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

Association of tooth location, occlusal support and chewing ability with cognitive decline and incident dementia

AIM

Emerging evidence suggests association of tooth loss with impaired cognition. However, the differential effects of anterior versus posterior tooth loss, occlusal support loss and chewing ability are not considered comprehensively.

MATERIALS AND METHODS

We conducted cross-sectional (N = 4036) and longitudinal analyses (N = 2787) on data from Health 2000 and 2011 Surveys for associations of posterior occlusal support loss, anterior versus posterior tooth loss, and chewing ability with baseline cognition and 11-year cognitive decline. Additionally, 15-year incident dementia risk was investigated (N = 4073).

RESULTS

After considering relevant confounders and potential reverse causality bias, posterior occlusal support loss significantly increased dementia risk across all categories indicative of posterior occlusal support loss (hazard ratios [HRs] between 1.99 and 2.89). Bilateral inadequate posterior occlusal support was associated with 11-year decline in overall cognition (odds ratio [OR] = 1.48:1.00-2.19), and unilateral inadequate posterior occlusal support with total immediate (OR = 1.62:1.14-2.30) and delayed recall decline (OR = 1.45:1.03-2.05). Moreover, posterior tooth loss was associated with dementia (HR = 2.23:1.27-3.91) and chewing ability with total immediate decline (OR = 1.80:1.04-3.13).

CONCLUSIONS

Posterior tooth and occlusal support loss significantly increases dementia risk. The impact of posterior occlusal support loss appears to be dose-dependent, and this effect is distinct from that of dentures. Dental healthcare services should be particularly attentive to the state of posterior dentition. Further studies exploring possible mechanisms are warranted.

New measure of functional tooth loss for successful Oral ageing: a cross-sectional study

BACKGROUND

This cross-sectional study evaluated the impacts of functional tooth loss on oral health-related quality of life (OHRQoL) among elderly people compared with the impacts of several common indicators of oral health. Additionally, the cut-off of functional tooth loss needed for a better OHRQoL was investigated to establish a new measure for successful oral ageing.

METHODS

Data from people aged 65-74 were extracted from the Fourth National Oral Health Survey in Sichuan, China. Functional tooth loss was defined as both natural tooth loss and nonfunctional teeth, such as third molars, residual roots, and removable dentures. The cut-offs of tooth loss were first identified as 12, based on the previous definition of functional dentition (≥20 natural teeth except the third molars), and 14, 16, or 18 for further investigation. OHRQoL was evaluated by the standardized Geriatric Oral Health Assessment Index (sGOHAI) score. Logistic regression was performed to estimate the impacts on OHRQoL. Additionally, subgroup analyses were conducted using the stratified chi-square test to explore the effect of functional tooth loss at each position.

RESULTS

The mean GOHAI score of the 744 participants was 48.25 ± 7.62. Elderly people who had lost ≤12 functional teeth had greater odds of reporting a higher sGOHAI score than those who had lost more functional teeth (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.05-2.11). No significant difference in the sGOHAI score was detected between people who had lost 13-16 functional teeth and those who had lost ≤12 functional teeth (0.61, 0.35-1.07). The loss of second premolars and first and second molars had great impacts on the sGOHAI score when ≤12 or ≤ 16 functional teeth had been lost.

CONCLUSIONS

Compared with natural tooth loss, functional dentition and occluding pairs, functional tooth loss can be a better indicator of OHRQoL in the elderly population. Sixteen remaining functional teeth seem to be sufficient to maintain good OHRQoL and successful oral ageing despite that number being previously acknowledged as ≥20 teeth.

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.

Association between masticatory performance and oral conditions in adults: A systematic review and meta-analysis

OBJECTIVES

To give an overview of the evidence on the associations between oral condition factors and masticatory performance of adults, and to evaluate the direction and level of the associations.

DATA/SOURCES

Medline (PubMed), Embase (Ovid) and CINAHL Plus (EBSCOhost) were searched up to May 2022 for cross-sectional studies on oral conditions and masticatory performance in adults. Methodological quality of the included studies was independently evaluated based on the Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between oral condition factors and masticatory performance were extracted. Meta-analysis was conducted on correlation coefficients.

STUDY SELECTION

Of the 8,035 records identified, 97 articles (88 studies) were included in the qualitative synthesis, and 18 studies were included in the meta-analyses. Among the oral condition factors that had associations with masticatory performance, the number of natural/remaining teeth or functional tooth pairs was reported by the largest number of studies, followed by perioral muscle status, dental prosthetic status, oral moisture status and periodontal status. Results of the meta-analyses showed that the positive association with the number of natural/remaining teeth was the strongest (pooled correlation coefficient: 0.51, 95%CI: 0.48 to 0.54), followed by the number of functional tooth pairs, maximum tongue force/pressure, while the association with the oral moisture status was the weakest.

CONCLUSIONS

Number of natural/remaining teeth and functional tooth pairs, perioral muscle status, oral moisture status, dental prosthetic status and periodontal status are the main oral condition factors influencing masticatory performance. Based on the limited evidence available, among these factors, the number of natural/remaining teeth has the strongest positive association, with a very low quality of evidence.

