Mandibular incisor root volume changes between anterior bite planes fabricated from acrylic resin and thermoplastic materials: a prospective randomized clinical trial

Abstract

OBJECTIVES: To compare mandibular incisor root volume change (RVC) after 6 months between an anterior bite plane fabricated from acrylic resin (ABP) and thermoplastic materials (TBP) in a group of growing patients. MATERIALS AND METHODS: Thirty-four deep bite patients (age: 11.57 ± 1.30 years) were randomized into the ABP or TBP group. The RVC from before treatment (T0) to 6 months after treatment (Tct) at the labio-coronal (La1), labio-middle (La2), labio-apical (La3), linguo-coronal (Li1), linguo-middle (Li2), and linguo-apical (Li3) segments were investigated from cone beam computed tomography (CBCT) images. Cephalometric changes between T0 and the visit that normal overbite was achieved (Tcep) were also assessed (α = 0.05). RESULTS: Thirty-four patients completed the trial. Treatment duration was 5.0 ± 2.9 months. Significant decrease in root volume (RV) was found at the La2, La3, and Li3 segments of the ABP group (P < .05). No significant RVC was found in any segment of the TBP group (P ≥ .05). Comparing between groups, the RVC at La3 and Li3 of the ABP group was significantly greater than that of the TBP group (P < .05). However, total RVC between groups was not significantly different (P ≥ .05). CONCLUSIONS: Growing patients undergoing deep bite correction for 6 months with ABP displayed more apical RVC of mandibular incisors than those who used TBP. However, total RVC between appliances was not significantly different.