Purpose: In this study, we examined the hypothesis that uncontrolled oxidative stress causes collapse of the lubrication system, which is considered a major initiator of temporomandibular joint (TMJ) dysfunction. The oxidative stress was evaluated by measuring the overall antioxidant capacity of the low-molecular-weight antioxidants in the TMJ, using cyclic voltammetry (CV), in synovial fluid from normal and anchored disc phenomenon (ADP) TMJs.
Materials and methods: Synovial fluids samples were taken from 13 normally functioning and 33 ADP TMJs. The samples were frozen initially on collection and analyzed in CV to measure their overall reducing power.
Results: CV measurements of the fluids collected from 90% of the healthy joints showed an anodic waves at peak potential [Ep(a)1/2] of 290 +/- 30 mV. Of the samples 56% showed another wave at 650 +/- 100 mV. These waves were generally absent in the fluid collected from ADP TMJs, but 2 new waves at 465 +/- 90 mV and greater than 750 mV were detected in 68% and 87% of the patients, respectively.
Conclusions: The results show more anodic waves, most of which of higher potentials (greater than 750 mV) in ADP TMJs, indicating that the capacity to cope with oxidative stress is lower in these joints. It is not clear whether this is due to absence of low-molecular-weight antioxidants or their consumption by uncontrolled production of reactive oxygen species, which might be the initial step in the collapse of the lubrication system.
Copyright 2002 American Association of Oral and Maxillofacial Surgeons