 53 patients, 46 patients completed the study (23 in each group). Mean bone changes from loading to the 12-month follow-up were recorded with no statistically significant difference (P = .950) between the groups. The hypothesis was confirmed that immediate implant placement (test) in extraction sockets produces in similar outcomes as delayed placement (control). The test group was found to be similar to the control group (P = .022) in terms of mean changes in facial plate thickness. Implant survival and success were 95.8% in the test group and 92% in the control group. Stability in the control group was superior at the time of surgery, but there was no difference between the groups at implant loading, producing a nonsignificant P value of .563). Conclusions: This randomized controlled multicenter study showed comparable outcomes 1 year after prosthetic loading in the immediate and delayed implant placement groups. [ABSTRACT FROM AUTHOR]

Purpose: This prospective study evaluated the marginal bone level and periodontal parameters 6 years after placement of a convergent transmucosal neck implant. Materials and Methods: In total, 71 implants were placed in 60 patients. Of these, 52 implants were placed with a flapless technique and with the convergent neck exposed by 1 mm (early and delayed placement), while 19 implants were placed immediately after extraction (immediate placement). At least 3 months after insertion, customized abutments were applied and provisional resin crowns were cemented, while being careful to prevent any tissue compression. After 3 weeks, definitive metal-ceramic crowns were designed with the finish line at the soft tissue level and free from any compression. The implant survival rate at 6 years, marginal bone level changes (ΔMBL, mm), and Pink Esthetic Score (PES) were evaluated. Gingival phenotype was determined before the implant surgeries (thin/thick). A three-level hierarchical model was examined with a random intercept and random slope on follow-up time at the patient level and a random intercept at the implant level. Results: In all, 57 patients with 67 implants reached the 6-year point; 3 patients (5.0%) dropped out. The implant survival rate was 100%. ΔMBL from baseline to 24 months was 0.58 mm (95% CI: 0.48, 0.68), while ΔMBL from 24 to 72 months was 0.33 mm (95% CI: 0.19, 0.47). PES improved steadily from 6 to 48 months (+0.96; 95% CI: 0.71, 1.20), with overall stability at 72 months. No correlation between MBL and PES was observed. A significant association was found between thick gingival phenotype and less MBL variation. Greater implant diameter offered more MBL stability after 3 years but resulted in lower PES values. Conclusions: The use of convergent transmucosal neck implants placed with a flapless transmucosal approach with the crown margin positioned at the gingival level preserved marginal bone and guided gingival morphology for up to 72 months. The gingival phenotype was the parameter that most affected the soft and hard tissues. In the long term, implant placement timing was not related to MBL. [ABSTRACT FROM AUTHOR]

Objective: Ideal implant placement in atrophied posterior mandibular regions is challenging due to surgical difficulties and anatomical limitations. This study aimed to evaluate the use of allogeneic bone rings for vertical augmentation of atrophied posterior mandibular regions with simultaneous implants compared to autogenous bone rings, while avoiding donor site morbidity. Method and materials: A total of 24 vertically atrophied posterior mandibular segments (in 14 patients) were equally randomized into a study group in which mineralized freeze-dried allogeneic bone rings were used, and a control group in which autogenous bone rings with prepared implant osteotomies were harvested from the chin and used. All augmentation sites were prepared before inserting the bone rings. Implants were simultaneously inserted, fixing the bone rings into the native bone. All patients were clinically assessed after 1 week, 2 weeks, and 1 month. Crestal bone level was radiographically assessed after lweek, 6 months, and 3 months of prosthetic loading. Results: None of the 24 bone rings showed signs of implant or graft failure. There was no significant difference in the crestal bone level between the groups. Conclusion: Allogeneic bone rings can be a viable alternative to autogenous bone rings in augmenting the posterior aspect of the mandible, mitigating the concerns associated with donor site complications. [ABSTRACT FROM AUTHOR]

This assessment evaluated the clinical feasibility of using narrow-diameter implants to support a mandibular overdenture. Twelve patients presenting with an edentulous mandible were recruited from nine dental offices. Each patient received two to four implants in the mandible. The implants were placed without additional bone augmentation, and a total of 36 implants were placed. All sites achieved satisfactory crestal bone stability and soft tissue maintenance 1 year after the final prosthetic restoration. This investigation was supported by the Osseointegration Foundation, working in conjunction with the Zest Anchors implant company. There are three basic valuable activities that emerge from a professional foundation, which were reflected in this case study. They include disseminating information to practitioners, persuading young clinicians to become research investigators, and reaching out to patients in need of treatment who cannot afford it without a charitable opportunity. [ABSTRACT FROM AUTHOR]

