Assessment of oxidative stress on occlusal adjustment using ESR technique

Objectives:

In recent years, we have established the novel assessment of the oxidative stress in the rodent brain using by electron spin resonance (ESR) technique. In addition, it has reported that the biting as oral function could reduce the oxidative stress in the brain of rat induced by the physical stress. In this study, we reported that novel assessment of the oxidative stress with occlusal adjustment in the rodent brain using ESR technique.

Methods:

Animals used spontaneously hypertensive rat (SHR) which was reported high oxidative stress in the brain. We divided the experimental group into 3 groups; control, occlusal interference, and occlusal adjustment. We treated with the metal cover (thinness; 1 mm) on molar of SHR in the occlusal interference group. The period of occlusal interference was 4 weeks. We removed the metal cover in the occlusal adjustment group before measuring L-band ESR. After the experimental period, we administered3-methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-yloxy (MC-PROXYL) as nitroxyl spin probe, which was blood-brain-barrier permeable, via the tail vein. We measured the decay rate constant of MC-PROXYL in the isolated brain of SHR by using L-band ESR technique.

Results:

The decay rate constant of MC-PROXYL in the occlusal interference group increased compare to the control group. In addition, the occlusal adjustment group was recovered the decay rate constant of MC-PROXYL in the isolated brain treated with occlusal interference.

Conclusions:

We succeeded in evaluating the increase of the oxidative stress in the isolated rat brain treated with occlusal interference, directly. Furthermore, occlusal adjustment reduced the enhanced oxidative stress in the brain of rat treated with occlusal interference. Taken together, it would be likely that we develop the novel assessment of the oxidative stress in the brain of rodent model on the occlusal treatment in the near future.