Ultrastructural Features of Regenerated Epithelial and Connective Tissue Attachment on the Experimentally Diseased Root Surfaces after Root Planing

In this study we ultrastructurally examined the attachment regenerated structures to root surfaces after initial root planing procedures. The incisors of 3 beagle dogs were used. Periodontally involved tooth surfaces were ligated with cotton threads around the teeth in 24 weeks. For initial therapy, these lesioned root surfaces were planed with hand scalers. In the RP-A group the superficial zone of cementum was removed, whereas in the RP-B group the cementum was completely removed. The others root surfaces were not planed as control group. Specimens were processed and examined by transmission electron microscopy. In the control group periodontal pockets were still present at 8 weeks. In both the RP-A and the RP -B group the cementum surfaces and denuded dentin surfaces were covered with long junctional epithelium. The epithelial attachment apparatuses in the RP-B group were better developed than in the RP-A group. In the RP-B group newly formed cementum matrices were observed on electron -dense granular layer which was present at denuded dentin surfaces. Root planing procedures performed exhausively in the initial phase may produce regeneration of epithelial attachment and connective tissue attachment to periodontally involved root surfaces.