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This study aims to validate the standardized procedure for designing soft tissue substitutes (STS) adapted to optimally fit single-tooth defects in the anterior jaws and double-tooth defects in the posterior jaw and to compare mathematically modeled average shapes.Casts from 35 patients with 17 single-tooth defects in anterior region and 21 double-tooth defects in posterior region were scanned. STS were designed and sectioned in 3D slices meshes. Thickness values were documented respecting mesial-distal and buccal-lingual orientations. Graphs were embedded into images, and hierarchical clustering was applied to group STS according to shape and thickness.STS clustered into two groups per defect type. For anterior single defects, STS (n = 4) were either a small and thin oval: 7 mm buccal-lingual, 4-5 mm mesial-distal direction and 1.1-1.5 mm thick or a larger oval (n = 13): 9 mm buccal-lingual, 5-7 mm mesial-distal and 1.6 m thick. For posterior double tooth defects, STS (n = 10) were either narrow, long and thick: 6-7 mm buccal-lingual, 16-20 mm mesial-distal and 2.2 thick or a wide, thinner rectangle (n = 11): 9-11 mm buccal-lingual, 12-14 mm mesial-distal and 1.1-1.5 mm thick.The study validated the standardized digital method to design grafts for soft tissue volume augmentation and identified four average shapes for anterior single-tooth and posterior double-tooth soft tissue defects.We developed and validated a standardized digital method to design an optimal geometrical shape of a soft tissue substitute for oral volume augmentation and combined it with mathematical modeling to identify average shapes for single-interior, and double-posterior tooth defects. The identified average shapes offer the possibility to produce better-fitted xenografts or synthetic STS blocks requiring minimal chair-side adaptation leading to reduced clinical time and patient discomfort and potentially improving soft tissue volume augmentation outcomes.

Various kinds of implants of different diameters and connection types are used for patients with a range of bone densities and tooth sizes. However, comprehensive studies simultaneously analyzing the biomechanical effects of different diameters, connection types, and bone densities are scarce.The purpose of this 3-dimensional finite element analysis study was to evaluate the stress and strain distribution on implants, abutments, and surrounding bones depending on different diameters, connection types, and bone densities.Twelve 3-dimensional models of the implant, restoration, and surrounding bone were simulated in the mandibular first molar region, including 2 bone densities (low, high), 2 implant-abutment connection types (internal tissue level, internal bone level), and 3 implant diameters (3.5 mm, 4.0 mm, and 4.5 mm). The occlusal force was 200 N axially and 100 N obliquely. Statistical analysis was performed using the general linear model univariate procedure with partial eta squared (ηFor bone tissue, low-density bone induced a larger maximum and minimum principal strain (in magnitude) than high-density bone (P.001). As the implant diameter increased, the volume of the cancellous bone in low-density bone at the atrophy region (strain200 με) increased (P.001). For implant and abutment, the internal bone-level connection type was associated with increased peak stress as compared with the tissue-level connection type (P.001). For all models, the stress distribution on the implant complex was influenced by implant diameter (P.001): a decrease in implant diameter increased the stress concentration.The implant connection type had a greater impact on the stress of the implant and abutment than the diameter. A tissue-level connection was more advantageous than a bone-level connection in terms of stress distribution of the implant and abutment. Bone density was the most influential factor on bone strain. The selection of dental implants should be made considering these factors and other important factors including tooth size.

To evaluate outcome measures, methods of assessment, and analysis in clinical studies on fixed single- and multiple-unit implant restorations.Three independent electronic database searches (MEDLINE, EMBASE, and Cochrane) were done to identify prospective and retrospective clinical studies published from January 2011 up to June 2021 with ≥20 patients and minimum 1-year follow-up period on technical and clinical outcomes of implant-supported single crowns (SCs) and partial fixed dental prostheses (P-FDPs). An entire data extraction was performed to identify primarily the most reported outcome measures and later to define the choice of assessment methods of those outcome measures. The outcomes were analysed descriptively, and the strength of association was evaluated using the Pearson chi-square test (p ≤ .05).In a total 531 studies, 368 on SCs (69.3%), 70 on P-FDPs (13.1%), and 93 on both restoration types (17.5%) were included; 56.3% of all studies did not clearly define a primary outcome. The most frequent primary outcome was marginal bone level (MBL) (55.2%) followed by implant survival (5.3%), professional aesthetic evaluation (3.4%), and technical complications (2.1%). Peri-implant indices were the most reported secondary outcome (55.1%), followed by implant survival (39.9%), MBL (36%), and implant success (26.4%). Prosthetic failure (seven studies [3.9%]) was one of the least reported outcome measures.Outcome measures and their assessment methods showed high heterogeneity among studies. Primary outcomes were not often defined clearly, and the most frequently selected primary outcome was marginal bone loss. Prosthetic outcomes, implant survival, and patient-related outcomes were only infrequently reported.

To compare screw-retained and cemented all-ceramic implant-supported single crowns regarding biological and technical outcomes over a 5-year observation period.In 44 patients, 44 two-piece dental implants were placed in single-tooth gaps in the esthetic zone. Patients randomly received a screw-retained (SR) or cemented (CR) all-ceramic single crown and were then re-examined annually up to 5 years. Outcome measures included: clinical, biological, technical, and radiographic parameters. Data were statistically analyzed with Wilcoxon-Mann-Whitney, Wilcoxon, and Fisher's exact tests.During the observation period, three patients (6.8%) were loss to follow-up. Eight restorations (18.2%, CI (8.2%, 32.7%)) were lost due to technical (6 patients, 13.6% (CI (5.2%, 27.4%)), 2 CR and 4 SR group, intergroup p = .673; implants still present) or biological complications (2 patients, 4.5% (CI (0.6%, 16.5%)), only CR group, intergroup p = .201, both implants lost). This resulted in a survival rate of 81.2% (CI (65.9%, 90.1%)) on the restorative level (18 SR; 15 CR, 3 lost to follow-up). At the 5-year follow-up, the median marginal bone levels were located slightly apical relative to the implant shoulder with 0.4 mm (0.5; 0.3) (SR) and 0.4 mm (0.8; 0.3) (CR) (intergroup p = .582). Cemented restorations demonstrated a significantly higher biological complication rate (36.8%, SR: 0.0%; intergroup p = .0022), as well as a significantly higher overall complication rate (68.4%, SR: 22.7%, intergroup p = .0049). All other outcomes did not differ significantly between the two groups (p .05).All-ceramic single-tooth restorations on two-piece dental implants resulted in a relatively low survival rate. Cemented restorations were associated with a higher biological and overall complication rate than screw-retained restorations.

Purpose To evaluate the survival rates and technical outcomes of minimally invasive full-mouth rehabilitations in patients affected by dental erosion and attrition. Materials and methods For this retrospective study, 28 subjects (8 women, 20 men; mean age: 45.6 years) who suffered from generalized erosions and attrition and who were treated according to the 3-step technique were invited to participate. The patient records were reviewed, and the restorations were clinically and radiographically examined. This part of the study (part 1) evaluated restoration survival and technical outcomes using the modified United States Public Health Service criteria (mUSPHS). Survival analysis was performed using Kaplan-Meier survival statistics, and comparison between subgroups was made using log-rank test. For all other comparisons, cross-tabulations of occurrence were performed, and significance was tested using Pearson chi-square test. The level of statistical significance was set at P Results A total of 19 patients (3 women, 16 men; mean age: 45.6 years) agreed to participate. In these patients, 406 restorations (149 direct composites, 110 onlays, 147 veneers) supported by 365 teeth were examined. The mean time in service was 71.8 ± 28.6 months. Six failed restorations were identified; all were direct composites. The 6-year survival rates were 97.3% for direct composites, 98.2% for onlays, and 100% for veneers (P > .05). No differences were found among materials and locations of the restorations. Nineteen technical complications included 14 partial fractures, 3 fissures, 1 wear, and 1 decementation. The mUSPHS evaluation showed good technical outcomes. Presence or absence of a nightguard influenced restoration survival (P = .003). Conclusion Minimally invasive rehabilitations of patients with erosions/attrition with the 3-step technique are a reliable treatment option in the medium term. Protective nightguards are recommended.

