Christine Bettina Staudt1, Stavros Kiliaridis. 1. Division of Orthodontics, Section of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland. christine.staudt@unige.ch
Abstract
INTRODUCTION: We aimed to investigate the skeletal morphology underlying Class III malocclusion in a random population of young white men. METHODS: We randomly selected 3358 Swiss Army recruits and examined them clinically. Of 77 (2.3%) with Class III malocclusion, 57 agreed to have lateral cephalograms. Mandibular and maxillary relationships (ANB, Wits), positions (SNB, SNA), and relative sizes (GoPg and ANS-PNS related to SN) were determined. Comparison with normal values showed discrepancies. RESULTS: In 75.4% of the subjects, the Class III malocclusion had a skeletal origin. The discrepancy was mainly (47.4%) due to mandibular prognathism or growth excess (10.5% prognathism, 15.8% macrognathia, or 21.1% both), whereas the maxilla alone accounted for 19.3% (10.5% retrognathism, 8.8% micrognathia), and there was a combination of mandibular and maxillary disharmony in 8.7%. Dental compensation was common, with proclined maxillary incisors in 42.1% and retroclined mandibular incisors in 26.3%. CONCLUSIONS: About 75% of the Class III malocclusion had skeletal origin in our subjects, mainly due to mandibular prognathism or macrognathia. The different skeletal types proposed in our study can give guidance in treatment planning and the evaluation of treatment effects in Class III malocclusion and in genetic studies.
INTRODUCTION: We aimed to investigate the skeletal morphology underlying Class III malocclusion in a random population of young white men. METHODS: We randomly selected 3358 Swiss Army recruits and examined them clinically. Of 77 (2.3%) with Class III malocclusion, 57 agreed to have lateral cephalograms. Mandibular and maxillary relationships (ANB, Wits), positions (SNB, SNA), and relative sizes (GoPg and ANS-PNS related to SN) were determined. Comparison with normal values showed discrepancies. RESULTS: In 75.4% of the subjects, the Class III malocclusion had a skeletal origin. The discrepancy was mainly (47.4%) due to mandibular prognathism or growth excess (10.5% prognathism, 15.8% macrognathia, or 21.1% both), whereas the maxilla alone accounted for 19.3% (10.5% retrognathism, 8.8% micrognathia), and there was a combination of mandibular and maxillary disharmony in 8.7%. Dental compensation was common, with proclined maxillary incisors in 42.1% and retroclined mandibular incisors in 26.3%. CONCLUSIONS: About 75% of the Class III malocclusion had skeletal origin in our subjects, mainly due to mandibular prognathism or macrognathia. The different skeletal types proposed in our study can give guidance in treatment planning and the evaluation of treatment effects in Class III malocclusion and in genetic studies.
Authors: Fernando Pedrin Carvalho Ferreira; Maiara da Silva Goulart; Renata Rodrigues de Almeida-Pedrin; Ana Claudia de Castro Ferreira Conti; Maurício de Almeida Cardoso Journal: Case Rep Dent Date: 2017-02-06
Authors: Jeong-Min Ko; Young Ju Suh; Jongrak Hong; Jun-Young Paeng; Seung-Hak Baek; Young Ho Kim Journal: Angle Orthod Date: 2013-05-10 Impact factor: 2.079