The purpose of this study was to clarify the presence or absence of changes in mandibular movement during thechewing of various foods. Healthy dentate adults with a masticatory performance above the standard value (150 mg/dL)participated in this study. Mandibular movement when chewing softened gum for 20 s on the habitual chewing side was recordedusing a Motion Visi-Trainer. The masticatory movement path patterns were classified into five types, and 20 adults(10 men, 10 women; average age, 27.1 years) who showed normal patterns were asked to chew three foods (gummy jelly,peanuts, and beef jerky), and their mandibular movements were recorded. The opening distance, masticatory width, andcycle time were calculated as quantitative parameters. The path patterns and quantitative parameters of the four foodswere compared. The pattern of the masticatory movement path when chewing various foods was the same, and no changeswere observed owing to the different foods. The opening distance and masticatory width were similar for gummy jelly andchewing gum but were significantly larger for beef jerky and chewing peanuts. For cycle time, there were cases wherethere was a significant difference between the two foods, and cases where there was no significant difference. These resultssuggest that in healthy dentate adults with good masticatory function, the pattern of the masticatory movement path doesnot change when chewing various foods; however, the amount of movement is greater when chewing peanuts or beef jerkythan when chewing gum or gummy jelly.

This study aimed to clarify the output variation of the sensor of a developed prototype occlusal force measuring device. In Experiment 1, for 10 sensors using a calibration pressure device, seven types of loads from 100 to 700 N, in increments of 100 N were applied to the pressure sensitive part of each sensor three times. After recording the resistance values, the differences between the measurements and the sensors were investigated. In Experiment 2, the resistance value when a load of 100–700 N was applied to the pressure sensitive part of each sensor was measured on different days for 3 days, and the daily variation was investigated. In Experiment 1, no significant differences were observed among the three measurements; however, a significant difference was observed between the sensors. In Experiment 2, no differences were observed in the resistance values measured over 3 days for each sensor. Based on these results, the sensor of the developed prototype occulusal force measuring device showed no variation owing to repeated measurements, but variation was observed between sensors. Therefore, it is necessary to calibrate each sensor individually. Furthermore, no daily variations were observed in the output of any sensor, suggesting that the output was reproducible.

The purpose of this study was to clarify the effects of different chewing postures and tastes on brain function.This study included 10 healthy participants. The participants were asked to chew rice in four different postures（sitting, 60°supine,30°supine, and horizontal）, and changes in the masseter muscular activity and cerebral blood flow were recorded andcompared between the four postures（Experiment A）. Brain waves were recorded while participants chewed three types ofgummy jellies with different levels of bitterness （non-bitter, slightly bitter, and bitter）, and the alpha- and beta wave contentswere compared before and after chewing and between foods（Experiment B）. In experiment A, the integrated valueof masseter muscular activity during chewing rice was similar in all postures, and no significant difference was found betweenpostures. The change in cerebral blood flow was greatest in the sitting position, followed by the 60°supine, 30°supineposition, and the horizontal position, in that order, and a significant difference was found between all two postures. In experimentB, the content of alpha- and beta-waves for the non-bitter gummy jelly showed no significant change before and afterchewing, however, the content of alpha waves for the bitter gummy jelly significantly decreased and beta waves significantlyincreased. Comparing between foods, the content of alpha waves after chewing was highest when chewing the non-bittergummy jelly, followed by chewing the slightly bitter gummy jelly and then chewing the bitter gummy jelly. The content ofbeta waves after chewing was lowest when chewing the non-bitter gummy jelly, followed by the slightly bitter gummy jellyand then the bitter gummy jelly. These results suggest that differences in the chewing postures and tastes affect brainfunction.

Purpose: Oral dryness caused by side effect of medicines has been increasing in elderly. The aim of this study was to investigate the relationship between protein ingredient and salivary volume on oral dryness patients caused by calcium blocker and healthy elderly.

Methods: Six patients taking calcium blocker and six healthy elderlies were enrolled. Unstimulated salivary volume and protein concentration were investigated. iTRAQ proteomic analysis was performed to detect all salivary proteins. The relation between salivary volume and the ratio of the intensities of western blotting product to that of β-Actin was investigated. The relation between protein concentration per salivary volume and the ratio of the intensities of western blotting product to that of β-Actin was also examined.

Results: As the result of iTRAQ proteomic analysis, 968 kinds of salivary proteins were detected. Calmodulin-like protein 3 was included with a constant rate in the saliva of oral dryness patients, and less likely to detect on the saliva of healthy elderly. Glutathione S-transferase P was detected with a constant rate in the saliva of oral dryness patients, but it also included in saliva of healthy elderly.

Conclusions: These results indicated that calmodulin-like protein 3 tended to be detected on the saliva of oral dryness patients caused by calcium blocker.

An 85-year-old man presented to our hospital with a fractured mandibular complete denture. The denture was temporarily attached to the fractured part. A silicone rubber impression material was used to obtain the impression of the mucosa under the denture base. Occlusal recording material was inserted on the occlusal surface of the artificial teeth, and maxillomandibular relationship record was performed to obtain an increase of approximately 2 mm in vertical dimension. After the working model containing the existing dentures and the opposing dentition model were attached to the articulator using occlusal record, the occlusal surface of the artificial teeth of the existing dentures was reshaped with wax. After scanning the modified denture with an E3 dental scanner, the denture base and artificial teeth were designed separately and saved in the STL format. After the support design was performed using Carima Slicer V2, the denture base and artificial teeth were modeled using an S-WAVE 3D printer IMD-S. After the modeling was completed, cleaning, support removal, post-polymerization, and polishing were performed, and the denture base and artificial teeth were bonded using Digital Denture Bond, an adhesive material for denture bases. After wearing the new denture, a masticatory performance test was conducted by measuring the amount of glucose eluted, and the results showed that the patient had good masticatory performance. These findings suggest the usefulness of applying digital technology to create new dentures in cases of denture fractures and a decrease in the occlusal vertical dimension.