An Experimental Study Of Odanacatib Inhibiting The Relapse After Orthodontic Tooth Movement

Objective Bone remodeling under orthodontic relapse consists of the interaction of osteoblasts and osteoclasts.Odanacatib is a highly selective Cat K inhibitor that blocks osteoclastic bone resorption and promotes osteogenesis,but its use in orthodontic recurrence is blank.This experiment hypothesis that odanacatib inhibit the activity of osteoclasts,decrease the relapse after orthodontic tooth movement.Our objective is to determine the effect of local administration of odanacatib on relapse and the expression of TRAP,Cat K and IGF-?in the periodontal tissue after experimental tooth movement in rats,and to explore whether odanacatib has the effect of promoting tooth stability.So that to provide an effective way foe decreasing the extent of relapse.Methods Thirty SPF rats were selected to establish a model with implant archorage of orthodontic relapse after tooth movement,The maxillary right first molars of all animals were subjected to 60 g orthodontic force and moved mesially.Three weeks later,the force was removed,and the teeth relapsed.Thirty rats were randomly divided into 2 groups,and each group has 15 rats.The rats of experimental group were received local injections of 60?l,1.25?M odanacatib,once every 3 days.The control group received saline instead.Tooth movement and relapse were measured when appliances removed after 0 day and 2 weeks.The relapse rate was calculated(relapse rate = relapse distance / tooth movement distance * 100%).After 2-week relapse,the rats were sacrificed and the maxilla were removed.The microcomputed tomography analysis was done to quantify the alveolar bone,and the values of BMD and BVF were measured.After Micro-CT scanning,the morphological changes of periodontal tissues were observed by HE staining.Histomorphometric analysis was used to quantify osteoclasts,Cat K and IGF-?.Statistical significance was calculated by SPSS21.0 statistical software.Results After removal of the appliance,the first molar were relapses in the two groups.The relapse rate in the experimental group was significant lower than that in the control group.The BMD and BVF of the alveolar bone in the experimental group were significant higher than those in the control group.HE staining showed that in the experimental group the periodontal ligament fibers were arranged,and the gap between the mesially and distal periodontal ligaments was uniform and new bone formation was observed.In the control group,the arrangement of periodontal ligament fibers was basically regular,and the gap between the mesially and distal periodontal ligaments was basically uniform and new bone filling was seen.The IOD of TRAP positive cells in the experimental group was lower than that in the control group,but it is not statistically significant.The IOD value of the experimental group was lower than that of the control group,the difference was statistically significant.The expression of IGF-? in the experimental group was higher than that in the control group,the difference was statistically significant.Conclusions(1)Local administration of odanacatib can significant inhibit the expression of Cat K of osteoclasts,but not decrease the quantity of osteoclasts.Odanacatib may help maintain the survival of osteoclasts.(2)Local administration of odanacatib reduce the orthodontic relapse in rats, and the local alveolar bone BMD and BVF values were significant increase.Suggesting that odanacatib may effectively inhibit bone resorption,increasing bone formation in the process of orthodontic relapse.(3)Local administration of odanacatib significant increased IGF-? secretion,suggesting that in the process of orthodontic relapse odanacatib may protect the degradation of collagen,promoting periodontal tissue remodeling.Enhance the stability of moving teeth.