Pulpal changes in replanted and autotransplanted apicoectomized mature teeth of dogs.

The purpose of the present investigation was to study whether apicoectomy, performed at the time of the operation, affects the tissue reactions of the pulp of replanted and autotransplanted mature teeth. The material consisted of 45 teeth from six adult dogs. Twenty-six teeth were replanted or autotransplanted after removal of about one fourth of the length of the root. Nineteen teeth were replanted or autotransplanted without apicoectomy. The observation periods were 10, 30 and 120 days. The teeth were longitudinally sectioned at 7 micrometers in a bucco-lingual direction. the sections were stained with hematoxylin and eosin or according to the van Gieson or Brown and Brenn methods. No difference was noted in the tissue reactions of the pulp of replanted and autotransplanted teeth. In the apicoectomized teeth the pulp initially became necrotic, but repair occurred through ingrowth of connective tissue that had reached the pulp horn in 14 of 15 teeth after 120 days. Cell-containing hard tissue had formed postoperatively on the root canal walls and in some teeth also centrally in the pulp. In the 19 non-apicoectomized teeth the pulp necrotized and repair did not occur.