Deep margin elevation in class II cavities: A comparative evaluation of microleakage and interface integrity using confocal laser microscopy and scanning electron microscopy.

Aim: This study aims to evaluate the microleakage between the gingival seat and base material and to assess the interface integrity between the base material and overlying composite in class II cavities restored using deep margin elevation. Materials and Methods: Thirty maxillary molars (n = 30) were taken, and class II cavities were prepared with a gingival seat extending below the cementoenamel junction. These teeth were divided into three groups for subgingival margin elevation using different materials: Group A (n = 10) - flowable composite, Group B (n = 10) - glass ionomer cement (GIC), and Group C (n = 10) - GIC with nanohydroxyapatite (GIC n-HAp). The remaining cavities were restored with bulk-fill composite. After undergoing 1000 thermocycling cycles, half of the samples were examined for microleakage using confocal laser microscopy, and the other half were assessed for interface integrity using scanning electron microscopy. Microleakage was statistically analyzed by one-way ANOVA, and interface integrity was analyzed by Kruskal-Wallis tests. Results: The study found that GIC n-HAp exhibited significantly lower microleakage between the base material and gingival seat than flowable composite and GIC. However, regarding interface integrity between the base material and bulk-fill composite, flowable composite, and GIC outperformed GIC n-HAp. Conclusions: Incorporating n-HAp into GIC effectively reduced microleakage at the dentin-base material interface. However, the interface integrity between GIC n-HAp and the composite poses a challenge.

Evaluation of the efficacy of a novel disinfecting material on the surface topography of gutta-percha: An in vitro study.

Context: The effect of chemical disinfection on gutta-percha (GP) has to be closely studied whether it affects surface topography and thereby causes leakage and reinfection of canals. Aims: The purpose of the study is to assess the surface topography of GP cones after disinfecting with a novel disinfecting material, graphene oxide (GO), and compare the same with other disinfecting materials, including sodium hypochlorite (NaOCl) and silver nanoparticles (AgNps). Settings and Design: After determining the power (0.84) of the study, 48 GP cones were taken and categorized into four different groups based on disinfecting agents. Materials and Methods: Forty-eight GP cones (ISO size 30 6% taper, DIADENT) were taken and are randomly selected and grouped as follows according to the disinfecting agents: Group 1 - control (untreated GP points, n = 12), Group 2 - NaOCl (n = 12), Group 3 - AgNPs (n = 12), and Group 4 - GO (n = 12), respectively. After treating with the above disinfecting materials, the surface topography of samples was evaluated using atomic force microscopy. The data were analyzed statistically using one-way ANOVA and post hoc (Tukey's honestly significant difference) tests. Statistical Analysis Used: IBM SPSS (version 21.0) software was used. The tests performed were one-way ANOVA and post hoc. Statistically, significance was set at a P ≤ 0.05. Results: The root means square values and surface roughness values were lesser for the GO group and AgNPs when compared with the NaOCl group, which were statistically significant. Conclusions: Within the limitations of the study, this study had shown lesser surface topography deterioration of GP cones when treated with GO and AgNPs, whereas more deterioration was observed with NaOCl.

Effect of Different Irrigating Solutions on Depth of Penetration of Sealer into Dentinal Tubules: A Confocal Microscopic Study.

AIM: The aim of the study was to evaluate the effect of different irrigating solutions used in final irrigation on depth of sealer penetration into dentinal tubules. MATERIALS AND METHODS: Thirty recently extracted, human mandibular premolar teeth with single canals were randomly divided into two groups, and one of the two irrigants was used in each group - Group A (Chitosan) and Group B (Ethylenediaminetetraacetic acid). All the teeth were obturated with gutta-percha and AH 26® sealer labeled with fluorescent dye. The teeth were sectioned at distances 2, 5, and 8 mm from the root apex. Maximum depth of sealer penetration was measured using confocal laser scanning microscopy. STATISTICAL ANALYSIS: Statistical analysis used One-way analysis of variance and t-test. RESULTS: At coronal third depth, the sealer penetration was greater in ethylenediaminetetraacetic acid (EDTA) group; however, depth of sealer penetration was greater at apical third in chitosan group. CONCLUSION: Final irrigation with EDTA and chitosan after the use of sodium hypochlorite affected sealer penetration.