Purpose To evaluate biologic and esthetic outcomes, as well as the patient-reported outcome measures (PROMs), of full-mouth rehabilitations in patients suffering from generalized erosive and/or abrasive tooth wear following the 3-step technique. Materials and methods Patients who received a minimally invasive full-mouth rehabilitation according to the 3-step technique and who were treated at the University of Geneva and/or in a private practice were considered for inclusion. The minimum service time of the restorations was 12 months. The biologic outcomes were analyzed by assessing pocket probing depth (PPD), Plaque Index (PI), and bleeding on probing (BOP). Furthermore, secondary caries, tooth vitality, and sensitivity to temperature were evaluated using the modified United States Public Health Service (USPHS) criteria. The esthetic outcomes were rated with the White Esthetic Score (WES). Finally, PROMs were evaluated using visual analog scales (VAS). Results A total of 19 patients with 406 restorations (149 direct composite resins, 110 indirect composite resin/ceramic onlays, and 147 composite resin/ceramic veneers) were examined after a mean follow-up of 71.8 ± 28.6 months. Periodontal parameters were good (mPPD = 2.9 ± 0.4; mPI = 0.1 ± 0.2; and mBOP = 0.05 ± 0.1). No secondary caries were found, and no abutment tooth had lost vitality. A total of 36 abutment teeth had moderate sensitivity, but none presented pronounced sensitivity. The rehabilitations exhibited good esthetic outcomes (mWES = 8.4 ± 1.9). Patients reported satisfying esthetic results of their rehabilitations (mean VAS = 9.2 ± 1.6) and considered their treatment as comfortable (mean VAS = 8.2 ± 2.1), while the least favorably rated parameter was the cost of treatment (mean VAS = 4.1 ± 3.2). Conclusion Minimally invasive full-mouth rehabilitations of patients with generalized tooth wear by means of the 3-step technique exhibit very good clinical medium-term results with respect to biologic and objective/subjective esthetic outcomes. The patient satisfaction with this treatment was high.

6. EAO Consensus Conference 2021, online, 11 Feb 2021 - 12 Feb 2021; Clinical oral implants research 32(S21), 336-341 (2021). doi:10.1111/clr.13797 special issue: "Special Issue: The 6th EAO Consensus Conference 2021 / edited by: Irena Sailer, Björn Klinge, Henning Schliephake", Published by Wiley-Blackwell, Oxford

Objective To assess the survival, failure, and complication rates of veneered and monolithic all-ceramic implant-supported single crowns (SCs). Methods Literature search was conducted in Medline (PubMed), Embase, and Cochrane Central Register of Controlled Trials until September 2020 for randomized, prospective, and retrospective clinical trials with follow-up time of at least 1 year, evaluating the outcome of veneered and/or monolithic all-ceramic SCs supported by titanium dental implants. Survival and complication rates were analyzed using robust Poisson's regression models. Results Forty-nine RCTs and prospective studies reporting on 57 material cohorts were included. Meta-analysis of the included studies indicated an estimated 3-year survival rate of veneered-reinforced glass-ceramic implant-supported SCs of 97.6% (95% CI: 87.0%-99.6%). The estimated 3-year survival rates were 97.0% (95% CI: 94.0%-98.5%) for monolithic-reinforced glass-ceramic implant SCs, 96.9% (95% CI: 93.4%-98.6%) for veneered densely sintered alumina SCs, 96.3% (95% CI: 93.9%-97.7%) for veneered zirconia SCs, 96.1% (95% CI: 93.4%-97.8%) for monolithic zirconia SCs and only 36.3% (95% CI: 0.04%-87.7%) for resin-matrix-ceramic (RMC) SCs. With the exception of RMC SCs (p Conclusions With the exception of RMC SCs, veneered and monolithic implant-supported ceramic SCs showed favorable short-term survival and complication rates. Significantly higher rates for ceramic chipping, however, were reported for veneered compared with monolithic ceramic SCs.

To assess the influence of bonding system and restorative material on the marginal integrity and pull-off forces of monolithic all-ceramic crowns bonded to titanium base (Ti-base) abutments.A total of 108 Ti-bases were sandblasted and divided into 9 experimental groups (n = 12 each) according to the combination of crown material (polymer-infiltrated ceramic network [PI], lithium disilicate [LD], and zirconia [ZI]) and bonding system (Multilink Hybrid Abutment [mh], PANAVIA V5 [pv], RelyX Ultimate [ru]), with their respective primers. After bonding the crowns to the Ti-base abutments, the restorations were screw-retained on implants and thermomechanically aged (1,200,000 cycles, 49 N, 1.67 Hz; 5°C to 55°C). Marginal integrity and bonding failure were evaluated under a light microscope, and pull-off forces (N) were calculated. Chi-square tests for marginal integrity, as well as one-way and two-way ANOVA for the pull-off forces, were applied (α = .05).PI presented higher marginal integrity than LD (P = .023). The bonding system pv revealed higher marginal integrity than mh (P = .005) and ru (P = .029). Differences in pull-off forces were found between restorative material and resin cement (P.001), with the highest values for ZI + ru (598 ± 192 N), PI + pv (545 ± 114 N), LD + mh (532 ± 116 N), and PI + ru (528 ± 81 N). Specimens with marginal integrity revealed higher pull-off forces than those with alteration (P = .006). Specimens presenting bonding failures (micromovements) showed lower pull-off forces than those without bonding failures (P.001).The tested CAD/CAM materials show favorable bonding performances with different bonding systems; nevertheless, a specific bonding system has to be recommended for each restorative material.

OBJECTIVES: The main objective of the study was to compare the accuracy of full-arch digital implant impressions for fixed dental prosthesis under in vitro and in vivo conditions. MATERIALS AND METHODS: Eight patients (five women and three men) with at least one edentulous arch and with 4-6 osseointegrated implants participated in this study. For each edentulous arch (n = 10), experimental screw-retained titanium bar with attached four scan bodies was fabricated. The bar containing four scan bodies was screw-retained intraorally on implants and scanned with Trios 3 intraoral scanner eight times (IOS group, in vivo). Then, the bar was attached to the master cast and scanned eight times again with the same intraoral scanner (MIOS group, in vitro). Finally, the bar with scan bodies was scanned 8 times with a laboratory scanner (reference). Precision and trueness were calculated for 3 distances and 3 angles between the scan bodies (1-2, 1-3, and 1-4) in IOS and MIOS groups. RESULTS: Precision and trueness for the largest distance (1-4) were found to be 44 ± 18 µm and 32 ± 19 µm for the IOS group and 31 ± 16 µm and 30 ± 14 µm for MIOS group, respectively. Precision and trueness for the angle between the most distant scan bodies (1-4) were 0.22 ± 0.14° and 0.18 ± 0.10° for the IOS group and 0.16 ± 0.11° and 0.07 ± 0.05° for MIOS group, respectively. CONCLUSIONS: Intraoral conditions moderately affected the precision and trueness of Trios 3 (3Shape) intraoral scanner. Results of in vitro accuracy studies cannot be directly transferred to the clinical field.

PURPOSE To evaluate the mechanical stability and complication rates of titanium (Ti) or zirconia (Zr) abutments restored with cantilevered fixed dental prostheses (cFDPs) when supported by 1 or 2 implants. MATERIALS AND METHODS A total of 32 samples were fabricated. Half of the samples received 1 implant, and the other half received 2 implants (Bone Level Implant, O 4.1, 13 mm, Straumann) to simulate the clinical situation of 2 or 3 missing maxillary incisors, respectively. Each group was divided into two subgroups (n = 8). Ti-I and Ti-II groups received Ti abutments (Anatomic Abutment, Straumann) supporting 2- or 3-unit metal cFDPs, respectively, while Zr-I and Zr-II groups received Zr abutments (IPS e.max Anatomic Abutment, Straumann). Following the cementation of cFDPs using resin cement (Multilink Automix, Ivoclar Vivadent), the samples were subjected to thermomechanical fatigue load and were subsequently loaded until fracture in a universal testing machine. Following the static loading test, stereomicroscopic analyses (Carl Zeiss) were done to identify the weakest component of the cFDP, abutment, and implant assembly. Mann-Whitney U test was used to evaluate the effect of the number of supporting implants and abutment material on fracture strength values, and the level of statistical significance was set at 5% (α = .05). RESULTS All specimens survived the aging, and no screw loosening or fracture was recorded. The mean fracture strength values were 226 N (± 26.45 ), 551.12 N (± 82.19 ), 601 N (± 41.51 ), and 664.5 N (± 37.59 ) for Zr-I, Zr-II, Ti-I, and Ti-II, respectively. The difference between fracture strength values of Ti and Zr groups was significant in favor of Ti abutments (P < .001). The number of supporting implants showed a significantly positive effect on the fracture strength of Zr abutments. CONCLUSION Zirconia abutments demonstrated lower fracture strength values than titanium abutments independent from the number of supporting implants when used under cFDPs. Two-implant supported cFDPs with zirconia abutments have the potential to withstand physiologic forces applied in the anterior region.

