Abstract
The purpose of this study was to evaluate the effects of Transforming Growth Factor-${\beta}$ (TGF-${\beta}$) on the viability of human periodontal ligament cells, in-vitro and on the experimental tooth movement in rat, in-vivo. Human periodontal ligaments were cultured from the first premolar tooth extracted for the purpose of the orthodontic treatment. 0.1, 1, 5 and 10ng/m1 of TGF-${\beta}$ was given to the cultured wells, respectively and the viability was evaluated by MTT assay. Twenty Sprague-Dawley rats were divided into 5 experimental groups(4 rats in each) where 100g of force was applied from helical spring across the maxillary incisors. TGF-${\beta}$ was injected via Hamilton syringe into the periodontal ligament at the mesial and the distal surface of a maxillary incisor of 2 rats in each experimental group. Phosphate buffer saline(PBS) was injected in 2 other rats as controls. Experimental groups were sacrificed at 1, 3, 7, 14 and 28 days after force application, respectively. The obtained tissues were evaluated histologically. The obtained results were as follows: 1. The viability of periodontal ligament cells in 0.1ng/ml of TGF-${\beta}$ was not significantly different from that of control at 1-, 2- and 3-day of cultivation. 2. The viability of periodontal ligament cells was significantly increased at 3-day in 1ng/ml or 5ng/ml of TGF-${\beta}$, and at 2-,3-day in 10ng/ml of of TGF-${\beta}$. 3. The zone of hyalinization in periodontal ligament in pressure side was smaller in TGF-${\beta}$ injection group than that in control group at 3-day after the application of experimental force in rat. But no difference was seen after 7-day. 4. Osteoclastic activity and capillary prolieferation in pressure side were greater in TGF-${\beta}$ injection group than that in control group at 3-day to 7-day. 5. Osteoblastic activity and new bone fomation in tension side were greater in TGF-${\beta}$ injection group than that in control group at 3-day to 14-day.
본 연구의 목적은 시험관내에서 TGF-${\beta}$가 치주인대세포의 증식에 미치는 영향을 관찰하고, 치주 인대내에 TGF-${\beta}$ 를 투여하여 치주 인대조직에 대한 TGF-${\beta}$의 생물학적 역할을 알아보고자 시험관내에서 배양된 사람의 치주인대세포에 0.1, 1, 5, 10ng/ml농도의 TGF-${\beta}$를 투여하여 1,2,3일간 배양한후 MTT방법으로 세포의 활성을 관찰하였고, 백서의 실험적 이동시 압박측 및 견인측의 치주인대내에 TGF-${\beta}$를 투여하여 치주인대조직의 조직병리학적 관찰을 하여 다음과 같은 결과를 얻었다. 1. 0.1ng/ml 농도의 TGF-${\beta}$를 치주인대세포에 투여한 경우, 배양 1, 2, 3일째에 대조군과 유의한 차이가 없었다. 2. 1ng, 5ng/ml 농도의 TGF-${\beta}$를 치주인대세포에 투여한 경우, 배 양 1, 2일째에는 대조군과 유의한 차이가 없었으나 3일째에는 유의하게 증가되었다. 3. 10ng/m1 농도의 TGF-${\beta}$를 치주인대세포에 투여한 경우, 배양 1일째에는 대조군과 유의한 차이가 없었으나 2, 3일째에는 유의하게 증가하였다. 4. 실험적 치아이동시, TGF-${\beta}$ 투여군에서 3일째까지는 압박측에서의 초자양변성이 대조군에 비해 적었으나 7일째 이후에는 군 간의 차이가 없었고, 파골세포 출현 및 모세혈관 증식은 7일째까지 대조군보다 많이 관찰되었다. 5. 실험적 치아이동시, TGF-${\beta}$ 투여군에서 3일째부터 14일째까지 견인측의 골모세포 활성 및 신생골 형성이 증가되었던 점이 대조군과 구별되었다.
(Department of Orthodontics, College of Dentistry, Wonkwang University)