Assessing Older Adults’ Masticatory Efficiency

Does occlusal morphology of artificial teeth improve chewing of removable dentures wearers? A systematic review and meta-analysis

PURPOSE

This systematic review aimed to verify whether anatomic, semi-anatomic, or nonanatomic occlusal morphology of artificial teeth improves the masticatory function of complete or removable partial denture wearers.

MATERIALS AND METHODS

According to the PICO strategy, six databases and the grey literature were searched to identify randomized (RCT) and non-randomized clinical trials (N-RCT) comparing masticatory function, in terms of masticatory performance and efficiency, and muscle activity as primary outcomes; and patient-reported results (O) in individuals using removable dentures (P) with different occlusal morphologies of artificial teeth (I/C). Masticatory ability, satisfaction with the prosthetic treatment, and oral health-related quality of life (OHRQoL) were evaluated as secondary outcomes. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB 2.0) for RCT and Risk of Bias for non-randomized studies with intervention (ROBINS-I) for N-RCT studies. Meta-analyses were performed to compare primary outcomes and masticatory ability between the occlusal morphologies of artificial teeth of complete or removable partial dentures (α = 0.05). Certainty of the evidence was verified using the GRADE approach.

RESULTS

Eleven studies (seven RCTs and four N-RCTs) were included. The risk of bias was considered low for two studies, some concerns for five, and high for the last four studies. Meta-analyses showed that removable partial dentures with anatomic artificial teeth improved masticatory efficiency for carrot chewing (MD 6.31; 95% CI [3.39, 9.22], I2 = 0%). However, masseter and temporal muscle activities increased when removable partial dentures with nonanatomic teeth were used (MD -756.97; 95% CI [-892.25, -621.68], I2 = 100%). Masticatory ability was not influenced by occlusal morphology during chewing of all foods in complete denture users: Carrot (MD -0.88, 95% CI [-8.98, 7.23], I2 = 57%); sausage (MD -8.86, 95% CI [-23.05, 5.33], I2 = 71%); apple (MD -5.78, 95% CI [-28.82, 17.26], I2 = 87%); and cheese (MD -4.16, 95% CI [-15.14, 6.82], I2 = 62%). The certainty of evidence for all evaluated outcomes was very low, mainly due to very serious problems found in the parameters of inconsistency, indirectness, and imprecision.

CONCLUSIONS

Despite the very low certainty of evidence, the occlusal morphology of artificial teeth influences masticatory function. Anatomic teeth improved the masticatory efficiency and muscle activity of removable partial denture wearers. Nonanatomic teeth increased temporal and masseter muscle activity, which negatively affected chewing in removable partial denture users. However, patients using complete dentures with anatomic and semi-anatomic teeth presented similar masticatory ability.

Association between oral health and locomotive syndrome: a cross-sectional study in Japanese adults

BACKGROUND

Many studies have examined the association between oral health, care needs, and physical function, but few have focused on the association between oral health and locomotive syndrome (LS). We examined the association between LS and oral-health status, such as the number of teeth and chewing function, in an adult population.

METHODS

The study included 2888 participants who underwent examinations of motor function and oral health. Individuals with LS stage 1 or higher were classified as having LS, while others were classified as not having it. Logistic regression analysis was performed using the presence or absence of LS as the dependent variable and age, sex, smoking status, drinking habit, exercise habit, walking speed, history of stroke, bone density, body mass index, metabolic syndrome, chewing function, and the number of teeth as independent variables to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for each independent variable.

RESULTS

When the number of teeth and chewing function were included separately in multivariate analyses, the OR for LS was significantly higher for participants with 0-19 teeth than for those with 28 teeth, and for participants with poor chewing function than for those with good function (adjusted ORs, 1.47 [95% CI, 1.01-2.15] and 1.73 [95% CI, 1.37-2.18], respectively). In analyses that included tooth number and chewing function as a combined independent variable, relative to individuals with 28 teeth and good masticatory function, the adjusted ORs were 2.67 (95% CI, 1.57-4.52) for those with 28 teeth and poor chewing function, 1.63 (95% CI, 1.20-2.22) for those with 20-27 teeth and poor chewing function, and 1.83 (95% CI, 1.06-3.18) for those with 0-19 teeth and poor chewing function.

