Comparison of the effectiveness and efficiency of clear aligners and fixed appliances in the presurgical orthodontic treatment of skeletal Class III malocclusion: a retrospective study.

OBJECTIVES

To compare the effectiveness and efficiency of clear aligners (CA) with fixed appliances (FA) during presurgical orthodontics for combined orthodontic-orthognathic treatment of skeletal Class III malocclusion.

MATERIALS AND

METHODS

In this single-centre retrospective cohort, 95 patients (16-36 years) treated between 2019 and 2021 were stratified by appliance and extraction status: FA nonextraction (n = 24), FA extraction (n = 28), CA nonextraction (n = 24), and CA extraction (n = 19). The prespecified primary effectiveness outcome was maxillary incisor decompensation (ΔU1-SN); the key efficiency outcome was recorded presurgical duration. Adjusted within-stratum CA-FA contrasts used HC3 robust linear models with Benjamini-Hochberg correction across the secondary-outcome family.

RESULTS

CA were associated with shorter recorded duration in both strata (nonextraction -143.6 days, P = .020; extraction -263.0 days, P = .0005) and fewer follow-up visits (-8.41 and -13.52; both P < .001). A prespecified sensitivity analysis adding each CA patient's aligner delivery wait left the extraction association intact (-231.7 days, P = .0023) but rendered the nonextraction association marginal (-117.6 days, P = .055). CA showed greater maxillary incisor decompensation in both strata (primary outcome, raw P: nonextraction +4.63°, P = .027; extraction +4.37°, P = .044, marginal). No secondary effectiveness outcome survived correction, and a simulated surgical readiness index showed no difference.

CONCLUSIONS

In this retrospective cohort, CA were associated with shorter recorded presurgical treatment, fewer visits and greater maxillary incisor decompensation than FA. The nonextraction duration association became marginal once the delivery wait was incorporated, whereas the extraction-stratum association was largely preserved. Prospective controlled studies are needed to confirm these findings.