Could different TMJ disc positions observed in MRI cause different sounds? Analysis on a group of subjects with ADD with reduction: a pilot study.

AIMS: Magnetic resonance imaging (MRI) is the method of choice for examining soft-tissue pathology of the temporomandibular joint (TMJ). MRI shows a high spatial resolution with accuracy for the identification of internal derangement. Tasaki developed a classification system for disc displacement in the TMJ, identifying eight different types of disc displacements in addition to the superior disc position. This study aims to test the ability of electrosonography (ESG) in discriminating different kinds of disc displacement according to the disc position criteria proposed, comparing the ESG results with those obtained by MRI. METHODOLOGY: Twenty-seven patients were selected from an initial group of 50 patients with articular disc displacement, selected by means of clinical examinations, according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and who had both MRI and ESG studies performed. For each patient and for each peak in ESG, both in the opening and closing movements, three different parts of the sound were analyzed. The frequency (Hz) and the mean amplitude (µV) of the sounds were calculated in the three analyzed windows. Afterwards, gathering the data for the Tasaki's classes and dividing opening and closing sounds, the number of peaks was calculated, as well as average and standard deviations for both the Hz and µV. RESULTS: The peak frequency shows significant differences between different disc positions during the first and second third of the opening phase and during the first third of the closing phase. The peak amplitude shows significant differences between different disc positions during all of the opening and closing phases. CONCLUSIONS: Although limited by sample size, the present study shows the presence of different sounds with different Hzs and µVs associated with different disc positions that were recorded with ESG.

Effects of the acupoints PC 6 Neiguan and LR 3 Taichong on cerebral blood flow in normal subjects and in migraine patients.

Acupuncture has been proven to be effective in the treatment of various cardiovascular disorders; it acts both on the peripheral flow and on the cerebral flow. Our study aimed to evaluate the effects of the insertion of PC 6 Neiguan and LR 3 Taichong acupoints on the cerebral blood flow (CBF) in the middle cerebral artery (MCA). These effects were measured in a group of patients suffering from migraine without aura (Group M) and in a healthy control group (Group C). In the study, we included 16 patients suffering from migraine without aura, classified according to the criteria of the International Headache Society, and 14 healthy subjects as a control group. The subjects took part in the study on two different days, and on each day, the effect of a single acupoint was evaluated. Transcranial Doppler was used to measure the blood flow velocity (BFV) in the MCA. Our study showed that the stimulation of PC 6 Neiguan in both groups results in a significant and longlasting reduction in the average BFV in the MCA. After pricking LR 3 Taichong, instead, the average BFV undergoes a very sudden and marked increase; subsequently, it decreases and tends to stabilize at a slightly higher level compared with the baseline, recorded before needle insertion. Our data seem to suggest that these two acupoints have very different effects on CBF. The insertion of PC 6 Neiguan probably triggers a vasodilation in MCA, while the pricking of LR 3 Taichong determines a rapid and marked vasoconstriction.

Diagnostic concordance between MRI and electrovibratography of the temporomandibular joint of subjects with disc displacement disorders.

OBJECTIVES: The aim of this study is to evaluate the diagnostic concordance of MRI and electrovibratography (EVG) of the temporomandibular joint (TMJ) in the diagnosis of articular disc displacement with reduction (ADDwR) and articular disc displacement without reduction (ADDw/oR). METHODS: 50 patients (12 males, 38 females; mean age 37.46 ± 15.64 years) with a hypothesis of disc displacement were selected. For each patient an MRI of the TMJ was performed. MRIs were evaluated sorting the 100 TMJs by kind of pathology (no pathology, ADDwR, ADDw/oR, and joint hypermobility). Afterwards, the patients had an EVG exam. The EVG exams were performed with vibration transducers over each TMJ, enabling simultaneous, bilateral recording of vibrations emanating from joint sounds during the opening and closing movements. The presence of a sound peak was compared with the MRI diagnosis of ADDwR, while a multipeak aspect was compared with ADDw/oR diagnosis using Cohen's kappa test. RESULTS: The presence of a peak-shaped track has high specificity for ADDwR (90.27%). The Cohen's kappa calculated for the ADDwR was 0.5615 (good-moderate). The presence of a multipeak-shaped track has low specificity (65.22%) and sensitivity (70.42%). The Cohen's kappa calculated for the ADDw/oR was 0.2992 (poor). CONCLUSIONS: The present study recommends the use of EVG to support the clinical diagnosis of a disc displacement with reduction when MRI is not available or when subjects cannot be investigated by MRI.