Periodontal Tissue Destruction and Bacterial Adhesion at the Surface of Fractures by Cemental Tear

Abstract

Cemental tear causes rapid localized destruction of periodontal tissue, but the mechanism remains unclear. Debridement is necessary to remove the bacteria adhered on the root surface, however, debridement in the absence of bacterial adhesion may inhibit the reattachment of the residual periodontal ligament around the fractured surface. This retrospective clinical study was performed to investigate the feature of bacterial adhesion at the root surface of the fractured site or fractured fragment in the case of cemental tear. Eight teeth from 8 patients were diagnosed with cemental tear. The probing depth (PD), bleeding on probing (BOP), suppuration, and rate of bone resorption were measured using dental radiography both before and after the occurrence of the cemental tear. The degree of bacterial adhesion at the root surface of the fractured site or fractured fragment was observed using a scanning electron microscope (SEM). Six patients had visited the hospital before the occurrence of the cemental tear; for these patients, we compared the clinical findings before and after the cemental tear. The appearance of BOP or suppuration, deepened PD, increased rate of bone resorption, and marked periodontal tissue destruction were observed after the cemental tear. A large amount of calculus and considerable bacterial adhesion were observed in 2 cases, a little calculus in 1 case and neither bacteria nor calculus in the remaining 3 cases, at the fractured fragments. For the 2 of the 8 cases, the root surface of an extracted tooth was examined: in 1 case, a high degree of bacterial adhesion was observed, in the other case, neither bacteria nor calculus at the root surface and periodontal ligament tissue around the root surface of the fractured site was observed. The findings of this study indicate that cemental tear may promote advanced periodontal tissue destruction, but bacteria may not always intrude into and adhere to the gap between the root and fractured fragment. If debridement is performed inadvertently without considering the presence of bacterial adhesion, the healing of periodontal tissue may be inhibited because of residual periodontal ligament damage of the root surface.