PURPOSE: In patients with oral cancer, trismus (maximum interincisal opening 
[MIO] <35 mm) can develop as a result of surgery and radiotherapy. The aim of 
this study was to provide an alternative operation to both eradicate oral cancer 
and prevent postsurgical trismus.
MATERIALS AND METHODS: In our retrospective cohort study of oral cancer patients 
who underwent operations during 2010 to 2014, the predictor variable was the 
type of operation (alternative operation or traditional operation) and the 
outcome variable was MIO. All of the cases were allocated by 2 periods: the 
traditional operations were performed from 2010 to 2011, and the alternative 
operations were performed from 2011 to 2014. All patients received marginal 
mandibulectomy, anterolateral thigh free flap, and adjuvant radiotherapy or 
concurrent chemoradiotherapy. In addition to traditional marginal 
mandibulectomy, the alternative operation included ipsilateral coronoidectomy 
and myotomy of the temporalis muscle insertion, masseter muscle, and medial 
pterygoid muscle. MIO was measured at 10 time points. The adjusted variables 
included demographic data, diagnostic parameters, treatment, and response.
RESULTS: Of the 36 male patients with oral cancer, 16 were placed in the 
alternative operation group (AOG; mean age, 53.5 ± 11.9 years) and 20 were 
placed in the traditional operation group (TOG; mean age, 50.7 ± 7.1 years). 
Regarding the outcome indicator of patient MIO, the preoperative MIO in the AOG 
was on average 7.5 mm shorter than that in the TOG (P < .01), but it was 
consistently superior to the MIO in the TOG after the operation. Multivariate 
analysis of variance showed that patients in the AOG were more likely to have 
postoperative non-trismus.
CONCLUSIONS: The alternative operation exhibited superior postoperative MIO 
values and similar postoperative complication rates. For the prevention of 
trismus, it is practical to perform the combined operation simultaneously, 
cutting all ipsilateral jaw closing muscles and the coronoid process and 
eradicating the tumor.