Autotransplantation has been proven as a viable method of reconstructing missing teeth. While preparing the recipient site, the bone reduction location depends largely on the surgeon's experience. Inappropriate overpreparation can cause biologic and esthetic complications, such as buccal or lingual bone resorption. This paper provides an innovative method to aid clinicians in precisely preparing a recipient site with the assistance of medical image-processing software and a real-time navigation system. This case report presents the autotransplantation of a mandibular molar using this technique with good short-term (6 months) clinical outcomes, including radiographic bone fill, normal probing pocket depth, physiologic tooth mobility, acceptable gingival level, and satisfactory restoration. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate whether complete dentures (CDs) relined with long-term resilient liners (LTRLs) favor better masticatory function, satisfaction, and quality of life among completely edentulous patients compared to conventional CDs. Materials and Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and was registered in PROSPERO (the International Prospective Register of Systematic Reviews; CRD42021258700). The population, intervention, comparison, and outcome (PICO) purpose was to determine whether CDs relined with LTRLs favor better masticatory function, satisfaction, and quality of life among completely edentulous patients when compared to CDs. Searches were performed in the PubMed/MEDLINE, Embase, Scopus, Lilacs, BBO, and OpenGrey databases. Manual searches were also performed to identify additional primary studies. Results: Overall, 3,953 articles were found. After removing duplicates, reading the articles, and applying the inclusion and exclusion criteria, 15 articles were selected for qualitative analysis, totaling 422 patients with follow-up periods ranging from 1 week to 3 years. Among these, 8 studies assessed masticatory function using different methods, 2 assessed satisfaction, 1 assessed quality of life, and 4 assessed more than one outcome. Through qualitative analysis, LTRLs showed satisfactory results in most studies when compared to CDs in relation to masticatory function, satisfaction, and quality of life. Conclusions: LTRLs favor better masticatory function, satisfaction, and quality of life among completely edentulous patients compared to CDs. [ABSTRACT FROM AUTHOR]

Purpose: To assess the effectiveness of converting a conventional mandibular denture (CMD) into a single-implant mandibular overdenture (SIMO). Materials and Methods: Edentulous patients received a new CMD and were randomly assigned to the CMD or SIMO group. For SIMO patients, a midline early-loaded implant was inserted and incorporated into the CMD after 3 weeks. Patient satisfaction and oral health--related quality of life were assessed at baseline and up to 1 year. Regression models were constructed using Generalized Estimating Equation (GEE). Results: After 12 months, 32 patients were assessed (CMD: n = 17; SIMO: n = 15). Significant improvement was observed for the SIMO group compared to baseline measures. Conclusions: SIMO may be considered an effective alternative for patients unsatisfied with their CMDs. [ABSTRACT FROM AUTHOR]

Purpose: To identify pressure areas using an impression technique and to evaluate whether adjustment of dentures prior to installation can decrease ulcer frequency, reduce the number of adjustments, and improve satisfaction with treatment. Materials and Methods: A total of 50 complete denture users were selected and randomly divided into two groups. Pressure areas were identified in 25 subjects using the impression technique with fluid silicone, and the denture base in these areas was adjusted before installation. A total of 25 patients received new complete dentures without adjustments before installation. The number of ulcers observed was registered at 1, 7, 15, and 30 days after installation. Patient satisfaction was registered before installation and 1 month after installation. The number of necessary postinstallation adjustments was considered. Comparisons between the groups with respect to the number of ulcers and adjustments and patient satisfaction were performed using the Mann-Whitney test. Results: Identification of pressure areas reduced the number of ulcers after installation of the new prostheses. These results were observed in the 1- (P = .004) and 7-day (P = .002) adjustments for the maxilla and in all the adjustments for the mandible. The technique improved patient satisfaction (P = .031) and reduced the number of postinstallation adjustments (P ≤ .001). Conclusions: A reduction in the incidence of ulcers and number of adjustments and improvement in patient satisfaction could be observed with the use of the impression technique. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the long-term predictability of simplifying mandibular overdenture treatment using single-stage surgery and immediate prosthetic loading of a single implant to provide a more affordable treatment option. Materials and Methods: A total of 29 patients with a mean age of 68 years with problematic mandibular dentures were treated. A single implant (Brånemark System Mklll TiUnite, Nobel Biocare) was placed into the mandibular midline for primary stability. A ball attachment was placed, and the retentive cap was incorporated into the existing denture. The patients were recalled at 3 and 12 months and at 3, 5, 10, and 15 years. Clinical assessments, radiographs, and resonance frequency analysis were recorded. All complications, failures, maintenance, and reasons for failure to follow-up were noted. Visual analog scale (VAS) questionnaires were used to record patient satisfaction (ANOVA; P < .05). Results: One implant did not achieve sufficient primary stability to be immediately loaded and was treated with a two-stage delayed loading protocol. Of the 28 patients receiving immediately loaded implants, 14 patients were available for follow-up at 15 years. Implant survival remained at 100% throughout the study. Patient satisfaction was high, with a significant increase in all comfort and functional parameters (P values ranged from < .001 to .07) throughout the 15-year period. Conclusions: These 15-year results indicate that immediate loading of a single oxidized surface implant used to retain a mucosa-borne overdenture is a safe, reliable, and cost-effective treatment with high levels of patient satisfaction long term. [ABSTRACT FROM AUTHOR]

