Abstract:
The evaluation of temporomandibular joint (TMJ) sounds has been considered as an integral part of the physical examination for temporomandibular disorders (TMD). To evaluate the usefulness of TMJ vibration analysis, 297 joints from TMD patients were diagnosed by lower joint arthrography and videofluoroscopy. The surface vibrations of TMJ were recorded with electovibratography. The following four conditions were statistically discriminated by multivariate analyses of the frequency components: (I) meniscal displacement with reduction; (II) meniscal displacement with partial disk reduction; (III) meniscal displacement without reduction; and (IV) degenerative joint disease and/or perforation of the disk. Using the total vibration energy as a threshold, the diagnostic sensitivity was 82%, while the diagnostic specificity was 75%. Discriminate analysis for the above-mentioned four conditions revealed the diagnostic sensitivity of 79%, 80%, 77%, and 76%, and the diagnostic specificity of 76%, 86%, 59%, and 78% for conditions I, II, III, and IV, respectively. It was concluded that the vibration analysis of the TMJ could be clinically useful as a routine examination tool for TMD patients.