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Background/Aim: 3D printing processes can be used to manufacture custom‐made mouthguards for sports activities. Few studies have compared the impact performance of industrial‐created mouthguards with that of custom‐made mouthguards manufactured by thermoforming or 3D printing. The objective of this in vitro study was to compare the shock absorption capacities of custom‐made mouthguards manufactured by 3D printing with industrial mouthguards and thermoformed ethylene vinyl acetate (EVA) mouthguards. Materials and Methods: For each type of mouthguard, eight samples were produced. 3D‐printed mouthguards were manufactured using digital light processing technology. Each mouthguard was subjected to an impact performance test defined by the standard AFNOR XP S72‐427, which evaluate maximum deceleration and force transmitted during impact. The thickness of each mouthguard before and after a series of five impacts was measured at the impacted inter‐incisal area. Results: The mean maximum decelerations during impact ranged from 129 to 189 g for industrial mouthguards, 287 to 425 g for thermoformed EVA mouthguards, and 277 to 302 g for 3D‐printed mouthguards. The mean reduction in mouthguard thickness at the impact zone after five tests was 1.2 mm for industrial mouthguards, 0.6 mm for 3D‐printed mouthguards, and 2.2 mm for thermoformed EVA mouthguards. Conclusions: Custom‐made 3D printed mouthguards showed slightly better shock absorption ability than thermoformed mouthguards with respect to the indicator proposed in XP S72‐427. They seemed to combine the practical advantages of thermoformed mouthguards in sports with better shock absorption capacity and lower cost. Furthermore, they had the least thickness variation during the test, and their shock absorption capacity was the least affected by repeated mechanical tests. Other types of 3D‐printing resin materials that will become available must continue to be tested for shock absorption to provide the best protection to users at low cost. [ABSTRACT FROM AUTHOR] more...

The study assessed the depth of cure (DOC) of different resin composites light-cured through different types of CAD/CAM materials of variable thickness. Three CAD/CAM materials (multilayer zirconia, lithium disilicate glass ceramic, composite) of three thicknesses (2-, 3-, and 4-mm) were prepared and their translucency parameter (TP) were measured. A light-curable and a dual-curable resin cement (Variolink Esthetic LC and DC) and a bulk-fill resin composite with a higher Ivocerin concentration (Tetric PowerFill) were used to mimic luting agents. DOC was assessed via Vickers microhardness testing. Increased thickness of CAD/CAM specimen was associated with decreased DOC. The chemical composition of the resin composites affected their curing performance depending on the light curing mode. Tetric PowerFill presented the greater DOC among the other resin composites. Receiver operating characteristic models of curing status appeared to provide better insight in predicting the DOC of luting agent according to TP than linear regression. [ABSTRACT FROM AUTHOR] more...

Purpose/objectives: Treating intraosseous lesions (IOLs) and interradicular bone lesions (IRLs) is an extremely technical dental procedure in periodontics. Instrumentation of these lesions is often perceived as difficult by students and inexperienced dentists before they perform a certain number of procedures on patients in the clinic. The aim of this article is to evaluate a cost‐effective three‐dimensional (3D)‐printed educational simulator for the periodontal treatment of IOLs/IRLs (including scaling, incisions and sutures). Methods: The simulators were first developed digitally, and then manufactured using printable resins and specific materials; finally, they were assembled using different bonding systems. To evaluate the simulators, assessments were gathered from two target populations: undergraduate students and periodontics experts. These individuals tested the simulator and completed a cross‐sectional questionnaire based on a Likert scale with comparative and pedagogical items scored from one to five. The purpose of the questionnaire was to compare our simulator to clinical reality (i.e., operation on human jaws) and to an animal simulator (i.e., simulation of porcine jaws). The results are expressed as the mean and standard deviation and were statistically analyzed with the Wilcoxon signed‐rank test. Results: Overall, the results were satisfactory for both groups of testers (4.70 and 4.61 out of five for students and experts, respectively, for global satisfaction). Conclusions: The overall educational relevance of the simulator designed herein highlights the fact that 3D‐printed educational simulators could enable efficient cognitive‐functional learning for clinical IOL/IRL treatment. [ABSTRACT FROM AUTHOR] more...

The restoration of endodontically treated teeth (ETT) remains a significant challenge in modern dentistry. These teeth often suffer from substantial structural damage due to both the original pathology and the invasive nature of endodontic procedures. Consequently, ETT are more susceptible to fractures compared to vital teeth, necessitating restorative strategies that can effectively restore both function and aesthetics while minimizing the risk of failure. In recent years, advances in adhesive dentistry and the development of high-strength ceramics have further expanded the restorative options for ETT. Bonded restorations have gained popularity as they preserve more tooth structure and enhance the overall strenght of the tooth-restoration complex. The choice of restorative material and technique is influenced by numerous factors, including the amount of remaining tooth structure, the functional requirements of the tooth, and the aesthetic demands of the patient. Despite the plethora of available materials and techniques, the optimal approach to restoring ETT remains a topic of ongoing research and debate. In this comprehensive review, the current state of and recent advances in restoring damaged endodontically treated teeth are explored. Numerous therapeutic options exist, involving a wide range of materials. This article aims to present the biomaterial advancements of the past decade and their applications, offering alternative approaches to treating damaged ETT with the goal of prolonging their retention on the dental arch and serving as a valuable resource for dental practitioners who face this issue daily. [ABSTRACT FROM AUTHOR] more...