Traditionally, metal-ceramics, metal-reinforced acrylics, and--more recently--full-contour or layered zirconia have been the materials of choice for definitive fixed implant-supported rehabilitations. Polymethyl methacrylate (PMMA) is commonly used in implant dentistry for the fabrication of implant-supported interim prostheses and as milled or 3D-printed prototypes. This article describes a novel protocol to prosthetically restore a completely edentulous patient following a digital workflow, with fixed, screw-retained, implant-supported prostheses fabricated from CAD/CAM milled PMMA, with no metal substructure. After a 2-year follow-up in terms of esthetics, phonetics, function, and biologic tissue response, the outcome remains functional and free of mechanical, biomechanical, or biologic complications. The aim of this article is to illustrate the feasibility of using milled PMMA as a viable definitive prosthetic material for the fixed implant rehabilitation of edentulous patients. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the marginal integrity of three inlay-retained fixed dental prosthesis (IRFDP) designs fabricated using monolithic zirconia. Materials and Methods: In total, 30 IRFDPs were fabricated using 4-YTZP monolithic zirconia and randomly divided into three groups according to the cavity design. Groups ID2 and ID1.5 received an inlay cavity preparation, which includes a proximal box and an occlusal extension with a depth of 2 mm or 1.5 mm, respectively. Group PB received a proximal box cavity preparation without an occlusal extension. The restorations were fabricated and cemented using a dual-cure resin cement (Panavia V5) and subjected to an equivalent of 5 years of aging. The specimens were evaluated under an SEM to measure marginal continuity before and after the aging process. Results: During the whole 5-year aging process, no specimens showed signs of cracking, fracture, or loss of retention in any restorations. In the SEM analysis, most marginal defects observed in the restorations were areas of microgaps at the tooth/ cement interface (TC) or zirconia/cement interface (ZC), resulting in loss of adaptation. There was a significant difference between the groups after the aging process at both the TC (F = 4.762, P < .05) and ZC (F = 6.975, P < .05), with Group ID2 presenting the best performance. There was a significant difference between TC and ZC in all groups (P < .05), with ZC presenting more gaps in all groups. Conclusions: Inlay cavity designs including a proximal box and an occlusal extension exhibited better marginal stability than a proximal box without occlusal extension. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate and compare the difference in retention between implant-supported restorations with and without surface modification of the implant abutments. Materials and Methods: A total of 30 patients with singletooth implants were restored with cement-retained (Multilink N, Ivoclar) restorations using titanium base abutments (Variobase, Straumann) and randomly assigned surface modifications. Group 1 used nonmodified abutments, group 2 used sandblasted abutments, and group 3 used sandblasted abutments followed by an application of metal primer. All patients were recalled for a baseline examination 6 months after crown placement. The pull-out strength and intergroup distribution of mean pull-out strength were assessed. To assess differences between the three groups, intergroup statistical comparison of continuous variables was done using one-way ANOVA with Tukey correction for multiple group comparisons. Results: The results of the intergroup mean pull-out strength distribution revealed that the distribution of mean ± SD pull-out strength in group 1, group 2, and group 3 were 220.79 ± 94.23, 488.64 ± 84.12, and 705.46 ± 112.75 Ncm, respectively. Conclusions: Sandblasting followed by the application of metal primer produced the highest retention of porcelain-fused-to-metal (PFM) crowns to titanium base abutments, followed by sandblasting alone, with the least retention being observed with no surface treatment. [ABSTRACT FROM AUTHOR]

Purpose: To retrospectively determine the cumulative survival rate (CSR) and marginal bone level change (ΔMBL) around novel hybrid design tissue-level (TL) dental implants that support multiple-screw-retained restorations. Materials and Methods: Implant CSRs were analyzed at the implant and patient level using Kaplan-Meier estimates. ΔMBL was measured by comparing the periapical loading and follow-up visit radiographs using an improved standardized digital methodology based on image gray levels. ΔMBL outcomes were subject to linear mixed regression to identify potential risk factors. Results: A total of 301 TL implants in 69 patients with an average age of 62.6 ± 11.7 years (range: 36 to 87 years) at the time of implant placement were considered for the analysis. All 301 implants were successfully restored and loaded. The 54-month CSRs at the implant and patient levels were 98.9% (95% CI: 96.7 to 99.6) and 95.3% (95% CI: 86.1 to 98.5), respectively. ΔMBL after a mean follow-up of 22 ± 10.7 months after loading was 0.00 ± 0.57 mm. None of the implant sites showed marginal bone loss exceeding 1.5 mm. Multivariate regression analysis revealed a significant association between ΔMBL and the loading protocol (P = .027) but not between ΔMBL and age or transgingival height. Conclusions: The high CSRs and stable peri-implant marginal bone levels support the use of recent TL implants, which have a hybrid design inherited from the bone-level implant-abutment connection, as a suitable treatment option for restoring partially or fully edentulous patients with a good mid-term prognosis. These results should be complemented by further prospective studies in a real-world multicenter private practice setup that represents the daily realities of implant treatment. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the available evidence and assess the effect of different implant coatings on healing outcomes. Materials and Methods: Using the PICOS strategy, a structured question was formed. A protocol was agreed upon and registered with PROSPERO (no. CRD42022321926). The MEDLINE, Embase, Cochrane Database of Systematic Reviews, Scopus, Web of Science, Pubmed, and ScienceDirect databases were searched using a structured strategy. Study selection was independently carried out in duplicate, first by title and abstract, then by full-text assessment. Quality and risk of bias were independently assessed in duplicate using AMSTAR 2 and ROBIS. Data extraction was independently undertaken in duplicate using a predefined extraction form. Results: The search yielded 11 systematic reviews for inclusion. The most commonly assessed coatings were based on calcium phosphate--including hydroxyapatite (HA), brushite, and bioabsorbable nano-HA--followed by bisphosphonate, then bioactive glass coatings. Included reviews most frequently assessed marginal bone loss (MBL), bone-to-implant contact (BIC), and survival/success rates. There was considerable heterogeneity and small sample sizes. The quality assessment suggested low confidence in the reviews and high risk of bias. Conclusions: The included reviews provide weak evidence that implant coatings improve osseointegration and reduce MBL following implant placement. There was weak evidence for progressive complications for calcium phosphate coatings. Further research and long-term multicenter controlled clinical trials with improved standardization and control of bias are required to better understand the effects of coating implants. [ABSTRACT FROM AUTHOR]

