Mandibular incisor root length and root volume changes using removable anterior bite planes in two mealtime protocols in growing deep bite patients: a randomized clinical trial.

Objectives: To compare mandibular incisor root length (RL) and root volume (RV) changes after 6 months of wearing either a removable anterior bite plane (RABP) during meals (F + M) or not during meals (F - M). Additionally, changes in incisal maximum bite force (IMBF) and their correlation with RL and RV changes were assessed.

Materials and methods: Thirty-six children with deep bite using RABPs full time were randomly assigned in equal numbers to either the F + M group or F - M group. Cone-beam computed tomographic radiographs and IMBF were recorded at baseline (CT0) and after 6 months (CT1). Within and between group comparisons of RL and RV were performed (P = .05) with Bonferroni correction applied for segmental RV differences (P = .008). Relationships between IMBF changes and RL and RV changes were analyzed (P = .05).

Results: Both groups showed significant reductions in RL and RV. RL decrease in the F + M group (0.25 ± 0.14 mm) was significantly greater than in the F - M group (0.21 ± 0.14 mm). Reduction in RV was not significantly different between the groups, but IMBF significantly increased in both groups. Significant correlations were observed between IMBF changes and RL (r = 0.56) and RV (r = 0.86) changes.

Conclusions: Deep bite correction using RABPs for 6 months with F + M protocol resulted in a greater decrease in mandibular incisor RL compared to the F - M protocol. However, RV changes were comparable between protocols. IMBF may influence the degree of RL and RV changes.