CONCLUSION

Having fewer teeth and poor chewing function may be associated with LS. The maintenance of masticatory function may be important to prevent LS in adulthood.

Association of self-rated chewing function and oral health status with metabolic syndrome

PURPOSE

The study aimed to examine the association of self-rated chewing function, the number of teeth and periodontal status with metabolic syndrome.

METHODS

The participants were 11,119 adults aged 40-74 years who underwent specific health checkups, including an oral health examination, in 2018 in Japan. This study used the standard questions of the specific health checkups to obtain information on self-rated chewing function. A multinomial logistic regression analysis was performed with metabolic syndrome status as the dependent variable, and age, sex, lifestyle questions, self-rated chewing function, number of teeth, and periodontal status as the independent variables.

RESULTS

Number of teeth and periodontal status were significantly associated with metabolic syndrome after adjusting for confounding variables. Self-rated chewing function was significantly associated with metabolic syndrome in the crude analysis, but not after adjustment for confounding variables. Both number of teeth and periodontal status were significantly associated with self-rated chewing function.

CONCLUSION

There was no significant direct association between self-rated chewing function and metabolic syndrome. Self-rated chewing function may be an indicator of poor oral condition that links to metabolic syndrome.

Development a new chewing problem directory and its validation for Korean elders

Objectives

This study aimed to develop a new chewing problem directory (CPD) and validate it with oral health indicators such as total occlusion force, number of natural and rehabilitated teeth (NRT), NRT posterior, natural teeth, natural teeth posterior, and dental status among Korean elders.

Background

Chewing problem is the main oral health problem in elders. However, there has been no validated tool using both subjective and objective assessment of chewing problem.

Subjects and methods

A total of 537 participants aged 65 years or more were randomly assigned into 2 subsamples: developing sample (n = 260) for developing and internally validating the new CPD as the 1st stage and confirmation sample (n = 277) for confirming validation of CPD as the 2nd stage. CPD was developed using three subjective questionnaires (general eating, chewing nuts, and chewing meat problem) and objective NRT. Periodontitis, age, sex, education, smoking, alcohol drinking, metabolic syndrome, and frailty were considered as confounders. Following the development of CPD, CPD was validated using multiple multivariable logistic regression after controlling for confounders in confirmation sample and total sample.

Results

The Cronbach’s alpha value for three subjective questionnaires of CPD was 0.87. Among oral health indicators, NRT (0–28) showed the highest impact association with subjective chewing problem score (partial r = − 0.276). The chewing problem from the new CPD was associated with all items of oral health indicators. The prevalence of chewing problems by CPD was 57.7% in developing sample. Elders with NRT ≤ 24, compared with those with NRT ≥ 25, showed the highest impact on chewing problems by new CPD (Odds Ratio = 7.3 in the confirmation sample and 5.04 in the total sample, p < 0.05) among oral health indicators.

Conclusion

This new CPD was developed as a valid tool to evaluate the chewing problem for Korean elders in dental clinics and community-based settings.

Patient-reported outcome measures for masticatory function in adults: a systematic review

Objective

The aim of this systematic review was to critically evaluate the Patient-Reported Outcome Measures (PROMs) for masticatory function in adults.

Methods

Five electronic databases (Medline, Embase, Web of Science Core Collection, CINAHL Plus and APA PsycINFO) were searched up to March 2021. Studies reporting development or validation of PROMs for masticatory function on adults were identified. Methodological quality of the included studies was evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) risk of bias checklist. Psychometric properties of the PROM in each included study were rated against the criteria for good measurement properties based on the COSMIN guideline.

