The worth of sound recording as evaluation criteria of response to surgery in non-reduced anterior disc dislocation

Aim: The objective of the present study was to examine whether joint sounds are objective criteria for evaluating the success of surgery for non-reduced anterior disc dislocation. Method: Twenty-seven patients (age, 35.6 ± 10.6 years; female/male, 22:5) with non-reduced disc dislocation, as confirmed by MRI, were included in the study. Temporomandibular joint (TMJ) sounds were assessed and digitized by custom-made device. As a surgical treatment, all patients underwent "disc plication technique". The success of surgery was evaluated with maximal interincisial opening (MIO), pain, patient satisfaction scores, MRI examination, and TMJ sound intensity. Recording of sounds of TMJ and pain and satisfaction scores were repeated again at postoperative 12 months and compared to preoperative results. Results: Mean preoperative sound intensities with jaw opening and closing and left-right movement were 79.37 ± 3.52 dB and 81.0 ± 4.99 dB, respectively. Mean postoperative sound intensity with jaw opening and closing was 64.81 ± 4.54 dB whereas that with left-right movement was 65.6 ± 5.38 dB. Examination of preoperative and postoperative sounds showed that decreased volume level related with clinical improvement and postoperative replaced disc image in MRI. MIO values increased from 25.89 ± 1.76 mm to 34.26 ± 1.403 mm. Postoperative pain scores were lower than preoperative period and patient satisfaction improved markedly. Conclusion: The results of this study showed that patients who underwent plication for non-reduced disc dislocation had clinical improvement, which was related with the decreasing volume level of the click sound, reducing the pain, improving satisfaction, and replacing the disc to normal position in MRI.