Effects of a mouth-opening intervention with remote support on adherence, the maximum interincisal opening, and mandibular function of postoperative oral cancer patients: A randomized clinical trial

Purpose: The purpose of the study was to investigate the effects of a mouth-opening intervention for post-operative trismus and remote support provided via telephone following hospital discharge for intervention adherence in patients with oral cancer. Methods: The study is a parallel randomized trial. Patients admitted at a general hospital for oral cancer surgery were recruited and randomly assigned to either the experimental or the active control group. Both groups underwent a 12-week intervention program, including warm compress, masticatory muscle massage, and jaw exercise. Subjects in the experimental group received additional support via telephone following hospital discharge. Data on intervention adherence maximum interincisal opening and mandibular function impairment were collected at baseline, week 4, and week 12. Results: Sixty subjects (30 in each group) that completed the study were included in the analysis. At week 12, the intervention practice time in the experimental group was 299.67 min (95% CI: 223.44-357.89) more than that of the active control group. From baseline to week 12, the change in maximum interincisal opening was 10.30 mm (95% CI: 8.22-12.37) greater in the experimental than in the active control group. The change in mandibular function impairment score was -0.36 (95% CI: -0.44 to -0.28) greater in the experimental than in the active control group. Conclusions: The study results support the effect of remote support via telephone for enhancing adherence to the intervention protocol, and the effect of the intervention program for alleviating trismus and mandibular function impairments in patients who receive curative surgery for oral cancer.