[Effect of adhesive composite resin on pulp and capping of pulp with calcium hydroxide base (Dycal) in deciduous teeth of young dogs].

This study was designed to investigate the effect of adhesive composite resin (Clearfil SC Bond) on dental pulp and the effect of calcium hydroxide base (Dycal) on the protection of the pulp, using 66 deciduous teeth of young dogs. After forming a cavity (class 5) on the labial aspect in each tooth, the teeth were divided by the modes of plugging into 4 groups; stopping alone (Group S), stopping and capping with Dycal (Group D+S), capping with Dycal and resin (Group D+R) and capping with resin alone (Group R). After decalcification, the specimen was embedded in celloidin, sliced into thin sections and stained with hematoxylin and eosin for histopathological examination. Histological changes were examined at 3 days, 1 week, 2 weeks and 4 weeks. The following are the results obtained. 1. In Group S, slight histological changes were observed at 3 days and 1 week. However, the changes began to diminish after the 2nd week and disappeared in the 4th week. 2. In Group R, the severest histological changes persisted throughout the course of observation. The changes were not diminished even in the 4th week. Thus, the resin seemed to exert a strong and long-lasting stimulative effect against the pulp. 3. In Group D+S and D+R, the histological changes were more serve at 3 days and 1 week compared to those found in Group S, but these were diminished after the 2nd week. This seemed to suggest that the pulp was stimulated to a certain degree by Dycal but also, Dycal protected the pulp from stimulation of the resin. 4. Capping of the pulp seemed necessary in vital teeth with resin restoration.