Relationship of Pressure Pain Thresholds between the Masticatory Muscles and Styloid Process. Part 2. Healthy Subjects and Patients with Temporomandibular Disorders

Purpose: We previously reported correlations between the pressure pain threshold (PPT) at the styloid process, which represents individual pain sensitivity, and PPTs of the masticatory muscles in healthy subjects, and proposed the 95% confidence interval (95%CI) of the PPT at the styloid process as a reference range. In this study, we evaluated its usefulness as a reference range.Methods: Serial changes in the PPT relative to the 95%CI were studied in 7 healthy subjects. Next, the determination of abnormal sites in the PPT relative to the 95%CI was studied in 7 patients with temporomandibular disorders (TMD).Results: In the healthy subjects, the PPT remained within the 95%CI at all sites. Since the PPT deviated from the 95%CI at some sites in TMD patients, abnormal sites could be determined.Conclusion: The 95%CI of the PPT at the styloid process is useful as a means for the evaluation of muscle symptoms of TMD patients.