A comparison of colorimetric and visual methods for the assessment of masticatory performance with color-changeable chewing gum in older persons.

BACKGROUND/PURPOSE: Color-changeable chewing gum is used for the evaluation of masticatory performance. However, it is currently unclear whether colorimetric and visual assessment methods yield consistent results. This study aimed to clarify the consistency between colorimetric and visual methods used for the evaluation of color changes in color-changeable chewing gum. MATERIALS AND METHODS: The sample comprised 644 older persons (mean age, 75.4 ± 6.4 years). The chewing gum was masticated 60 times at the participant's own chewing rate and then expectorated. The color of the chewing gum was evaluated with the ΔE values and a∗ values, measured using a colorimeter, and the 10 Color Shades (10CSh) and 5 Color Scales (5CSc), using visual evaluation. Spearman's correlation analysis was performed to examine the correlation between the results obtained by the four methods. The significance level was set at α = 0.05. RESULTS: The ΔE values, a∗ values, 10CSh scores, and 5CSc scores were all significantly correlated. The highest correlation coefficient (0.979) was between the ΔE values and a∗ values. The lowest correlation coefficient (0.847) was between the a∗ values and 5CSc scores. Decreased masticatory performance was observed with increased age. CONCLUSION: Significant correlations were found for all four methods used in the assessment of masticatory performance with color-changeable chewing gum. While visually based assessments are valid, colorimetric methods are more sensitive to smaller changes in masticatory performance.

A 2-year longitudinal study of the relationship between masticatory function and progression to frailty or pre-frailty among community-dwelling Japanese aged 65 and older.

BACKGROUND: An association has recently been reported between frailty and reduced masticatory function; however, the causal relationship remains unclear. OBJECTIVE: The aim of this study was to clarify the relationship between masticatory function and frailty progression. METHODS: Among 6699 individuals aged 65 and older (mean age 72.8 ± 5.2 years) who were invited to participate in comprehensive medical check-ups, 418 who underwent examinations at the Tokyo Metropolitan Institute of Gerontology in both 2013 and 2015 and who met inclusion criteria were included in this study. Frailty was determined with the Kihon Checklist developed by the Japanese Ministry of Health, Labour and Welfare. The following three masticatory functions were evaluated: occlusal force, mixing ability and subjective chewing ability. The following confounding factors were investigated: age, sex, grip strength, comfortable walking speed, Mini-Mental State Examination (MMSE) score, Self-Rating Depression Scale (SDS) score, skeletal mass index (SMI), number of medications taken and number of remaining teeth. Statistical analysis was performed with binomial logistic regression analysis. RESULTS: Logistic regression analysis revealed that comfortable walking speed, SDS score, MMSE score and masticatory function were significantly related to progression to frailty or pre-frailty. Of the three masticatory function items evaluated, mixing ability and subjective chewing ability were related to frailty progression. CONCLUSION: Our results confirm that masticatory function was associated with the progression to pre-frailty or frailty among community-dwelling individuals 65 years and older over the 2-year period of this longitudinal study. Of the masticatory function items evaluated, mixing ability and subjective chewing ability were associated with frailty progression.

Time-dependent effects of tongue cleaning with mouthwash or mouth moisturising gel on the number of microbes on the tongue surface of elders with care needs.

OBJECTIVE: The purpose of this study was to investigate time-dependent change in the number of microbes on the tongue surface after tongue cleaning using a mouthwash or mouth moisturising gel for elders fed with a feeding tube and with care needs. MATERIALS AND METHODS: Twelve elders fed through a feeding tube and with care needs participated in this prospective crossover study. There were four kinds of tongue cleaning modes as follows: (i) tongue cleaning with a mouthwash; (ii) tongue cleaning with a mouth moisturising gel; (iii) tongue cleaning with water; (iv) no tongue cleaning as a negative control. The total number of microbes on the tongue surface was measured using a rapid oral bacteria detection device at baseline, immediately after cleaning, and at 1, 3 and 5 hours after cleaning to evaluate the time-dependent change for each tongue cleaning mode. RESULTS: There were no significant differences regarding microbial count on every measurement in negative control and tongue cleaning with water. There were significant decreases immediately after cleaning, and at 1, 3 and 5 hours after cleaning compared to baseline when the tongue was cleaned with a mouthwash. There was a significant decrease between baseline and immediately after cleaning when the tongue was cleaned with a mouth moisturising gel. CONCLUSION: Tongue cleaning with mouth moisturising gel decreased the number of microbes on the tongue surface immediately after cleaning, and tongue cleaning with mouthwash decreased it for 5 hours.