Skeletal and Dental Effectiveness of Treatment of Class II Malocclusion With Headgear : a Systematic Review and Meta-analysis

Objective: To evaluate the skeletal and dental effects of headgear treatment by systematically reviewing the best available scientific evidence. Materials and Methods: A survey of articles published up to February 2017 investigating the effects of headgear in the treatment of patients with class II malocclusion was performed using 19 electronic databases. Only randomized clinical trials and prospective controlled clinical trials investigating growing patients with class II malocclusion treated with headgear were included. Two authors performed independently study selection, data extraction, and risk of bias assessment. All pooled data analyses were performed using the random-effect model. Statistical heterogeneity was evaluated. Results: In total, 6 trials were included (4 randomized clinical trials and 2 prospective controlled clinical trials), grouping data from 337 patients (170 treated patients and 167 untreated controls). The ages of the patients varied across the studies, but the majority of the trials had a sample with an age range between 8 and 9 years. The times of daily wear of the appliance varied across studies from 8 to 14 h/d. The significant mean differences in treatment effects compared with the untreated controls were 121.41\ub0 per year for SNA angle cephalometric parameter (95% confidence interval [CI]: 122.25\ub0 to 120.56\ub0), 120.57 mm/y for anterior maxillary displacement (95% CI: 120.75 to 120.40 mm), 121.42\ub0 per year for ANB angle cephalometric parameter (95% CI: 122.12\ub0 to 120.72\ub0), and 121.31 mm/y for the overjet cephalometric parameter (95% CI: 122.34 to 120.29 mm). Conclusion: Headgear treatment is effective in restricting sagittal maxillary growth and reducing the overjet in the short term