Effect of occlusal support by implant prostheses on brain function.

PURPOSE The present study was carried out to identify how gum chewing with and without occlusal support by implant prostheses affects brain function as well as chewing function. METHODS Twenty-four subjects rehabilitated with implant-supported fixed prostheses were evaluated. An electroencephalograph (EEG) (ESA-Pro) and mandibular kinesiograph (Bio PAK(®)) wear used to measure brain function and chewing function, respectively, before and after gum chewing with and without an implant superstructure. Based on brain function estimated by the Dα values derived from measurement data, the subjects were divided into the normal region group (including the sub-normal region group) (n=15; Dα≥0.952) and the impaired region group (n=9; Dα<0.952). All the data were statistically analyzed using the Wilcoxon test (α=0.05). RESULTS Brain function in the normal region group showed no change after gum chewing, whether or not an implant superstructure was in place (p>0.05). However, brain function in the impaired region group showed significant improvement after gum chewing (p<0.05). Seven of 9 subjects using an implant superstructure in impaired region group indicated an increase or no change in brain function compared to the results without an implant superstructure. In the impaired region group, there was a high positive correlation between brain function and masticatory movement (γ=0.75). CONCLUSIONS Subjects in the impaired region group revealed a strong positive correlation between brain function and masticatory movement, indicating that occlusal support by implant-supported fixed prostheses has the potential to enhance brain function.