Evaluation of the Effect of Nanohydroxyapatite-containing Varnish on Remineralization of Early Enamel Caries and Occlusion of Dentinal Tubules

Various factors contribute to tooth decay. Modern dentistry suggests different ways to enhance remineralization and prevent caries progression. The present study aimed to evaluate the effect of nano-hydroxyapatite toothpaste and mouthwash on the remineralization of primary enamel lesions and occlusion of dentinal Tubules.

A total of 45 extracted human central teeth were used in this study. Artificial decay was induced by placing samples in a demineralization solution in an incubator at 37°C for 72 h. The hardness of four samples of demineralized teeth was determined by a microhardness test. The samples were divided into three equal groups according to the table of random numbers. The samples were subjected to pH cycling for 14 days, which included 3 and 21 h of demineralization and remineralization, respectively. SEM and Vickers microhardness tests were performed and the results were compared and the degree of occlusion of dentinal tubules was reported. Then the results were analyzed using SPSS software (version 24) and descriptive statistics, ANOVA, and Tukey's multiple comparison test.

The results of repeated measures ANOVA indicated a statistically significant difference in microhardness changes between the studied groups (P=0.006). Also, in-group analysis of microhardness changes in the groups demonstrated a significant difference between these changes (P<0.0001).

According to the obtained results, using nanohydroxyapatite can considered as a therapeutic approach to repair decayed teeth and it increases dental microhardness when added to varnish.