Results

Twenty-three studies investigating 19 PROMs were included. Methodological qualities of these studies were diverse. Four types of PROMs were identified: questions using food items to assess masticatory function (13 PROMs), questions on chewing problems (3 PROMs), questions using both food items and chewing problems (2 PROMs) and a global question (1 PROM). Only a few of these PROMs, namely chewing function questionnaire-Chinese, Croatian or Albanian, food intake questionnaire-Japanese, new food intake questionnaire-Japanese, screening for masticatory disorders in older adults and perceived difficulty of chewing-Tanzania demonstrated high or moderate level of evidence in several psychometric properties.

Conclusions

Currently, there is no PROM for masticatory function in adults with high-level evidence for all psychometric properties. There are variations in the psychometric properties among the different reported PROMs.

Trial Registration PROSPERO (CRD42020171591).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01949-7.

Textural properties and muscle activities during mastication of normal and ultrasonically softened sticky rice aimed for consumers with swallowing disorder: A pilot study

Ultrasonication was used to develop softer sticky rice for elder adults. Textural properties of original sticky rice (oSR) and ultrasonically modified sticky rice (mSR) were determined. In addition, jaw muscle activities during mastication of both oSR and mSR were investigated. Twenty-seven healthy elderly subjects, age 68.9 ± 7.6 years, were asked to masticate both types of sticky rice in random sequence for three times with a 5-min rest between each test. Activities of bilateral masseter and suprahyoid muscles were recorded. Root mean square (RMS) and mastication duration were analyzed. After mastication trials, subjects were asked to rate preference and softness of the samples. mSR exhibited significantly lower hardness than oSR, while cohesiveness and adhesiveness values of the two samples were not significantly different. Interestingly, all the muscle activities were not significantly different between masticating oSR and mSR, whereas the number of chewing cycles while chewing the mSR was larger. However, 92% of the subjects preferred mSR and felt that it was softer. mSR may therefore be regarded as having potential for elder people who have difficulty masticating hard solid foods based on its lower hardness and higher level of preference compared to oSR.

Masticatory Adaptation to Occlusal Changes

This review deals with the frequent wide variability of masticatory capacity/incapacity. Neither researchers nor clinicians have taken sufficient account of this variability despite its implications for nutrition. Mastication in normal healthy oral conditions is first described, followed by a short presentation of the mechanisms of masticatory adaptation in the nervous system. Capacity, incapacity, and successful compensatory adaptation of mastication are then defined, along with the different methods used for their evaluation. Examples of adaptation needs are given, such as those concomitant with dental wear or occlusal changes. Finally, given its vital importance for deeply impaired mastication/deglutition function, the impact of masticatory adaptation processes on nutrition is examined.

Which variables should be controlled when measuring the granulometry of a chewed bolus? A systematic review

The distribution of food particles in a chewed bolus characterizes the food destruction after food oral processing (FOP). Previous reviews report that it could be affected by a lot of parameters as the number of chewing strokes, the dental status, but the conditions for producing reproducible data allowing inter-studies comparison have not been clearly described yet. This systematic review aims to identify the variables that can affect bolus granulometry determination, and to calculate their relative weights in the median particle size (D₅₀ ) variations. The systematic review focuses on granulometry expressed as D50 of the most used foods (peanuts, carrots, and almonds) and materials (Optosil and Optocal). Based on 58 studies, 5 variables among 60 being extracted could explain the D₅₀ variations. Conceptual differences between the conditions for FOP should be considered. After Chewing-test, the bolus is collected after a predefined number of strokes and its granulometry characterizes the effects of the dental and muscular apparatus on food destruction, while after Mastication-test the bolus is collected at the swallowing threshold, and its granulometry reflects the outcome of the abilities of the subject to adapt his/her mastication behavior to food texture. Experimental conditions related either to physical sieving or image analysis used to analyze the collected boluses impact the D₅₀ values. Finally, when type of test, sieving conditions, type of food or material, number of chewing strokes, and the oral status of the subjects are controlled, mean D₅₀ values are reproducible and could be used for inter-studies comparisons. PRACTICAL APPLICATIONS: This review provides tables that could be useful to control mean D₅₀ variations in further research.

