Abstract
The purpose of this study is to document the improvement observed in two cases of Parkinson’s disease (PD) after dental treatment. The first subject is a man in his 60s with severe Parkinson’s disease; medication has not been very effective in this case. Prior to treatment, he was unable to stand without support due to rigidity. Just after removing as much of the dental infection as possible, he was able to walk, albeit slowly, and as a result of continuing treatment, one month later, the symptoms had significantly improved. The second subject is a woman in her 40s, who became aware of joint stiffness seven years ago, and was later diagnosed with PD independently at three hospitals. Her main symptoms were rigidity, knee pain, and speech disorder. The dopamine medication worked well against rigidity, but the symptoms reappeared after the medication stopped working. Her condition was significantly improved just after one tooth with an apical lesion was extracted. Although the underlying mechanism has not been clarified, I hypothesize that, at least in these cases, negative signals that passed through the trigeminal nerve to the midbrain affected predominantly the dopaminergic neurons in the substantia nigra of the midbrain. Removal of the harmful signals from the oral area resulted in normalization of the substantia nigra. Further research should be promoted with dental and medical cooperation.