Elkaffas AA, et al. Restor Dent Endod. 2019 May;44:e41. https://doi.org/10.5395/rde.2019.44.e41

In recent years, laminate veneer restorations should be considered as a minimally invasive treatment option for several aesthetic reasons. This study compared direct composite veneers’ and indirect ceramic laminate veneers’ longevity in multiple diastema closures. A total of 28 patients with a mean age of 26 years received 60 direct resin composite (Estelite Asteria; n = 14) and 60 indirect ceramic veneers (IPS e.max Press; n = 14) on the maxillary anterior teeth with diastema closure. Veneers were evaluated at baseline and thereafter every 6 months for up to 2 years using USPHS criteria. Data were analyzed with Fisher’s exact and chi-squared tests, while Kaplan–Meier curve was used to assess time to event. In total, three failures were observed in the form of debonding (n = 1) and fracture (n = 2) in the indirect ceramic veneers. No significant difference was observed between the survival rates of composite and ceramic veneers (Estelite Asteria: 93.4%, IPS e.max Press: 95%; p > 0.05). The overall survival rate was 94.2% (Kaplan–Meier). Staining (n = 11) and roughness (n = 14) were frequently observed for the resin composite veneers up to the final recall. Thereby, the preliminary results from this clinical trial comparing two veneer materials indicated that their survival rates were statistically similar. However, surface quality changes were more frequent in the composite veneer material.

Additive manufacturing (3D printing) using Computer-Aided Design (CAD) has emerged as a cost-effective alternative to subtractive milling in restorative dentistry, offering reduced material waste and lower production costs. This study aimed to compare the physical properties, specifically water sorption, water solubility, and surface roughness, of milled and 3D-printed hybrid resin composite materials. Standardized disk-shaped samples were fabricated using a digital workflow. The additive group included 15 samples printed with a DLP printer using CROWNTEC resin at three different orientations (0°, 45°, and 90°), with five samples prepared at each printing orientation. The subtractive group consisted of specimens milled from the SHOFU DISK hybrid resin composite. Surface roughness samples were also prepared for both methods. Statistical analysis using one-way ANOVA, post hoc tests, and paired t-tests revealed significant differences among groups in all tested properties (p < 0.001). Subtractive manufacturing consistently outperformed additive techniques. Among the printed groups, orientation at 0° showed the most favorable outcomes. Moreover, polishing significantly improved surface roughness in both manufacturing methods (p < 0.001). These findings emphasize the influence of the fabrication method and printing orientation on the clinical performance of hybrid resin composites, highlighting the importance of polishing in optimizing the surface quality for 3D-printed restorations.

The current study aimed to compare the mechanical properties of CAD/CAM fabricated hybrid ceramic restorative materials. The current study assessed the mechanical properties of additively and subtractively manufactured CAD/CAM fabricated hybrid ceramic by conducting flexure strength test, compressive strength test, and Vickers hardness test. Flexural samples were subjected to a three-point bending test using a universal testing machine until the samples showed fracture. Moreover, samples for the compressive strength test were subjected to compression tests using a universal testing machine until samples were fractured. Samples for the Vickers hardness was tested using the Vickers hardness testing machine to determine the sample’s hardness values. There were significant differences (p = 0.0001) were observed among the additive and subtractive groups in terms of flexure strength and compressive strength test. Regarding the Vickers hardness test, significant differences (p = 0.0001) were observed between the polished and unpolished groups in additive manufacturing. However, no significant (p = 0.681) differences were observed in the subtractive manufacturing technique. The subtractive group achieved ISO specifications in terms of flexural strength and was superior to additive groups in hardness while exhibiting lower performance in compressive strength. Moreover, printing orientation had a significant influence on the performance of additive groups. Flexural strength and hardness were improved when the printing orientation was in alignment with the direction of load (90°) while compressive strength was improved when the printing orientation was perpendicular to the direction of load (0°).