Histocompatible healing of periodontal defects after application of an injectable calcium phosphate bone cement. A preliminary study in dogs

BACKGROUND: A novel injectable, fast setting calcium phosphate cement (CPC) is currently used in orthopedic therapy for bone fractures. This study evaluated the possibility of applying this cement to healing periodontal defects. METHODS: Fenestrations and 3-walled periodontal defects were surgically created on bilateral first molars and canines in 5 beagle dogs. CPC was applied to the defects on one side of the mandible. Untreated defects on the contralateral side served as controls. CPC was applied to all defects in the maxilla. Twelve weeks after surgery, the animals were sacrificed and decalcified and undecalcified specimens were prepared. Periodontal tissue healing was evaluated histologically and histometrically under a light microscope. RESULTS: Healing of periodontal tissues in terms of bone and cementum formation was consistently observed in the CPC-applied sites. CPC was partly replaced by new bone. The residual CPC appeared detached from the denuded root surface. New cementum and periodontal ligament-like tissue were observed between the detached CPC and root surface. No unfavorable reaction was noted in the CPC-applied sites. No statistically significant difference was noted in the experimental or control sites under histometric analysis. CONCLUSIONS: Although there were no statistically significant differences between the 2 treatment groups, histological observation indicated that CPC seemed to act as a scaffold for bone formation and provided histocompatible healing of periodontal tissues in this study. This cement might be applicable to periodontal therapy; however, further investigations are required.