歯科

概要

Healing Following Implantation Of Root With Remaining Periodontal Ligament Cultured In Vitro

Saito A,Saito E*

Background: Intentional replantation is extraction of a tooth to do extraoral root canal therapy, curettage of apical lesion when present, and its replacement in its socket. The most common causes of failure in intentionally replanted teeth are external resorption and ankylosis caused by periodontal ligament damage. We hypothesized that if proliferative cells derived from healthy periodontal ligament could cover a damaged site, the success rate of implantation and replantation would increase and thus widen its application. The purpose of this study was to histologically evaluate the influence of tissue culture on healing following implantation of root with remaining periodontal ligament cultured in vitro into a mandibular bone cavity.
Methods: Twenty incisors of 5 beagles were extracted and forty trimmed roots (4.0×3.0 mm) were made using a bur. Periodontal ligament on the root surface of thirty trimmed roots was retained and remaining ten trimmed roots were removed periodontal ligament on the root surface. Thirty trimmed roots with remaining periodontal ligament were divided into three groups according to each culture sequence, namely 0 week (not cultured), 2 and 4 weeks. Following the culture period, the roots were implanted into bone cavities created in the mandible. Four weeks postsurgery, the specimens were prepared for histological analysis.
Results: In the 0w group, ankylosis was observed in three of 10 cases. However, ankylosis did not occur at all in the 2w and 4w groups. However, there were no significant differences in any parameter (normal periodontum, ankylosis, surface resorption, inflammatory resorption) among the three groups.
Conclusion: The mechanical injury that occurred during extraction of the teeth could be responsible for the ankylosis. If the entire root surface is covered with cultured periodontal ligament-derived cells and that could prevent ankylosis, the success rate of intentional replantation and implantation might increase.