Accuracy of newly developed color determination application for masticatory performance: Evaluating color-changeable chewing gum.

PURPOSE: Color-changeable chewing gums are used to evaluate masticatory performance, as measured by a colorimeter or visually based on a color scale. Although anyone can use a color scale, the evaluation accuracy depends on the evaluator. We develop an application that can determine the degree of color change in chewing gum using smartphone images, making color evaluation accurate and easy to measure. METHODS: For the application, 60 chewed gum samples were prepared. Two shots were captured using two smartphone models. To create the application algorithm, a formula was developed to approximately map the color value from the smartphone images to the true value using a colorimeter. A basic validation was performed on 60 new samples covering a range of colors, followed by a field validation on 100 healthy dentate participants aged 20-39 years. RESULTS: The intraclass correlation coefficient for two repeated shots had a high value ≥ 0.97 in the basic and field validations, confirming reliability. No significant differences were observed in the paired t-test and Wilcoxon signed-rank test, and a significant and strong correlation (correlation coefficient ≥ 0.92) was observed between the evaluation values using the colorimeter and the basic and field validations. Bland-Altman plots further confirmed the validity of the application. CONCLUSIONS: A software application was developed to enable easy, quick, and accurate determination of the masticatory performance of a chewing gum from images taken using a smartphone with highly reliable and validated results.

Association between Masticatory Performance, Nutritional Intake, and Frailty in Japanese Older Adults.

The older adult population in Japan is expected to increase. Therefore, long-term care and frailty prevention are important. However, the relationship between masticatory performance, nutritional intake, and frailty remains unclear. This cross-sectional study aimed to examine energy, protein, and vitamin D intake and its association with frailty and masticatory performance in older adults. Patients between January 2022 and January 2023 were recruited and divided into robust and frail groups. Masticatory performance, nutrition, frailty, and other data, such as age and sex, were evaluated through onsite measurements and a questionnaire. Logistic regression analysis was conducted with frailty as a dependent variable and masticatory performance as an independent variable, adjusting for age, sex, skeletal muscle mass, living alone, energy intake, protein-energy ratio, and vitamin D intake. No significant differences were observed between the groups regarding age or sex. The robust group showed significantly better results for protein-energy ratio, vitamin D intake, and subjective and objective masticatory performance than the frail group. Logistic regression analysis revealed a significant correlation between skeletal muscle mass, protein-energy ratio, and objective masticatory performance with frailty. Masticatory performance was associated with frailty, independent of the intake of nutrients such as energy, protein, and vitamin D.

Factors Associated with Selection of Denture Adhesive Type: A Cross-Sectional Survey.

The type of denture adhesive, cream or home-liner, chosen by regular denture adhesive users and oral conditions contributing to this selection require elucidation. The factors associated with denture adhesive selection were investigated through a face-to-face survey on oral and denture conditions. Age, sex, oral moisture, masticatory performance, retention and stability of the removable denture, ridge shape, mucosal thickness, and duration of denture use were examined in cream and home-liner-type denture adhesive users who did not regularly visit a dentist. Univariate analysis and multivariate analyses were performed. There were 38 and 40 cream-type and home-liner-type adhesive users, respectively. The type of denture adhesive was significantly associated with the oral moisture value, retention, ridge shape, mucosal thickness, and duration of denture use in univariate analyses. The residual ridge conditions with large factor loadings for ridge shape and mucosal thickness and duration of denture use were significantly related to the denture adhesive selection in multivariate logistic analysis. The residual ridge conditions and duration of denture use were significant factors in the selection of cream- and home-liner-type denture adhesives. These results can provide appropriate guidance based on the adhesives patients without dental supervision are more likely to choose.

Factors related to masticatory performance in junior and senior high school students and young adults: A cross-sectional study.