Purpose: When carrying out prosthetic rehabilitation of edentulous and partially edentulous patients, great attention is paid to the personal attitude of the patients, their satisfaction with oral health and psychosocial interaction due to tooth loss, as well as the treatment of the resulting disorders. This attention has led to the development of various instruments for examining the quality of life related to oral health. The aim of this study was to develop and validate a reliable instrument in the Serbian language suitable for measuring oral health-related quality of life in patients who have been rehabilitated with complete or partial dentures. Мaterials and Methods: The study was unicentric and cross-sectional, and assessed the reliability and validity of a newly developed instrument for measuring the oral health-related quality of life in denture wearers (OHRQoL-DW). It was conducted on a sample of 200 adults from Serbia, wearers of various types of dentures, with a mean age 66.9 ± 10.3 years and male/female ratio of 86/114 (43%/57%). Results: The definitive version of the OHRQoL-DW scale with 28 items showed very good reliability, with Cronbach’s alpha = 0.938. Good temporal stability of the questionnaire was demonstrated, and satisfactory results were obtained for divergent and convergent validity tests. Exploratory factorial analysis revealed four domains of oral health-related quality of life in denture wearers: physical, psychosocial, environmental and aesthetic. Conclusions: The OHRQoL-DW scale is a reliable and valid generic instrument for measuring the oral health-related quality of life in patients wearing dentures, which is one of the most important outcomes of oral health in prosthetic treatment. [ABSTRACT FROM AUTHOR]

Purpose: The objective of the present systematic review and meta-analysis was to assess randomised controlled trials (RCTs) which assessed the efficacy of mini dental implants (MDIs) and standard-diameter implants (SDIs) in retaining mandibular overdentures (MO). Materials and Methods: The focused question was “Is there a difference in the mechanical stability between MDIs and SDIs in retaining MO?” Indexed databases were searched up to and including November 2023 using different keywords. Boolean operators were used during the search. The literature was searched in accordance with the PRISMA guidelines. The PICO characteristics were: patients (P) = individuals with complete mandibular dentures requiring dental implants; Intervention (I) = placement of MDIs under mandibular dentures; Control (C) = placement of SDIs under mandibular dentures; Outcome (O) = comparison of stability between MDIs and SDIs in supporting mandibular dentures. Only RCTs were included. Risk of bias (RoB) was assessed using the Cochrane RoB tool. Results: Five RCTs were included. The numbers of participants ranged between 45 and 120 edentulous individuals wearing complete mandibular dentures. The mean age of patients ranged between 59.5 ± 8.5 and 68.3 ± 8.5 years. The number of MDIs and SDIs ranged between 22 and 152 and 10 and 80 implants, respectively. The follow-up duration ranged between one week and 12 months. Three RCTs reported an improvement in the quality of life (QoL) of all patients after stabilisation of mandibular dentures using MDIs or SDIs. In one RCT, peri-implant soft tissue profiles were comparable between MDIs and SDIs at the 1-year follow-up. The implant survival rate was reported in two RCTs, which were from 89% to 98% and 99% to 100% for MDIs and SDIs, respectively. All RCTs had a low RoB. Conclusion: Mini dental implants represent a viable alternative to traditional standard-diameter implants when seeking optimal retention for mandibular overdentures. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the impact of photodynamic therapy (PDT) on the oral health-related quality of life (OHRQoL) among denture stomatitis patients with implant overdenture prostheses (IODs). Materials and Methods: The patients were recruited from a specialist dental practice according to selection criteria. The Candida spp. were identified and confirmed by the microbiological culture technique. Candida counts were estimated as colony-forming units (CFU/ml) at baseline, 15, 30, and 60 days. PDT was carried out twice a week with 72 h intervals for a period of 4 weeks. A structured questionnaire was used for data collection. It included the demographic details of the patients, including age, gender, education, marital and socioeconomic status (SES), oral habits, and smoking status. In addition, the Oral Health Impact Profile-EDENT (OHIP-EDENT) scale was added to assess the OHRQoL of all patients before and after PDT treatment. The data were analysed using descriptive statistics, the t-test and the Shapiro-Wilk test; statistical signifcance was set at p < 0.05. Results: At baseline, the overall mean Candida CFU/ml were quite high in the implant overdenture (IODs) samples, 37.12 ± 15.8, as compared to palatal mucosa samples with 5.1 ± 2.3. After PDT treatment, a statistically significant reduction was noted in the mean Candida CFU/ml on both surfaces at all follow-up visits. It was observed that all domains of OHIP-EDENT except for physical disability and handicap showed statistically significant improvement in mean scores after PDT treatment. FL, P1, P2, D2, and D3 had statistically significant mean score improvements of 2.2, 3.1, 2.2, 1.4, and 0.7, respectively. Furthermore, after PDT treatment, the total OHIP-EDENT score showed a statistically significant improvement of 11.6. Conclusion: PDT treatment has a positive impact on the OHRQoL for patients with denture stomatitis. It can be used as an effective treatment option for the treatment of denture stomatitis in IOD patients. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the peri-implant parameters of immediately placed and loaded mandibular overdentures over a 5-year follow-up period. Materials and Methods: All subjects who had been advised and planned for two-implant mandibular overdenture treatment were included in this study. The peri-implant parameters –including plaque index (PI), bleeding index (BI) and peri-implant pocket depth (PIPD) as well as marginal bone loss (MBL) – were assessed. In addition, prosthodontic parameters including abutment-, implant- and denture-related complications were assessed. Patients were evaluated at follow-up visits, scheduled at 1, 12, 24, 36, 48, and 60 months. The data distribution was analysed with the Shapiro-Wilk test. Data within follow-up categories were compared using ANOVA and the Tukey-Kramer test. A p-value < 0.05 was considered statistically significant. Results: Among the 32 participants, 19 were males and 13 were females, with a mean age of 60.5 ± 7.33. The mean plaque index (PI), bleeding index (BI) and peri-implant pocket depth (PIPD) varied over time. However, no statistically significant difference was observed in the plaque index, bleeding index and peri-implant pocket depth over time (p > 0.05). The mean value at baseline was found to be -0.9 ± 0.3. The values increased over time, with the highest value observed at 60 months 2.6 ± 0.7, which was statistically significant (p < 0.001). Conclusion: Immediately placed and loaded mandibular implant overdentures using two un-splinted implants with locator attachments showed acceptable PI, BI and PIPD at the 5-year follow-up. Statistically significantly greater marginal bone loss was observed from baseline to follow-up, but it was within acceptable limits. A moderate number of restorative and abutment complications were observed during the follow-up of IODs. [ABSTRACT FROM AUTHOR]

