Comparative Evaluation of Thermal Stability of Root Canal-treated Teeth Filled Using Three Different Sealers by Thermogravimetric Analysis – An Ex vivo Study

A BSTRACT Background: Forensic experts can employ thermogravimetric analysis (TGA) to evaluate the root canal sealers’ heat resistance and degradation properties. This analysis provides vital insights into the temperature thresholds at which these sealers decompose or experience mass loss. Understanding potential alterations in dental materials used to restore fire victims’ dental defects is crucial for accurate identification. Factors such as root canal anatomy, treatment materials, and radiographs play significant roles in the identification process. Given the current trend favoring more sealer and less gutta-percha in root canal treatments, this study aims to assess three different types of sealers when exposed to high temperatures. The findings will enhance our understanding of root canal sealer properties and their responses to temperature variations. The null hypothesis posits that there are no differences in the mean values among the three groups (sealants), whereas the alternative hypothesis suggests that at least one group’s mean differs from the others. Objective: The objective of this study is to assess the properties of different sealers, such as the bioceramic BioActive RCS, resin-based AH Plus, and GuttaFlow2 containing bioceramic components using TGA. Materials and Methods: In this study, single-rooted mandibular premolars ( n = 4) were selected. Each sample was sectioned at the cementoenamel junction and treated with root canal therapy, using three different sealers; one sample remained untreated as a control. The middle third of each root was then sliced. All samples were subjected to TGA up to 1000°C. Intragroup differences were assessed with a paired t -test, while one-way ANOVA and Tukey’s post hoc test were used for intergroup comparisons. Results: Control teeth showed a 30% weight loss from 30°C to 1000°C, indicating significant degradation. Teeth filled with bioceramic sealer had a 28% weight loss, while those with GuttaFlow2 sealer had the least weight loss at 25%, suggesting superior thermal stability. Resin-sealed teeth showed a 29% weight loss, performing better than the control and bioceramic groups. Overall, GuttaFlow2 demonstrated the highest thermal stability, followed by resin and bioceramic sealers, with the control tooth being the least stable. Intragroup comparison showed significant differences ( P = 0.001), while intergroup comparison showed no significant differences ( P = 0.83). Conclusion: GuttaFlow2 displayed the highest thermal stability, followed by AH Plus and BioActive RCS. This ability to withstand high temperatures implies its potential usefulness as evidence in forensic identifications related to fires, highlighting the importance of root canal fillings in forensic investigations.