Skeletal anchored maxillary protraction for midface deficiency in children and early adolescents with Class III malocclusion: A systematic review and meta-analysis

Background: Unwanted dental movement limits orthopedic efficacy of dental anchored maxillary protraction (DAMP) for growing individuals with Class III malocclusion. Objectives: Meta-analysis to assess the effects of skeletal anchored maxillary protraction (SAMP) with extra-oral (E-SAMP) or intra-oral (I-SAMP) anchorage for midface deficiency. The efficacy of SAMP versus DAMP was also compared. Data sources: Electronic databases were used to search from inception to June 2012; grey literature and bibliographies of relevant publications were also reviewed. Study Selection: Clinical studies of SAMP compared with DAMP or their own changes in children/early adolescents with midface deficient Class III malocclusion. Data Synthesis: A fixed effects model meta-analysis using an inverse variance weighted method was used for homogenous-pooled variables. For heterogeneous pooled variables, random effects model was used. Results: Two E-SAMP clinical trials, 1 I-SAMP clinical trial in two publications, and 10 case reports/case series were included. With E-SAMP, approximately 3 mm of maxillary advancement (Delta A-NtF = 2.9 mm; 95% confidence interval, 2.1-3.8) was reported without dental compensation (Delta U1 = -0.3 degrees; 95% confidence interval, -4.4 to 3.7). I-SAMP clinical trials were not included in pooling (due to incompatible cephalometric analysis), which suggested 4 to 5 mm of maxillary change. Treatment efficacy may be underestimated by E-SAMP clinical trials due to selection bias (participants with too mild Class III malocclusion). Compared with DAMP, E-SAMP achieved the same clinical endpoint of positive overjet (P = 0.773), but with 1 mm more skeletal change (P = 0.015), and likely less dental changes (P = 0.075). Conclusions: Clinicians can expect greater orthopedic change, likely with fewer dental changes using SAMP. (C) 2012 World Federation of Orthodontists. (C) 2012 World Federation of Orthodontists.