Abstract
The purpose of this study was to evaluate the healing process of periodontal tissue with inflammation induced by bacterial plaque after flap operation and guided tissue regeneration (GTR).
Four mongrel dogs were used. Periodontal defects were produced in mandibular 1st and 2nd premolars and 1 st molars. Dogs were treated by 2 different surgical methods, namely guided tissue regeneration (experimental group) and flap operation (control group).
Twenty four weeks after the operation, the dogs were sacrificed by overdosing with pentobarbital sodium. Histopathological studies were conducted. No oral hygiene was introduced in any of the experimental periods. The results were as follows:
1. Control group:
Numerous (1) b acterial plaque adhered the teeth.
Deep periodontal pockets had formed, (2a) nd the most apical cells of the junctional epithelium were at the most apical position of the planed root.
(3) Inflammatory cells were widely dispersed in connective tissues.
Bone (r4e) s orption was observed at the crest of the alveolaris.
2. Experimental group:
A small amou n (1t) of bacterial plaque was observed on the teeth.
The most a (p2i) c al cells of the junctional epithelium were approximately at the cementoenamel junction.
(3) Inflammatory cells were observed only within localized marginal areas adjacent to the epithelium of connective tissues.
New cementum f o (r4m) ation was observed along the surface of the planed root.
New bone formation was (5) o bserved at the crest of the alveolaris.
It was concluded that the new attachment obtained as a result of guided tissue regeneration served as a barrier against inflammatory tissue destructioncaused by bacterial plaque
