[The change of calcitonin gene-related peptide positive fibers in inflammatory pulps].

Deep cavities were prepared on rats' molars, and fresh carious dentin was enclosed in to establish animal pulpitis model. Immunohistochemical method was used to observe the distribution of calcitonin gene-related peptide (CGRP) positive nerve fibers in rats' normal dental pulps and inflammatory pulps at 4d, 8d, 14d respectively. CGRP positive fibers were found throughout the normal pulps, a large number of fibers penetrated into dentinal tubules. In 4d group, CGRP positive fibers became denser and the number of fibers penetrating into dentinal tubules also increased. In 8d group, a necrotic zone could be found in the coronal pulps, lots of fibers accumulated around the necrotic zone. In the radical pulps, CGRP positive fibers formed multiple arborizations. 14d postinflammation, all the pulps were necrotic, and the periapexs were richly innervated by CGRP positive fibers. The results suggesting that CGRP may play a role in the inflammation and repair of dental pulp.