Signs and symptoms associated with TMD in adults with shortened dental arches

This study investigated the prevalence of signs and symptoms associated with temporomandibular disorders (TMD) in adults with shortened dental arches in Tanzania.

The shortened dental arch group comprised 725 subjects with an intact anterior region and zero to eight occluding pairs of teeth posteriorly. They were categorized into five groups according to length and symmetry of the dental arches. A control group of 125 subjects with complete dental arches was included. The subjects were interviewed with questions related to pain and sounds within the temporomandibular joints and restricted mobility of the mandible. Clinical examination consisted of registration of clicking or crepitation of the joints, measuring maximum mouth opening, and assessing occlusal tooth wear.

Joint sounds were reported significantly more frequently by subjects with posterior support only unilaterally (17%) and by subjects with no posterior support (10%) compared to other categories of dental arches (3% to 5%). No significant differences were found between categories of dental arches with respect to pain (2% to 9%), restricted mobility of the mandible (0% to 1%), maximum mouth opening < 40 mm (0% to 3%), or clicking or crepitation of the joints (12% to 23%). For the younger age group (> or = 20 and < 40 years), tooth wear occurred significantly more often in subjects with no posterior support. For the older age group (> or = 40 years), tooth wear increased significantly with decrease of posterior support.

No evidence was found that shortened dental arches provoke signs and symptoms associated with TMD. However, when all posterior support is unilaterally or bilaterally absent, the risk for pain and joint sounds seems to increase.