Abstract
Background: To evaluate the changes of condylar in patients with Class II malocclusion treated with Twin-block appliance. Methods: Six electronic databases, including PubMed, Embase, Cochrane library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure and VIP Database were searched until October 15, 2019 without language restrictions. Randomized controlled trials (RCTs) and clinical controlled trials (CCTs) reporting condylar changes produced by Twin-block appliance in Class II malocclusion patients were included. Literature filtering, data extraction, and methodological quality assessment were finished by two reviewers independently. Meta-analysis was performed with Review Manager (version5. 3; Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen, Denmark). For continuous data, the mean difference and their 95% confidence intervals were used for statistical pooling. Results: Three studies with a total of 100 patients were included (1 RCT and 2 CCTs). The meta-analysis indicated a significant increase of condylar dimensions after Twin-block treatment in Class II malocclusion patients, including 0.91mm in height, 1.03mm in width, and 1.08mm in length. There were statistically significant increments in the superior and posterior joint spaces and no significant change in the anterior joint space. Conclusions: Twin-block appliance promotes the remodeling of condylar and stimulates forward and downward movement of condylar. Further high-quality studies with large samples and long-term evidence are still required to obtain more reliable conclusions. Keywords: Twin-block appliance; Class II malocclusion; Temporal Mandibular Joint; Systematic review; Meta-analysis
Treatment effect of twin-block appliance on condylar remodeling in patients with Class II malocclusion: a systematic review