Factors related to dissociation between objective and subjective masticatory function in Japanese community-dwelling elderly adults

Clinicians' evaluations of older adults sometimes reveal inconsistencies between objective and subjective dental status. This study investigated which factors contribute both to good objective masticatory function (OMF) and the poor subjective masticatory function (SMF) that often becomes a clinical issue. Study participants included 635 elderly community-dwelling Japanese adults who underwent a comprehensive geriatric health examination in 2012. SMF was assessed with a question from the Kihon Checklist on eating difficulties (poor or good). OMF was assessed by a colour-changing gum (poor or good). Also investigated were age, sex, depressive symptoms, instrumental activities of daily living (I-ADLs), number of people who joined the participant at dinner, grip strength, usual walking speed, number of remaining teeth, number of functional teeth and their occlusal force. The group with good OMF and good SMF, defined as group 1, and the group with good OMF but poor SMF, group 2, were compared. Logistic regression analyses confirmed that the number of remaining and functional teeth participants had was statistically unrelated to differences between OMF and SMF. Instead, differences were related to stronger depressive symptoms (OR = 1.67, CI = 1.14-2.44), less ability to conduct I-ADL activities (OR = 0.73, CI = 0.59-0.91), slower usual walking speeds (OR = 0.18, CI = 0.06-0.58) and less occlusal force (OR = 0.99, CI = 0.99-1.00). Depressive symptoms, I-ADLs, and physical function are shown to be significantly related to divergence between objective and subjective masticatory function in elderly Japanese. This suggests that dissociations between objective and subjective dental evaluations of elderly adults indicate need for assessment of their mental and physical function.

Relationship between occlusal force and falls among community-dwelling elderly in Japan: a cross-sectional correlative study

BACKGROUND

Falls may cause serious health conditions among older population. Fall-related physical factors are thought to be associated with occlusal conditions. However, few studies examined the relationship between occlusal force and falls. To identify the association between occlusal force and falls among community-dwelling elderly individuals in Japan, public health nurses conducted a cross-sectional descriptive study.

METHODS

We performed extensive physical assessments of five items: maximum occlusal force, handgrip strength, maximal knee extensor strength, one-leg standing time with eyes open and body sway. We also conducted a questionnaire survey concerning the participants' demographic characteristics, health status and fall experience during the past year. Mean scores and standard deviations were calculated for age and the total points of the index of activities of daily living. Associations were examined using Mann-Whitney tests and logistic regression.

RESULTS

We examined 159 community-dwelling people aged ≥65 years, who were independent and active, including 38 participants (24.5%) with experience of falls in the past year. Maximum occlusal force had significant correlation with handgrip strength, maximal knee extensor strength, and one-leg standing time and body sway (P < .05, respectively). We found weak associations between participants with and without a history of falls in terms of the five physical measurements. Logistic regression analysis showed that fall experience was significantly associated with maximum occlusal force (P = 0.004).

CONCLUSIONS

This is the first study, led by public health nursing researchers, to examine the associations between maximum occlusal force and falls among community-dwelling elderly in Japan. The results showed that maximum occlusal force was significantly related to the other four extensive physical assessments, and might also suggest that maximum occlusal force assessment by public health nurses could contribute to more sophisticated and precise prediction of fall risks among the community-dwelling elderly. The latest occlusal force measurement device is non-invasive and easy to use. Public health nurses can introduce it at periodical community health checkup assembly events, which might contribute to raising awareness among community-dwelling elderly individuals and public health nurses about fall prevention and prediction.

Dental status, oral prosthesis and chewing ability in an adult and elderly population in southern Brazil

OBJECTIVE

The objective of this study was to explore the factors associated with inadequate chewing in an adult and elderly population of a city in the southern region of Brazil.

