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Objective: To analyze the influence of restoration design (partial‐coverage restoration vs. crown) and ceramic layer thickness on the performance and failure loads of CAD/CAM‐fabricated lithium disilicate (LDS) reconstructions on molars after fatigue. Materials and Methods: Seventy‐two posterior monolithic CAD/CAM‐fabricated LDS restorations (IPS e.max CAD, Ivoclar Vivadent) with different occlusal/buccal ceramic layer thicknesses (1.5/0.8, 1.0/0.6, and 0.5/0.4 mm) and restoration designs (PCR: non‐retentive full‐veneer/partial‐coverage restoration, C: crown,) were investigated and divided into six groups (n = 12, test: PCR‐1.5, PCR‐1.0, PCR‐0.5; control: C‐1.5, C‐1.0, C‐0.5). LDS restorations were adhesively bonded (Variolink Esthetic DC, Ivoclar Vivadent) to dentin‐analogue composite dies (Z100, 3M ESPE). All specimens were subjected to thermomechanical loading (1.2 million cycles, 49 N, 1.6 Hz, 5–55°C) and exposed to single load to failure testing. Failure analysis was performed with light and scanning electron microscopies. Data were statistically analyzed using ANOVA, Tukey‐Test, and t‐test (p < 0.05). Results: Eight crown samples (C‐0.5) and one PCR specimen (PCR‐0.5) revealed cracks after fatigue, resulting in an overall success rate of 87.5% (crowns: 75%, PCRs: 96.88%). Direct comparisons of PCRs versus crowns for thicknesses of 0.5 mm (p < 0.001) and 1.0 mm (p = 0.004) were significant and in favor of PCRs. Minimally invasive PCRs (0.5 and 1.0 mm) outperformed crowns with the identical ceramic thickness. No difference was detected (p = 0.276) between thickness 1.5 mm PCRs and crowns. Conclusions: Minimally invasive monolithic CAD/CAM‐fabricated posterior LDS PCRs (0.5 and 1.0 mm) resulted in superior failure load values compared to minimally invasive crowns. Minimally invasive crowns (0.5 mm) are prone to cracks after fatigue. Clinical Significance: Minimally invasive CAD/CAM‐fabricated LDS PCR restorations with a non‐retentive preparation design should be considered over single crowns for molar rehabilitation. [ABSTRACT FROM AUTHOR]

Objective: To analyze the influence of titanium‐base (straight [SSC]/angulated‐screw‐channel [ASC]) on failure‐loads and bending‐moments of two‐piece ceramic and titanium–zirconium implants restored with monolithic‐zirconia crowns after fatigue. Materials and Methods: Thirty‐two anterior monolithic‐screw‐retained zirconia crowns were divided into four groups (n = 8/group) according to the factors: (1) type of implant material: two‐piece titanium–zirconium implant (Ti–Zr; control‐group) versus two‐piece ceramic implant (CI; test‐group) and (2) type of titanium‐base: SSC (0° angle) versus ASC (25°). An intact implant was used for field emission gun‐scanning electronic microscopy (FEG‐SEM) characterization and Raman spectroscopy for phase analyses and residual stress quantification. All samples were exposed to fatigue with thermodynamic loading (1.2‐million‐cycles, 49 N, 1.6 Hz, 5–55°C) at a 30° angle. Surviving specimens were loaded until failure (SLF) and bending moments were recorded. Failed samples were examined using light microscope and SEM. Statistical analyses included ANOVA and Mann–Whitney U‐test. Results: Raman‐spectroscopy revealed the presence of residual compressive stresses. FEG‐SEM revealed a roughened surface between threads and polished surface at the cervical‐collar of the ceramic implant. All samples survived fatigue and were free of complications. Mean bending‐moments (±SD) were: Ti‐Zr‐0: 241 ± 45 N cm, Ti‐Zr‐25: 303 ± 86 N cm, CI‐0: 326 ± 58 N cm, CI‐25: 434 ± 71 N cm. Titanium‐base and implant‐material had significant effects in favor of ASC titanium bases (p =.001) and ceramic‐implants (p <.001). Failure analysis after SLF revealed severe fractures in ceramic implants, whereas titanium implants were restricted to plastic deformation. Conclusions: Ceramic and titanium implants exhibited high reliability after fatigue, with no failures. From a mechanical perspective, titanium bases with ASC can be recommended for both ceramic and titanium implants and are safe for clinical application. [ABSTRACT FROM AUTHOR]