The use of conventional scan bodies (SBs) with an intraoral scanner (IOS) to capture the position of a complete arch of dental implants has proven to be challenging. The literature is unclear about the accuracy of intraoral scanning techniques using SBs that are connected vertically to multiunit abutments (MUAs) for numerous adjacent implants in the same arch. Recently, there has been a paradigm shift from vertical SBs to horizontal SBs, which are positioned perpendicular to the long axis of the MUAs. Most IOSs available today can capture these horizontal SBs, called scan gauges (SGs), with better accuracy and consequently acquire the position of multiple adjacent implants using an effective scan path, thus reducing stitching and the number of images. The key to implementing this novel technology is to strategically arrange the SGs to optimize horizontal overlap of multiple adjacent SGs without touching each other. By superimposing two high-resolution intraoral scans of the SGs, an artificial intelligence (AI) algorithm is employed to produce a calibrated digital best-fit model on which a passive complete-arch prosthesis can be designed and fabricated. The advantages and disadvantages of SBs and SGs are discussed, and a case report using a digital workflow is presented. [ABSTRACT FROM AUTHOR]

The present study assessed the impact of a fixed prosthetic rehabilitation on masticatory function in patients diagnosed with stage IV periodontitis. Eligible participants were adults in need of complex rehabilitation due to masticatory dysfunction. Masticatory function was evaluated using the two‐ colored chewing gum mixing ability test (VOH) at the diagnostic phase (T0), 1 week after delivery of the prosthetic prototype (T1), and 1 week after delivery of the final prosthetic solution (T2). Ten subjects were treated with a fixed prosthesis following periodontal and implant surgery using an individualized, fully digital workflow. Full-mouth plaque and bleeding scores, pocket depth, and clinical attachment level improved significantly. VOH was 0.472 ± 0.168 at T0, 0.358 ± 0.166 at T1, and 0.250 ± 0.123 at T2. A significant improvement in VOH was observed from T0 to T1 (difference: –0.114; 95% CI: –0.199 to –0.029; P = .014) and from T1 to T2 (difference: –0.108; 95% CI: –0.200 to –0.015; P = .027). From T0 to T2, VOH increased by 44.3%. Self-perceived assessment of masticatory function also improved from T0 to T2 (P = .002). The fixed prosthetic rehabilitation in patients with stage IV periodontitis allowed for a significant improvement in objective and subjective measurements of masticatory function. [ABSTRACT FROM AUTHOR]

