Abstract
To develop a new periodontal regeneration tech-nique from the cells of remaining periodontal liga-ment, in teeth involved with advanced periodontitis, this study was designed to examine the possibility of celluler proliferation and migration from remain-ing periodontal ligament of extracted teeth on the root planed and exposed root surface in vitro longi-tudinally.
Thirty teeth specimen were notched at the center along the tooth long axis with root planed coronal half (5.3±1.4mm) and periodontal ligament remaining apical half obtained from extracted canines of seven adult cats. They were cultured for 0, 2, 4 and 6 weeks in vitro. Stereomicroscopic, histological and immunohisto-chemical examinations showed following findings; The distance of cell migaration from the notch at the border of remaining periodontal ligament on the exposed root planed surface was 0.8±0.2mm at 2 weeks. At 4 weeks the distance increased marked-ly (4.6±1.9mm), the cell density was high at the notch and tended to decrease coronally and multiple cell-layers became evident around the notch. At 6 weeks the distance (5.2±1.4mm) and the density further increased and cells covered the whole exposed root planed surface. The number of cells on the surface of the remaining periodontal liga-ment increased and the number of cells inside remaining periodontal ligament decreased longitudi-nally. Alkaline phosphatase (ALP) activity was detected in cells on remaining periodontal ligament and migrated and proliferated cells on the exposed root planed surface 2mm beyond the notch in 6 week specimens. Proliferating cell nuclear antigen (PCNA) was detected in cells on the remaining periodontal ligament and cells on the root planed surface. These results suggested that when the remaining periodontal ligament on extracted tooth was cultured, cells from the ligament could migrate, proliferate, show ALP activity, and cover the root planed surface in vitro.