Objectives: Group‐2 reviewed the scientific evidence in the field of «Technology». Focused research questions were: (1) additive versus subtractive manufacturing of implant restorations; (2) survival, complications, and esthetics comparing prefabricated versus customized abutments; and (3) survival of posterior implant‐supported multi‐unit fixed dental prostheses. Materials and Methods: Literature was systematically screened, and 67 publications could be critically reviewed following PRISMA guidelines, resulting in three systematic reviews. Consensus statements were presented to the plenary where after modification, those were accepted. Results: Additively fabricated implant restorations of zirconia and polymers were investigated for marginal/internal adaptation and mechanical properties without clear results in favor of one technology or material. Titanium base abutments for screw‐retained implant single crowns compared to customized abutments did not show significant differences concerning 1‐year survival. PFM, veneered and monolithic zirconia implant‐supported multi‐unit posterior fixed dental prostheses demonstrated similar high 3‐year survival rates, whereas veneered restorations exhibited the highest annual ceramic fracture and chipping rates. Conclusions: For interim tooth‐colored implant single crowns both additive and subtractive manufacturing are viable techniques. The clinical performance of additively produced restorations remains to be investigated. Implant single crowns on titanium base abutments show similar clinical performance compared to other type of abutments; however, long‐term clinical data from RCTs are needed. The abutment selection should be considered already during the planning phase. Digital planning facilitates 3D visualization of the prosthetic design including abutment selection. In the posterior area, monolithic zirconia is recommended as the material of choice for multi‐unit implant restorations to reduce technical complications. [ABSTRACT FROM AUTHOR]

Purpose: This laboratory study analyzed the influence of retention mode (screw‐ vs cement retained) and fatigue application on the failure load of monolithic lithium‐disilicate (LDS) implant‐supported single crowns (ISSC). Material and Methods: A total of 72 samples of monolithic LDS (*Ivoclar Vivadent) ISSC were divided into three groups (n = 24) according to their type of retention mode: Group Ti‐CAD: Titanium base (SICvantage CAD/CAM Abutment red (SIC invent AG), screw‐retained milled monolithic LDS (IPS e.max CAD*); Group Ti‐P: Titanium base (SICvantage CAD/CAM Abutment red), screw‐retained pressed monolithic LDS (IPS e.max Press*) and Group Ti‐Cust: Titanium base with cemented press LDS (IPS e.max Press*) crown on a LDS (IPS e.max Press*) custom abutment. A mandibular first molar implant‐supported single crown model was investigated (Titanium implant: SICvantage‐max, SIC invent AG, diameter: 4.2 mm, length: 11.5 mm). Half of each group (n = 12) w​ere exposed to fatigue with cyclic mechanical loading (F = 198 N, 1.2 million cycles) and simultaneous thermocycling (5‐55°C). Single load to failure testing was performed, before (Subgroups Ti‐CAD, Ti‐P, and Ti‐Cust) and after (Subgroups Ti‐CAD‐F, Ti‐P‐F, and Ti‐Cust‐F) fatigue. Weibull distribution was used to determine the characteristic strength and Weibull modulus differences between groups. Probability of survival at 900N load was calculated. Results: No samples failed during fatigue. Characteristic strength values were as follow: Ti‐CAD: 3259.5N, Ti‐CAD‐F: 2926N, Ti‐P: 2763N, Ti‐P‐F: 2841N, Ti‐Cust: 2789N, Ti‐Cust‐F: 2194N. Whereas no difference was observed between pressed or milled monolithic crowns cemented to Ti‐base, regardless of loading condition, fatigue decreased the characteristic strength of crowns cemented to custom abutments. Probability of survival at 900 N was not significantly different between groups. Conclusions: Screw‐retained pressed or milled monolithic LDS ISSC, cemented directly to Ti‐base abutments or LDS crowns cemented to custom ceramic abutments resist physiological chewing forces after simulated 5‐year aging in the artificial mouth and presented equally high probability of survival. However, a significant decrease in load to failure was observed in LDS crowns cemented to custom ceramic abutments after fatigue. Prospective clinical trials are needed to confirm the results of this laboratory investigation. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Overview Conclusion Clinical Significance To provide a guide for conducting systematic reviews and meta‐analyses in dentistry, with emphasis on translating research findings into clinical practice.Systematic reviews are essential tools for synthesizing research findings and translating evidence into clinical practice. These reviews help to identify the most effective treatment options and to determine areas requiring further research. A structured approach, including defining a concise research question, conducting comprehensive literature searches, and assessing the risk of bias, is critical for ensuring the review's trustworthiness. The GRADE approach facilitates the assessment of the certainty of evidence, which is crucial for formulating conclusions and making informed clinical decisions.Systematic reviews provide invaluable insights into clinical decision‐making by compiling, analyzing, and synthesizing multiple primary studies. Following a rigorous methodology ensures that systematic reviews are comprehensive, unbiased, and clinically relevant, ultimately contributing to better patient care and achieving better clinical outcomes.Methodologically sound systematic reviews and meta‐analyses provide clinicians with high‐quality, synthesized evidence, enabling informed clinical decisions and improved patient outcomes. They save time by consolidating research, informing treatment choices, and facilitating the translation of knowledge into clinical practice. [ABSTRACT FROM AUTHOR]

