Short-term Effect of Four Root Filling Materials on the Flexural Strength of Human Root Dentin

Background: This study aimed to assess the effects of calcium hydroxide, Biodentine, calcium-enriched mixture (CEM) cement, and mineral trioxide aggregate (MTA) on root dentin flexural strength after a ۳۰-day exposure period.Methods: This in vitro experimental study evaluated ۲۵ freshly extracted sound human incisors with no caries or restorations. The apical ۵ mm and the coronal two-thirds of the crowns were cut such that all samples had ۱۰ mm length. Dentin samples (n=۲۰ in each group) were then exposed to ۲ mm thickness of calcium hydroxide, Biodentine, CEM cement, MTA, or saline (control) in petri dishes for ۳۰ days. Finally, dentin samples were subjected to a three-point bending test after the intervention, and the flexural strength data were analyzed using one-way ANOVA, Tukey’s test, and t test.Results: Thirty-day exposure to all four biomaterials decreased the flexural strength of root dentin (P < ۰.۰۵). The four groups were significantly different in terms of the flexural strength of root dentin (P = ۰.۰۰۱). The flexural strength of root dentin was significantly lower following exposure to calcium hydroxide (P = ۰.۰۰۳), Biodentine (P = ۰.۰۱۱), CEM cement (P = ۰.۰۰۱), and MTA (P = ۰.۰۰۷) compared to saline. The reduction in strength following exposure to calcium hydroxide was higher than that in Biodentine, CEM cement, and MTA groups (P < ۰.۰۵) while the latter three were not significantly different in this respect (P > ۰.۰۵).Conclusions: In general, all four tested biomaterials decrease the dentin strength although this reduction is more prominent by calcium hydroxide.

Keywords:

Root canal filling materials , Mineral trioxide aggregate , Biodentine , CEM cement , Calcium hydroxide , Dentin , Flexural strength