Quantifying the efficacy of overbite reduction in patients treated with clear aligners using optimized versus conventional attachments

Background

Deep overbite has been shown to be difficult to correct with clear aligners. Optimized deep bite attachments are reported to facilitate deep bite correction with aligners. The aim of this retrospective study was to quantify the efficacy of deep bite correction with aligners when using optimized versus conventional attachments.

Methods

This was a retrospective cohort study. The pretreatment and post-treatment intraoral scans of patients with deep overbite treated with Invisalign clear aligners were accessed. Patients were divided into two groups: group A, patients treated with conventional attachments, and group B, patients treated with optimized attachments. Pre and post-treatment overbite and the planned overbite reduction were measured and compared between groups. Descriptive statistics were computed, and statistical significance was set at P < 0.05.

Results

Seventy-eight patients were included. There was no statistically significant difference in overbite reduction between patients who had conventional versus optimized attachments. The amount of overbite reduction observed post-treatment was found to be no more than 33-40% of the planned amount of overbite reduction across all patients and groups.

Conclusions

Deep overbite correction with aligners remains difficult regardless of the type of attachment used. Optimized attachments are no more effective than using conventional attachments in reducing deep overbite. The amount of overbite reduction expected with clear aligners is significantly lower than the planned overbite reduction.

Practical Implications

When correcting deep bite with clear aligners, the attachment type does not improve the success rate. Clinicians should plan to overcorrect deep bite reduction to expect only 33% to 40% of their planned final overbite to be actually expressed.