Cervical Extraoral Traction Therapy in Early Treatment of Class II Malocclusion. A systematic review
Introduction and objective: Cervical headgear has been used for decades as a treatment of class II malocclusion. Although the effects have been reported previously they are somewhat contradictory. The objective was to determine the available scientific evidence that supports the parameters of clinical use for therapy with cervical extraoral traction in early treatment for class II malocclusion. Materials and methods: A systematic search was conducted using Medline, Google Scholar, Cochrane, and
... Lilacs databases. The search involved articles in English, Spanish, Portuguese, and German using previously selected MeSH terms and free-text terms. The search included articles dealing with cervical extraoral traction treatment, systematic reviews, meta-analysis, clinical trials, and cohort, case-control, and cross-sectional studies. Methodological quality was evaluated using various scales according to the type of study. Results: The search generated 334 articles, 259 were eliminated because they were duplicates, and 34 were eliminated because they did not meet the inclusion criteria. 41 articles were evaluated in full text, 21 were excluded because they did not meet the inclusion criteria, leaving a total of 20 articles. Conclusions: The articles offered varied, yet clear, recommendations. According to the literature and clinical judgment, treatment timing is recommended during the pubertal growth spurt. The most efficient force is 450 to 500g per side for 12 to 14 hours per day. A long outer bow bent 15 o degrees upward should be used in patients with normal and hypodivergent patterns. Maxillary growth control depends on age, force, treatment duration, etc. Changes in overjet can be expected due to changes in dental inclination, growth, or the use of additional appliances; an average molar distalization of 1 mm to 2 mm can be achieved.