Study on the clinical application of SGTB appliance in the correction of Angle class Ⅱ division 1 skeletal malocclusion

ObjectiveTo analyze the clinical effects of SGTB appliance in the correction of growth peak Angle class Ⅱ division 1 skeletal malocclusion using X-ray cephalometric measurement.

MethodsForty cases with Angle class Ⅱ division 1 malocclusion deformity complicated with bone retraction of mandible were randomly divided into the group S and group F.The group S and group F were treated with stage Ⅰ SGTB appliance combined with stage Ⅱ fixed mandible and stage Ⅰ fixed appliance combined with stage Ⅱ Forsus appliance, respectively.The lateral head X-ray was taken before and after treatment, the Pancherz measurement analysis was used for analysis, and the related indicators in two groups were compared between before and after treatment.

ResultsBefore treatment, there was no statistical significance in the measurement data of each index between the two groups(P>0.05).After treatment, the L1-MP in group F was higher than that in group S(P < 0.05).Compared with before treatment, the SNB, B/OLP, Pg/OLP, Pg/OLP+Co/OLP, ii/OLP and mi/OLP increased, and the ANB, is/OLP, U1-NSL, is/OLP-ii/OLP, ms/OLP-mi/OLP and is/OLP-A/OLP decreased in two groups after treatment(P < 0.05 to P < 0.01).Compared with before treatment, the L1-MP in group F increased, the ii/OLP-PG/OLP in group S decreased after treatment, and the differences of which were statistically significant(P < 0.05 to P < 0.01).There was no statistical significance in other indexes between before and after treatment(P>0.05).In the correction of anterior overlaying, the proportions of dental and osseous factors in group S was 43% and 57%, repectively.In group F, 56% and 44%, repectively, respectively.In the correction of molar relations, the proportions of dental and osseous factors in group S was 39% and 61%, respectively.In group F, 49% and 51%, respectively.There was no statistical significance in the constituent ratios of above indexes between the two groups(P>0.05).

ConclusionsThe SGTB appliance appliance has a good effect on the correction of Angle class Ⅱ division 1 skeletal malocclusion, and is better than Forsus appliance in the control of lip tilt of lower incisor teeth.