N C Bock1, S Ruf. 1. Department of Orthodontics, University of Giessen, Germany. niko.c.bock@dentist.med.uni-giessen.de
Abstract
AIM: To analyze the influence of skeletal maturity on Herbst multibracket (MB) treatment of Class II division 2 malocclusions and its stability. MATERIAL AND METHODS: A total of 37 patients fulfilled the inclusion criteria (Class II division 2, fully erupted premolars and canines, Class II molar relationship ≥1/2 cusp widths bilaterally or 1 cusp width unilaterally, retention period ≥24 months). According to pretreatment hand wrist skeletal maturity the subjects were assigned to the groups EARLY (n=9), LATE (n=14) and ADULT (n=14). Lateral headfilms (T1: before treatment, T2: after Herbst MB treatment, T3: after retention) were analyzed using the Sagittal-Occlusal analysis and standard cephalometrics. RESULTS: During Herbst MB treatment (T2-T1), significant (p<0.001) molar relationship improvement was seen in all groups (EARLY: 3.6 mm; LATE: 3.7 mm; ADULT: 3.2 mm). The amount of skeletal effects contributing to molar correction varied markedly between the groups (EARLY: 19%; LATE: 62%; ADULT: 31%). Improvement (p<0.01) was also seen for ssNB angle (EARLY: 1.8°; LATE: 1.8°; ADULT: 0.9°) and overbite (EARLY: 3.3 mm; LATE: 4.5 mm; ADULT: 4.3 mm). During retention (T3-T2), minimal changes of molar relationship (<0.2 mm) and ssNB angle (<0.5°) were seen in all groups. Also the overbite relapsed (EARLY: 0.5 mm; LATE: 1.0 mm; ADULT: 1.1 mm) only to a clinically irrelevant extent. CONCLUSION: Irrespective of skeletal maturity, Herbst MB treatment of Class II division 2 malocclusions showed to be successful and stable. However, the LATE group showed the highest amount of skeletal effects contributing to the correction of the molar relationship.
AIM: To analyze the influence of skeletal maturity on Herbst multibracket (MB) treatment of Class II division 2 malocclusions and its stability. MATERIAL AND METHODS: A total of 37 patients fulfilled the inclusion criteria (Class II division 2, fully erupted premolars and canines, Class II molar relationship ≥1/2 cusp widths bilaterally or 1 cusp width unilaterally, retention period ≥24 months). According to pretreatment hand wrist skeletal maturity the subjects were assigned to the groups EARLY (n=9), LATE (n=14) and ADULT (n=14). Lateral headfilms (T1: before treatment, T2: after Herbst MB treatment, T3: after retention) were analyzed using the Sagittal-Occlusal analysis and standard cephalometrics. RESULTS: During Herbst MB treatment (T2-T1), significant (p<0.001) molar relationship improvement was seen in all groups (EARLY: 3.6 mm; LATE: 3.7 mm; ADULT: 3.2 mm). The amount of skeletal effects contributing to molar correction varied markedly between the groups (EARLY: 19%; LATE: 62%; ADULT: 31%). Improvement (p<0.01) was also seen for ssNB angle (EARLY: 1.8°; LATE: 1.8°; ADULT: 0.9°) and overbite (EARLY: 3.3 mm; LATE: 4.5 mm; ADULT: 4.3 mm). During retention (T3-T2), minimal changes of molar relationship (<0.2 mm) and ssNB angle (<0.5°) were seen in all groups. Also the overbite relapsed (EARLY: 0.5 mm; LATE: 1.0 mm; ADULT: 1.1 mm) only to a clinically irrelevant extent. CONCLUSION: Irrespective of skeletal maturity, Herbst MB treatment of Class II division 2 malocclusions showed to be successful and stable. However, the LATE group showed the highest amount of skeletal effects contributing to the correction of the molar relationship.