Purpose: The aim of this study was to investigate the dentin shear bond strength (SBS) and bonding interface of three recently developed "universal" resin luting cements based on different modalities. Methods: The dentin SBS and interfacial analysis of three recently launched "universal" resin luting cements, namely, G-Cem One, RelyX Universal and Panavia SA cement universal, were studied. All bonding protocols, including the previous use of their dedicated primer or universal adhesive in touch-cure mode or light-cure mode were performed. Variolink Esthetic LC used in conjunction with Scotchbond Universal Plus was used as a control group. For each group (n = 9), 10 specimens were tested for dentin SBS and two were examined by scanning electron microscopy. SBS were analyzed by two-way ANOVA followed by Dunnett's test. Results: SBS values showed that the three "universal" resin luting cements tested exhibit different adhesive behaviors. G-Cem One with its touch-cure activated primer had a greater SBS to dentin (25.5 MPa) than that of the control group (22.1 MPa). Conclusion: "Universal" resin luting cements have variable efficacy when used in self-curing mode. The touch-curing mode is also of concern but may show high potential for some formulations. [ABSTRACT FROM AUTHOR] more...

Key Clinical Message: Treatment of patients with amelogenesis imperfecta extends over many years, from childhood to early adulthood. Their management at any age is complex and has to be adapted in relation to therapies validated in the general population. [ABSTRACT FROM AUTHOR] more...

Key Clinical Message: The cantilevered fixed partial denture (CFPD) is gaining recognition as a sound method of replacing missing teeth in the posterior sector. The purpose of this case report is to demonstrate that this type of restoration can be performed in a single appointment. A 39‐year‐old patient presented herself to the dental department; she showed agenesis of the two first maxillary premolars with a totally closed mesio‐distal gap and a recent loss of the 2 s maxillary premolars. This case report concerns the replacement of the upper left second premolar. The patient was treated with a mesial CFPD resting on an "onlay‐like" retainer on the first molar and replacing the missing premolar with a cantilevered pontic. The dimensions of the connection's cross‐section were maximized as much as possible (>20 mm2). The restoration was designed and produced using chairside CAD‐CAM from a milled‐reinforced glass–ceramic block (Emax CAD, Ivoclar Vivadent). The aesthetic and functional integration of the prosthesis was successful. The patient was examined at 11 months for a follow‐up. At this early stage, satisfactory dental hygiene was observed, associated with a smooth prosthetic fit, no periodontal inflammation, normal probing, and no abnormal dental mobility. [ABSTRACT FROM AUTHOR] more...

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Purpose: To determine whether selective laser melting (SLM) is suitable for the fabrication of dental superstructures.Materials and Methods: Mechanical properties of Ti-6Al-4V, manufactured with SLM or numerically controlled milling, were evaluated and compared.Results and Conclusion: Both groups showed a mechanical strength greater than 500 MPa and an elongation greater than 2%, as required by the International Organization for Standardization 22674 standard. However, a reduced ductility was observed for SLM samples. [ABSTRACT FROM AUTHOR] more...

Purpose: To mechanically characterize and assess the biological properties of Ti6Al4V surfaces obtained by Selective Laser Melting in order to determine whether this process is conceivable for production of implant‐supported prostheses and particularly trans‐gingival components. As‐built and polished surfaces were studied in comparison with components obtained by computer numerical control machining technology in order to consider whether the properties are in the same range as the conventional method currently used. Materials and Methods: Cylindrical specimens of Ti6Al4V (n = 6) were built with Selective Laser Melting for the characterization of mechanical properties according to ISO 22674 and discs (n = 12) were fabricated in the same conditions for cytotoxicity evaluation. Discs (n = 12) of Ti6Al4V were also obtained by computer numerical control machining as control. Half of the number of discs (n = 6) from each process were polished, to simulate the laboratory protocol for polishing of transmucosal components and half of the discs remained unaltered (as‐built). Surface roughness measurements of disc specimens (as‐built and polished) were compared with computer numerical control milling specimens (as‐built and polished). Proliferation of human gingival fibroblasts on Ti6Al4V surfaces was also assessed for each condition. Viability and cell morphology were then evaluated qualitatively. Ra and Sa data were compared using Student's t‐test (α = 0.05) and metabolic activity data were compared using Kruskal‐Wallis statistical test (α = 0.05). Results: Selective Laser Melting specimens showed elongation at break greater than 2% and 0.2% yield strength better than 500MPa which complied with ISO 22674 standards. Although Selective Laser Melting samples displayed significantly increased roughness on as‐built surfaces compared to computer numerically controlled milling samples (p < 0.05), no statistically significant difference was observed after mechanical polishing (p = 0.279). Regarding metabolic activity, no statistical difference was observed between groups at day 3 (p > 0.05) and fibroblasts showed a viability higher than 97% on all discs. Cell shapes on polished samples suggested moderate adhesion compared to unpolished samples. Conclusion: With the manufacturing parameters selected in this study, Selective Laser Melting of Ti6Al4V appeared to be compatible with a prosthetic application type 4 according to ISO 22674. Surfaces obtained, followed by recommended postprocessing provided components with equivalent biological properties compared to computer numerical control machining technology. [ABSTRACT FROM AUTHOR] more...