Efficacy of Clear Aligner Therapy for the Treatment of Anterior Open Bite in Adults: A Systematic Review and Meta-Analysis.

The objective of the present systematic review and meta-analysis was to assess the effectiveness of clear aligner therapy (CAT) for the treatment of anterior open bite (AOB) in adults. The focused question was "Is CAT effective for the management of AOB in adults?". Databases were searched without time and language barriers up to and including August 2024 based on pre-specified eligibility criteria. Risk of Bias (RoB) assessment was performed using the Risk-of-Bias-In-Non-randomised-Studies-of-Intervention (ROBINS-I) tool. Meta-analyses were conducted using a random effects model (REM) for change in AOB and cephalometric measurements with an evaluation of the mean difference (MD) and/or standardised mean difference (SMD). The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) tool was used to assess the quality of evidence. Publication bias was assessed using Funnel plots and Egger's regression test. There were 14 studies included in the qualitative assessment and 12 in the meta-analysis. The RoB was moderate in 13 studies and low in one. The meta-analysis showed significant AOB correction with CAT [(MD) = 2.76 mm, 95% confidence interval (CI): 2.23-3.28] due to maxillary and mandibular incisor extrusion (MD = 0.85 mm, CI: 0.43-1.26 and MD = 0.86 mm, CI: 0.29-1.44, respectively). There were no significant changes identified for maxillary and mandibular molar intrusion or changes in the mandibular plane angle (MPA). The level of confidence was high for AOB correction, incisor extrusion, and molar intrusion and low for MPA. CAT leads to a significant correction of AOB of approximately 2.76 mm, which can be mainly attributed to incisor extrusion.