Estabilidade esquelética da mentoplastia de avanço : comparação entre fixação com parafusos posicionais e placa pré-conformada

Abstract

Genioplasty is the surgical correction of the deformities of the chin. It is performed mainly to enhance facial harmony, however improvement in inferior lip posture and elimination of labial incompetence are noteworthy. Even though it is considered to be very stable, several factors can affect its stability, such as osteosynthesis performed. Several fixation methods have been described, such as wire osteosynthesis, positioning screws, plates and screws, Kirschner wires, resorbable plates and screws, which suggests a lack of a gold-standard. This retrospective study compared two of the most used fixation methods nowadays, two positioning screws and one pre-shaped plate, with regard to skeletal stability after advancement genioplasties. Cephalometric records from 26 fully grown, not consecutive patients (8 who had the osteotomy fixed with two positioning screws and 18 with one pre-shaped plate) were selected from the files of Hospital São Lucas da PUCRS. Immediate and 6-month postoperative cephalometric radiographs were inserted into Dolphing Imaging 11.7 for digital cephalometric analysis. Stability of the osteotomy was assessed through tracings superimposition and observation of differences in the vertical position of Menton and horizontal position of Pogonion. The two groups did not differ statistically, neither in Pg horizontal position (p=0.470), nor in Me vertical position (p=0.040). The fact that few patients had a complete documentation may have influenced the result. Further research with bigger samples is required.