Toni J. (T.J.) Hanson, M.D. from the Mayo Clinic, and R. L. Redfern, D.D.S., of Colorado Springs, CO, collaborated together to present a case study via a poster presentation on the effect of bisphosphonates (BPH) has on the temporomandibular joint (TMJ).
Stage “0” (no open oral lesions) bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been reported, and this can also include the TMJ. The TMJs are loaded synovial joints. Compromised joints are more reactive than normal joints under load with more resultant stresses and remodeling, and BPH is attracted to areas of bone reactivity. Stage “0” BRONJ occurs within the bone, while osteonecrosis undermines the cortical layer, which can lead to collapse of the cortex of the mandibular condyles. This results in a change of articular dimension which will cause a change in occlusion and biomechanics. This further need for accommodation increases muscular activity, load on the injured joints, headache and cervicothoracic aggravation.
For their case study, they presented their patient who was a 62-year-old vocal teacher referred by ENT for a progressive six-month history of otalgia, facial, TMJ region and subsequent neck pain. The pain severity and frequency varied in association with jaw opening, biting, and vocalizations. On examination, she had mildly reduced oral opening, as well as tenderness with palpation, which was greatest in the muscles of the mastication. Imaging including plain radiographs and CT was unrevealing. The MRI revealed mixed T1 and T2 signals consistent with osteonecrosis of the condylar head of the mandible. She had a history of osteopenia which had been treated for one to two years with a bisphosphonate.
Based on this finding, the bisphosphonate was discontinued; an MPO (MutuallyProtective Occlusal) intraoral orthosis was used to decrease muscle hyperactivity and to improve jaw biomechanics; and physical therapy was conducted for the myofascial pain and joint mobility component. In addition diet modification (soft diet) was implemented. Her pain improved significantly, although the superior portion of the mandibular condyle eventually collapsed due to osteonecrosis. She was, however, able to continued her career as a vocal teacher.
To read the authors' conclusions and see images from their case study, please review the poster.