Sir, a 26-year-old female presented to the oral surgery department in July 2020 with severe, diffuse, non-specific pain in the oro-facial region. Over the preceding two months, she reported recurrent and progressively deteriorating episodes of pain. No history of jaw locking, clicking or grinding/clenching habit nor any recent life stressors noted. Medically, she is fit and well and takes no regular medications. She is a non-smoker, drinks less than four units of alcohol a week and works as a dental core trainee within a dental hospital. On examination, the muscles of mastication were tender on palpation bilaterally with no other abnormalities. A DPT radiograph was taken to exclude any dental pathology. A GAD-7 and HADS score was completed, which noted no symptoms of generalised anxiety or depression.

In view of the spontaneous nature of her symptoms and a lack of relevant co-morbidities, we were keen to investigate for any potential contributors to this pain. A pain diary recorded by the patient revealed recurrent episodes of pain precipitated by wearing an elastomeric respirator when carrying out AGPs. The patient had been fit-tested for a reusable elastomeric respirator and Pure Flo Size: Small was selected.

In the acute phase, conservative management involved regular pain relief, soft diet, hot/cold compress and limiting mouth opening. We encouraged avoiding the use of a respirator for two weeks. At review, she reported a significant improvement in her symptoms and no further episodes of pain. A diagnosis of acute TMJ dysfunction - myofascial pain was confirmed.

The patient noted use of the respirator induced clenching and inadvertently postured the mandible forward. Prolonged forced posture in this way causes mechanical stress on the TMJ and associated structures. Similar findings have been reported in a group of scuba divers when using mouthpieces propelling unnatural mandibular positioning, consequently placing significant stress on the TMJ.1

Despite fit-testing to determine the most appropriate size mask to use, she continued to develop TMD symptoms, highlighting the need to also consider comfort beyond accomplishing a tight seal. To prevent future episodes of pain, we suggested the use of a hood powered air purifying respirator (PAPR) which does not exert pressure on the temporo-mandibular joint system.2 Failure to tackle this potential complication early may create a group of professionals with chronic TMD, known to be a difficult entity to manage.