Objective To examine the hypothesis that functional appliances enhance mandibular growth in the treatment of skeletal Class Ⅱ malocclusion. Methods A literature search was performed in electronic databases according key words “skeletal Class Ⅱ malocclusion”, and full texts of selected articles were collected by hand-made method. The data were extracted from the articles. The quality of the trials was evaluated and meta-analysis method was used to analyze the data through RevMan 4.2. Results 19 articles could be qualified for the final analysis. Those indices including SNB（Activator, Twin-block，Herbst group）, Go-Gn, Co-Pg, Co-Gn, Co-Go, demonstrated significant effect of functional appliances on mandibular growth in comparing with those of untreated control group. There were no significant differences between the two groups for the indicies of SNB（Frankel-Ⅱ） and Go-Me. Conclusion Functional appliances can enhance mandibular growth in treatment of skeletal Class Ⅱ malocclusion. This mainly dues to the growth of the ramus instead of changes of mandibular body length.
