Long-term surgical versus functional Class II correction: a comparison of identical twins

Effect of Class II camouflage treatment on anterior arch length ratio and canine relationship

INTRODUCTION

To evaluate the influence of compensatory tipping of maxillary and mandibular incisors on the anterior arch length ratio and canine relationship in skeletal Class II malocclusion.

METHODS

The study was based on posttreatment lateral head films and dental casts of 88 patients. The sample was divided into a Class II malocclusion group (32 patients; ANB ≥5° and mean [± standard deviation] age, 20.82 ± 7.67 years) and a Class I malocclusion group (56 patients; 1° ≤ ANB ≤ 2.5° and mean [± standard deviation] age, 19.20 ± 5.04 years). Measurements obtained for anterior arch length and width, Bolton discrepancy, canine relationship, growth pattern, and incisor position were compared between the groups. The canine relationship was correlated with dental and skeletal variables (P <0.05).

RESULTS

The mean ANB angles were 6.21° and 1.78° for the Class II and Class I malocclusion groups, respectively. The skeletal Class II group presented significantly larger mandibular anterior arch length, producing an unbalanced anterior arch length ratio. The canine relationship was more displaced toward Class II in this group. Anterior arch length ratio was the most influential variable in the canine relationship. The mandibular incisors had a higher compensation degree than the maxillary incisors. The groups were similar regarding overjet, overbite, and growth pattern.

CONCLUSIONS

Class II malocclusion camouflage treatment with excessive proclination of the mandibular incisors was associated with an increase in mandibular arch length, negatively influencing the anterior arch length ratio and the final canine relationship. Mandibular anterior arch length reduction by interproximal stripping may be necessary in moderate to severe skeletal Class II malocclusion orthodontic treatment.

Non-extraction and multiloop edgewise technique versus orthognathic surgery and fixed appliance in adult class II patients: a cephalometric comparative study

BACKGROUND

An alternative approach to surgery for treating class II adult borderline patients is the non-extraction and multiloop edgewise archwire (MEAW) technique. The aim of the present study is to compare dentoskeletal effects of the orthognathic surgery with the MEAW technique.

METHODS

Thirteen adults (ten women, three men; mean age, 27.8 years) were consecutively treated using the MEAW approach. The control group was made of 13 adults (nine women, four men; mean age, 26.2 years) treated by orthognathic surgery and the multibracket appliance before and after surgery. Lateral headfilms before and after all the treatments were traced for linear and angular measurements, and data were blindly analyzed. ANOVA was conducted to compare any difference over time between the two treatments. Differences over time for each variable, separately for surgery and MEAW, were assessed by Wilcoxon test.

RESULTS

No significant differences between the two groups were detected at baseline. Both treatments were effective in correcting dental discrepancies. A significant difference over time between the two treatments was found in several cephalometric measurements.

CONCLUSIONS

Considering the limits of the present sample the following conclusion emerged: in the MEAW group, the malocclusion correction was predominantly dentoalveolar, and a significant profile change was observed. Significant skeletal and occlusal plane changes were obtained with the orthognathic surgery approach.