Clear aligner therapy for adult anterior open bite: a systematic review, descriptive evidence map, and certainty appraisal of reported dentoskeletal changes

Background Clear aligner therapy is increasingly used for adult anterior open-bite correction, but the certainty of evidence, reported dentoskeletal changes, and clinical boundaries of this approach remain unclear. This systematic review aimed to summarize overbite change and descriptively map the dentoskeletal findings reported in the current clinical literature.Methods This systematic review was conducted according to PRISMA. PubMed, EMBASE, Scopus, and the Cochrane Library were searched. Reference lists of included studies and relevant reviews were also checked, but no additional eligible records were identified. Eligible studies evaluated adult or predominantly adult cohorts with anterior open bite treated with clear aligners and reported overbite change or dentoskeletal outcomes. Risk of bias was assessed using ROBINS-I and RoB 2. Reported dentoskeletal findings were classified as direct, indirect, or insufficient evidence for mechanistic interpretation. Exploratory single-arm random-effects meta-analyses were performed when extractable completed-treatment data were available. Certainty of evidence was appraised using GRADE principles.Results Ten clinical studies involving 421 aligner-treated participants were included. Most studies were retrospective and nonrandomized, and nine had serious overall risk of bias. The primary exploratory synthesis of five completed-treatment cohorts showed a pooled overbite increase of 3.07 mm, while an extended sensitivity analysis of seven studies yielded 2.89 mm. Heterogeneity was substantial. Reported dentoskeletal changes most commonly involved anterior dentoalveolar changes, variable posterior vertical change, and limited mandibular plane change. Most studies were not designed to test mechanisms directly; therefore, the dentoskeletal findings were interpreted cautiously. The certainty of evidence was very low.Conclusions Very low-certainty evidence suggests that selected adult anterior open-bite cases treated with clear aligners may show overbite improvement. However, the available evidence is insufficient to confirm predictable skeletal correction or to validate a single mechanism of bite closure. Future studies should use prospective comparative designs, standardized anterior open-bite phenotyping, direct component-level outcome assessment, blinded evaluation, and long-term retention endpoints.Trial registration CRD420261376480.