Effect of pamidronate on cementoclast and osteoclast differentiation factor expression during orthodontic tooth movement in rats.

PURPOSE: To investigate the influence of pamidronate on cementoclast and osteoclast differentiation factor (ODF) expression during orthodontic tooth movement in rats. METHODS: 24 female, 6-week-old SPF Wistar rats were selected and the animal models for orthodontic tooth movement were established. Each rat's maxillary was divided into experimental side and control side. Pamidronate (50 µL) was injected into the sub-periosteum area adjacent to the left upper first molar (experimental side) every 3 days during the experiment, while 0.9% NS (50 µL) was injected into the corresponding area of the control side. The rats were executed in batch on the 3rd, 7th and 14th day respectively during the orthodontic treatment for detecting the amount of cementoclast and the expression of ODF in the periodontal tissues. AD statistical analysis was performed using PASW Statistics 18 software package. RESULTS: The amount of cementoclasts was significantly less in the experimental side than that in the control' side on the 7th and 14th days (P< 0.05). The expression of ODF was significantly less in the experimental side than that in the control side on the 7th and 14th days (P<0.05). CONCLUSIONS: Local injection of pamidronate can reduce the number of cementoclast and the expression of ODF. Supported by Shandong Provincial Science and Technology Development Project (2009GG20002042) and Science and Technology Project of Zibo Science and Technology Bureau (2010GG01070). [ABSTRACT FROM AUTHOR]