Management of restricted mouth opening due to Temporomandibular joint disorders

Background

Restricted mouth opening, which is also known as Limited mouth opening, trismus, or lockjaw, has several causes and Temporomandibular joint disorders are considered as the main cause.

Purpose

This study aimed to retrospectively review the causes of restricted mouth opening due to TMJ and its management.

Study design

A retrospective cohort study of subjects who underwent Management of locked jaw Due to TMJ. A total of 879 consecutive patients with locked jaw in the period from 2016 to 2022 were reviewed for the causative factor and its management.

Main outcome variable(s)

maximum inter-incisal opening (MIO in mm), pain in the TMJ (Yes/No) using the visual analogue score (VAS).

Results

the final sample consisted of 409 patients. Irreducible disc displacement represented 60 % of the total cases (245 patients with mean age 31.7 ± 5.5). Followed by TMJ osteoarthritis which represented 12 % (48 patients with mean age 38.4 ± 8.3), Joint adhesion Secondary to Immobilization (9 %), post-surgical represented 8.5 %, Anchored disc phenomenon (7.5 %). While ankylosis, coronoid hyperplasia, radiotherapy, were represented only 3 % (14 patients). Arthrocentesis with joint injection successfully used in treatment of 394 (96 %). Out of them, 21 patients didn't respond to the arthrocentesis and treated by second intervention with TMJ arthroscopy level II. 6 patients with TMJ ankylosis treated with Hegab protocol while one patient with failed joint prosthesis was treated with Total joint replacement.

Conclusions

Arthrocentesis with joint injection could be used effectively in most cases of locked jaw secondary to TMJ. While TMJ arthroscopy could be used in un-responded cases.