PURPOSE: Maintaining good masticatory function from a young age promotes lifelong health, yet limited studies have explored masticatory performance in young individuals. We investigated the relationship of sex, age, and individual oral functions with masticatory performance among junior and senior high school students and young adults. METHODS: This cross-sectional study included students aged 12-13, 14-15, and 16-17 years (groups S1, S2, and S3, respectively) and young adults aged 20-40 years (group YA). We assessed oral functions, the number of functional teeth, and anthropometric measurements. Masticatory performance was evaluated using color-changeable chewing gum. We analyzed sex-related differences in each group and age-related differences in each sex. Multiple linear regression analysis was performed using masticatory performance as the dependent variable to investigate related factors. RESULTS: Among the 522 children and 100 young adults, males exhibited significantly higher masticatory performance than females in groups S1, S3, and YA. Among males, groups S2, S3, and YA exhibited significantly higher masticatory performance than group S1. Among females, group S2 exhibited higher masticatory performance than groups S1 and S3. Male sex, the maximum occlusal force and tongue pressure, and the number of functional teeth were significantly correlated with masticatory performance. CONCLUSIONS: Masticatory function development differed by sex, with males exhibiting higher masticatory performance than females. We identified that male sex, the maximum occlusal force and tongue pressure, and the number of functional teeth were significantly associated with masticatory performance. Our findings provide a basis for masticatory performance assessment in different age groups.

Gender differences in the relationship between personality, cognitive function and regular dental visits in Japanese community-dwelling older adults.

OBJECTIVES: Studies have examined the association between personality and health behaviour, but research focusing exclusively on regular dental visits has yet to be conducted. This study examined the association between personality traits and regular dental visits among Japanese community-dwelling older adults. METHODS: The participants in this cross-sectional study included 1,057 community-dwelling older adults aged 65-74 years from Ranzan and Yoshimi towns; data were collected from October to November 2015 and October to November 2016, respectively. Interviews were conducted to obtain sociodemographic, income, occupation and medical data. The Tokyo Metropolitan Institute of Gerontology Index of Competence was used to assess higher-level competence; general intelligence was also evaluated. The 'Big Five' personality traits-openness to experience, consciousness, neuroticism, extraversion and agreeableness-were also examined. A multivariable logistic regression analysis was performed to examine the relationship between regular dental visits and personality traits. RESULTS: Among men, the number of natural teeth, current employment status and conscientiousness were associated with dental care utilization. Among women, the number of natural teeth, current annual income, the intellectual activity domain of the Tokyo Metropolitan Institute of Gerontology Index of Competence and openness were significant. CONCLUSIONS: The factors associated with regular dental visits differed by gender. Overall, work was associated with men's visits, whereas intellectual activity and economic factors were relevant to women. Factors such as personality traits should be considered when addressing barriers to oral health. Understanding personality traits will help practitioners more effectively encourage older adults to make dental visits.

Age and sex differences in oral functions from junior high school to young adulthood: A cross-sectional study.

BACKGROUND: As oral function requires maintenance throughout life, it needs to be understood across age groups; however, few studies have investigated this in young individuals. OBJECTIVES: To clarify age and sex differences in maximum occlusal force, maximum tongue pressure and tongue-lip motor function; and the relationship among these oral functions in junior high school students and young adults. METHODS: This cross-sectional study investigated oral functions in students aged 12-13 years, 14-15 years old and 16-17 years old (S1, S2 and S3), and young adults aged 20-40 years (YA). We analysed age group differences in each sex and sex differences in each age group. Multiple linear regression analysis was performed for each sex using the maximum occlusal force as the dependent variable to investigate the associations among different oral functions. RESULTS: In 522 children and 100 young adults, there were significant increases in oral functions with age in males and a significant decrease in maximum tongue pressure between S2 and S3 in females. Maximum occlusal force and tongue pressure were higher in males than in females in S3 and YA; tongue-lip motor function was higher in females than in males in S1. In multiple linear regression analysis, tongue-lip motor function and age group were significant factors in both sexes and in males, respectively. CONCLUSION: Maximum occlusal force, maximum tongue pressure and tongue-lip motor function increased with increasing age groups in males. Our findings provide a basis for assessing oral function across age groups.

The Association between Dietary Habits and Periodontal Disease in Young Adult Women.

