Relation between osteoporosis and radiographic and clinical signs of osteoarthritis/arthrosis in the temporomandibular joint: a population-based, cross-sectional study in an older Swedish population

Objective: The aim was to elucidate the relation between osteoporosis and osteoarthritis/arthrosis (OA) in the temporomandibular joint (TMJ). Background: General epidemiological data support the hypothesis that osteoporosis and OA are inversely correlated but is not conclusively investigated in the TMJ. Materials and methods: A group of 114 representative elderly women and men, randomised from a comprehensive population study in Gothenburg, Sweden, had bone mineral density established with whole-body, dual-energy X-ray absorptiometry (DXA) as part of a health survey. In addition, dental examinations were performed, including panoramic radiographs exposed as an overview of the TMJ's and jaws. In 88 of the 80-year-old participants (48 women and 40 men), a clinical orofacial examination according to the RDC/TMD system was performed. Results: A diagnosis of osteopenia/osteoporosis was found in 36% of the 114, with a statistically different greater proportion of women. Condylar alterations evaluated from panoramic radiographs were observed in 34%, with no significant gender difference. No significant differences were found in the proportion of individuals with osteopenia/osteoporosis and any condylar radiographic alteration or not. Forty-one of the clinically examined subjects, 47%, fulfilled the criteria for an RDC/TMD diagnosis with no gender difference. All participants graded the orofacial pain as low chronic pain. An opening capacity of <40 mm denoted a higher risk of having pain in the temporomandibular system. No association was found between clinical diagnosis of RDC/TMD and osteopenia/osteoporosis. Conclusion: The prevalence of osteopenia/osteoporosis appears not to be of importance for radiological or clinical findings of OA in the TMJ.