The influence of vertical dimension of occlusion changes on the electroencephalograms of complete denture wearers

Purpose: The present study was conducted to identify how changes in the vertical dimension of occlusion (VDO) affect the sensory perception and activity of the brain in complete denture wearers using an electroencephalogram (EEG). Methods: Subjects were 21 individuals wearing complete dentures who regularly visited the Division of Prosthodontics at Tsurumi University Dental Hospital for checkups (12 males and 9 females, average age: 76.6). Based on their original dentures, two duplicate dentures with different VDO (-3 mm and +5 mm) were fabricated. EEG activity and occlusal force were measured before and after gum chewing with each denture in all subjects. Negative indicator scores for psychological conditions and stable neuronal activity (D alpha) were calculated using EEG data. Statistical analysis was performed using the Wilcoxon test to compare changes in the sensory perception, activity of the brain, and occlusal force (alpha = 0.05). Results: After gum chewing with the +5-mm denture, a significant increase was observed in the negative indicator score (p < 0.05). No significant difference was found in the Da values before and after gum chewing with any of the dentures (p > 0.05). A significant decrease was observed in the occlusal force between the original denture and the -3-mm denture (p < 0.05). Conclusion: Psychological condition and occlusal force were influenced by immediate changes in the VDO of the complete denture. (C) 2014 Japan Prosthodontic Society. Published by Elsevier Ireland. All rights reserved.