Aim: This study was conducted to evaluate and compare fluoride ion release by Cention-N (self-cure and light-cure) and conventional glass-ionomer cement (GIC) at different pH and time intervals. Methodology: Cavities of similar dimensions were prepared in mandibular molars and restored with Cention-N (by self-cure and light-cure techniques) and GIC. Samples were stored in deionized water, and the cumulative fluoride ion release and change in pH were assessed utilizing spectrophotometer and pH meter, respectively, at the end of 7 days, 14 days, and 21 days. The data thus obtained were statistically analyzed. Results: All the tested materials released fluoride ions in both acidic and neutral pH at all time intervals, and the fluoride ion release was significantly higher (<0.05) in acidic pH as compared to neutral pH except in GIC. All the groups showed a statistically significant increase in pH in acidic medium, whereas no significant increase was observed in neutral medium. Conclusions: Cention-N (self-cure) has the highest fluoride ion release and alkalizing potential in acidic pH as compared to Cention-N (light-cure) and GIC.

Aim:The purpose of this study was to evaluate the effect of phytic acid, ethylenediaminetetraacetic acid (EDTA), and chitosan solutions on the microhardness of human radicular dentin.Materials and Methods:Thirty dentin specimens were randomly divided into three groups of 10 specimens each according to the irrigant used: G1 — 1% phytic acid, G2 — 17% EDTA, and G3 — 0.2% chitosan. A standardized volume of each chelating solution was used for 3 min. Dentin microhardness was measured before and after application at the cervical, middle, and apical levels with a Vickers indenter under a 200-g load and a 10-s dwell time. The results were analyzed using one-way analysis of variance (ANOVA) and Student's t test.Results:Microhardness of the radicular dentin varied at the cervical, middle, and apical levels. EDTA had the greatest overall effect, causing a sharp percentage reduction in dentin microhardness with a significant difference from phytic acid and chitosan (P = 0.002). However, phytic acid and chitosan differed insignificantly from each other (P = 0.887).Conclusion:All tested chelating solutions reduced microhardness of the radicular dentin layer at all the levels. However, reduction was least at the apical level. EDTA caused more reduction in dentin microhardness than chitosan while phytic acid reduced the least.

Aim: The aim is to compare and evaluate the different finishing and polishing systems for the change in surface roughness of resin composites and enamel. Materials and Methods: To conduct the study, 30 extracted human maxillary central incisors were selected, decoronated, and molded in self-cure acrylic molds. A box-shaped cavity of dimensions 3 mm × 3 mm × 2 mm was prepared in all the teeth. A nanohybrid composite resin (Filtek Z250) was then used to restore the prepared cavities. Thirty samples were divided into two groups, control group (Group A, n = 10) and experimental group (Group B, n = 20). The samples in Group A were cured through the Mylar matrix. The experimental group, i.e., Group B was divided into two subgroups, i.e., Subgroup BX, n = 10 in which Sof-Lex polishing system was used for polishing the tooth surface and Subgroup BF, n = 10 in which Shofu composite polishing system was used. The mean surface roughness (Ra in μm) of the composite restoration as well as for the enamel surface of all the samples before and after polishing was measured with a contact profilometer, and the values were correlated with scanning electron microscopy. Results: The statistical analysis was carried out using paired t -test. The results exhibited a significant decrease in the surface roughness of the resin composite and enamel surface irrespective of the finishing and polishing system used. The mean surface roughness values demonstrated by Mylar matrix was the lowest followed by Sof-Lex polishing system. Shofu polishing system demonstrated the highest surface roughness values. Conclusion: Finishing and polishing of composite restoration can achieve a surface roughness similar to that of enamel. Involvement of marginal enamel in finishing and polishing procedures carried out for composite restoration results in smoother enamel surface.

Aim:To compare the effect of three root canal sealer activation techniques on percentage and depth of sealer penetration of MTA Fillapex and AH Plus sealers.Materials and Methods:Sixty teeth prepared till F5 ProTaper size were divided into three equal groups on the basis of sealer activation technique (G1: Ultrasonics, G2: Lentulo spiral, and G3: Counter-clockwise rotary motion). Each group was further divided into two equal subgroups on the basis of type of sealer used: AH Plus (Denstply, Konstanz, Germany) or MTA Fillapex (Angelus, Londrina, PR, Brazil) and obturated with gutta-percha. Horizontal sections at 3 and 6 mm from the apex were obtained and the percentage and depth of penetration of sealers into dentinal tubules were measured using confocal laser scanning microscopy (CLSM). Statistical analysis was performed utilizing Kruskal-Wallis and Mann-Whitney U tests with a significance level of 5%.Results:G1 showed significantly (P < 0.001) high percentage and depth of sealer penetration than G2 and G3 while the difference was insignificant (P > 0.05) between G2 and G3.Conclusion:Percentage and depth of sealer penetration are influenced by the type of sealer used sealer activation technique and by the root canal level. Ultrasonic method of sealer activation and MTA Fillapex showed the best results.

Background:Sealers are used to attain an impervious seal between the core material and root canal walls.Aim:To compare the depth and percentage of sealer penetration with three different placement techniques using confocal laser scanning microscopy as the evaluative tool.Materials and Methods:Root canals of 30 single-rooted teeth were prepared to a size of F3 and AH plus sealer with Rhodamine B was applied with Ultlrasonic file (Gr-1), lentulospiral (Gr-2), and Endoactivator (Gr-3). Canals were obturated with gutta-percha. The roots were sectioned at the 3 and 6-mm levels from the apical foramen and were examined on a confocal microscope.Results:A statistical significant differences among Gr-1, Gr-2, and Gr-3 were found at the 3 and 6-mm level (P < 0.05; ANOVA-Tukey tests) for the depth and percentage of sealer penetration except for Gr-1 and Gr-2 at 3-mm level. Gr-1 showed maximum mean depth of penetration (810 μm) and maximum mean percentage of sealer penetration (64.5) while Gr-3 showed minimum mean depth of penetration (112.7 μm) and minimum mean percentage of sealer penetration (26.7).Conclusion:Depth and percentage of penetration of sealer is influenced by the type of placement technique and by the root canal level with penetration decreasing apically.