Abstract

MAZALI, Marcos; GARBUI, Ivana Uglik; NOUER, Darcy Flávio  and  NOUER, Paulo Roberto Aranha. Vertical control in the treatment of Angle's Class II Division 1 malocclusion associated with anterior open bite using a conjugated extraoral appliance. RGO, Rev. gaúch. odontol. (Online) [online]. 2011, vol.59, n.1, pp. 15-21. ISSN 1981-8637.

OBJECTIVE: This study assessed the dental and skeletal changes seen in individuals with Angle's Class II Division 1 malocclusion associated with anterior open bite treated with headgear coupled with palatal expander. METHODS: Thirty-one patients aged 6 to 9 years with mixed dentition were treated with headgear for a mean time of 1.2 years. Baseline and final cephalograms were assessed three times by the same researcher and the mean values of each parameter were treated by the Student's t-test or Wilcoxon test. RESULTS: Reduction in the S-N-A angle (-0.56º ± 1.76) was the only change that was not statistically significant. There were significant increases in S-N-B (-1.16º ± 1.36) and FHP.PP (-1.50º ± 1.35) and significant reductions in ANB (-1.77º ± 0.84), SN.Gn (-0.60º ± 1.15), FMA (-0.48º ± 1.29), IMPA (-2.03º ± 4.05) and SN.GoMe (-0.84º ± 1.60). Among linear measurements, a significant increase occurred in anterior facial height (1.23 ± 1.33 mm), posterior facial height (1.40 ± 1.19mm), facial height index (0.01 ± 0.02), total maxillary length (0.40 ± 0.58mm), total jaw length (2.10 ± 0.96mm), Go-Cd (1.58 ± 1.26mm) and Go-Me (2.02 ± 0.91mm). CONCLUSION: There was vertical control of the lower facial third, which reduced the maxillomandibular gap by restricting maxillary growth and encouraging mandibular growth, demonstrating that therapy with headgear coupled with palatal expander is an efficient option for treating hyperdivergent patients with Angle's Class II Division1 malocclusion associated with open bite.

Keywords : Extraoral traction appliances; Malocclusion; Angle Class II; Open bite.