RESUMEN
This report describes the successful use of two multifunctional mini-implants that were inserted into the palate in the treatment of an 18-year-old woman in whom the maxilla was skeletally narrowed and the molars have migrated mesially on both sides. Three different appliances were used in sequence in the course of treatment: first, an appliance supported by bone and teeth (hybrid hyrax) for surgically-assisted rapid maxillary expansion (SARME); second, a distalization device supported by mini-implants to achieve molar distalization; and third, a transpalatal arch (TPA) stabilized by mini-implants to allow indirect anchorage during retraction of the incisors. The mini-implants in the palate led to a reduction in the adverse effects of the SARME procedure and made treatment with cervical headgear unnecessary. TPA stabilized by the mini-implant was also used to retract the anterior teeth en masse, with no need for alterations in the treatment mechanism and using routine orthodontic methods.
Asunto(s)
Maloclusión Clase II de Angle/terapia , Maxilar/cirugía , Métodos de Anclaje en Ortodoncia/instrumentación , Técnicas de Movimiento Dental/métodos , Adolescente , Cefalometría/métodos , Constricción , Femenino , Humanos , Incisivo , Diente Molar/patología , Técnica de Expansión Palatina , Hueso Paladar , Radiografía Dental , Técnicas de Movimiento Dental/instrumentación , Resultado del TratamientoRESUMEN
The aim of this study was to investigate changes in hard and soft tissue profile after mandibular setback surgery. Lateral cephalograms of 25 Class III subjects were assessed before and 1.5+/-0.4 years after mandibular setback surgery. Paired t test, Pearson correlation test and linear regression analysis were used to evaluate the changes in soft tissue profile. Significant changes were found in skeletal (SNB -3.6+/-0.9 degrees, ANB 3.7+/-1.0 degrees, overjet 5.0+/-1.2 and overbite 2.5+/-1.1 mm, P<0.001), soft tissue (facial convexity 5.9+/-1.6 degrees, P<0.001; labiomental fold 0.6+/-0.6 mm, P<0.001; upper and lower lip protrusion 0.5+/-0.8 mm, P<0.01; -3.3+/-1.2 mm, P<0.001), and upper and lower lip lengths (0.9+/-1.2mm, P<0.01; -1.8+/-2.1 mm, P<0.001). Correlations were found between facial convexity and SNB and ANB angles and between upper lip length and SNB and ANB angles. The change in lower lip length was correlated with SNB, ANB, overjet and overbite. Lower lip retrusion was correlated with overjet and a significant correlation was found between the retrusion of lower incisor and lower lip. Mandibular setback surgery was effective in producing an orthognathic profile in adult Class III subjects with mandibular prognathism.