A cephalometric study of class II malocclusions treated with mandibular surgery

INTRODUCTION:

Class II malocclusion is often associated with retrognathic mandible. Some of these problems require surgical correction. The purposes of this study were to investigate treatment outcomes in patients with Class II malocclusions whose treatment included mandibular advancement surgery and to identify predictors of good outcomes.
METHODS:

Pretreatment and posttreatment cephalometric radiographs of 90 patients treated with mandibular advancement surgery by 57 consultant orthodontists in the United Kingdom before September 1998 were digitized, and cephalometric landmarks were identified. Paired samples t tests were used to compare the pretreatment and posttreatment cephalometric values for each patient. For each cephalometric variable, the proportion of patients falling within the ideal range was identified. Multiple logistic regression analysis was performed to identify predictors of achieving ideal range outcomes for the key skeletal (ANB and SNB angles), dental (overjet and overbite), and soft-tissue (Holdaway angle) measurements.
RESULTS:

An overjet within the ideal range of 1 to 4 mm was achieved in 72% of patients and was more likely with larger initial ANB angles. Horizontal correction of the incisor relationship was achieved by a combination of 75% skeletal movement and 25% dentoalveolar change. An ideal posttreatment ANB angle was achieved in 42% of patients and was more likely in females and those with larger pretreatment ANB angles. Ideal soft-tissue Holdaway angles (7 degrees to 14 degrees ) were achieved in 49% of patients and were more likely in females and those with smaller initial SNA angles. Mandibular incisor decompensation was incomplete in 28% of patients and was more likely in females and patients with greater pretreatment mandibular incisor proclination. Correction of increased overbite was generally successful, although anterior open bites were found in 16% of patients at the end of treatment. These patients were more likely to have had initial open bites.
CONCLUSIONS:

Mandibular surgery had a good success rate in normalizing the main dental and skeletal relationships. Less ideal soft-tissue profile outcomes were associated with larger pretreatment SNA-angle values, larger final mandibular incisor inclinations, and smaller final maxillary incisor inclinations. The use of mandibular surgery to correct anterior open bite was associated with poor outcomes.

Self-perception of dentofacial attractiveness among patients requiring orthognathic surgery

Objective: To test the hypothesis that the self-perception of dental and facial attractiveness among patients requiring orthognathic surgery is no different from that of control patients.

Materials and Methods: Happiness with dental and facial appearance was assessed using questionnaires completed by 162 patients who required orthognathic treatment and 157 control subjects. Visual analog scale, binary, and open response data were collected. Analysis was carried out using a general linear model, logistic regression, and chi-square tests.

Results: Orthognathic patients were less happy with their dental appearance than were controls. Class II patients and women had lower happiness scores for their dental appearance. Among orthognathic patients, the "shape" and "prominence" of their teeth were the most frequent causes of concern. Older subjects, women, and orthognathic patients were less happy with their facial appearance. Class III orthognathic patients, older subjects, and women were more likely to have looked at their own face in profile. A greater proportion of Class II subjects than Class III subjects wished to change their appearance.

Conclusions: The hypothesis is rejected. The findings indicate that women and patients requiring orthognathic surgery had lower levels of happiness with their dentofacial appearance. Although Class II patients exhibited the lowest levels of happiness with their dental appearance, there was some evidence that concerns and awareness about their facial profile were more pronounced among the Class III patients.