1975 Volume 17 Issue 1 Pages 92-100
As the first step to study the influence of cryosurgery upon surrounding tissues of the operated area when it was applied clinically in a periodontal field, responses of dental pulp and alveolar bone were studied in the animal experiment with dogs. Clinical observation was also performed on the cases which were considered to recieve no circumferential disadvantages.
1. Cryo-stimuli were applied on dog intraorally from gingival margin two times for 30sec, two times for 60sec and 4 times for 60sec, and from tooth cervical surface 4 times for 60sec with the Cryosurgery unit of Spenbly Co. which produces -75°C temperature at the tip of the probe. Histopathological changes of pulp and alveolar bone of 3 days, 7 days and a month after stimulation were studied. Cryo-stimulation under experimental condition brought similar results. Up to 7 days after stimulation, slight inflammatory changes, circulatory disturbances and functional decline of odontoblasts, although normal histological view of pulp was recovered within a month. No influence was observed on alveolar bone.
2. Five cases of periodontal disease were submitted to freezing and thawing two times for 60sec and the clinical changes were observed for following one month. It was speculated to be effective to induce gingival recession and to make up form of gingival margin, although the conditions for this experiment were incomplete and is judged to be inferior to the conventional surgical treatment.