Monolithic zirconia implant-supported restorations connected to titanium bases or titanium inserts are increasing in popularity due to their application in a full digital workflow. These prefabricated abutments are connected to the all-ceramic superstructure by adhesive cementation. Although limited clinical data on the outcomes of this type of restoration are available, a few laboratory studies have shown possible debonding issues. This case report presents a bonding failure of a fixed dental prosthesis supported by titanium bases after short clinical use. A treatment alternative is also proposed using the available digital dental technology.

Purpose of Review The aim of this case report was to illustrate the clinical procedure integrating augmented reality (AR) for complex patient cases requiring full mouth rehabilitation. Recent Findings The introduction of AR technology to the fields of medicine and dentistry has led to numerous applications in education, surgery, and esthetics. Recently, a new AR software was introduced in esthetic dentistry which allows for real-time smile projection and thus improves communication with patients and the dental laboratory. Summary The presented case shows a patient with multiple missing teeth, diastemata, and an impaired masticatory and phonetic ability. After reconstruction of the posterior zone, the AR software was used for the conception of the esthetic zone, integrating the patient into the decision-making process. The result was an esthetic rehabilitation applying palatal and buccal veneers which corresponded to the chosen AR design. The patient appreciated the opportunity to pre-visualize a possible final outcome in an interactive way which increased his confidence in the chosen treatment. Further studies are needed to assess the precision and reproducibility of the described protocol.

Objectives: To evaluate different intervals of exposure to staining solutions and artificial aging on translucency parameter (TP 00) of CAD-CAM materials. Material and Methods: One millimeter thick square-shaped specimens (N = 288) were cut from Cerasmart (CS), IPS e.max (IE), Lava Ultimate (LU), Shofu HC (SH), Vita Enamic (VE), and Vita Suprinity (VS) and were divided into laboratory and chairside polishing. Reflection wavelength spectra, CIE D65 standard illuminant, 2 ° standard observer, SCI, UV included, SAV aperture, 6 mm diameter, were recorded at 10 nm sensitivity against white and black calibration tiles using a benchtop spectrophotometer. Subsequently, they were converted into CIEDE 2000 TP 00. After baseline measurements (T0), the specimens were divided as follows (n = 8): staining in coffee (C) and wine (W), for 60 (T1) and 120 hours (T2), and accelerated artificial aging (A). Artificial aging (ISO 4892-2 standard) was performed in two cycles of 150 KJ/m 2, for T1 and T2, respectively. TP measurements were repeated at T1 and T2. Data of TP 00 retention were submitted to analysis of variance and Fisher’s PLSD multiple comparison test (α=0.05). Results: Fisher’s PLSD critical differences among materials, time intervals and staining/aging were 0.16, 0.11 and 0.11, respectively. SH showed the highest TP 00 followed by LU > CS > IE = VS > VE. For all time intervals, the lowest TP 00 retention was observed with C. W, and A presented similar values. Conclusions: Translucency Parameter was material, time and staining/aging-dependent material. In majority of cases, it decreased upon staining/aging., Svrha rada: Procijeniti utjecaj različitih intervala izloženosti otopinama za bojenje i umjetnom starenju na parameter translucencije (TP 00) CAD/CAM materijala.Materijal i metode: Uzorci kvadratnog oblika debljine 1 mm (N = 288) izrezani su iz blokova Cerasmart (CS), IPS e.max (IE), Lava Ultimate (LU), Shofu HC (SH), Vita Enamic (VE) i Vita Suprinity ( VS) te su razvrstani u skupine u kojima je provedeno poliranje ili u laboratoriju ili u ordinaciji. Mjereni su referentnim spektrofotometrom spektri valne duljine refleksije (standardno osvjetljenje CIE D65, standardni promatrač od 2°, SCI, uključen UV, otvor SAV, promjer 6 mm) pri osjetljivosti od 10 nm na bijelim i crnim kalibracijskim pločicama i pretvoreni u CIEDE 2000 TP 00 . Nakon početnih mjerenja (T0) uzorci su podijeljeni na sljedeći način (n = 8): bojenje u kavi (C) i vinu (W) 60 (T1) i 120 sati (T2) te ubrzano umjetno starenje (A) . Umjetno starenje (ISO 4892-2 standard) obavljeno je u dvama ciklusima od 150 KJ/m2, za T1, odnosno T2. Mjerenja TP-a ponovljena su nakon T1 i T2. Podatci o TP 00 podvrgnuti su analizi varijance Fisherovim PLSD- testom višestruke usporedbe (α = 0,05).Rezultati: Kritične razlike Fisherova PLSD-testa između materijala, vremenskih intervala i bojenja/starenja bile su 0,16, 0,11, odnosno 0,11. SH je imao najviši TP 00 , a zatim slijede LU > CS > IE = VS > VE. Za sve intervale zabilježeno je najmanje zadržavanje TP 00 kod C-a. Slične vrijednosti imali su W i A. Zaključci: Parametar translucencije ovisio je o materijalu, vremenu i bojenju/starenju. U većini slučajeva smanjio se nakon bojenja/starenja.

The tasks of Working Groups 1 to 6 at the 4th Consensus Meeting of the Oral Reconstruction Foundation were to elucidate clinical recommendations for implant-supported full-arch rehabilitations in edentulous patients. Six systematic/narrative reviews were prepared to address the following subtopics: (1) the influence of medical and geriatric factors on implant survival; (2) the prevalence of peri-implant diseases; (3) the influence of material selection, attachment type, interarch space, and opposing dentition; (4) different interventions for rehabilitation of the edentulous maxilla; (5) different interventions for rehabilitation of the edentulous mandible; and (6) treatment choice and decision-making in elderly patients. Consensus statements, clinical recommendations, and implications for future research were determined based on structured group discussions and plenary session approval.

Purpose To evaluate the effect of cementation protocols on the bonding interface stability and pull-out forces of temporary implant-supported crowns bonded on a titanium base abutment (TiB) or on a temporary titanium abutment (TiA). Materials and methods A total of 60 implants were restored with PMMA-based CAD/CAM crowns. Five groups (n = 12) were created: Group 1 = TiB/SRc: crown conditioned with MMA-based liquid (SR Connect, Ivoclar Vivadent); Group 2 = TiB/50Al-MB: crown airborne particle-abraded with 50-μm Al2O3 and silanized (Monobond Plus, Ivoclar Vivadent); Group 3 = TiB/30SiOAl-SRc: crown airborne particle-abraded with 30-μm silica-coated Al2O3 (CoJet, 3M ESPE) and conditioned with MMA-based liquid (SR Connect); Group 4 = TiB/30SiOAl-MB: crown airborne particle-abraded with 30- μm silica-coated Al2O3 (CoJet) and silanized (Monobond Plus); and Group 5 = TiA/TA-PMMA: crown manually enlarged, activated, and rebased with PMMA resin (Telio Lab, Ivoclar Vivadent). Specimens in the TiB groups were cemented using a resin cement (Multilink Hybrid Abutment, Ivoclar Vivadent). After aging (120,000 cycles, 49 N, 1.67 Hz, 5°C to 55°C, 120 seconds), bonding interface failure was analyzed (50x). Pull-out forces (N) (0.5 mm/minute) and modes of failure were registered. Chi-square and Kruskal-Wallis tests were used to analyze the data (α = .05). Results Bonding failure after aging varied from 0% (Group 5) to 100% (Groups 1, 2, and 4) (P .05). Conclusion The cementation protocol had an effect on the bonding interface stability and pull-out forces of PMMA-based crowns bonded on a titanium base. Airborne particle abrasion of the crown internal surface and conditioning it with an MMA-based liquid may be recommended to improve retention of titanium base temporary restorations. Yet, for optimal outcomes, conventional temporary abutments might be preferred.

