Evaluation of the electric mouth opener on mouth-opening training effectiveness following temporomandibular joint disc repositioning surgery

doi:10.19438/j.cjoms.2025.06.005

Abstract

Abstract: PURPOSE: To introduce a self-developed electric mouth opener and evaluate its efficacy in postoperative mouth-opening exercise following temporomandibular joint disc repositioning surgery. METHODS: Thirty patients with maximal interincisal opening(MIO) <30 mm after open disc repositioning surgery for anterior disc displacement were randomly assigned to three training groups: manual stretching, stretching device group, and electric mouth opener. All groups underwent 6 weeks of home-based rehabilitation: the manual group performed finger-assisted stretching, the stretching device group used a traditional TMJ stretching brace, and the electric group used the self-developed four-speed adjustable electric mouth opener. MIO, pain degree, and mandibular function evaluated with visual analog scale (VAS) before training, at 2 weeks and 6 weeks after training were recorded and compared. RESULTS: No significant differences in preoperative or postoperative MIO existed among three groups. After 6 weeks of training, all groups showed significant MIO improvement versus baseline (P<0.05). The electric mouth opener group achieved optimal recovery [(39.2±1.5) mm], significantly exceeding both the stretching device group [(35.7±2.8) mm] and manual group [(32.1±4.0) mm]. Pain reduction was most pronounced in the electric group. At 6 weeks, both device-assisted groups showed higher mandibular function scores than the manual group, with the electric mouth opener group showing superior efficacy(P<0.05). CONCLUSIONS: The electric mouth opener is safe and effective for accelerating postoperative MIO recovery in TMJ disc repositioning patients, offering advantages in operational simplicity and stability.

Key words: Temporomandibular joint disc repositioning surgery, Electric mouth opener, Mouth-opening exercise, Maximal interincisal opening

CLC Number:

R782.6

Wang Pengcheng, Gu Zhuming, He Dongmei. Evaluation of the electric mouth opener on mouth-opening training effectiveness following temporomandibular joint disc repositioning surgery[J]. China Journal of Oral and Maxillofacial Surgery, 2025, 23(6): 567-572.

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