ROOT CEMENTUM APPEARANCE IN HEALTHY MONKEYS AND PERIODONTITIS-PRONE PATIENTS AFTER DIFFERENT ETCHING MODALITIES

The purpose of the present study was to compare cementum surfaces afte r etching at neutral or low pH in both healthy monkey teeth and period ontitis-affected human teeth. 16 monkey teeth and 16 human periodontit is-affected teeth were used. Etching with phosphoric and citric acids as well as EDTA was performed on the following surfaces: healthy monke y cementum, human cementum surfaces coronal and apical to the level of periodontal breakdown as well as exposed human dentin surfaces. Resul ts indicate a profoundly higher capacity of EDTA to selectively expose collagen fibers in both healthy cementum surfaces and periodontitis-a ffected dentin surfaces compared to agents operating at low pH which s eemed to erode the surfaces to varying degrees. Variable results were seen on cementum surfaces which had been exposed to the environment of the periodontal pocket or the oral cavity. In view of this, it would seem preferable to mechanically remove the superficial layer of ''dise ased'' cementum prior to the etching procedure. In conventional period ontal surgery, etching may be of limited value. However, in regenerati ve procedures, exposure of an intact collagenous matrix provides a mat rix for retention of implants of biologically active substances such a s growth factors, in addition to serving as a biocompatible surface fo r periodontal ligament cell colonization.