Pulp Reaction to Bioceramics Combined with Low-Level Laser application

Objectives: The aim of this study was to investigate pulpal reaction towards EndoSequence Bioceramic Root Repair Material (ERRM; Putty), after low-level laser application.
Methods: Eighty teeth in 8 Canaan dogs were randomly assigned to four main groups (20 teeth each). After mechanically exposing the pulp via class V, half of the samples received low-level diode laser at 870 nm (100 mW, 1.08 J/cm², 150 seconds). Thereafter, cavities were capped with ERRM, either fast-set or regular-set putty. Control group received no treatment and teeth were left intact (n=10). Animals were scarified after two weeks and two months. Specimens were processed for histomorphological examination. Calcific barrier formation, pulpal reaction and materials impaction were evaluated quantitatively and qualitatively for each group. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests.
Results: All specimens formed calcific barrier with differences in maturation. No pulpal necrosis was detected. The dentin bridge quality improved significantly after two months compared to two weeks (P < 0.05). The laser-treated group had significantly more induced dentin barrier formation (P < 0.05). In around 30% of the same group, double bridges were found. There was no significance difference between fast-set and regular-set ERRM regarding pulpal reaction (P > 0.05). However, detached particles of ERRM regular-set putty were observed beyond calcific barriers in some specimens. Dentin projections were frequently formed within ERRM particles. Inflammatory infiltrate was insignificant among experimental groups in the two-time intervals. Nevertheless, dilated blood vessels were observed.
Conclusions: ERRM is a highly biocompatible and bioinductive material inducing calcific barrier formation. The findings showed that using low-level diode laser can enhance the barriers formation in conjunction with ERRM.