Joint sounds and signs of temporomandibular disorder: a comparative study by means of manual palpation and computer-based vibrational analysis

Abstract

Both vibrational analysis and clinical examination have been claimed to identify intracapsular temporomandibular joint (TMJ) disorders, particularly disc displacements. The purpose of this study was to evaluate the interexaminer consensus on detecting TMJ sounds and to compare this with the results obtained through a computerized system (SONOPAK). The sample was composed of 45 people and it was divided in 2 groups: an experimental group of 24 patients presenting with TMJ complaints (sounds and/or pain), and a control group of 19 individuals with no obvious signs or symptoms of temporomandibular disorders. Sixty-seven percent of the patients were females with a mean age of 36 years. The control group was gender- and age-matched with the test group. Temporomandibular joint electrovibratography (JVA) was performed on the whole sample by one examiner. This was followed by light manual palpation of the TMJs by 2 examiners, who were not calibrated and were not aware of the results of the previous vibratographic (EAV) examination. Both examiners were unaware of which group was being examined. Indices of agreement and the Cohens kappa test were used to analyze the data. A prevalence of 62.5% and 42.1% of TMJ sounds was found for the experimental and control groups, respectively. Indices of agreement ranged from 32% to 100% and kappa index ranged from 0 to 0.4 for all conditions investigated (opening and reciprocal clicking, crepitation, and terminal thud). Although acceptable agreement was achieved, the values for kappa index were considered poor for all variables (fair agreement is considered between 0.4 and 0.75). Temporomandibular joint sounds are commonly found in both patients and nonpatients, but their detection and classification are difficult, even when an electronic device is employed. Although the sample in this study was small, the results indicate that electrovibratography (JVA) should be used with caution, and that interexaminer calibration may improve the identification of joint sounds.