PURPOSE To test the accuracies of different methods of digital vertical dimension augmentation (VDA) by comparison with a clinical situation. MATERIALS AND METHODS Bite registrations with approximately 5 mm of VDA were made in the incisor regions of 10 subjects (mean VDA 4.5 mm). The conventional maxillary and mandibular stone casts in maximum intercuspation (MICP) and VDA bite registrations were digitized for all subjects using a laboratory scanner (control group). Lateral portraits were taken of all subjects to locate the position of the condylar axis. Four different digital VDA methods were compared to the control group: 100% rotation of the mandible referring to the lateral picture (100RL); 85% rotation and 15% translation referring to the lateral picture (85R15TL); 100% rotation in normal mounting mode of the Trios virtual articulator (100R); and jaw-motion analysis (JMA) equipment. The amount of VDA for each experimental group was compared to the control group. The augmented distances between the central incisors and the second molars were measured using 3D analyzing software. The ratio of the augmented distances between the posterior and anterior regions (P/A ratio) was calculated. One-way analysis of variance and multiple comparisons via least significant difference test were carried out to determine statistical significance. RESULTS The P/A ratio of each group was as follows: Control = 0.61; 100RL = 0.55; 85R15TL = 0.61; 100R = 0.53; JMA = 0.52. Significant differences were observed for control vs JMA and for 85R15TL vs JMA (P < .05). The addition of translational movement was the primary factor for increasing the accuracy of digital VDA, with the lateral picture being a secondary factor. CONCLUSION VDA using a virtual articulator with 100% rotation induces an error when compared to the clinical situation. When a clinician performs digital VDA, the setting of 85% rotation and 15% translation produces results closer to the real clinical condition.

Objective: The aim of this randomized multicenter clinical trial was to evaluate and compare the performance of anterior all-ceramic implant crowns based either on prefabricated zirconia abutments veneered with pressed ceramics or on CAD/CAM zirconia abutments veneered with the hand build-up technique. The null hypothesis was that there is no statistically significant difference between the two study groups. Material and methods: Forty implants were inserted in sites 14–24 (World Dental Federation [FDI]) in two centers, the Universities of Bern and Geneva, Switzerland. Twenty patients each were randomized into either Group A and restored with one-piece single crown made of a prefabricated zirconia abutment with pressed ceramic, or Group B using an individualized CAD/CAM zirconia abutment with the hand-layered technique. After 3 years, clinical, esthetic, and radiographic parameters were assessed. Results: Group A exhibited one dropout patient and one failure resulting in a survival rate of 89% after 3 years and two failures for Group B (90%). Clinical parameters presented healthy peri-implant soft tissues. Overall, no crestal bone level changes were observed (mean DIB of 0.13 mm [Group A] and 0.24 mm [Group B]). There were no significant differences at baseline, 6 months, and 1 and 3 years for DIB values between the two groups. PES and WES values evaluated at all three time points indicated stability over time for both groups and pleasing esthetic outcomes. Conclusions: Both implant-supported prosthetic pathways represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla.

The present paper presents clinical guidelines for the selection of the abutment material and level of customization for single-implant reconstructions. A systematic literature search was conducted previous to a Consensus Conference, resulting in two systematic reviews. One review focused on esthetic clinical outcomes, including esthetic indices and linear measurements, and the second focused on peri-implant soft tissue color outcomes, evaluated with spectrophotometry. The outcomes of esthetic indexes and linear measurement were highly heterogenic, hence, a meta-analysis was not feasible. All-ceramic and customized solutions showed a trend for improved results of the esthetic outcomes. Regarding soft tissue color outcomes, all-ceramic abutments induced significantly less soft tissue color changes. Both metallic and all-ceramic abutments/standard and customized components may result in clinically and esthetically acceptable reconstructions.

In recent years, numerous new dental materials have been introduced as alternatives to metal-ceramics for restorations on teeth and implants. This position paper presents the current evidence and respective clinical recommendations of the European Association for Osseointegration (EAO), one of the scientific partners of the International Journal of Prosthodontics, on material selection for single crowns (SCs) and multiple-unit implant-supported fixed dental prostheses (FDPs). Metal-ceramic restorations can be utilized in most clinical indications and are preferred to ceramic restorations in incidences such as long clinical implant crowns; cantilever implant restorations where one implant is supporting two crowns; implant-supported FDPs with extension units extending more than 7 to 8 mm (premolar size); implant-supported FDPs with more than two pontics; and implant-supported FDPs with small connector diameters due to limited intraocclusal space. Veneered or monolithic zirconia-ceramic and veneered or monolithic reinforced glass-ceramic implant-supported SCs are indicated for most SC cases in both the anterior and posterior areas. Today, implant-supported zirconia-ceramic FDPs that are conventionally veneered cannot be considered the material of first priority due to the pronounced risk for fracture of the framework and catastrophic fracture of the veneering material. Monolithic zirconia FDPs are a promising alternative to veneered implant-supported zirconia-ceramic FDPs. The mechanical stability of the translucent and shaded zirconia differs significantly between the grades of translucency. This must always be considered when clinical indications are recommended. As this specific area of prosthodontics is evolving fast, numerous studies evaluating different material options in implant prosthodontics are currently performed worldwide, and future consensus meetings will refine the present recommendations. The EAO will therefore regularly publish updated position papers on relevant topics.

Both fixed and removable implant-supported prostheses are well-established methods for replacing missing teeth in partially or fully edentulous patients. Numerous systematic reviews have been performed in recent years to evaluate the survival and complication rates of implant-retained fixed dental prostheses and implant-retained overdentures, displaying high 5-year survival rates ranging from 97.1% for fixed dental prostheses to 95%-100% for implant-retained overdentures. However, the survival rates only represent the prostheses remaining in use for a defined follow-up time, and do not account for the potential prosthetic complications that may have arisen and influence the general success of the implant treatment. The most common technical complications of fixed implant-retained single crowns are crown fracture, fractures of ceramic implant abutments, and esthetic problems. The predominant technical complication at multiple-unit, implant-retained fixed dental prostheses is fracture/chipping of the veneering ceramic. Reported technical complications for implant-retained overdentures are overdenture fracture or chipping of the veneer materials, whereas mechanical complications include implant fracture, attachment failure, and attachment housing or insert complications. To reduce the risk of such failures, a comprehensive pretreatment diagnostic work-up is essential, including defining the prosthetic goal with the aid of a wax-up or set-up and the associated ideal, prosthetically oriented three-dimensional implant position. Furthermore, selection of the ideal type of prosthesis, including the respective implant components and materials, is important for clinical long-term treatment success.

This in vitro study evaluated technical outcomes of monolithic zirconia implant-supported fixed dental prostheses (iFDPs) supported by different designs of titanium base abutments after aging and static load testing.Sixty three-unit monolithic zirconia (yttrium oxide partially stabilized tetragonal zirconia polycrystals; Y-TZP)iFDPs were produced and divided into four groups: group A-conical titanium base abutments for the prosthesis; group B-cylindrical titanium base abutments for the crown; group C-conical titanium base abutment for the prosthesis and cylindrical titanium base abutment for the crown; group D-cylindrical titanium base abutments for the prosthesis. The samples were subjected to an aging protocol and to continuous static loading until failure and analyzed visually and with specific software. The technical outcomes comprised the occurrence of debonding, screw loosening, deformation and fracture, abutment deformation and fracture, implant deformation and fracture, zirconia chipping and fracture, and bending moments. The Pearson chi-squared test (χAfter aging, a higher percentage of debonding (P = .042) and micromovement (P = .034) was recorded in group C (P = .042). The conical titanium base abutments had a higher debonding (P = .049) and a higher macromovement rate (P = .05). The static load test showed higher bending moments in group D (P = .001) and lower bending moments in group A (P = .001). Debonding was highest in group C (P = .001) and lowest in group A (P = .002). Complete loss of retention rate was highest in group C (P = .001). The conical titanium base abutment had the highest debonding rate (P = .001) and complete loss of retention (P = .001). The micromovement rate was the highest for cylindrical titanium base abutments for the crown (P = .001). The lowest screw loosening, zirconia chipping, and fracture rate (P = .001) and the highest screw deformation (P = .004) were recorded in group A. The screw deformation rate was lowest in the cylindrical titanium base abutments for the crown (P = .008).The mixed titanium base abutment design comprising one conical and one cylindrical abutment in Y-TZP iFDPs led to the highest debonding rate. The cylindrical titanium base abutment for the prosthesis provided a lower percentage of debonding and the highest load resistance.

