Chewing time and chewing strokes in different dentofacial deformities

Lip and tongue strength associated with chewing patterns in aging population

BACKGROUND

Improving chewing function of older adults increases the health-related quality of life. Few studies indicated the correlation between tongue, lip strength on masticatory performance in older people. The study aimed to investigate the association between lip, tongue strength on chewing pattern in aging population.

METHODS

The older adults had independent daily intake without assistance were enrolled. They had intact dentition and no periodontitis. To estimate the number of chewing strokes and chewing time by consuming a cornstarch cookie were used to represent chewing pattern. Lip and tongue pressure were evaluated with an Iowa Oral Performance Instrument. Linear regression analysis was used to analyze the lip and tongue pressure associated with the chewing time and strokes. Spearman's correlation analysis was utilized to evaluate the associations among chewing time and chewing strokes or lip and tongue pressure.

RESULTS

35 women and 35 men with an average age of 73.2 years were investigated. Tongue pressure was significantly related to the chewing time and the number of chewing strokes (p = 0.01 and 0.03). There was a close association between chewing time and the number of chewing strokes (p < 0.0001). The correlation between lip and tongue pressure was significant (p < 0.0001).

CONCLUSION

The tongue strength significantly related to chewing ability in aging population. Increasing the tongue strength greatly reduced the number of chewing strokes and chewing time. Good masticatory ability could increase the motor function of tongue; raising the tongue strength might be able to improve mastication in older adults.

The use of digital texture image analysis in determining the masticatory efficiency outcome

The mixture level of gum samples consisting of two colours can be assessed visually, using the electronic colorimetric method, employing digital image processing techniques and specially designed software. The study investigates the possibility of an alternative method called "digital texture image analysis" (DTIA) to assess improvement of masticatory efficiency in denture wearers. The objectives were i) to evaluate whether DTIA discriminates changes in the colour mixing ability within a group over time; ii) to determine whether DTIA can be used to detect improvement in chewing ability; iii) to select the most appropriate DTIA feature that sufficiently describes masticatory efficiency in CDs wearers. The study was designed as an intra-individual evaluation of masticatory efficiency, which was assessed in participants with new dentures in three follow-up times. A set of four texture features was used in the current study. Uniformity, Contrast, Homogeneity and Entropy of the obtained chewing-gum samples were correlated to the degree of gum comminution. A statistically significant difference in masticatory efficiency was observed based on the values of the analysed DTIA variables of gum samples-Uniformity, Contrast, Homogeneity, and Entropy-have changed in the participants during the observation period. The improvement of the masticatory function in relation to the mixing ability of two-coloured chewing gum could be traced by monitoring changes in the values of DTIA variables. The most increasement of masticatory efficiency was observed by monitoring DTIA parameters such as contrast, and homogeneity.

The impact of occluding pairs on the chewing patterns among the elderly

OBJECTIVES

This study aims to investigate the impact of occluding pairs (OPs) on chewing strokes, chewing time, mealtime duration, and bite force in an aging population.

METHODS

The 100 participants included 52 women and 48 men with average age of 71.2 years. The subjects were restricted to those who can eat what they wanted and had no temporomandibular joint disorder (TMD) and dysphagia history; their OPs were counted in the posterior occlusal support zone in accordance with the Eichner classification. Free habitual mastication of a cornstarch cookie was analyzed by recording the number of chewing strokes and the amount of time needed for complete mastication. Strokes were counted by considering the opening and closing mandibular movements. Mealtime was defined as the time spent to finish a lunchbox and accomplish swallowing. Bite force was estimated with a T-Scan III®. A linear regression analysis was used to evaluate the impact of the OPs on the chewing strokes, chewing time, mealtime duration, and bite force.

RESULTS

In this study, 76% of the participants had 4 OPs and 12% participants had 3 OPs. Increasing the OPs significantly shortened the chewing time and mealtime duration (P = 0.02). The mealtime duration did not notably affect the chewing time (P = 0.237). There was significant association between OPs and bite force (P < 0.0001).

CONCLUSIONS

In elderly, increasing OPs significantly raised the bite force and shortened the chewing time and strokes. More OPs might be the key to maintain good chewing function.

