Bioactivity of novel hydrated calcium silicate in dentin holes

Objectives: The aim of study was to evaluate the bioactivity of the experimental light curable hydrated calcium silicate as a pulp capping material.
Methods: The experimental light curing calcium silicate pulp-capping materials were composed with resin matrix and filler (50:50 by weight). The 10% was silanized glass powder and the other was mixture of hydrated and anhydrated calcium silicate powder. They were mixed 40/0, 30/10, 20/20, 10/30 and 0/40 and named H4, H3, H2, H1 and H0 respectively. The TheraCal^TM (TH, Bisco, USA) was used as a product control. Bovine dentin disk (diameter 10 mm, thickness 1 mm) with a hole of 1 mm diameter was attached to a same sized specimen and immersed the assembly in simulated body fluid. After 14 and 28 days, the hole of dentin disc was analyzed by image analyzer to measure occlusive area, by field emission scanning electron microscope (FE-SEM) and energy-dispersive x-ray spectroscopy (EDS) to characterize precipitations. The occlusive ratio was calculated by newly precipitated area/original hole area and the results were statistically analyzed with one-way ANOVA followed by Tukey.
Results: The results on day 14 were (89.5 ± 9.6), (82.9 ± 29.8), (99.4 ± 0.56), (37.9 ± 41.7), (0.49 ± 0.85), (15.1 ± 26.2) % in H4, H3, H2, H1, H0 and TH, respectively. In addition, the results on day 28 were (92.6 ± 10.1), (99.9 ± 0.17), (82.5 ± 4.24), (63.7 ± 38.9), (24.9 ± 43.2), (40.7 ± 42.8) % in H4, H3, H2, H1, H0 and TH, respectively. Nevertheless immersion time, the H0 and TH showed significantly lower value than other groups (p<0.05).
Conclusions: The higher contents of hydrate calcium silicate filler groups showed more bioactive. In addition, we assumed that the dentin-hole model has potential to be used as new bioactive model.