Objective The main objective of the study was to compare two different remineralising materials containing casein phosphopeptide-amorphous calcium phosphate, bioactive glass on enamel surface microhardness. Materials and Methods Thirty premolars were used for specimen preparation. Group 1 (the control group) consisted of intact enamel samples, group 2: CPP-ACPF (Tooth Mousse Plus), group 3: bioenamel remineralising gel (Prevest DenPro). All specimens were subjected to demineralisation except the control group, followed by which remineralising agents were applied. A universal hardness tester was used to assess the surface microhardness of all samples. Results were analysed using one-way ANOVA test and comparison was analysed using Scheffe’s post hoc least significant difference (LSD) test. Results Both remineralising agents used in groups 2 and 3 have shown significant outcome in terms of improving the surface microhardness in comparison with the control group. Group 2 increased the enamel hardness by 8.34 where P = 0.023 whereas group 3 increased the hardness by 5.87, where P = 0.01. Conclusion Group 2 has a superior hardness value than group 3; however, no statistically significant results were obtained between both the groups.

Objective: This study aims to investigate and compare the establishment of dentinal cracks during root canal preparation using a stereomicroscope and a scanning electron microscope (SEM). Materials and methods: Sixty removed human mandibular premolars were separated into three groups of 20: two experimental and one control. Within the randomized controlled experimental groups, root canals were constructed. Group I: the Waldent walflex file and Group II: the Trunatomy (TRN) file. Group III: the control group received no preparations. The surfaces of the roots were checked for dentinal cracks using a stereomicroscope and SEM following sectioning at 3, 6, and 9 mm from the apex. The Chi-square test was used to examine the data. Results:​​​​​​ In the control group, no fissures appeared. Cracks in Waldent Walflex were almost 66.7% between the 3mm and 6mm range. At both the 6 mm and 9 mm levels, there was no statistically significant difference between the experimental groups (P > 0.05). Defects were found to be substantially higher in the apical region of samples than in the median and coronal sections. Conclusion: Dentinal fissures were created by every rotary file used in the tests. There were more flaws in the Waldent Walflex file group than in the Trunatomy file group.

Background: The objective of the study is to compare stress distribution in a tooth restored with everstick post and sharonlay by means of three-dimensional finite element analysis (3D-FEA). Materials and Methods: An experimental original study was carried out in which two 3D-FEA models were constructed: (1) tooth restored with everstick post and metal ceramic crown and (2) tooth restored with sharonlay. The material properties were assigned and a force of 100N, 200N, 300N, and 400N was applied to the centric stop of the occlusal surface in centric occlusion at a 45° inclination in a linguolabial direction to the long axis of the tooth. Analysis was run and the stress distribution pattern was studied. As all stress distribution analysis was performed with the Ansys 11.0 software (Inventor AutoCAD 2010; Autodesk) program, the significance of P value or tests for statistical analysis was considered. Results: Sharonlay showed more total deformation, larger stress, and strain concentration than that of everstick post. Conclusion: Tooth restored with sharonlay showed greater chances of deformation than everstick post. It also showed maximum strain concentration near the apical portion of the remaining tooth structure and more stress in the cervical third of the postsystem than everstick post.