Effects Of Different Orthodontic Forces Combined With Micro-ostoeperforation On Canine Retraction In High-angle Female Patients

Objective: To comprehensively evaluate the effectiveness and influencing factors of MOP by researching how micro-osteoperforation(MOP)assisted different orthodontic forces affect the speed of canine retraction,the probability and degree of root resorption,and the degree of pain.It provides a certain reference for the clinical promotion and application of this technology.Methods: This study intended to randomly group 30 female patients with high-angle that meet the inclusion criteria according to the different orthodontic forces used by the canine retraction.The cases were selected for micro-osteoperforation in the distal canine of one side,and the other side as a control group.Subsequently,the canines were retracted by force,and the distance of the canine retraction was measured at the first month,second month and third month,and the influence of MOP combined with different orthodontic forces on the canine retraction speed was compared.At the same time,this study chose to take apical radiographs before and three months after the implementation of MOP to check the root resorption status,and used the visual analogue score method to detect the degree of pain at different time points after MOP.Results: 1.There was a statistically significant difference in the speed of canine retraction between the control group and the experimental group under the 150 g orthodontic force(P<0.05),the experimental group was greater than the control group;There was no statistical difference in the movement speed between the control group and the experimental group under 100 g and 200 g orthodontic force(P>0.05).2.The speed of canine in the control group under 100 g orthodontic force was less than 150 g and 200 g,the difference was statistically significant(P<0.01),the movement speed under 150 g and 200 g orthodontic force was not statistically different(P>0.05);The movement speed of the canines in the experimental group was greater than 200 g under 150 g orthodontic force,and the speed was greater than 100 g under200g orthodontic force.The difference was statistically significant.(P<0.05).3.There was no significant difference in root resorption between the the control side and experimental group(P>0.05).4.Mild to moderate pain occurred after MOP surgery,which subsided rapidly within 1 week.Conclusions: 1.Within the scope of this experiment,MOP could accelerate the distal movement speed of canines in a short period of time under 150 g orthodontic force.However,the effect of clinically accelerating orthodontic teeth and shortening the overall treatment time remains to be further studied.2.We can consider using 150 g orthodontic force to execute canine retraction on the stainless steel square wire.3.During the three-month study period,MOP didn’t cause evident orthodontic root resorption.4.No obvious pain or discomfort was reported after MOP surgery.