This prospective crossover clinical trial aimed to compare the complete-digital and -analog workflows in terms of occlusal adjustment of 3-unit tooth-supported fixed dental prostheses, operator, and patient preferences.This study included twelve patients receiving fourteen 3-unit posterior FDPs. 2 FDPs were made for each restoration site: one fabricated in complete-digital workflow comprising intraoral scan with static bite registration (Trios 3) and a monolithic zirconia FDP (test); the other fabricated in complete-analog workflow comprising conventional impression/face-bow transfer and a porcelain-fused-to-metal FDP (control). The FDPs (n=28) were intraorally/provisionally fixed, and quadrant-like intraoral scans were taken for every FDP beforeafter their occlusal adjustments. Pre- and post-adjustment scans of each FDP were then superimposed using best-fit alignment (GOM Inspect) to measure the volumetric occlusal adjustment amount (mmMean occlusal adjustments were 7.63 mmWithin the limitations of this clinical study, the complete digital workflow with digital static bite-registration provided high occlusal accuracy for short-span tooth-supported FDPs. In addition, the patient and operator preferences significantly favored the digital workflow.Complete-digital workflow employing intraoral scanning and model-free fabrication of monolithic-Zr short-span tooth-supported FDPs offers an effective treatment modality with sufficient occlusal accuracy. Therefore complete-digital workflow is a valid alternative for complete-analog workflow comprising conventional impression, face-bow transfer, and use of a semi-adjustable articulator.

This scoping review aimed to present an overview of the literature on communication tools in esthetic dentistry. A variety of communication tools have been proposed to include patients in the shared decision-making (SDM) workflow. Only little is known about implementing communication tools in dentistry and their impact on patient communication and patient satisfaction. A systematic literature search was performed in Medline, Embase, Cochrane, and World of Science to identify if communication tools have an impact on patient satisfaction.The search included studies from January 1, 2000 to March 3, 2020 published in English, focusing on patient communication tools and patient satisfaction in esthetic dentistry.Out of 6678 records, 53 full-texts were examined. Ten studies were included. Data of the included studies were extracted systematically and subsequently analyzed. All studies found that patient communication utilizing specific communication tools positively impacted either patient satisfaction, patient-dentist relationship, information retention, treatment acceptance, quality of care or treatment outcome.Additional communication tools besides conventional verbal communication are able to enhance patient satisfaction, improve quality of care and establish a better patient-dentist relationship. It seems essential to further develop standardized communication tools for SDM in dental medicine, which will allow the comparison of research on this topic.This scoping review shows the importance of patient involvement in the decision-making process for improved patient satisfaction with esthetic dental treatments. With an increased implementation of communication tools, patient satisfaction and SDM may further improve in the future.

This in vitro research aimed to quantitatively evaluate the enamel and dentin tissue removal and the residual adhesion surface area (RAS) after different margin designs and locations for indirect partial restorations (IPR).A human molar was scanned using a Micro-CT and the STL file obtained was used to 3D-print 50 resin-tooth replicas. IPR standardized preparations were performed. The specimens were randomly assigned to 5 groups (n = 10), according to preparation and margin location to the dental equator (DE): 1) Rounded shoulder above the DE (SA); 2) Hollow chamfer above the DE (CA); 3) Butt joint above the DE (BJ); 4) Rounded shoulder below the DE (SB); 5) Chamfer below the DE (CB). Then, the tooth replicas were scanned and each STL file was aligned and superimposed to the original STL model file. Data of enamel and dentin volume removal and RAS were assessed and statistically analyzed (one-way ANOVA and Kruskal-Wallis tests for the two dental substrates respectively). Significance was set at p0.05.Differences in dental tissue reductions were related to the margin location. Above the equator, SA, CA, and BJ performed comparably (p0.05). Below the equator, CB was significantly more conservative in enamel reduction than SB (p0.05) and showed the highest enamel adhesive surface exposure among the tested preparations (p0.05).When the preparation margin is placed above DE, BJ determines a greater exposure of dentin, reducing the adhesive surface in enamel. Below DE, SB seems to be more aggressive in terms of tissue removal compared to CB.The results of this in vitro study suggest that in teeth requiring partial restoration with the margin below the dental equator, a chamfer preparation would be more conservative than a shoulder preparation. When above the equator, preparations with flat designs would expose more dentine providing a worse substrate for adhesion.

PURPOSE To assess the clinical outcomes of single-retainer resin-bonded fixed dental prostheses (RBFDPs) and the profilometric changes of pontic sites after a mean of 10 years in function. MATERIALS AND METHODS Ten patients (mean age 32.4 years) who had received an RBFDP replacing a single anterior tooth were recalled after 10 years. Five patients had received a subepithelial connective tissue graft (SCTG) at the pontic site. The clinical assessment comprised the following parameters: probing depth, bleeding on probing, modified plaque control record, gingival recession, measurement of the width of keratinized mucosa, and intraoral photographs and radiographs. The modified criteria of the United States Public Health Services evaluation system were applied. Additionally, patient satisfaction was recorded. Data were analyzed descriptively, and the 10-year RBFDP survival rates were calculated using Kaplan-Meier analysis. RESULTS The RBFDP survival rate after a mean follow-up of 10.0 years (range 7.4 to 13.3 years) was 100%. Neither technical failures nor biologic complications were observed. All abutment teeth remained vital, and no secondary caries were detected. Between baseline and follow-up examinations, the profilometric changes at the pontic sites were minimal, exhibiting a loss of -0.03 ± 0.10 mm (no SCTG) and 0.00 ± 0.37 mm (SCTG). CONCLUSION The present study exhibited high survival rates and low complication rates of the restorations, as well as excellent profilometric stability of the pontic sites over 10 years. The use of an RBFDP is a viable long-term treatment option for replacing a single anterior tooth.

To investigate the survival and mechanical properties of 3-unit interim fixed dental prostheses (FDPs) made with additive manufacturing (AM) technology compared to milled and conventional manual fabrication.Sixty 3-unit interim FDPs replacing the first left mandibular molar were divided in 6 groups (n = 10): manual (Man) (Protemp 4), milled (Mil) (Telio-CAD Multi), and 4 additive manufacturing (AM) groups were subdivided into 4 AM technology subgroups: direct light positioning (DLP) (Rapidshape P30 [RS]), and stereolitography (SLA) (Formlabs 2 [FL]) and the type of printed interim polymer (P Pro CB [St] and SHERAprint-cb [Sh]) (RS-St, RS-Sh, FL-St, and FL-Sh). Survival and complications were assessed after thermomechanical aging. The surviving samples were tested for fracture resistance. Kaplan-Meier test followed by log-rank test to show differences between groups was used to calculate the survival and complication rates. For fracture strength, one-way ANOVA and Tukey-b post hoc test were used to compare groups. Descriptive statistics was used for failure modes and Pearson chi-square to compare groups (α = 0.05).Survival rates among groups varied from 100% (Man, Mil and FL-Sh), 70% (FL-St), 50% (RS-Sh), and 20% (RS-Sh) (p0.001), respectively. Additional events were observed in 50% to 80% in FL-St, RS-St, and RS-Sh groups (p0.001). Man, FL-St, and RS-S showed lower mean static load resistance (p0.001). Fracture through the connector between tooth 35 and the pontic was the most prevalent type of failure.The manufacturing method, type of resin, and the printing mode had a significant influence on the mechanical properties of AM interim 3-unit FDPs.