CLINICAL SIGNIFICANCE

This study provides valuable information on the oral condition factors associated with masticatory performance, which would be important for policymakers and clinical practitioners when deciding on the strategies for improving the masticatory performance of adults. This review highlights the need for standardization of measures and classifications of masticatory performance and oral conditions.

REGISTRATION

PROSPERO (registration number: CRD42021256824).

Long-term masticatory performance and ability following closed treatment for unilateral mandibular condylar neck or base fractures: a cross-sectional study

PURPOSE

The aim of this study was to find explanatory variables for objective and patient-reported long-term masticatory functioning in patients treated with maxillomandibular fixation for unilateral condylar neck or base fractures. These outcomes were compared to healthy control subjects.

METHODS

Patients treated between 1996 and 2013 were enrolled in the study. Objective measurements included the mixing ability test (MAT) for masticatory performance, and range of motion of the mandible. Patient-reported measurements included the mandibular function impairment questionnaire (MFIQ) for masticatory ability, and the visual analogue scale for pain. Healthy subjects were recruited between October 2018 and January 2019, and performed the MAT and MFIQ.

RESULTS

Twenty-one patients and 30 healthy subjects were included. The average follow-up period was 11.67 years. In adjusted regression analysis, the amount of occlusal units (OU) was associated with the MAT (P = 0.020; R² = 0.253) and MFIQ (P = 0.001, R² = 0.454). The MAT outcome was similar in both groups when correcting for OU (P = 0.001; R² = 0.201). The MFIQ was inferior in the patient group (P = 0.001).

CONCLUSION

Long-term masticatory performance was similar in patients with a history of condylar neck or base fracture and healthy subjects; however, masticatory ability was inferior in patients compared to healthy subjects.

The correlation between two occlusal analyzers for the measurement of bite force

Background

Occlusal force represents masticatory function. Using quantifiable occlusal indicators provides a more objective occlusal force evaluation. In the recent dental practice, digital methods such as the Dental Prescale II (DP2, GC Corp., Tokyo, Japan) and T-scan (T-Scan III v8; Tekscan Inc.) are commonly used in clinics to evaluate treatment outcomes. The T-scan provides the relative bite force (%) compared to the maximal bite force on individual teeth or the unilateral arch. The DP2 can quantify occlusal force, measured in newtons (N), on the half arch or the overall bite, but it is difficult to identify the bite force on an individual tooth. It is difficult to select a device that fulfils all the requirements to record occlusal force. This study aimed to investigate the association between the bite measured by the DPS2 and T-scan to determine whether the measured bite force is comparable through calculation.

Methods

A total of 80 healthy adults, including 41 women and 39 men with a mean age of 38.2, were requested to bite pressure sensitive film sheets ten minutes apart. Linear regression analysis was used to estimate the measured bite force by the DP2 and T-scan.

Results

There was a significant positive correlation between the occlusal force measured by the DP2 and T-scan (P < 0.01) when intercept was equal to zero as confounders were adjused. These results provided the comparability of the measured occlusal forces determined by the DP2 and T-scan.

Conclusion

The estimated bite force determined by DP2 and T-Scan is convertible using the linear equation from this study to increase the value for clinical applications. The estimated bite force from the two quantifiable occlusal indicators are comparable. The two commercially available quantifiable occlusal indicators can be fully adapted to all clinical requirements according to this result.

Duração da mastigação e da fase oral da deglutição em idosos com diferentes condições dentárias: análise clínica

RESUMO Objetivo: mensurar o tempo total da mastigação e da fase oral da deglutição em idosos saudáveis, considerando diferentes consistências alimentares, a presença de dentes naturais e o tipo de reabilitação oral protética, bem como realizar comparação entre as condições dentárias e as consistências. Métodos: estudo transversal com 57 idosos saudáveis, entre 60 e 82 anos, distribuídos em grupo dentado (D) (n=15) e grupos reabilitados: próteses parciais fixas ou removíveis em uma ou ambas as arcadas (PP) (n=15); prótese total removível maxilar e mandibular (PTR) (n=15); prótese total - prótese removível superior e prótese implanto-suportada inferior (PTIS) (n=12). O tempo de duração (segundos) da mastigação e da fase oral da deglutição foi medido nas consistências: sólida (pão francês), pudim (10 ml) e líquida (10 ml). Resultados: idosos dentados saudáveis apresentaram os intervalos: líquido=1,07±0,35 s; pudim=3,48±1,76 s; e sólido=27,88±7,11 s. Foram observadas diferenças estatisticamente significativas entre os grupos D e PTIS (p=0,0056) e entre D e PTR (p=0,0056) para líquido. Para todos os grupos, houve aumento estatisticamente significante entre as consistências líquida e sólida e entre pastosa e sólida (p<0,001). Conclusões: idosos dentados apresentaram menor tempo de fase oral da deglutição para líquidos do que idosos edêntulos totais reabilitados, mas não diferente dos idosos com prótese parcial. O tempo de mastigação e deglutição do alimento sólido foi maior que o das demais consistências, independente da condição dentária.