Advances in computer-aided design (CAD) / computer-aided manufacturing (CAM) technologies and their ease of application enabled the development of novel treatment concepts for modern prosthodontics. This recent paradigm shift in fixed prosthodontics from traditional to minimally invasive treatment approaches is evidenced by the clinical long-term success of bonded CAD/CAM glass-ceramic restorations. Today, defect-oriented restorations, such as inlays, onlays, and posterior crowns, are predominately fabricated from glass-ceramics in monolithic application. The variety of CAD/CAM ceramic restorative systems is constantly evolving to meet the increased demands for highly aesthetic, biocompatible, and long-lasting restorations. Recently introduced polymer-infiltrated ceramic network CAD/CAM blocks add innovative treatment options in CAD/CAM chairside 1-visit restorations. The material-specific high-edge stability enables the CAD/CAM machinability of thin restoration margins. Full-contour zirconia restorations are constantly gaining market share at the expense of bilayered systems. Advancements in material science and bonding protocols foster the development of novel material combinations or fabrication techniques of proven high-strength zirconia ceramics. CAD/CAM applications offer a standardized manufacturing process resulting in a reliable, predictable, and economic workflow for individual and complex teeth-supported restorations. More evidence from long-term clinical studies is needed to verify the clinical performance of monolithic polymer-infiltrated ceramic network and zirconia teeth-supported minimally invasive and extensive restorations. [ABSTRACT FROM AUTHOR]

The bonding of implant-supported prostheses is determined by abutment material, convergence angle, height, surface treatment, and luting agents. However, studies evaluating the bonding of luting agents to titanium base abutments with different heights under fatigue conditions are scarce. The purpose of this in vitro study was to evaluate the retention of zirconia crowns bonded with different luting agents to titanium base abutments of different heights before and after fatigue testing. Zirconia crowns were designed, milled, and distributed into 4 experimental groups according to the luting agents (G-Multi Primer/G-Cem LinkForce [MP/GC] and Scotchbond Universal/RelyX Ultimate [SU/RU]) and titanium base abutment heights (2.5 mm and 4 mm) (n=10). Pull-out testing was performed in a universal testing machine at a crosshead speed of 1 mm/min until crown displacement. Fatigue testing was performed by an electric precision fatigue simulator (1×106 cycles; 100 N; and 15 Hz), followed by pull-out testing of fatigued specimens. Collected data were statistically evaluated by using a linear mixed model after post hoc comparisons by the least significant difference test (α=.05). Luting agents, abutment heights, and fatigue influenced the bonding retention of zirconia crowns to titanium base abutments. SU/RU agents promoted higher pull-out compared with MP/GC for both abutment heights before and after fatigue. Higher abutment height increased pull-out regarding lower abutment height for SU/RU materials before and after fatigue testing. Although fatigue had no significant effect on the pull-out of MP/GC, lower bond retention was observed for SU/RU after fatigue, regardless of abutment height. Luting agent composition and the interaction with abutment height and fatigue influenced the retention of zirconia crowns to titanium base abutments. [ABSTRACT FROM AUTHOR]

Recently, hybrid materials have been introduced to the dental market. Together with computer-assisted design/computer-assisted manufacturing (CAD/CAM) composite resins, they form a new class of dental CAD/CAM materials that combine the positive effects of ceramics and composites. As bonding is essential for their clinical longevity, it is crucial to have a good understanding of their material properties and cementation protocols. This review offers clinicians an overview of available hybrid materials and recommendations for their respective adhesive placements. [ABSTRACT FROM AUTHOR]

