Effect of Gamma Radiation on Adaptability of Mineral Trioxide Aggregate (MTA) and Nano Mineral Trioxide Aggregate (Nano-MTA) as Root-End Filling Materials (An In vitro study)

This study aimed to assess and compare the effect of gamma irradiation on the marginal adaptability of mineral trioxide aggregate (MTA) and Nano-MTA to root-end cavity walls using scanning electron microscopy (SEM). Twenty-eight extracted human single-rooted teeth were divided into two groups (n=14 each): Non-irradiated, irradiated group, then each group was subdivided according to the material used MTA and Nano-MTA. Irradiated groups were exposed to a fractionated dose of 60 Gy to simulate clinical radiotherapy. Root-end resections and standardized retrograde cavity preparations were performed, followed by root-end filling with either MTA or Nano-MTA. Samples were stored in physiologic saline at 37°C. Transverse sections were prepared and examined using scanning electron microscope. Data were statistically analyzed using ANOVA and Tukey’s post-hoc tests. Irradiated samples showed wider marginal gaps than non-irradiated groups with no statistically significant difference. Among all groups, Nano-MTA exhibited superior marginal adaptation with less size of gaps than conventional MTA, particularly in the non-irradiated group. Nano-MTA showed better marginal adaptation over conventional MTA, even after exposure to gamma irradiation suggesting its potential as a more effective root-end filling material.