Radiographic Assessment of 121 Glass Fiber Post Procedures in 32 Patients Aged 21-60 Years Performed by 6th-Year Dental Students During the 2022-2023 Academic Year at the College of Dentistry, Jazan University, Saudi Arabia.

BACKGROUND The restoration of endodontically treated teeth (ETT) and severely damaged teeth has been a concern of clinicians. Glass Fiber Post (GFPs) combine the strength of carbon fiber posts with the esthetic appearance of glass to resemble natural dentin during dental restoration procedures. This radiographical study assessed the GFP carried out by students enrolled in the Clinical Comprehensive Course at the College of Dentistry, Jazan University. MATERIAL AND METHODS A total of 32 patients treated by 18 6th-year dental students with 121 GFPs were assessed in this cross-sectional radiographic study. The assessment covered tooth type, arch, post-to-root width, length of post in relation to the crown and root lengths, amount of remaining gutta percha (GP), and gap between GP and post. Data were analyzed using SPSS, and associations between variables were determined using the chi-square test. RESULTS Maxillary teeth were the most frequently restored with posts (88.4%) with most being (58.7%) anterior teeth, and 50.4% of posts had widths that were one-third that of the root. The percentage of posts was twice (71.1%) or equal to (26.4%) the crown length, whereas two-thirds of the tested GFPs were >5 mm of the remaining GP. Significant differences were observed in location and position of teeth with post width, post length in relation to crown or root length, and amount of remaining GP, with P values of 0.018, 0.000, and 0.001, respectively. CONCLUSIONS The assessed radiographs revealed that the performance of sixth year students in accomplishment GFP radiographically was satisfactory and within the values recommended in the literature.

Comparison of color changes, fracture strengths, and failure modes of conventional endocrowns and endocrowns with different design modifications.

BACKGROUND: Endocrowns (ECs) are alternatives for rebuilding severely damaged teeth and show superior efficacy in molars over premolars. OBJECTIVE: The objective of this in vitro study is to evaluate the effects of different preparation designs with short pulp chambers on the mean color change (Δ⁢E), fracture resistance, and failure types of mandibular molar ECs. METHOD: A total of 40 extracted mandibular molars were treated endodontically and divided into four groups. Samples in groups 1, 2, 3, and 4 had occlusal preparation depths of 5 mm, 3 mm, 3 mm with ferrule, and 3 mm with boxes, respectively. The samples were immersed in coffee and their Δ⁢E values were measured by using the Commission Internationale de l'Eclairage color system. They were also subjected to a fracture test. Next, all specimens were examined visually under a stereomicroscope to evaluate their failure modes and identify their fracture origins. Data were entered and analyzed by using Statistical Package for Social Sciences. RESULTS: Among all groups, group 4 (3 mm + boxes) presented the highest Δ⁢E (4.15) after immersion in coffee. Moreover, ANOVA revealed that the Δ⁢E of group 4 (occlusal preparation depth of 3 mm with boxes) was significantly different (p< 0.05) from that of group 2 (3 mm + ferrule, 3.07). The EC with a 3 mm chamfer and ferrule showed the highest maximum load of 2847.68 ± 693.27 N, whereas that with a 5 mm chamfer finish line had a marginally reduced load at fracture of 2831.52 ± 881.83 N. The EC with a 3 mm chamber and boxes had a slightly increased maximum load of 2700.75 ± 436.40 N, whereas that with the 3 mm chamber had the lowest maximum load at fracture of 2385.97 ± 465.61 N. One-way ANOVA showed that different EC preparation designs had no effect on maximum fracture load (F [3,16] = 0.550, p= 0.6). CONCLUSION: The recorded Δ⁢E values of ECs in all groups were equal or marginally higher than the acceptable values. The EC with a 3 mm chamfer and ferrule displayed the highest mean maximum load. The EC with a 5 mm chamfer finish line had a marginally lower maximum load at fracture than other ECs. Failures, such as ceramic fracture, split fracture, and ceramic and tooth splitting above the cemento-enamel junction (CEJ) or vertically were predominant in samples with occlusal preparation depths of 3 mm with ferrule and 5 mm.

Comparative Analysis of Properties in Chairside Silicone Denture Liners versus Heat-Cured Molloplast-B: An In-Depth In Vitro Evaluation.

BACKGROUND We investigated the bond strength, tensile strength, and water absorption properties of 4 widely used chairside silicone long-term denture soft lining materials and compared properties with those of heat-cured silicone material. MATERIAL AND METHODS Four chairside materials (GC Reline Soft, Mucopren Soft, Sofreliner Soft, and Elite Soft Relining) and a heat-cured silicone material (Molloplast B) were investigated. For tensile and shear bond strength and tensile strength, samples were prepared according to the manufacturers' instructions and the testing machine used. For water absorption, IOS 1567 was followed to prepare specimens. Bond strengths were measured using a Lloyd Instruments materials testing machine. Ten specimens for each test were prepared for each soft liner, except for water absorption and solubility tests, for which only 5 specimens were prepared. ANOVA, Bonferroni, and Kruskal-Wallis tests were used to compare values of materials and assess changes over time. RESULTS There was strong evidence of differences in the properties between materials. GC Reline Soft showed comparable tensile bond (1.4±0.6 MPa), shear bond (1.1±0.4 MPa), tensile strength (5.44±0.98), water absorption (0.92±0.2 µg/mm³), and solubility values (0.3±0.2 µg/mm3) to that of Molloplast B (1.4±0.4; 1.6±0.5; 4.53±0.9 MPa, 1.7±0.3, and 1.0±0.3 µg/mm³, respectively). The water solubility of Sofreliner Soft was significantly lower (1.5±0.8 µg/mm³) than that of Molloplast B. CONCLUSIONS There were significant differences between some properties of 4 chairside denture soft lining materials and that of Molloplast B, which had higher shear and tensile bond strength than chairside denture silicone soft lining materials but had the highest water solubility.