Dietary habits of middle-aged and elderly individuals affected by periodontal disease (PD) differ from those who are unaffected by it, according to previous reports. However, in young adults, there are only a few reports that show a correlation between nutrient/food intake and PD. Moreover, no report till date has assessed the correlation between dietary habits and PD using a self-administered diet history questionnaire (DHQ). Therefore, we assessed this correlation using a DHQ in young adult women who are likely to develop PD. The participants were enrolled from 2 universities and included 120 female college students a mean age of 20.4 y. The participants were assessed for the presence of PD according to the community periodontal index and were divided into two groups, the PD group and the non-PD group. Their dietary habits were investigated using a DHQ and the level of difficulty in chewing food was assessed. The PD group had a significantly lower nutrient intake of minerals, fat-soluble vitamins, water-soluble vitamins, and dietary fiber than the non-PD group. In terms of food groups, the PD group consumed significantly lesser amounts of green and yellow vegetables (GYV) than the non-PD group. Multivariate analysis revealed that the PD group had significantly lower intakes of vitamin E and GYV than the non-PD group. The PD group consumed significantly lesser amounts of hard foods than the non-PD group. In conclusion, young adult women who were evaluated for PD by a screening test had a significantly lower nutrient/food intake than those without a PD.

Utilization of denture adhesives and the factors associated with its use: a cross-sectional survey.

BACKGROUND: An increase in the number of elderly edentulous patients likely leads to a greater demand for dentures and denture adhesives. As denture adhesives have both positive and negative features, dentists need to know the types of denture adhesive users to be able to provide instruction to denture wearers on how to use denture adhesives effectively. This study aims to examine the utilization of denture adhesives and associated factors. METHODS: Seven closed-ended questionnaires were developed for a web-based survey. After that, Fisher's exact tests were performed to determine the difference in the denture adhesive usage rate by gender, type of denture, last dental visit, and smoking status. A multivariate-adjusted logistic regression analysis was performed with denture adhesive use or non-use as the dependent variable and the other items as independent variables. Next, Fisher's exact tests and a multivariate-adjusted logistic regression analysis were performed with the type of denture adhesives as the dependent variable in the same way. Statistical analyses were performed for all denture wearers, complete denture wearers, and partial denture wearers. The level of statistical significance was set at p = 0.05. RESULTS: A total of 1470 denture wearers in Japan participated in this study. Of these, 318 used denture adhesives, while 212 (66.7%) used cream; 74 (23.3%) used home liner; 25 (7.9%) used powder; four (1.3%) used sheets; and three (0.9%) used several types. The Fisher's exact tests revealed that the ratios of using denture adhesives were significantly higher for complete denture wearers (p < 0.001), last dental visit over 1 year (p = 0.005), and smokers (p = 0.005). For partial denture wearers, the ratio was significantly higher in smokers (p = 0.262). The multivariate adjusted logistic regression revealed that denture adhesive use or non-use were significantly associated with the type of denture and smoking status in all denture wearers, and just smoking status in partial denture wearers. There were no significant results about the type of denture adhesive selection. CONCLUSIONS: From all denture wearers, complete denture wearers and smokers are more likely to use denture adhesives. In addition, smokers significantly use denture adhesives if they are partial denture wearers.

Factors related to removable denture use in independent older people: A cross-sectional study.

BACKGROUND: Denture use for recovery of major tooth loss can reduce the need for care, and thus, it is important for dentists to identify the types of patients who use removable dentures. OBJECTIVE: To identify factors associated with removable denture use in independent older Japanese people. METHODS: This cross-sectional study investigated the oral condition; demographics; lifestyle; dental visit behaviour; and higher-level functional capacity, as assessed using the Tokyo Metropolitan Institute of Gerontology index of competence (TMIG index), of independent older people aged 65-74 years. Participants were divided into four groups based on sex and condition of the posterior occluding pairs (POPs). Multivariate-adjusted logistic regression analyses were performed for each group, with denture use or non-use as the dependent variable and the other items as independent variables. RESULTS: Denture use or non-use was significantly associated with only dental consultation behaviour (regular dental visits and time since the last dental visit) in all groups. Subsequent analyses excluding dental consultation behaviour demonstrated that denture use or non-use was significantly associated with educational background in female participants with decreased POPs, with the type of household in male participants with lost POPs and with the TMIG index (social role) in female participants with lost POPs. CONCLUSIONS: Denture use was associated with dental consultation behaviour. We revealed factors related to denture use or non-use in females with decreased POPs and both males and females with lost POPs.

