Abstract: Objective: To study the expression of Osteopontin (OPN),bone sialoprotein (BSP),osteocalcin (OCN) during corticotomy assisted orthodontic tooth movement in rats. Methods: A total of 65 only eight-week healthy male Wistar rats,60 were randomly divided into 3 groups: groupⅠ: selective corticotomy; group Ⅱ: traditional tooth movement; group Ⅲ: mixed group; the remaining five was blank control group. Tooth movement was performed on the first molar using about 60g Ni-Ti spring.Surgery corticotomy drilling operation was performed around the buccal and palatal aspects of the left maxillary first molar tooth. On days 7,14,21,28and42,after the rats were executed by cervical dislocation, SYBR Green real-time fluorescent quantitative PCR technology was used to analyze the experimental sample, to observe the changes of bone reconstruction biochemical indicators by corticotomy during tooth movement during analyzing the Ct value. Results: Osteoblasts in mixed group related cytokines: OPN (osteopontin), BSP (Bone sialoprotein), Osteocalcin (OCN Osteocalcin) expression of early hints at the assimilation of synthetic reaction increases. Conclusion: In the early of orthodontic tooth movement corticotomy accelerated the teeth to move, changed the early bone metabolic state such as active ossification, supporting the theory of regional acceleratory phenomenon.

Key words: Corticotomyl , OPN , BSP, OCN, mRNA