OBJECTIVES To assess survival/success rates and patient-reported outcome of zirconia-based posterior single crowns (SCs) supported by zirconia implants in a prospective two-center study after five years of observation. MATERIAL AND METHODS Forty-five patients were restored with 45 zirconia implant-supported posterior SCs composed of zirconia frameworks hand-layered with a leucite-reinforced feldspathic ceramic. Survival rates of SCs were assessed and technical success was evaluated according to modified United States Public Health Care (USPHS) criteria. Furthermore, patient-reported outcome measures (PROMs) were assessed by applying visual analog scales (VAS). Wilcoxon matched-pairs signed-rank test, mixed-effects ordered logistic regression, and linear mixed models were used to evaluate time effects on response variables. RESULTS Forty patients were available after a mean observation period of 61.0 ± 1.4 months. One SC had to be replaced, resulting in a Kaplan-Meier (KM) survival estimate for the SCs of 97.5 ± 2.47%. Since nine reconstructions showed at least in one category a major deviation from the ideal (five major chippings, four with increased occlusal roughness, one significant crevice, and one pronounced over-contouring), the KM success estimate was 79.3 ± 5.8%. Incidence of chipping (n = 19) and occlusal roughness (n = 35) was frequent (p

STATEMENT OF PROBLEM Clinical trials are needed to evaluate the digital and conventional fabrication technology for providing fixed partial dentures (FPDs). PURPOSE The purpose of the second part of this clinical study was to compare the laboratory production time for tooth-supported, 3-unit FPDs by means of computer-aided design and computer-aided manufacturing (CAD-CAM) systems and a conventional workflow. In addition, the quality of the 3-unit framework of each treatment group was evaluated clinically. MATERIAL AND METHODS For each of 10 participants, a 3-unit FPD was fabricated. Zirconia was used as the framework material in the CAD-CAM systems and included Lava C.O.S. CAD software (3M) and centralized CAM (group L); CARES CAD software (Institut Straumann AG) and centralized CAM (group iT); and CEREC Connect CAD software (Dentsply Sirona) and centralized CAM (group C). The noble metal framework in the conventional workflow (group K) was fabricated by means of the traditional lost-wax technique. All frameworks were evaluated clinically before veneering. The time for the fabrication of the cast, the 3-unit framework, and the veneering process was recorded. In addition, chairside time during the clinical appointment for the evaluation of the framework was recorded. The paired Wilcoxon test together with appropriate Bonferroni correction was applied to detect differences among treatment groups (α=.05). RESULTS The total effective working time (mean ±standard deviation) for the dental technician was 220 ±29 minutes in group L, 217 ±23 minutes in group iT, 262 ±22 minutes in group C, and 370 ±34 minutes in group K. The dental technician spent significantly more time in the conventional workflow than in the digital workflow, independent of the CAD-CAM systems used (P

The objective of this trial study was to assess whether submucosal veneering of internally connected zirconia abutments influences clinical, radiographic, and technical outcomes of single-tooth implant-borne reconstructions at 5 years after loading. A total of 20 patients with 20 single-tooth implants in the anterior or premolar area of the maxilla or mandible were included. The implants were randomly restored with fixed single-tooth reconstructions using either pink-veneered customized zirconia abutments (test group = 10) or nonveneered customized zirconia abutments (control group = 10). All reconstructions were adhesively cemented with all-ceramic crowns. Follow-up examinations were performed at baseline (7 to 10 days after crown insertion) and at 1, 3, and 5 years after loading, at which points the following were assessed: periodontal parameters such as probing depth (PD), bleeding on probing (BOP), and marginal bone levels, as well as technical outcomes using the modified United States Public Health Service (USPHS) criteria. Statistical comparisons were based on the Wilcoxon-Mann-Whitney test. Sixteen patients attended the 5-year follow-up. At 5 years, the implant survival rate was 100% and the prosthetic survival rate was 94.1% (one abutment fracture in the test group). Veneering of the submucosal part of zirconia abutments resulted in significantly higher mean PD values: 3.6 ± 0.4 mm (test group) and 3.0 ± 0.5 mm (control group), P = .042. Marginal bone levels at 5 years and changes up to 5 years were not significantly different between groups (P > .05). One crown exhibited an abutment fracture and two crowns a minor chipping (17.6% overall technical complication rate). Limited by a small sample size, veneering of the submucosal part of internally connected zirconia abutments led to outcomes that were less favorable biologically (PD, BOP, and KM), but similar to nonveneered abutments radiographically and technically.

STATEMENT OF PROBLEM Clinical trials are needed to evaluate digital and conventional technologies for providing fixed partial dentures. PURPOSE The purpose of the first part of this clinical study was to test whether complete-arch digital scans were similar to or better than complete-arch conventional impressions regarding time efficiency and participant and clinician perceptions. MATERIAL AND METHODS Ten participants in need of a posterior tooth-supported 3-unit fixed partial denture were included. Three intraoral digital scanners and subsequent workflows (Lava C.O.S.; 3M [Lava], iTero; Align Technology Inc [iTero], Cerec Bluecam; Dentsply Sirona [Cerec]) were compared with the conventional impression method using polyether (Permadyne; 3M) and the conventional workflow. A computer-generated randomization list was used to determine the sequence of the tested impression procedures for each participant. The time needed for the impression procedures, including the occlusal registration, was assessed. In addition, the participant and clinician perceptions of the comfort and difficulty of the impression were rated by means of visual analog scales. Data were analyzed with the nonparametric paired Wilcoxon test together with an appropriate Bonferroni correction to detect differences among the impression systems (α=.05). RESULTS The total time for the complete-arch impressions, including the preparation (powdering) and the occlusal registration, was shorter for the conventional impression than for the digital scans (Lava 1091 ±523 seconds, iTero 1313 ±418 seconds, Cerec 1702 ±558 seconds, conventional 658 ±181 seconds). The difference was statistically significant for 2 of the 3 digital scanners (iTero P=.001, Cerec P

Objectives The aim of this retrospective clinical study was to investigate the survival rate, technical and biologic complications of leucite-reinforced glass-ceramic crowns after a follow-up time of 13–15 years. Material and methods Fifty-three patients with 131 crowns were invited to the follow-up visit. The reconstructions were re-examined clinically and radiographically using the modified USPHS criteria and periodontal parameters of probing pocket depth (PPD), plaque index (PI), sulcus bleeding index (SBI). Patient satisfaction and post-operative sensitivity of the abutment teeth were evaluated with a questionnaire. The overall survival rate and the Kaplan-Meier survival estimate were calculated both on crown and patient level. Technical and biological complications were reported descriptively on crown level. The p-value Results Thirty-eight patients (12 men, 26 women) with 93 crowns were examined. The overall survival rate of all the crowns was 79.6% after a mean observation period of 14.4 ± 1.2 years. Most of the failures occurred after 11.1 years. The most common clinical failures were inacceptable ceramic fractures or chippings, which occurred in 5 out of 93 crowns (5.4%) and periodontitis, seen in 4 out of 93 teeth (4.3%). The most frequent technical complications were related to occlusal wear. Biological complications were not common. Conclusions Leucite-reinforced glass-ceramic crowns showed a high survival rate of 79.6% after an observation period of 13–15 years. Ceramic fractures and periodontitis accounted for the majority of clinical failures. Clinical significance Leucite-reinforced glass-ceramic crowns can be considered a safe and predictable treatment choice for restoring both anterior and posterior teeth.

The aim of this study was to investigate the effects of saliva contamination and the cleaning of the bond surface of titanium base (ti-base) abutments on the bonding stability and retention force values. The bond surface of the ti-base abutments was treated with airborne-particle abrasion. After contamination, the ti-base abutments underwent different cleaning protocols: water spray (H2O), alcohol (ALC), suspension of zirconium particles (SZP), reapplied airborne-particle abrasion (APA), and a control condition without contamination and cleaning (CTR). All lithium disilicate crowns were bonded to the ti-base abutments using a primer and a self-curing composite. Bonded specimens underwent thermo-mechanical aging. Bond failure analysis and pull-off testing were performed. Bond failure occurred more frequently in groups H2O, ALC, SZP, and APA (p &lt, 0.05). Significant differences in retention force values were only found between CTR and ALC (p &lt, 0.05). Specimens which did not show bond failure after ageing had higher retention force values than the specimens that showed bond failure (p &lt, 0.05). Saliva contamination with cleaning can degrade the bonding properties to titanium. For the retention force values, only the protocol with alcohol after contamination could not restore the values.

