Candidate risk factors for temporomandibular pain and dysfunction syndrome: psychosocial, health behavior, physical illness and injury.

The purpose of this paper is to identify potential risk factors for the temporomandibular pain and dysfunction syndrome (TMPDS). The investigation focuses on the relations of TMPDS to personal, social and recent experiential factors, especially health behaviors and physical illnesses and injuries, that contribute to life stress. The data come from a retrospective case-control study of 151 TMPDS patients and 139 healthy controls. Results show that cases and controls are similar on most measures of personality characteristics although cases are somewhat more external in locus of control expectancy and appear far more distressed than do controls. There are no case/control differences in reports of desirable and undesirable life events that do not involve physical illness and injury. The social situations of cases and controls differ in that cases have fewer sources of emotional support than controls. No differences were found in the proportion of cases and controls who reported that they ever ground or clenched their teeth, although cases were told they do so more frequently by dentists than were controls. Excluding never married women, cases were less likely than controls to have children. This could not be explained on the basis of birth control and may provide a clue to a biologic base for the much higher rates of women than men who are treated for TMPDS. Cases reported more past pain-related illnesses, more life-threatening physical problems and more recent events involving injury and non-pain-related physical illnesses. There was no difference between cases and controls in reports of physical problems prior to age 13. TMPDS patients appear to be unusually distressed individuals who are beleaguered by physical illnesses and injuries as well as by pain, who tend to attribute their fate to external factors, and who have fewer sources of emotional support.