METHODS

This was a cross-sectional study based on a population home-based inquiry (DCH-POP) in southern Brazil. Individuals were interviewed by trained interviewers to create a standardized procedure. In a pilot study, the Questionnaire of Human Communication Disorders (DCH-POP) was created and validated to identify self-reported speech and language, swallowing and hearing disorders. The outcome was dichotomized into either having adequate chewing or not, as assessed by a series of questions about chewing ability. Analyses of absolute and relative frequencies were measured according to the studied variables. A Poisson regression was applied at a significance level of 5%.

RESULTS

A total of 1,246 people were interviewed. Inadequate chewing was found in 52 (5.6%) individuals, with a higher prevalence in the elderly (11.8%) than in adults (5.2%). In the final model, the following factors were associated with inadequate chewing: being 61 years of age or older (prevalence ratio or PR=9.03; 95% CI: 1.20-67.91), loss of teeth and use of unadjusted prosthesis (PR=3.50; 95% CI: 1.54-7.95), preference for foods of soft consistency (PR=9.34; 95% CI:4.66-8.70) and difficulty in nasal breathing (PR=2.82; 95% CI: 1.31-6.06).

CONCLUSION

Age, oral health status through dental prosthesis, preference for foods of soft consistency and difficulty breathing through the nose were factors associated with chewing inability in adults and the elderly.

Factors affecting masticatory function of community-dwelling older people: Investigation of the differences in the relevant factors for subjective and objective assessment

OBJECTIVE

This study aimed to examine relevant factors for subjective and objective assessment of masticatory functions and elucidate any differences between the two methods.

BACKGROUND

Previous studies have reported that the results of subjective and objective assessment of masticatory function in older people do not necessarily agree.

MATERIALS AND METHODS

This study included 487 community-dwelling Japanese older people (205 male and 282 female; mean age 74.1±6.3 years) who participated in a comprehensive geriatric health examination. Basic information (gender and age), higher level of competence in daily living, depression, subjective masticatory function (SMF) and objective masticatory function (OMF) assessments, cognitive function, skeletal muscle mass, handgrip strength, gait speed and oral status (number of remaining and functional teeth, mouth dryness and occlusal force) were recorded.

RESULTS

Multiple logistic regression analysis showed that depression (odds ratio [OR]: 1.181, 95% confidence interval [CI]: 1.094-1.275), mouth dryness (OR: 2.037, CI: 1.212-3.423) and occlusal force (OR: 0.997, CI: 0.996-0.999) were significantly associated with SMF, whereas higher level of competence in daily living (OR: 0.730 CI: 0.586-0.910), skeletal muscle mass (OR: 0.521 CI: 0.283-0.960), number of functional teeth (OR: 0.862 CI: 0.775-0.959), number of remaining teeth (OR: 0.868 CI: 0.810-0.930) and occlusal force (OR: 0.994, CI: 0.991-0.998) were associated with OMF.

CONCLUSION

Subjective masticatory functionSMF and OMF were associated with different factors, suggesting that both mental and physical factors should be taken into consideration when treating decreased masticatory function.

Relation entre la mastication et la qualité de l'alimentation des aînés de l'Étude longitudinale québécoise sur la nutrition et le vieillissement (NuAge)

The objective of this study was to assess the relationship between the quality of mastication and dietary intake among community-dwelling older adults (67-84 years). A secondary analysis of data collected upon entry of participants in the NuAge study was effected. Perceived masticatory efficiency (n=1793) was measured using a questionnaire inspired by the Oral Health Impact Profile. Direct assessment of masticatory efficiency was carried out in a subsample (n=94), using a validated clinical test (Swallowing Threshold Test Index, 0-100%). Dietary intake was calculated from three non-consecutive 24h recalls. Mean scores indicate good perceived masticatory efficiency (Men:26.22±0.19/28;Women:25.81±0.21/28), but weak assessed efficiency (Men:60.8% [CI(57.3-64.2)]; Women:61.2% [CI(57.7-64.7)]). Multivariate regression analysis, adjusting for confounding variables (age, sex, schooling, living alone, income, smoking, chronic conditions, functional autonomy), showed that masticatory efficiency (measured or perceived) was not associated with intake of fruits/vegetables, protein, vitamin C or folic acid.