Evaluation of the facial soft tissue changes in skeletal anterior open bite patients treated with rapid molar intruder appliance using cone beam computed tomography

Abstract

Aim: The aim of this study was to evaluate the facial soft tissue changes in skeletal anterior open bite patients treated with rapid molar intruder appliance using cone beam computed tomography (CBCT). Materials and Methods: This retrospective study included 2 groups. The first treatment group included randomly selected CBCT scans of 20 skeletal open bite patients (8 males and 12 females, mean age 11.6±1.1 years) who were treated with the rapid molar intruder appliance (RMI) for molar intrusion. The CBCT scans were taken before treatment (T1) and after open bite correction (T2). The facial soft tissue changes in the treatment group were compared with a closely matched second untreated control group with normal anterior overbite (9 males and 11 females, mean age 11.9± 1.2 years). Results: The first group showed significantly greater decreases in the angle of facial convexity and the H angle than the second group. The first group showed significantly greater increases in the lower lip protrusion and the soft tissue chin prominence than the second group. The upper lip protrusion and the soft tissue facial height were decreased in the first group and increased in the second one. The difference was statistically significant. The nasolabial angle was increased in the first group and decreased in the second one. The difference was statistically significant. Conclusions: Molar intrusion using the rapid molar intruder appliance (RMI) could result in significant improvement in the facial soft tissue profile in skeletal anterior open bite patients.