The Impact of Gastric Juice on the Surface Roughness of Surface Sealant-Treated Provisional Restorations.

BACKGROUND AND AIM: Gastroesophageal reflux disease causes gastric acid to enter the oral cavity, leading to mucosal changes and deterioration of dental hard tissues and materials. The purpose of this in vitro study was to evaluate the impact of gastric juice on the surface roughness of two types of acrylics used in provisional restorations. MATERIALS AND METHODS: Acrytemp ® and Temdent acrylic resin discs (10 × 2 mm) totaling 80 were manufactured and divided into eight groups (n = 10). Groups were prepared as follows: Group 1 (Temdent + Universal Polish) (control), Group 2 (Temdent + Universal Polish + Biscover LV), Group 3 (Temdent + Universal Polish + Resin Glaze), Group 4 (Temdent + Universal Polish + Fortify Plus), Group 5 (Acrytemp + Universal Polish) (control), Group 6 (Acrytemp + Universal Polish + Biscover LV), Group 7 (Acrytemp + Universal Polish + Resin Glaze), and Group 8 (Acrytemp + Universal Polish + Fortify Plus). The resin discs were immersed in distilled water for 24 h and in gastric juice (pH = 2) for additional 24 h. The initial and final roughness values of samples were measured and analyzed with non-parametric statistics including Mann-Whitney U-test for pairwise comparison, Kruskall Wallis test for comparing more than two groups, and Wilcoxon signed rank test for within-group comparison (P < 0.05). RESULTS: Surface roughness did not differ significantly between control groups. It notably increased for all samples with surface sealants, both initially and after gastric juice immersion (P < 0.05). CONCLUSION: Surface sealants noticeably increased the roughness of two types of acrylic resins. After immersing in gastric juice, Group 4 (Temdent + Universal Polish + Fortify Plus) showed the highest roughness, while the untreated control groups remained the smoothest.

Evaluation of color change before and after polymerization of laminate veneer restorations: A clinical study.

Background and Aim: The purpose of this in vivo study was to investigate the effect of translucent adhesive resin cement on the final color of ceramic laminate veneer restoration before and after polymerization in intraoral conditions. Materials and Methods: This study was conducted in 92 ceramic laminate veneer restorations of 27 patients. The ceramic laminate veneer restorations in standard thickness lithium disilicate ceramic structure (IPS e.max Press HT, Ivoclar Vivadent) were cemented to the tooth with translucent light-polymerized resin cement (Choice 2 Starter Kit, Bisco). Results: It was observed a clinically noticeable color change between ΔE values before and after polymerization (ΔE >3.3). There was a statistically significant difference in b* values, ΔL value, and Δb value. Conclusion: Within the limitations of this in vivo study, the results suggest that light polymerization of the translucent resin cement (Choice 2, Bisco) used is an important factor for the final color of the restoration and should be considered during shade selection and fabrication.

Deproteinization treatment on bond strengths of primary, mature and immature permanent tooth enamel.

OBJECTIVE: The aim of this study was to examine the effect of pre-post deproteinization treatment with 5% sodium hypochloride on shear bond strength (sbs) of adhesive resin to primary, immature and mature permanent teeth enamel. METHOD: 30 teeth were used for each of primary, immature and mature permanent teeth groups. (totally 90). In control groups, enamel was etched for 60s with 37% phosphoric acid (3M) and rinsed for 10s (Procedure A). In experimental groups, deproteinization was applied with 5% NaOCI solution for 120s before (Procedure D+A) and after acid-etching (Procedure A+D). Gluma Comfort Bond (Heraeus-Kulzer) and Charisma (Heraeus-Kulzer) composite resin were applied to etched enamel surfaces. Data were determined with Two-Way ANOVA and LSD Multiple Comparison Test (p < 0.05). RESULTS: SBS was significantly lower in primary and immature permanent teeth than mature permanent teeth (p < 0.05). "Procedure A+D" statistically increased sbs values in primary and immature permanent teeth (p < 0.05). CONCLUSION: Deproteinization after acid etching significantly enhanced the shear bond strength values in primary and immature permanent teeth.