Association between chewing-stimulated salivary flow under the effects of atropine and mixing ability assessed using a color-changeable chewing gum.

PURPOSE: To assess the time course of chewing-stimulated salivary flow after oral atropine administration, and determine the association between chewing-stimulated salivary flow and mixing ability using color-changeable chewing gum in dentate adults. METHODS: Ten healthy dentate adults were administered 1mg oral atropine to induce mouth dryness. The subjects' chewing-stimulated salivary flow was assessed using the Saxon test. They were then asked to rinse their mouth with tap water for 15s, and to chew on color-changeable chewing gum for 60s at a constant rate of 60 cycles per min. This procedure was performed before, and at 10-min intervals for up to 120min after the atropine administration. The experiment was repeated after 1 week. Steel's test was used to compare the chewing-stimulated salivary flow rates at each time point after atropine administration with the baseline value. The effect of the stimulated salivary flow rates on the degree of color change was analyzed using linear mixed effects models, with the stimulated salivary flow rates as fixed factors and subjects as the random factor. RESULTS: Chewing-stimulated salivary flow showed a significant decrease from 50 to 120min after oral atropine administration (P<0.05) and the amount of chewing-stimulated salivary flow had a significant effect on the color change of the color-changeable chewing gum (P<0.001). CONCLUSIONS: We observed a decrease in stimulated salivary flow after orally administering 1mg atropine, and a positive association between mixing ability using color-changeable chewing gum and chewing-stimulated salivary flow in dentate subjects.

Reliability and validity of a quantitative color scale to evaluate masticatory performance using color-changeable chewing gum.

In the present study, we developed a novel color scale for visual assessment, conforming to theoretical color changes of a gum, to evaluate masticatoryperformance; moreover, we investigated the reliability and validity of this evaluation method using the color scale. Ten participants (aged 26.30 years) with natural dentition chewed the gum at several chewing strokes. Changes in color were measured using a colorimeter, and then, linearregression expressions that represented changes in gum color were derived. The color scale was developed using these regression expressions. Thirty-two chewed gums were evaluated using colorimeter and were assessed three times using the color scale by six dentists aged 25.27 (mean, 25.8) years, six preclinical dental students aged 21.23 (mean, 22.2) years, and six elderly individuals aged 68.84 (mean, 74.0) years. The intrarater and interrater reliability of evaluations was assessed using intraclass correlation coefficients. Validity of the method compared with a colorimeter was assessed using Spearman's rank correlation coefficient. All intraclass correlation coefficients were > 0.90, and Spearman's rank-correlation coefficients were > 0.95 in all groups. These results indicated that the evaluation method of the color-changeable chewing gum using the newly developed color scale is reliable and valid.

Properties of a color-changeable chewing gum used to evaluate masticatory performance.

PURPOSE: To clarify the basic properties of a color-changeable chewing gum to determine its applicability to evaluations of masticatory performance under different types of dental status. METHODS: Ten participants with natural dentition aged 26-30 years chewed gum that changes color during several chewing strokes over five repetitions. Changes in color were assessed using a colorimeter, and then L*, a*, and b* values in the CIELAB color system were quantified. Relationships between chewing progression and color changes were assessed using regression analysis and the reliability of color changes was assessed using intraclass correlation coefficients. We then measured 42 dentate participants (age, 22-31 years) and 47 complete denture wearers (age, 44-90 years) to determine the detectability of masticatory performance under two types of dental status. RESULTS: Regression between the number of chewing strokes and the difference between two colors was non-linear. The intraclass correlation coefficients were highest between 60 and 160 chewing strokes. Dentate and edentulous groups significantly differed (Wilcoxon rank sum test) and values were widely distributed within each group. CONCLUSIONS: The color of the chewing gum changed over a wide range, which was sufficient to evaluate the masticatory performance of individuals with natural dentition and those with complete dentures. Changes in the color values of the gum reliably reflected masticatory performance. These findings indicate that the color-changeable chewing gum will be useful for evaluating masticatory performance under any dental status.