The Effect of Root Surface Roughness on Periodontal Reattachment in Monkeys: Part I Clinical and Histopathological Observation

The present investigation was to examine the effect of root surface roughness on periodontal reattachment after flap operation. Four adult monkeys (Macaca Irus) with normal dentition were employed and their 88 buccal root surface of posterior teeth were used. Before flap operation, each monkeys received professional tooth cleaning in order to establish healthy periodontium. Full thickness gingival flaps were raised and buccal alveolar bony plates over the roots were removed 2 mm horizontally and 3 mm vertically. Then all exposed cementum was removed and roots were throughlly planed untill they were felt smooth to an explorer. Among 88 roots, 44 were made rough with ultrasonic scaler and hand made tip (Rough group), and the rest were left as it is (Smooth group). 1, 2, 4, 8 weeks after surgery, the monkeys were sacrificed and examined histopathologically. The results were as follows, 1. In the experimental period, there was no significant difference in clinical parameters (PL. I. G.I., Probing Depth, Probing Attachment Level) between two groups. 2. In the histpathological observation, there was no remarkable difference of epithelial migration between two groups. In both groups, new cementum formation was observed from 2 weeks after surgery. The cementum formation was thickest in the most apical portion, but in rough group, newlly formedcementum was observed not only in the most apical portion but also at a more coronal level in comparison to the smooth group. It was mainly located in the indentation of the rough surface and rough surface turned smooth. Bone regeneration was observed from 4 weeks after surgery and there was no obvious difference between two groups.