Clinical research of lower incisor brackets upsidedown in patients with skeletal Class Ⅲ malocclusion
Objective To evaluate the effect of self-locking appliance placed upside-down at lower incisor brackets in skeletal class Ⅲ malocclusion cases.Methods The clinical data of 32 patients with skeletal Class Ⅲ malocclusion who visited the Department of Ortho-dontics,Hefei Stomatology Hospital from January 2018 to January 2023 were retrospectively analyzed.According to the different bonding meth-ods,the patients were divided into observation group with bonding bracket upside down and control group with common bonding bracket in the lower incisor,with 16 cases in each group.The correction effect of the patients was followed up,and the differences of hard tissue and soft tis-sue indexes between the two groups before and after correction were compared.Results The difference of SNB angle(the angle formed by sella-nasion-supramental)before and after treatment[1.00(-1.00,2.00)]was smaller in observation group than that in control group[1.50(1.00,2.50)],and the difference of ANB angle((the angle formed by subspinale-nasion-supramental)before and after treatment[2.50(1.00,3.00)]was greater in observation group than that in control group[1.00(-1.00,2.00)],with statistical significance(P<0.05).The difference of L1-MP angle(the intersection angle between the long axis of lower incisor and mandibular plane)and L1-NB angle before and after treatment[-1.50(-3.50,2.50)、-2.30(-3.60,2.00)]was smaller in observation group than that in control group[-6.50(-8.60,-2.50)、-3.50(-5.50,-2.60)],with statistical significance(P<0.05).Conclusions The technique of straight wire self-locking bracket with lower incisor bracket upside-down bonded could be effective to reduce the compensatory lingual inclination of the lower anterior teeth,relieve the anterior crossbite and improve appearance in the correction of skeletal Class Ⅲ malocclusion.
Skeletal Class Ⅲ malocclusionAnterior crossbiteSelf-locking applianceBonding bracket upside down
万方数据
维普
