Effect Of High Power Laser On Radiotherapy Induced Trismus.

Inclusion Criteria: * head and neck cancer patients who complain of decreased mouth opening and received or receiving radiotherapy. * patients who complain from pain and inflammation in the tempromandibular joint due to radiotherapy. * radiotherapy should be above 40 GY. * patient ages between 20 to 65 years old. Exclusion Criteria: * patients with poor general health. * patients with difficulties in filling questionnaire. * patients who are complaining of other tempomandibular problems other than trismus such as (disc discplacement and trumatic mandibular fractures.