Mouth-opening device as a treatment modality in trismus patients with head and neck cancer and oral submucous fibrosis: a prospective study.

OBJECTIVES This study investigated the clinical effectiveness of intervention with an open-mouth exercise device designed to facilitate maximal interincisal opening (MIO) and improve quality of life in patients with head and neck (H&N) cancer and oral submucous fibrosis (OSF). MATERIALS AND METHODS Sixty patients with H&N cancer, OSF, and trismus (MIO < 35 mm) participated in the functional rehabilitation program. An open-mouth exercise device intervention group and conventional group, each consisting of 20 patients, underwent a 12-week training and exercising program and follow-up. For the control group, an additional 20 patients were randomly selected to match the demographic characteristics of the aforementioned two groups. RESULTS The patients' MIO improvements in the aforementioned three groups were 14.0, 10.5, and 1.3 mm, respectively. CONCLUSION Results of this study confirm the significant improvement in average mouth-opening range. In addition, according to patient feedback, significant improvements in health-related quality of life and reductions in trismus symptoms occurred in the open-mouth exercise device group. CLINICAL RELEVANCE This newly designed open-mouth exercise device can facilitate trismus patients with H&N cancer and OSF and improve mouth-opening range and quality of life.