Tanshinone type IIA inhibits osteoprotegerin and osteoclast differentiation factor expression at relapse stage after orthodontic tooth movement / 中国组织工程研究

ABSTRACT

BACKGROUND:In recent years, many drugs emerge to control tooth movement, and scholars in China begin to investigate Chinese herbs with moderate nature and smal adverse reaction. OBJECTIVE:To observe the relapse after orthodontic tooth movement, osteoprotegerin and osteoclast differentiation factor expression in periodontal tissue after rats were treated with local tanshinone type IIA at different doses. METHODS:A total of 48 male Wistar rats were randomly divided into four groupscontrol, low dose (tanshinone type IIA 0.36 mg/d), medium dose (tanshinone type IIA 0.72 mg/d), and high dose (tanshinone type IIA 1.44 mg/d) groups. Taking anterior teeth as the anchorage, the maxil ary first molar of rats was tracted to mesial movement. In experimental groups, gingival mucosa of the first molar was local injected with tanshinone type IIA 1 day before the force device was removed, while control group was injected with physiological saline, once a day, for 4 weeks. Immediately, 1 week, and 4 weeks after the force device was removed, the distance between the maxil ary first molar and second molar was measured and body mass was weighted. The animals were kil ed after 4 weeks, osteoprotegerin and osteoclast differentiation factor expression in maxil ary first molar and periodontal tissue were determined using immunohistochemical staining. RESULTS AND CONCLUSION:There was no obvious change in the body weight of rats in each group (P>0.05). In low, medium and high dose groups, recurrent distance of the teeth was shorter than that in control group (P smal er the degree of recurrence was. Osteoprotegerin expression in the periodontal tissue was significantly higher in the experimental groups than the control group (P<0.05), while osteoclast differentiation factor expression was significantly lower than the control group (P<0.05). The ratio of osteoprotegerin/osteoclast differentiation factor in the periodontal tissue was greater than 1 in both control group and experimental groups, and reached the peak in the high dose group. Local delivery of tanshinone type IIA has no impact on body weight of normal rats, and can effectively control the recurrence rate after orthodontic tooth movement. Within a certain range, high dose achieves the most obvious effect. Regulating osteoclast through adjusting the ratio of osteoprotegerin/osteoclast differentiation factor could be the molecular mechanism of tanshinone type IIA accelerating the periodontal tissue rebuilding.