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°).
The oral environment significantly influences the esthetic appearance of CAD/CAM provisional restorative materials. Therefore, a veneering layer is required. Bonding veneering resin composites to these materials presents challenges, particularly under conditions of thermal aging. This study evaluated the impact of various surface treatments and thermal aging on the bond strength between veneering resin and CAD/CAM provisional materials. Fifty disk-shaped specimens of each CAD/CAM material (CAD-Temp, Everest C-Temp, and PEEK), measuring 10 mm in diameter and 3 mm in height, were fabricated. After being ultrasonically cleaned, specimens were embedded in acrylic resin blocks, leaving one surface exposed for surface treatments. Specimens were assigned to five groups at random. Group C: no surface treatments applied; DB: mechanically roughened with a diamond bur; DB + TC: DB group subjected to 5000 cycles of thermocycling; SB: treated with aluminum oxide airborne abrasion; SB + TC: SB group subjected to 5000 cycles of thermocycling. After the surface treatments, the primer and resin veneering composite were applied to the specimens. The shear bond strength (SBS) was calculated using a universal testing machine and the mode of failure was evaluated with an optical stereomicroscope with 40× magnification. Scanning electron microscopy evaluation was conducted to examine the surface topography of the materials’ surfaces after surface treatments. C-Temp in the SB group exhibited the highest SBS values (20.38 ± 1.04 MPa), while CAD-Temp in the C group showed the lowest values (4.60 ± 0.54 MPa). PEEK recorded significantly higher SBS values in DB + TC and SB + TC groups (9.26 ± 1.07 and 12.92 ± 0.97 MPa, respectively) compared to CAD-Temp in DB + TC and SB + TC groups (6.04 ± 0.76 and 8.82 ± 0.86 MPa, respectively). C-Temp exhibited higher SBS without surface treatment (13.11± 0.55 MPa), whereas PEEK showed higher SBS after diamond bur roughening and air particle abrasion (10.87 ± 1.02 MPa, and 14.37 ± 0.98 MPa, respectively). The thermocycling significantly reduced SBS values for C-Temp in the DB + TC and SB + TC groups (11.18 ± 0.92, 15.56 ± 0.87 MPa, respectively) and CAD-Temp in the DB + TC and SB + TC (6.04 ± 0.76 MPa and 8.82 ± 0.86 MPa, respectively). Conversely, the thermocycling had no significant effect on SBS values for PEEK material in the air particle abrasion group (12.92 ± 0.97 MPa).
Background: In recent era, digitalization in the dental sciences has been observed in wide ranges. This cross-sectional study aimed to assess knowledge and practice of additive manufacturing (AM) in dentistry among university teaching faculty in Saudi Arabia. Methods: A questionnaire was prepared and validated to distribute to the different dental colleges in Saudi Arabia. The questionnaire was divided into three parts: demographic information, knowledge and practices of AM among the dental teaching faculty. After receiving all the responses, descriptive statistics were used for the frequency distribution of all the responses. Results: A total of 367 responses were received from the different faculty members. Most of the participants were male (67.30%), holding assistant professor (52.50%) positions in the field of prosthodontics (23.40%). In terms of knowledge, even though most of the participants were aware of AM (64.30%); however, do not understand the AM techniques (33.50). Moreover, 71.90% of the participants had no experience working with AM and only 13.60% of participants used AM in their respective dental colleges. Conclusion: AM techniques are not commonly used in the field of dentistry in Saudi Arabia; therefore, more platforms should have created to enhance the knowledge and practice of AM in the current population.
The aim of the study is to assess the impact of mechanical surface treatments on the shear bond strength (SBS) of orthodontic brackets bonded to three-dimensional (3D) printed and milled CAD/CAM provisional materials. Sixty cylindrical samples were fabricated for each provisional material. Samples were treated with one of the following surface treatments: aluminum oxide airborne particle abrasion, diamond bur rotary instrument roughening, and phosphoric acid etching (control). Stainless steel brackets were bonded to the samples, and then SBS was tested using a universal testing machine. SEM and digital microscopy were utilized to examine the bonding interface and the failure modes. Two-way ANOVA, one-way ANOVA, Tukey’s HSD, and independent sample t-tests were used for statistical analysis. Results revealed significant differences in SBS between 3D printed and milled samples and significant differences in SBS among most surface treatments, with rotary instrument roughening resulting in the highest values for 3D printed, while airborne particle abrasion leading for milled samples. Digital microscopy indicated that more adhesive remained on 3D-printed samples. SEM analysis revealed varying surface roughness across treatments. Based on the findings of this study, it can be concluded that different surface treatments improve the bonding of orthodontic brackets to provisional crowns.