CLINICAL SIGNIFICANCE

Among the elderly, increasing OPs significantly raised the bite force and shortened the chewing time and mealtime duration. To provide better chewing function, good oral hygiene is important to maintain as many OPs as possible; how to gain more OPs is essential concern in the prosthodontic treatment plan making.

The effect of increased chewing strokes on the DeMeester score

Saliva is known to be protective for esophageal mucosa. Increased chewing strokes result in a quantitative and qualitative enhancement of saliva. Reduction in the amount of saliva produced results in an increased incidence of gastroesophageal reflux disease (GERD), which can be objectively measured by the DeMeester score. The impact of increased chewing strokes on the DeMeester score remains largely unknown, thus this study aimed to find out their impact on the value of the DeMeester score and its individual components.The effect of increased chewing strokes on the DeMeester score was investigated in 12 subjects (5 male and 7 female) who were diagnosed with GERD. All subjects underwent a 48-hour pH monitoring using the Bravo® pH capsule. All the patients chewed their food 20 times more on Day 2 as compared to Day 1. The data were analyzed for change in the DeMeester score and its individual components in 2 days.In patients with GERD (DeMeester score > 14.72 on Day 1), the number of long refluxes (>5 minutes) on Day 2 (mean = 3.2, SD = 2.3) was significantly lower than on Day 1 (mean = 6.4, SD = 2.7); Z = -2.032, p = 0.04. Though, the DeMeester score and its other individual parameters decreased on Day 2, they were not statistically significant.In patients with GERD, increased chewing strokes lead to a decrease in the number of long reflux episodes. Though there is a decrease in the DeMeester score and its other individual components, larger randomized controlled studies are required to reach statistical significance.

Videoendoscopic evaluation of food bolus preparation: A comparison between normal adult dentates and older adult dentates

AIM

Food bolus preparation plays an important role in swallowing food. The ability to carry out oral functions varies with age, and the same might be true of the ability to prepare food boluses. Previously developed methods for assessing food bolus preparation were not able to evaluate swallowed boluses; that is, the boluses were spat out before they were swallowed. The aim of the present study was to evaluate food bolus preparation in older adults using videoendoscopy, and to compare the food bolus preparation abilities of older adults and younger healthy adults.

METHODS

The participants were 30 older adults and 30 younger healthy adults. None of the participants showed any symptoms of dysphagia or eating difficulties. In each examination, an endoscope was inserted into the nasal passage, and the participant was instructed to eat cooked rice. The grinding, mixing and aggregation of each bolus was graded from 0 to 2, with higher numbers indicating more marked grinding, mixing and aggregation. We simultaneously investigated the number of chewing cycles.

RESULTS

The older adults showed higher grinding scores and lower mixing scores than the younger healthy adults. However, neither of these differences was significant. In contrast, the older adults showed significantly lower aggregation scores and carried out a significantly greater number of chewing cycles than the younger healthy adults.

CONCLUSIONS

Using videoendoscopy, we found that older adults showed lower aggregation scores and carried out a greater number of chewing cycles than younger healthy adults. These results suggest that older adults are less able to prepare food boluses than younger healthy adults. Geriatr Gerontol Int 2017; 17: 226-231.

Endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles

It is known that solid food is transported to the pharynx actively in parallel to it being crushed by chewing and mixed with saliva in the oral cavity. Therefore, food bolus formation should be considered to take place from the oral cavity to the pharynx. In previous studies, the chewed food was evaluated after the food had been removed from the oral cavity. However, it has been pointed out that spitting food out of the oral cavity interferes with natural food bolus formation. Therefore, we observed food boluses immediately before swallowing using an endoscope to establish a method to evaluate the food bolus-forming function, and simultaneously performed endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles. The subject was inserted the endoscope nasally and instructed to eat two coloured samples of boiled rice simultaneously in two ingestion conditions ('as usual' and 'chewing well'). The condition of the food bolus was graded into three categories for each item of grinding, mixing and aggregation and scored 2, 1 and 0. The score of aggregation was high under both ingestion conditions. The scores of grinding and mixing tended to be higher in subjects with a high number of chewing cycles, and the score of aggregation was high regardless of the number of chewing cycles. It was suggested that food has to be aggregated, even though the number of chewing cycles is low and the food is not ground or mixed for a food bolus to reach the swallowing threshold.