The aim of this morphometric study was to precisely determine the 3D characteristics of the root complex of the posterior dentition. Extracted and well-preserved permanent posterior teeth were included in this analysis and grouped based on tooth type and arch location. All teeth were digitally scanned. Morphologic and dimensional features of the root complex were assessed, including length and surface area of the root trunk and individual roots, width of root concavities (RC), and furcation entrance, when present. A total of 240 posterior teeth comprised the study sample. The root complex of multirooted maxillary first premolars presented with a long root trunk (10.49 mm), representing 65.52% of the surface area, and two short roots comprising the remaining 34.8% of the surface area. Root trunks of mandibular molars were an average of 0.8 mm shorter than their maxillary counterparts. Class III furcation involvement is expected in all maxillary and mandibular molars, as well as multirooted maxillary first premolars, after 4.80 mm and 10.49 mm of clinical attachment loss, respectively. RCs were a common finding among the evaluated dentitions. The root complex morphology varies among the maxillary and mandibular posterior dentition. RCs are highly prevalent in both maxillary and mandibular dentition. The findings derived from this study can be utilized in daily clinical practice for the adequate management of posterior dentition and serve as a reference for future investigations in dental anatomy and digital technology. Also, these findings can guide the industry into creating and redefining tools that adequately adapt to the anatomical characteristics and variations of the specific tooth type. [ABSTRACT FROM AUTHOR]

Purpose: To determine the influence of partial edentulous distal extension and the use of removable partial dental prostheses in partially edentulous areas on the force exerted on the anterior teeth. Materials and Methods: A total of 83 volunteer patients participated in this study. The occlusal force was measured using an occlusal force measuring sheet in the patient's mouth. The occlusal forces and ratios were compared using the Wilcoxon signed-rank test (P < .05). Results: The force exerted on the anterior teeth increased significantly as the number of remaining teeth decreased in an edentulous distal extension. The force exerted on the anterior teeth decreased significantly with the use of a removable partial dental prosthesis. Conclusions: In a clinical setting, when the number of remaining teeth in a partial edentulous distal extension decreases, the burden on the anterior teeth increases. Our findings suggest that, for patients with partial edentulous distal extension, using a removable partial dental prosthesis is effective in preserving the residual anterior teeth by reducing excessive force. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the mechanical properties of acrylic resins at different aging times for denture bases manufactured using the conventional method, microwave processing, milling, and 3D printing. Materials and Methods: A total of 160 rectangular samples (64 × 10 × 3.3 ± 0.03 mm) were prepared, divided among the four main resin groups, and subdivided into four analysis times (T0, T1, T2, and T3), resulting in 10 samples per subgroup. The samples were stored in distilled water at 37° ± 2°C for 24 hours (T0), then subjected to thermocycling at temperatures of 5° ± 1°C and 55° ± 1°C in different numbers of cycles: 5,000 (T1); 10,000 (T2); and 20,000 (T3). The mechanical properties evaluated were surface microhardness, flexural strength, and modulus of elasticity. Statistical differences between resin groups and aging time were evaluated using two-way analysis of variance (P < .05). Results: The 3D-printed resin showed the significantly lowest values of microhardness, flexural strength, and modulus of elasticity compared to other resins (P < .001). Conclusions: The CAD/CAM--milled denture resin showed mechanical properties similar to those of traditional resins (conventional and microwave-processed). The 3D-printing resin did not show adequate mechanical properties for long-term clinical use. Despite this, new studies are developing better properties of this resin for long-term use. [ABSTRACT FROM AUTHOR]

Digital or CAD/CAM workflows and protocols are being increasingly utilized because of their improved efficiency and reproducibility. For the fabrication of complete dentures, digital workflows can reduce treatment time and clinical visits while enhancing the reliability and reproducibility of the laboratory phase and materials. However, establishing centric relation (CR) and vertical dimension of occlusion (VDO) in a reproducible way is still a challenging step for complete denture fabrication in both analog and digital workflows. This clinical report describes a digital workflow using an individualized gothic arch tracing device (GATD) with open-source software for the fabrication of complete dentures. With this workflow, clinicians can offer customized solutions according to patient rehabilitation, with good reproducibility using gothic arch tracing to be implemented in the digital workflow. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study which evaluated the effectiveness and accuracy of a proposed duplication technique in terms of one- and three-dimensional discrepancies between an original abutment and polyurethane duplicates obtained through a conventional workflow in single-implant rehabilitation. Topics covered include master cast with the Giroform System, abutment duplication and the influence of duplication on crown marginal and internal adaptation.

Purpose: To evaluate the effect of adding tea tree oil to denture liners on Candida albicans and bond strength to the acrylic denture base. Materials and Methods: Disc-shaped specimens were fabricated from silicone-based resilient liner (Tokuyama, Molloplast), acrylic-based hard liner (GC Reline), and acrylic-based soft liner (Visco-gel). Tea tree oil (TTO) was incorporated into the liners at varying concentrations (0% [control], 2%, 5%, 8%). C albicans were counted by viable colony count, and optical density (OD) was measured with a spectrophotometer. The tensile strength to heat polymerized acrylic denture base was measured in a universal testing machine. The compliance of the data to the distribution of normality was evaluated using the Shapiro Wilk test. Two-way ANOVA, Bonferroni correction, and paired sample t test were performed (α = .05). Results: The addition of TTO into liners provided a significant decrease in the OD values (P < .001). The control groups of the liners presented the highest colony counts, whereas increasing TTO decreased the results (P < .01). According to tensile bond strength test, 8% TTO addition resulted in a significant decrease for Tokuyama (P < .01) and Molloplast liners (P < .05), while 2% TTO resulted in significance for GC Reline (P < .001). Conclusions: Denture liners containing increasing percentages of TTO presented lower amounts of C albicans colonies and decreased bond strength to the denture bases. When using TTO for its antifungal properties, the amount added should be carefully selected because the tensile bond strength may be affected. [ABSTRACT FROM AUTHOR]

