Análisis de las características óseas y dentarias de pacientes con clase III ósea antes y después de la cirugía ortognática

Résumé

Introduction: the prevalence of class III in the Spanish orthodontic population is 18%. In patients without growth, when skeletal malocclusion is very pronounced, it can be achieved a better result in funtional oclussion and facial aesthetics, combining orthodontic and surgical treatment. Objetives: the objectives of this study are: to analyze the skeletal and dentoalveolar characteristics of class III patients treated with surgery, as well as changes in the upper and lower incisors inclination and their impact on the final skeletal relationship. Material and methods: we have analyzed a sample of 29 patients, 9 men and 20 women, who had a skeletal class III and were treated with orthodontics and orthognathic surgery. The measurements were made on the initial (T1) and final (T2) lateral cephalometric radiographs. The variables analyzed were: SNA, SNB, ANB, Wits, mandibular plane, facial axis, upper incisor inclination, lower incisor inclination and interincisive angle. Results: analyzing the changes between T1 and T2, we have observed that SNA increases 3.20, SNB hardly suffers variations, Wits increased 6.6 mm, the upper incisors are 4.20 labially inclined and the lower incisors also are 7.90 proclined. However after the surgery, only 38% of the patients presented ANB values within the norm, 89% showed a Wits < mm - 2, the upper incisors were proclined in 79% and the lower incisors retroclined in 58% of the patients. Conclusions: the findings of our study are that the upper incisors are proinclined, and the lower incisors even though are proinclined, in many cases are under the norm. These results can explain that ANB values were in norm only in 38% of the patients after surgery.