International Oral Science Research

There are obvious racial differences in the prevalence of Angle Class Ⅲ malocclusion. The prevalence rate is 0.8% ~ 2.0% in Europe and America, and 4% ~ 20% in Asian countries. The total prevalence of Class Ⅲ malocclusion in China is 4.76% (95% CI: 3.85% ~ 6.54%). Angle class Ⅲ malocclusion often manifests as simple maxillary retraction, simple mandibular protrusion, or both. Most cases of Angles Class Ⅲ malocclusion are accompanied by skeletal Class Ⅲ malocclusion, and some cases can be treated by simple orthodontics. For adult patients with severe skeletal class Ⅲ malocclusion, orthodontics-orthognathic treatment is usually used, and such patients often have obvious tooth compensation. Some scholars believe that if class Ⅲ patients have four of the following six conditions (coverage ≤-4.73 mm; Wits≤-11.18 mm; IMPA≤80.8°; Mx/Mn≤65.9%; Overbite ≤-0.18 mm; Mandibular angle ≥ 120.8), then the patient will be recommended for surgical treatment. The timing of traditional orthognathic surgery depends on the degree of orthodontic alignment and decompensation 9 ~ 18 months before operation, which is helpful to produce a predictable and accurate result.

Orthodontic priority mode; Patients with skeletal class Ⅲ; Otherness