Association of Loss of Occlusal Pairs of Teeth with Sarcopenia in a Chinese Population of Community-Dwelling Elderly

OBJECTIVES

Tooth loss, which usually leads to malnutrition, is common in the elderly. However, limited information is available regarding its association with sarcopenia. This study aimed to investigate the relationship between loss of occlusal pairs of tooth and sarcopenia.

DESIGN

A cross-sectional retrospective study was performed.

SETTING

The elderly who participated in the National Basic Public Health Project in the Maigaoqiao Community Medical Center in Nanjing, Jiangsu Province, China.

PARTICIPANTS

A total of 2850 individuals aged ≥60 years were enrolled.

MEASUREMENTS

Sarcopenia was defined according to the criteria proposed by the Asian Working Group for Sarcopenia. A trained dentist assessed oral health status and counted the number of present teeth. Logistic regression analyses were performed to evaluate the association between the loss of occlusal pairs and sarcopenia.

RESULTS

The prevalence of sarcopenia was 7.1% (201/2850). Univariate logistic regression analysis showed that loss of occlusal pairs was associated with sarcopenia [anterior occlusal pairs (AOPs): odd ratio (OR) = 1.292, 95% confidence interval (CI) = 1.158-1.442; posterior occlusal pairs (POPs): OR = 1.147, 95% CI = 1.018-1.221]. Multivariate logistic regression analysis indicated that loss of POPs was still an independent risk for sarcopenia (OR = 1.108, 95% CI = 1.007-1.220) after adjustment for traditional confounders. Subgroup analysis showed that loss of POPs was more significantly linked to sarcopenia in those with advanced age (≥80years) (OR = 1.307, 95% CI = 1.116-1.532) and in females (OR = 1.165, 95%CI = 1.038-1.308). Compared to individuals with ≥5 occluding pairs of POPs, those with <5 occluding pairs of POPs had a higher incidence of sarcopenia.

CONCLUSIONS

Loss of POPs is associated with an increased risk of sarcopenia in the elderly in a Chinese population. Further research on the mechanism of the observed causal relationship is needed.

Duration of mastication and oral phase of swallowing in the elderly with different dental conditions: a clinical analysis

ABSTRACT Purpose: to measure the total time of mastication and oral phase of swallowing in healthy elderly people, considering different food consistency, the presence of natural teeth, and the type of prosthetic oral rehabilitation, as well to compare dental conditions and consistencies. Methods: a cross-sectional study with 57 healthy elderly people, aged between 60 and 82 years, divided into: dentate group (D) (n=15); and rehabilitated groups; PD: fixed or removable partial dentures in one or both arches (n=15); CRD: maxillary and mandibular complete removable dentures (n=15); ISCD: complete dentures - maxillary removable denture and mandibular implant-supported dentures (n=12). The duration time (seconds) of chewing and of the oral phase of swallowing was measured in the consistencies: solid (a roll slice), pudding (10 ml) and liquid (10 ml). Results: healthy dentate elderly subjects had the following intervals: liquid=1.07±0.35 s; pudding=3.48±1.76 s; and solid=27.88±7.11 s. Statistically significant differences were observed between the D and ISCD groups (p=0.0056) and between D and CRD (p=0.0056) for liquid. For all groups, there was a statistically significant increase between liquid and solid consistencies and between pasty and solid ones (p<0.001). Conclusions: the dentate elderly had shorter oral phase time of swallowing for liquids than the rehabilitated edentulous elderly, but not different from the elderly with partial dentures. Chewing and swallowing time for solid food was longer than that for the other consistencies, regardless of dental condition.

Mastication of crisp bread: Role of bread texture and structure on texture perception

Texture and structure of breads have been related to oral processing (FOP) performance and sensory perceptions, but moisture content might play a significant role. To evaluate the real impact of breads texture and structure, eliminating the possible role of moisture content, different toasted breads were investigated. Four commercial toasted sliced breads (white bread -WHB-, whole wheat bread -WWB-, non-added sugar bread -NSU-, non-added salt bread -NSA-) with similar ingredients but different texture and structure were selected. Texture and structure were instrumentally and sensory evaluated, besides FOP (total chewing time, number of chews until swallowing, chewing frequency, and mouthful) and bolus properties (moisture, saliva to bread ratio, hardness, adhesiveness, and cohesiveness). Toasted breads showed significant differences in hardness, cutting strength, and porosity, but panelists did not discriminate among them. FOP results indicated that harder samples (NSU) required longer mastication and a number of chews, and open crumb structures (WWB, WHB) with higher cell areas required less mastication. Also, bolus characteristics were affected by bread types, and bread with lower crumb hardness (WHB) produced more cohesive bolus. Having toasted breads allowed to eliminate possible influence of moisture content differences on sensory perception, mouthful and bolus water incorporation during mastication.