New technologies are changing the therapeutical options to do indirect restorations and new adhesive systems are continuously introduced to be used by clinicians. Different interactions between restorations, adhesive systems components, enamel and dentin require having criteria based on the selection of the adhesive system, ensuring the longevity of the restorations and the preservation of the biological remnant. The adhesion force to the dental tissue is one of the indicatives of the behavior of the adhesive systems and influences the behavior of the treatments with direct and indirect restorations. The objective of this search was to find the adhesive systems with the best results in terms of the adhesion strength of indirect restorations on the dental tissues. The search was conducted in two MEDLINE digital databases (PubMed), and the Cochrane Library with a search strategy based on the combination of MeSH (Medical Subject Headings) keywords. This systematic review used the PRISMA guide (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). According to this review, the 3-step adhesive systems were the best performing and still are the gold standard for the cementing of indirect restorations. In addition, it can be concluded that self-etched adhesive systems reduce the time spent in clinical practice, however at the interface level they behave as permeable membranes more susceptible to degradation.

The aim of this study was to evaluate and compare the resistance to fracture of interim restorations obtained through additive techniques (3D impressions) and subtractive techniques (milling) using a computer-aided design and manufacture (CAD/CAM) system of a three-unit fixed dental prosthesis (FDP) to ascertain its clinical importance. (1) Materials and methods: In total, 40 samples were manufactured and divided into two groups (n = 20) using: (1) light-curing micro hybrid resin for temporary crowns and bridges (PriZma 3D Bio Prov, MarketechLabs, São Paulo, Brazil) for the rapid prototyping group (RP) and (2) a polymethylmethacrylate (PMMA) CAD/CAM disc (Vipiblock Trilux, VIPI, São Paulo, Brazil) for the computer-assisted milling (CC). The resistance to fracture was determined with a universal testing machine. (2) Results: The strength and the standard deviation for the computer-assisted milling group were higher (1663.57 ± 130.25 N) than the rapid prototyping (RP) group, which had lower values of (1437.74 ± 73.41 N). (3) Conclusions: The provisional restorations from the computer-assisted milling group showed a greater resistance to fracture than the provisional restorations obtained from the rapid prototyping group.

The development of digital technologies has allowed for the fabrication of new materials; however, it makes it difficult to choose the best methods to obtain occlusal splints with optimal properties, so it is essential to evaluate the effectiveness of these materials. The aim of the study is to compare the fracture resistance of occlusal splints made of different materials after thermo-mechanical aging. Methods: A total of 32 samples were made from 4 materials (two 3D printed polymeric materials, a PMMA disc for CAD/CAM, and a conventional heat-cured acrylic resin); subsequently, the fracture test was performed using the load compression mode applied occlusally on the splint surface. Statistical analysis: Four statistical tests were used (Shapiro-Wilk, Levene’s test, ANOVA, and Tukey’s HSD test). Results: The following study showed that there are differences in fracture strength among the four materials investigated, where the highest strength was observed in the milled splint, with a mean of 3051.2 N (newton) compared to the strength of the flexible splint with 1943.4 N, the printed splint with 1489.9 N, and the conventional acrylic splint with 1303.9 N. Conclusions: The milled splints were the most resistant to fracture. Of the printed splints, the splint made with flexural rigid resin withstood the applied forces in acceptable ranges, so its clinical indication may be viable. Although the results of this research indicated differences in the mechanical properties between the CAD/CAM and conventional fabrication methods, the selection may also be influenced by processing time and cost, since with a CAD/CAM system there is a significant reduction in the production time of the splint material.

Dental implant placement is crucial in oral rehabilitation, requiring precision for successful outcomes. Digital technologies, including surgical guides, enhance predictability and efficiency in implant procedures. However, their impact on implant positioning accuracy is still under investigation. This systematic review aimed to evaluate the literature on implant accuracy using digital prosthetically-derived surgical guides. Registered in PROSPERO (CRD 42023483194), the review employed a PICO strategy and searched PubMed for English-language, in vivo studies from 2013 to 2023 on restrictive digital prosthetically-derived surgical guides. Two reviewers independently assessed records, with a third verifying the decisions. PRISMA guidelines were followed, yielding 24 results after excluding nine duplicates. Ten studies met the criteria after title, abstract, and keyword review, with three included after verification. These studies showed coronal deviations of 0.44 mm to 0.56 mm, apical deviations of 0.64 mm to 1.03 mm, angular deviations of 2.03° to 2.42°, and vertical deviations of 0.19 mm to 0.45 mm. Superior accuracy was noted with static guided techniques, while bilateral guides offered stability and printed guides were cost-effective. A surgical guide that comes from a planning with a primary wax-up of the prosthesis leads to the placement of a dental implant that can be functionally and esthetically rehabilitated. Further research is needed to standardize outcomes and improve implant protocols and patient outcomes.

The aim of this study was to evaluate and compare the fracture resistance of a single-unit fixed prosthesis, using a CAD/CAM PMMA material and two printed materials (3DPPa and 3DPPb). A typodont with a specific preparation for a full crown was used; a digital impression was made with a state-of-the-art scanner (PrimeScan^TM, Dentsply-Sirona^TM, New York, NY, USA), and a full coverage restoration was designed using a biogeneric design proposal by means of specific software (InLAB 22.1, Dentsply-Sirona, NY, USA). Sixty crowns were prepared, divided into three groups according to the material: 3DPPa (n = 20), 3DPPb (n = 20), both 3D-printed from the .STL file with a resolution of 50 μm, and PMMA (n = 20) milled-derived, which were subjected to a thermocycling process. A universal testing machine (Universal/Tensile Testing Machine, Autograph AGS-X Series) with integrated software (TRAPEZIUM LITE X) equipped with a 20 kN load cell was used to determine the fracture resistance. Significant differences were found by Kruskal–Wallis test and multiple comparisons (p < 0.05) in fracture resistance between materials. The fracture resistance for the PMMA material was higher, and the standard deviation was lower (x = 1427.9; sd = 36.9 N) compared to the 3DPPa (x = 1231; sd = 380.1 N) and 3DPPb (x = 1029.9; sd = 166.46 N) prints. The restorations from the milled-derived group showed higher average fracture resistance than the provisional restorations obtained from the printed groups. However, the results demonstrated that all three materials analyzed in single-unit restorations are capable of withstanding the average masticatory forces.