Influence of Dentulous Gum Chewing on Brain Activity

Method: The subjects for this study were 10 dentulous individuals ( 6 mens, 4 women; age; 26-31 years old, average age: 27.9±1.5 years old). All the subjects were fully informed of and consented to the research methods, which had been approved by the ethics committee of Tsurumi University School of Dental Medicine (approval number: 305, August 31, 2005). Brain activity was evaluated by conducting the Neuronal Abnormality Topography (NAT) analysis of electroencephalogram (EEG) immediately before and after gum chewing to obtain normalized power variance (NPV). The EEG recorded for three minutes using ESA-pro (Brain Function Laboratory, Inc., Kanagawa, Japan). For the gum chewing test, xylitol gum (Lotte, Tokyo, Japan) was used for the purpose of determining the chewing ability, and instructions were given to chew the gum on the right side for one minute. A statistical analysis was conducted to compare the NPV values before and after gum chewing using the Wilcoxon’s test (α=0.05).

Result: The average the NPV values of before gum chewing was 1.2436 and after gum chewing was 1.2426 on the motor area of the left side. The average the NPV values of before gum chewing was 1.2445 and after gum chewing was 1.2430 on the sensorial area of the left side. A significant difference was observed on the sensorial and motor area after gum chewing (p<0.05).

Conclusion: The findings from this study indicate that gum chewing on the right side was affected brain activity to the sensorial and motor area on the left side.