The article discusses a study which compared the fit and fracture load of temporary fixed partial prostheses fabricated by means of a conventional direct technique, milling or 3D printing. Topics covered include the strength of the fixed dental prostheses, the values of the fracture test, and the maximum mastication forces in the molar region.

Purpose: To compare the marginal and internal fit of monolithic zirconia (MZ) 3-unit fixed dental prostheses (FDPs) fabricated using two CAD/CAM workflows: full-chairside (FCH) and lab (LAB). Materials and Methods: The right maxillary first premolar and first molar were prepared for MZ 3-unit FDPs on a typodont. CEREC Primescan digiOzed the typodont model 15 Omes. A total of 30 FDPs was fabricated using two processes: FCH (n = 15) and LAB (n = 15). FCH and LAB FDPs were designed using CEREC SW 4.5.1 and Exocad and milled using CEREC MC X and Zirkonzhan 600/V3, respecOvely. A fast-sintering protocol was used in both groups. A dual-scan technique was used to assess the cement space at the occlusal surface (OC), axial wall (AX), and margin (MA). StaOsOcal analysis of the results was performed using univariate ANOVA with Scheffè post hoc test (a = .05). Results: Measurements in the FCH and LAB groups were within the clinically acceptable marginal and internal fit. The fit of FCH FDPs at MA, AX, and OC was 77.50 ± 29.99 μm, 99.67 ± 21.58 μm, and 150.03 ± 30.78 μm, respecOvely. The fit of LAB FDPs at MA, AX, and OC was 100.27 ±27.06 μm, 116.53 ±17.90 μm, and 142.30 ±19.00 μm, respecOvely. The difference between the two groups was not staOsOcally significant. Conclusions: MZ 3-unit FDPs fabricated using FCH have clinically acceptable marginal and internal fit. This result verifies the ability of FCH workflow to fabricate MZ mulOunit FDPs in a single visit. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the precision and efficiency of a novel guide system for single implant placement in the mandibular symphyses and to evaluate whether the outcome is affected by the level of operator experience. Materials and Methods: A total of 90 implants were placed in three different mandibular cast types (Cawood and Howell class III, IV, and V). For each model, a complete denture was 3D printed. A polyether ether ketone rail with a guide sleeve was embedded in the middle of the denture. To determine the ideal implant position, the sleeve could be moved in a buccolingual direction. Adjustment of implant angulation was possible, and an angle correction of 0, 12, or 24 degrees was available. A total of 30 clinicians were divided into three groups: group 1 (experienced, n = 10), group 2 (beginner, n = 10), and group 3 (inexperienced, n = 10). Each clinician was asked to plan and perform a guided flapless implant placement in the mandibular symphysis. Two preoperative CBCT scans were taken; the first was to verify the planning, and the second was to adjust the planning if needed. Finally, a postoperative CBCT scan was taken to compare the planning to the final implant position. Results: Based on the first CBCT, the clinicians adjusted their planning by an average of 1.66 ± 1.65 mm coronally, 2.41 ± 2.44 mm apically, and by a mean angular correction of 6.08 ± 0.77 degrees. After implant placement, the mean deviation from the planned implant position was 0.87 ± 0.58 mm at the coronal aspect and 0.98 ± 0.64 mm at the apical aspect. The mean angular deviation was 6.05 ± 0.71 degrees. Overall, there were no significant differences in coronal and apical deviation (P > .05) based on the level of experience. In terms of angulation, a significant difference was found in both planning (P = .049) and placement (P = .038) between beginners and experienced clinicians. Conclusions: Guided implant placement of a single implant in the mandibular symphysis using a removable denture with guide sleeve had an acceptable level of accuracy. Clinicians with limited experience spent more time on the procedure, resulting in less angular deviation during implant planning and placement compared to experienced clinicians. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the possible antimicrobial activity of glycine air polishing by comparing peri-implant microbiota before and after treatment. Materials and Methods: A total of 15 patients who received implant-supported full-arch fixed rehabilitations were included. After prosthesis removal (T0), Plaque Index (PI), probing depth (PD), and bleeding on probing (BOP) were recorded. In each hemiarch, the implant with the highest PD score was selected for microbiologic sample collection from the peri-implant sulcus (T0). All patients received two different hygienic protocols (randomly administered, one per each hemiarch): glycine air-polishing (G) and cleansing with cotton pellets soaked in saline (C). At 7 days (T1) and 3 months (T2) after the intervention, PI and BOP were recorded, and new microbiologic samples were taken. Traditional polymerase chain reaction (PCR) and quantitative PCR real-time were employed for microbiologic analysis to investigate how the presence of different bacterial species varied according to the hygienic treatment performed. Results: Treatment G provided a significantly higher PI score reduction around implants compared to treatment C (P = .015). No statistical difference was found in the microbial population around G and C implant sites, with Tannerella forsythia being the most commonly detected bacterial species in both G and C groups. No statistical differences were found between the antimicrobial activity of treatments C and G. Conclusions: Glycine powder air polishing is a valid method for professional hygienic care of implants and was more effective in PI reduction compared to the control treatment. However, its antimicrobial efficacy cannot be confirmed by the outcomes of the present study. [ABSTRACT FROM AUTHOR]

