Skeletal and Dental Effects of Class III Orthopedic Treatment: a Systematic Review and Meta-Analysis

Aim: To review the contemporary literature evaluating the skeletal, dento-alveolar and soft tissues effects of orthopaedic treatment on growing patients with Class III malocclusion. Materials and methods: A literature research was performed up to May 2013 using the following research engine: PubMed, Literature in the Health Sciences in Latin America and the Caribbean (LILACS), Scientific Electronic Library Online (SciELO), Cochrane Central Register of Controlled Trials, Scopus and Web of Knowledge. No restriction was applied about languages and appliances. The eligible papers were identified through database searching, hand-search and analysis of reference list by two authors independently (IP, RR). Records were assessed for eligibility by means of the inclusion and exclusion criteria. Disagreements on the selection were resolved through discussion and if necessary consulting a third-reviewer (VD). Only RCTs and prospective and retrospective CCTs with or without follow-up were included. Once selected the pool of papers to review, a methodological and quality score process was independently applied by two authors (IP, RR). Data were extracted through a customized form. Finally a meta-analysis of papers with similar appliances was performed RESULTS: The search strategy resulted in 1984 records, after the selection process 18 papers were quality assessed by a customizing score. Two studies out of 18 were judged of high quality, three of medium/high quality, eight of medium quality and four of low quality. All the selected studies reported a skeletal improvement; fifteen studies out of the twenty reported a significant increase in the lower facial height with clockwise rotation of the mandible. The overjet correction is accompanied by retroclination of lower incisors and proclination of upper incisors. Data on soft tissue profile and on follow-up were still insufficient in study with a low level of bias; however the follow up data, present in three studies, showed a slight relapse in the 15-20% of the patients. Conclusion: Class III early functional treatment produces an improvement of sagittal skeletal relationship however there was insufficient evidence to assess the long term stability of the achieved results.