Dental erosion is a global oral health problem that can lead to significant functional and esthetic impairments of the affected patients. Treatment of severe cases with augmented loss of the vertical dimension of occlusion (VDO) represents a challenge for both the dental team and the patient. CAD/CAM technology was used in the presented case to analyze the interocclusal space. Based on a virtual wax-up of the final restorations, CAD/CAM-fabricated preparation splints served as a guide and ensured a most minimally invasive preparation design. Milled polymer provisionals enabled the patient to visualize the final treatment outcome and served as a fracture-resistant temporary restoration to test the increased VDO. Monolithic lithium-disilicate ceramic, defect-oriented restorations with reduced ceramic thickness enabled a functional and reliable reconstruction of the severely compromised dentition. This case report documents a practical, digital approach and discusses the advantages related to treatment time, ease of treatment, and predictability. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Overview Conclusion To investigate the nature and availability of evidence on the clinical performance of posterior partial coverage restorations (PCR) fabricated from different ceramic materials, outcome definitions, measurement methods, study drop‐outs and follow ups.A systematic literature search (inception‐February 2024) was performed through MEDLINE, Scopus, CENTRAL, ClinicalTrials.gov, and the International Clinical Trials Registry Platform to identify clinical studies with a focus on posterior PCRs (onlays, occlusal veneers and partial crowns) with a minimum follow‐up of 1 year. Thirteen of 31 included studies were randomized controlled trials (RCT) and 18 non‐randomized studies of intervention (NRS). Six RCTs compared two different ceramic materials and might be suitable for meta‐analysis. Differences in study design, definition of survival, evaluation methods, and statistical models for survival analysis were identified as reasons for expected heterogeneity among studies. The most common reasons for restoration failures were ceramic fractures and retention loss.The evidence informing the effect of PCRs varied in definitions of survival and failure, complication classifications, and workflow approaches. RCTs addressing clinical performance of PCRs comparing different ceramic materials are available for conducting systematic reviews and meta‐analyses. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Materials and Methods Results Conclusion Clinical Significance To determine the clinical performance of partial coverage restorations (PCR) (onlays, occlusal veneers, and partial crowns) composed of different ceramic and ceramic‐based materials to treat extended posterior defects.MEDLINE, Scopus, CENTRAL, ClinicalTrials.gov, and the International Clinical Trials Registry Platform were searched (inception‐February 2024) for randomized controlled trials (RCT) comparing posterior PCRs composed of different ceramic and ceramic‐based materials with a minimum follow‐up of 1 year.Six RCTs were included. Resin matrix ceramic (RMC) and lithium disilicate (LDS) restorations had a 3‐year survival rate of 89.3% (95% CI 76.4–95.3) and 93.7% (95% CI 83.7–97.7), respectively, and leucite‐reinforced glass ceramic (LRGC) restorations a range between 96.1% (95% CI 90.1–98.9) compared with RMC and 98.3% (95% CI 90.8–100) compared with LDS. After 1–3 years of follow‐up, LDS slightly outperformed RMC on restoration failure and loss of retention (1.56 more failures and 1.78 more loss of retentions for RMC per 100 restoration‐years [low certainty evidence]). No statistically significant differences between ceramic and ceramic‐based materials were detected in short‐term follow‐up (1–3 years of follow‐up). The long‐term performance of posterior PCRs is uncertain.The survival of LDS restorations may slightly outperform RMC restorations after 3 years of follow‐up across outcomes, except for bulk fracture. RCTs providing medium to long‐term data are needed.Ceramic and ceramic‐based PCRs are a reliable treatment option to restore extended posterior defects. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the available evidence on the accuracy of conventional and digital workflows for complete arch implant supported frameworks. Materials and methods: This scoping review was conducted according to the 5-stage framework of Arksey and O'Malley. A systematic literature search was performed adhering to the PRISMA guidelines to identify studies with a direct comparison of conventional and digital methods for the fabrication of complete arch implant supported frameworks. 58 in-vitro studies with the focus on edentulous arches with at least four implants published between 2000 and 2024 were included. The reported outcomes were examined to determine the value of a statistical analysis for adding up the individual errors to a cumulative error of the workflow. Results: Evidence on the accuracy assessment of digital and conventional workflows for complete arch implant supported frameworks is available. However, also studies with the same assessment methods and outcome units appear to be too heterogeneous to perform a statistical analysis of error accumulation. While there is no consensus in the impression and cast fabrication stage, digital techniques show a superior accuracy for the fabrication of complete arch implant supported frameworks compared to conventional casting. Conclusion: In-vitro studies assessing the accuracy of entire workflows and classifying their outcomes regarding the clinical relevance are lacking.