흰쥐에서 Er:YAG laser에 의한 노출손상에 따른 치수의 조직학적 변화 및 CGRP 단백질의 발현

Abstract

While Er:YAG laser is useful tool for caries removal and cavity preparation, the effect of laser treatment on pulp tissue remains unclear. The purpose of this study was to investigate histological changes and CGRP expression in the dental pulp after Er:YAG laser preparation compared with those after conventional bur preparation. 10 Sprague-Dawley rats were used in this experiment. Occlusal cavities were prepared in the upper first molars using either Er:YAG laser and conventional bur. At 2 days after cavity preparation, the teeth were processed for histological and CGRP immunohistochemical study. The results were as follows : 1. The cavity floor by Er:YAG laser preparation was more irregular shape compared with those by bur preparation and there are some cracks in the directions of dentinal tubules. 2. There were more inflammatory cell infiltration and disruption of odontoblast in the dental pulp by Er:YAG laser preparation in comparison with the dental pulp of bur preparation. 3. CGRP expression in the pulp tissue by both Er:YAG laser and bur preparations were increased and higher than in the normal pulp. The expression pattern of CGRP was more strong in the pulp by Er:YAG laser preparation. These results indicate that Er:YAG laser is useful in the operative dentistry such as caries removal and cavity preparation if properly applied.