OBJECTIVE To investigate the impact of timing of implant placement and loading on implant survival and biological outcomes of multiple-unit implant-supported fixed dental prosthesis (FDPs). MATERIAL AND METHODS A literature search was performed by three independent reviewers for studies reporting on ≥10 patients with FPDs supported by ≥two implants over ≥3 years of follow-up. Data were analyzed on implant survival and biological complications as primary outcomes and biological events, including changes in peri-implant marginal bone level (MBL), probing depth, soft-tissue level, and health condition as secondary outcomes. RESULTS 7002 titles were identified, 360 full-texts were screened, and 14 studies were included. These comprised 6 randomized controlled studies (RCTs), 5 cohort studies, and 3 case series with identifiable implant placement and loading protocols in five of 09 possible combinations. All groups but one (IPIL) showed implant survival rates >90%. A meta-analysis based on 3 RCTs found no differences in survival rate between DPIL and DPDL (p = .227). CONCLUSIONS High survival rates for all studied implant placement and loading combinations were shown for FPDs over ≥3 years of follow-up. When a delayed implant placement protocol is applied, immediate or delayed loading demonstrated similar survival rates. The heterogeneity of the data did not allow to draw any further conclusions on the occurrence of biological complications related to timing of implant placement/loading.

Purpose To systematically review the influence of abutment material and configuration on the soft tissue esthetic outcomes of implant-supported single crowns (iSCs) after 3 years. Materials and methods An electronic search on MEDLINE (PubMed) from January 2000 to July 2019 was conducted for clinical trials with no language restrictions. The focus question was: In partially edentulous patients with iSCs, does the abutment material (metal vs ceramic) or the configuration (standardized vs customized) have an effect on the soft tissue esthetic outcomes? Randomized controlled trials, controlled clinical trials, and prospective or retrospective case series with at least 10 patients and a minimum of 3 years of follow-up were included. The esthetic outcomes Pink Esthetic Score (PES), PES/White Esthetic Score (WES; ie, modPES), Papilla Index (PI), soft tissue recession, and papilla height change were extracted. Meta-analysis was performed when applicable. Results Of the 6,399 titles identified, 27 studies were included. Combined mean PES/modPES scores, translated into a scale of 0 to 100, were 68.8 for ceramic, 74.2 for metal (P = .392), 71.9 for customized, and 71.3 for standard (P = .981) abutments. Mean soft tissue recession was also similar between the abutment groups, abutment material (P = .850), and configuration (P = .849), ranging from -1.09 mm to +0.59 mm gain. Papilla height changes ranged from -1.22 mm to +1.0 mm gain. The reported mean PI was 2.16 for customized, 2.06 for standard (P = .552), 2.01 for ceramic, and 2.28 for metallic (P = .04) abutments. Conclusion This systematic review showed that the abutment material and configuration had minimal impact on the evaluated soft tissue esthetic outcomes. Future research focusing on the included parameters in a randomized controlled manner is needed to validate the present findings.

Deproteinized bovine bone mineral particles embedded in collagen (DBBM-C) are widely used for bone regenerations with excellent, albeit sometimes variable clinical outcomes. Clinicians usually prepare DBBM-C by mixing with blood. Replacing blood by saline represents an alternative. We investigated if saline treatment could improve DBBM-C i. handling in vitro and ii. biological performances in a rabbit calvarial model. In vitro, DBBM-C blocks soaked in saline or blood were submitted to compression tests. In vivo, four poly ether ether ketone (PEEK)cylinders were placed on 16 rabbit skulls, filled with DBBM-C soaked in blood or saline for 2–4–8–12 weeks before histomorphometry. DBBM-C blocks were fully hydrated after 30 s in saline when 120 s in blood could not hydrate blocks core. Stiffness gradually decreased 2.5-fold after blood soaking whereas a six-fold decrease was measured after 30 s in saline. In vivo, saline treatment allowed 50% more bone regeneration during the first month when compared to blood soaking. This difference was then no longer visible. New bone morphology and maturity were equivalent in both conditions. DBBM-C saline-soaking facilitated its handling and accelerated bone regeneration of highly qualitative tissues when compared to blood treatment. Saline pretreatment thus may increase the clinical predictability of bone augmentation procedures.

To digitally evaluate the volumetric wear of four different implant-crown materials and their antagonists after artificial aging using an intraoral scanner (IOS) device and a laboratory desktop scanner.A total of 48 implants were restored with monolithic crowns divided according to restorative material: lithium disilicate (LDS), zirconia (ZR), polymerinfiltrated ceramic network (PICN), and porcelain fused to metal (PFM). Each specimen was scanned using a desktop scanner (LAB; iScan D104, IMETRIC 3D) and an IOS (TRIOS 3, 3Shape) before and after chewing simulation (1,200,000 cycles, 49 N, steatite antagonist, 5°C to 50°C). The obtained STL files were superimposed, and the volumetric loss of substance of the crowns and their antagonists was quantified (Materialise 3-matic). Kruskal-Wallis, Spearman rho, and paired t tests were used to analyze the data (α = .05).The means of volume loss for each restorative material varied between 0.05 ± 0.06 mmPolished ZR was the most wear-resistant material and the least abrasive to the respective antagonist among the tested ceramics. For the quantification of wear, this IOS device can be used as an alternative to desktop scanners.

OBJECTIVES To evaluate mechanical stability (survival and complication rates) and bending moments of different all-ceramic monolithic restorations bonded to titanium bases (hybrid abutment-crowns) or to customized titanium abutments compared to porcelain-fused-to-metal crowns (PFM) after thermo-mechanical aging. MATERIAL AND METHODS Sixty conical connection implants (4.3 mm-diameter) were divided in five groups (n = 12): PFM using gold abutment (GAbut-PFM), lithium disilicate crown bonded to customized titanium abutment (TAbut+LDS), lithium disilicate abutment-crown bonded to titanium base (TiBase+LDS), zirconia abutment-crown bonded to titanium base (TiBase+ZR), polymer-infiltrated ceramic-network (PICN) abutment-crown bonded to titanium base (TiBase+PICN). Simultaneous thermocycling (5°-55°C) and chewing simulation (1,200,000-cycles, 49 N, 1.67 Hz) were applied. Catastrophic and non-catastrophic events were evaluated under light microscope, and survival and complication rates were calculated. Specimens that survived aging were loaded until failure and bending moments were calculated. RESULTS Survival rates after aging were 100% (TAbut+LDS, TiBase+LDS), 91.7% (GA-PFM), 66.7% (TiBase+ZR) and 58.3% (TiBase+PICN) and differed among the groups (p = .006). Non-catastrophic events as screw loosening (GA-PFM) and loss of retention or micro-/macro-movement (TiBase groups) were observed. Complication rates varied among the groups (p

Purpose To evaluate the accuracy of superimposition of customized abutment library data onto scanned abutment data according to the extent of the scanning area. Materials and methods A patient model was fabricated by a 3D printer (Probo, DIO Implant), and a customized abutment was fabricated using a four-axis milling machine (ARUM 4X-100, Doowon). The customized abutment library data were generated using a laboratory scanner (E3, 3Shape) for superimposition after intraoral scanning. A cone-shaped structure was embedded into the library data at the center of the connection part. The customized abutment was placed on the model, and the model was scanned using a laboratory scanner to produce reference data. Three different test group datasets were generated using intraoral scanner and computer-aided design software: (1) fully scanned customized abutment; (2) insufficiently scanned proximal surface; and (3) insufficiently scanned margin, assuming challenging intraoral conditions. The library data were superimposed onto each test group; thereafter, the distance and angle between the reference and test group data were analyzed by using the embedded cone. Statistical analysis was performed using one-way analysis of variance followed by post hoc Tukey test for multiple comparisons. Results There were no statistically significant differences between the mean distance and angle of the test group data (with three different scanning areas) and the reference data. Conclusion The superimposition technique can be used clinically, not only when the scan is complete, but also when the proximal surface and margin of the customized abutment have been scanned incompletely.

