The prevalence of temporomandibular disorders in patients with chronic whiplash-associated disorder is a controversial issue that may be influenced by the widespread pain character and psychologic distress frequently observed in patients with chronic pain. The aim of this study was to determine the prevalence of temporomandibular disorder pain, widespread pain, and psychologic distress in persons with chronic whiplash-associated disorder pain, using a controlled, single blind study design. The prevalence of temporomandibular disorder pain in the chronic whiplash-associated disorder pain group was compared with 2 control groups: a chronic neck pain group and a no neck pain group.
From 65 persons, a standardized oral history was taken, a physical examination of the neck and the masticatory system was performed, widespread pain was investigated by tender point palpation, and psychologic distress was measured with a questionnaire (SCL-90). Because the recognition of temporomandibular disorder pain and neck pain remains a matter of debate, 3 well-defined classification systems were used: one based on the oral history, a second on a combination of oral history and pain on active movements and palpation, and a third one based on a combination of oral history and function tests.
Irrespective of the classification system used, the chronic whiplash-associated disorder pain group more often suffered from temporomandibular disorder pain (0.001 < P < 0.028) and widespread pain (0.001 < P < 0.003) than the no neck pain group. Moreover, patients with whiplash-associated disorder showed more psychologic distress (0.000 < P < 0.044) than the other 2 groups.
The higher prevalence of widespread pain and psychologic distress in patients with chronic whiplash-associated disorder suggests that the higher prevalence of temporomandibular disorder pain in these patients is part of a more widespread chronic pain disorder.