Comparison of two scales in the assessment of muscle and joint palpation tenderness in chronic temporomandibular disorders.

Following the guidelines of the Craniomandibular Index, 23 chronic patients had 42 muscle and temporomandibular joint sites palpated. Two- and four-point scales were generated in response to the patient's reactions. After 6 weeks of treatment, patients measured with the 2-point scale showed 6.39% improvement in muscle tenderness and patients measured with the 4-point scale showed a 14.99% improvement. These changes were significantly different. Correlation between scales was r = .88 originally and increased to r = .91 after 6 weeks. Results showed that the 4-point scale is significantly more able to detect clinical changes in muscle and joint tenderness than is the 2-point scale.