Relationship between radiographic changes in the temporomandibular joint and bone mineral density: a population based study.

OBJECTIVE. The aim of this population based study was to compare radiographic changes in the temporomandibular joint (TMJ) with the lumbar spine and femoral neck BMD. To find whether there is any relationship between TMJ radiographic changes, vitamin D (25(OH)D) and bone markers levels and the number of missing teeth. MATERIAL AND METHODS. The study included 95 randomly selected participants. Bilateral TMJ images were obtained using an orthopantomograph (OPTG) and were evaluated for presence of radiographic signs. BMD was measured by dual energy X-ray absorptiometry (DXA). BMD of the lumbar spine (LT score) and femur (FT score) was detected by DXA. The level of type I collagen telopeptide fragments (P1NP), of C-telopeptide crosslaps of type I collagen (CTX-1) and of 25(OH)D were also measured. RESULTS. Subjects with a lower LT score had significantly fewer occluding pairs of teeth (p=0.018) and were more frequent users of removable prostheses (p=0.008). Radiographic changes were negatively correlated with P1NP (p=0.041). CTX-1 correlated positively with P1NP (p<0.001) and negatively with 25(OH)D (p=0.042). Occluding pairs of teeth were positively correlated with the LT score (p=0.012) and FT score (p<0.001). Radiography showed changes in the TMJ of 57% of participants. Out of 95 participants, 60% demonstrated an abnormally low LT value. CONCLUSIONS. This population based study indicates that TMJ radiographic changes and teeth loss seems to be related to the low level of BMD and 25(OH)D level.