Die DVT generiert dreidimensionale Daten in digitaler Form. Dies ermoglicht, die gewonnenen komplexen Informationen einerseits automatisiert auszuwerten und andererseits konsequent und vollstandig digital weiter zu verwenden. Beide Aspekte werden im vorliegenden Kapitel behandelt. Die automatisierte Bilddatenauswertung steckt fur die DVT noch in den Anfangen. Wir erwarten fur die Zukunft einen schrittweisen Einzug in die Praxis. In medizinischen Bereichen ist dies schon erkennbar: Bei der „Kapselendoskopie“ mittels „Kamerapille“ werden mehrere Tausend Fotos aus dem Magen-Darm-Trakt erzeugt. Diese werden vor der Befundung automatisiert vorsortiert. Der volldigitale Workflow unter Einbezug der DVT hingegen ist z. B. in der Implantologie schon in der klinischen Anwendung etabliert. Ein vollstandiger In-House-Workflow, wie im Bereich der Inlay- und Kronenherstellung oft schon etabliert, ist bei dieser Anwendung aber noch die Ausnahme.

PURPOSE To investigate the differences in accuracy (trueness and precision) of five different optical impression systems. MATERIALS AND METHODS The accuracy of the following optical impression systems was tested: (1) CEREC Bluecam (BL; Dentsply Sirona), (2) CEREC Omnicam (OM, Dentsply Sirona); (3) PlanScan (PL; Planmeca); (4) True Definition Scanner (TD; 3M ESPE); and (5) Trios 3 (TR; 3Shape). A standard plastic study model represented a patient with a fully dentate maxilla (ANA-4 V CER, frasaco). Three clinical situations were simulated: Patient 1 (P1): fully dentate; Patient 2 (P2): anterior partial edentulism (two missing incisors); and Patient 3 (P3): posterior partial edentulism (P3) (missing premolar and molar). The models were scanned with a reference scanner (IScan D104i, Imetric), and the digitalized models were used as reference for all comparisons. Then, optical impressions were made for the three clinical scenarios (n = 10 per group). RESULTS In situation P1, the TD group provided the highest trueness (180.2 ± 46.3μm). In situation P2, the highest trueness was found in the TD (97.9 ± 27.6 μm) and TR (105 ± 9.5μm) groups, and in situation P3, TR had the highest trueness (P < .05) with a median RMS value of 76.2 ± 5.6 μm. In terms of precision, TR provided the highest precision (P < .05) in all three clinical situations, with RMS values 76.7 ± 26 μm for P1, 46.8 ± 14.1 μm for P2, and 39.7 ± 9.1 μm for P3. CONCLUSION Two optical impression systems (TR and TD) were superior to the other tested systems in most of the measurements. However, none of the tested systems was clearly superior with respect to both trueness and precision.

Purpose: To evaluate survival, complication rates, and bending moments of one- and two-piece zirconia implants restored with different abutment materials and lithium disilicate crowns after aging, compared to titanium implants restored with titanium base-supported lithium disilicate crowns. Materials and methods: Sixty anterior crowns were either screwretained on two-piece titanium implants (C) and two-piece zirconia implants (T1, T2, T3) or cemented on one-piece zirconia implants (T4), resulting in 5 groups with 12 specimens each. For the screw-retained crowns, different abutment materials and implant connections were tested: titanium base with internal conical connection and horizontal joint component (C and T2), zirconia with internal hexagonal connection and horizontal joint component (T1), and polyetherketoneketone with internal hexagonal connection and horizontal joint component (T3). After artificial aging with thermocycling (5°C to 50°C) and chewing simulation (1,200,000 cycles, 49 N, 1.67 Hz), the surviving specimens were loaded until fracture, and the bending moments were calculated. Survival rates and respective differences during aging were analyzed with the Kaplan-Meier log-rank test, while complication rates were compared with chi-square tests. Bending moment data were evaluated using the Kruskal-Wallis test (α = .05). Results: Survival rates after artificial aging ranged from 75% (T1) to 100% (C and T4) without significant differences between the groups (P > .05). Only 41.5% of the surviving specimens were free of complications, while the remaining presented screw-loosening, loss of retention of crowns, or cracks on the crown or implant level. The complication rates varied significantly among the groups (P < .05). The mean bending moments were 173.7 × 20.1 (C), 114.5 × 20.1 (T1), 171.1 × 46.1 (T2), 258.1 × 147.4 (T3), and 194.7 × 30.9 Ncm (T4), and group T1 exhibited significantly lower median bending moment values than the other groups (P < .001). Conclusion: The zirconia one- and two-piece implants presented high survival rates after aging, yet the number of technical complications was high. New prosthetic solutions, such as titanium bases or polyetherketoneketone abutments, may offer a comparable treatment option to restore two-piece zirconia implants.

Statement of problem Published data have shown that a mechanical surface treatment of titanium surfaces increases bonding potential. However, most of the studies are based on shear or tensile tests performed on flat-surfaced specimens and do not take into consideration the retention given by the titanium base (ti-base) axial walls and the thermomechanical loading seen in a clinical setting. Purpose The purpose of this in vitro study was to evaluate the influence of different airborne-particle abrasion (APA) methods of the ti-base surface on the stability of the bonded interface and retention forces between these titanium bases and lithium disilicate crowns after thermomechanical aging. Material and methods Sixty internal connection implants (Conelog) were restored with lithium disilicate crowns and bonded to the corresponding ti-bases (Conelog). The ti-bases were divided into 4 groups (n=15), 3 experimental groups applying different APA methods, 30-μm silica-modified Al2O3 particles (CoJet) (30-SiO-AlO), 50-μm Al2O3 (Cobra Aluoxyd) (50-AlO), 110-μm silica-modified Al2O3 particles (Rocatec Plus) (110-SiO-AlO), and 1 control group (NoT). Ti-bases were airborne-particle abraded (10 seconds, 0.25 MPa at a 10-mm distance) under standardized conditions in a custom-made APA device. All crowns were cemented with a resin cement (Multilink Hybrid Abutment). After aging (1 200 000 cycles, 49 N, 1.67 Hz; 5 °C-55 °C, 120 seconds), all specimens were assessed for the presence of bond failures by optical microscopy (×50). The retention forces (N) were tested by using a pull-off test (0.5mm/min). Modes of failure were classified (Type 1, 2, or 3). An additional ti-base representing each group was prepared for surface roughness (μm) calculation (Ra, Rc, Rz) with a noncontact laser profilometer, and representative scanning electron microscope (SEM) images were recorded (×1000). Chi-squared tests were performed to analyze the bonded interface failure and modes of failure, and a Kruskal-Wallis test was selected to evaluate retention force values (α=.05). Results The percentages of bonding failure after aging were 73.3% (NoT), 40% (30-SiO-AlO), 6.7% (50-AlO), and 40% (110-SiO-AlO). The stability of the bonded interface was influenced by the APA method applied (P Conclusions Airborne-particle abrasion of the titanium surface increased the bond stability and retention forces between the ti-base and the respective crown. The use of 50-μm Al2O3 provided the most stable bonded interface among the different treatments.

Purpose To analyze the influence of material selection, attachment type, interarch space, and opposing dentition on the prosthetic outcomes of fixed and removable implant complete prostheses (FCIPs and RCIPs, respectively). Materials and methods This review was designed as an overview of systematic reviews. An electronic database search was performed to identify scientific literature that reported on FCIPs and RCIPs. The last search was performed in January 2020. The final inclusion of systematic reviews for data extraction was decided by consensus of the authors. The included studies were analyzed qualitatively. Results A total of 21 systematic reviews (FCIP: n = 11, RCIP: n = 10) out of 5,733 articles initially identified were included for data extraction and interpretation. High overall 5-year and 10-year prosthesis survival rates were shown for FCIPs and RCIPs (93.3% to 100% and 96.9% to 100%, respectively). Chipping/fracture of the veneering material was the most frequent technical complication for FCIPs, and attachment-related complications were the main technical problems for RCIPs. For FCIPs, the effect of prosthetic material was not significant on the technical complications nor the survival rates. No studies were identified that provided direct information on the effect of interarch space in FCIPs and RCIPs. Conclusions Both FCIPs and RCIPs obtained high overall survival rates, but technical complications cannot be avoided with either prosthesis type. No prosthetic material can be considered as the material of choice over another. Attachment type has no influence on the overall clinical outcomes of RCIPs. The influence of opposing dentition and the required prosthetic space were not investigated sufficiently.