Purpose: To review experimental peri-implantitis studies using rat models and summarize different peri-implantitis induction techniques and evaluate their effectiveness. Materials and Methods: Electronic searches were conducted by two independent examiners to address the following issues. Meta-analyses explored the marginal bone loss (MBL) of four types of peri-implantitis induction methods in rats. The detailed induction tactics--such as the implant design, implant size, surgical process, time cost, induction methods, and endpoint measurements--were summarized. Results: Of the 18 included studies, 38.9% of the studies placed implants at the maxillary first molar, and 44.4% placed them at the alveolar ridge region anterior to the maxillary first molar. As for the induction method, the numbers of published studies on ligature methods, bacterial inoculation, and bacterial lipopolysaccharide inoculation were equally high among all selected studies. The total implant survival rate at the end was 160 out of 213 implants (75.11%). Eight studies with high pooled heterogeneity (I2 = 98, P < .01) in the meta-analysis reported an overall MBL (µ-CT) of 0.47 mm (95% CI = 0.14 to 0.81). A subgroup analysis estimated an MBL of 0.31 mm (95% CI = 0.12 to 0.50) for bacterial inoculation and 0.66 mm (95% CI = 0.07 to 1.26) for the ligature method. Histopathologic analysis revealed that peri-implantitis in rats was similar to peri-implantitis lesions in humans. Conclusions: Implant placement at the maxillary first molar with bacterial inoculation and the silk ligature method to build peri-implantitis rat models is reliable to use for research on peri-implantitis. [ABSTRACT FROM AUTHOR]

This study retrospectively evaluated the influence of prosthetic features on marginal bone level changes around bone-level implants with an external hex connection. A total of 100 patients with 166 implants and cemented crowns were included. Demographic and clinical data were collected. Prosthetic features were radiographically evaluated, including emergence angle (EA), emergence profile (EP), crown-implant ratio (CIR), and abutment height. Marginal bone levels were measured on intraoral radiographs taken at baseline and after at least 1 year. The correlation between prosthetic features and marginal bone loss (MBL) was then investigated. The mean follow-up time was 43.94 months. Implant length varied between 5 and 13 mm. The mean height of the abutments used was 1.55 mm. EA measured an average 30.62 degrees (± 13.20) mesially and 29.45 degrees (± 13.07) distally. The CIR was 0.99 (± 0.26). The mean MBL was 0.19 mm on the mesial side and 0.20 mm on distal side of the implants. Significant positive associations emerged between MBL and implant length (P < .005) and with EA (P < .05). A convex profile of the crown was shown to be associated with a higher distal MBL (P = .025) compared to concave and str aight profiles. [ABSTRACT FROM AUTHOR]

This retrospective study evaluated the survival rate and the clinical outcome of an endosseous implant system, as well as the marginal bone level (MBL) and the impact of the machined collar neck position on crestal bone level changes up to 2 years later. A total of 96 implants were placed in 57 patients and loaded with a final restoration after at least 3 months of healing: 15 implants were immediately placed into fresh extraction sockets, and 81 were placed in healed ridges. Marginal bone loss around implants was determined radiographically at 12 to 24 months postloading. The effects on marginal bone loss of the site (mandible vs maxilla), location (anterior vs posterior), immediate vs delayed implant, smoking habit, sex, implant length and diameter, prosthesis type (screw-retained/cemented), and the machined collar position were evaluated. The implant survival rate was 98.96% at 1 year. The mean MBL decreased significantly (0.238 mm) between baseline and loading (P < .001; post hoc test) and decreased by 0.154 mm between loading and 1 year, but this was not significant (P = .085; post hoc tests). After 2 years, the mean MBL decreased significantly (0.263 mm) between baseline and loading (P < .001) and decreased by 0.111 mm between loading and 1 year and by 0.199 mm between loading and 2 years, but these were not significant (P > .05; post hoc tests). The mean bone loss after 1 and 2 years was not significantly associated with implant type or site, smoking habit, or type of implant surgery (P = .792). However, the mean bone loss was significantly associated with the type of prosthesis and was significantly greater for cemented prostheses compared to screw-retained prostheses. A supracrestal position of the machined collar (tissue level) was associated with no bone loss, while placing the collar below the alveolar crest led to bone loss over 2 years. Of the factors evaluated, marginal bone loss after 1 and 2 years was significantly associated with prosthesis type and the machined collar position. [ABSTRACT FROM AUTHOR]