Poor Masticatory Capacity and Blood Biomarkers of Elevated Cardiovascular Disease Risk in the Community: The Paris Prospective Study III.

[Figure: see text].

Association between number of teeth and Alzheimer's disease using the National Database of Health Insurance Claims and Specific Health Checkups of Japan.

Associations of numbers of teeth present and of missing teeth with Alzheimer's disease were cross-sectionally analyzed using the National Database of Health Insurance Claims and Specific Health Checkups of Japan. Dental care claims data of patients aged 60 years or older diagnosed with periodontitis (n = 4,009,345) or missing teeth (n = 662,182) were used to obtain information about the numbers of teeth present and of missing teeth, respectively, and they were combined with medical care claims data including the diagnosis of Alzheimer's disease. Numbers of teeth present and of missing teeth excluding third molars were calculated using the dental formula in the claims for periodontitis and missing teeth, respectively, and categorized into three groups each. Percentages of subjects treated for Alzheimer's disease with 20-28, 10-19, and 1-9 teeth present were 1.95%, 3.87%, and 6.86%, respectively, in patients diagnosed as having periodontitis, and those treated for Alzheimer's disease with 1-13, 14-27, and 28 missing teeth were 2.67%, 5.51%, and 8.70%, respectively, in patients diagnosed as having missing teeth. Logistic regression models using treatment for Alzheimer's disease as an outcome variable and adjusting for age and sex showed that odds ratios (95% confidence intervals) for patients with 10-19 and 1-9 teeth (reference: 20-28 teeth) were 1.11 (1.10-1.13) and 1.34 (1.32-1.37), respectively, (p<0.001), in patients diagnosed as having periodontitis, and odds ratios (95% confidence intervals) for patients with 14-27 missing teeth and 28 missing teeth (reference: 1-13 missing teeth) were 1.40 (1.36-1.44) and 1.81 (1.74-1.89), respectively, (p<0.001), in patients diagnosed as having missing teeth. In conclusion, the results of the present study using Japanese dental claims data showed that older people visiting dental offices with fewer teeth present and a greater number of missing teeth are more likely to have Alzheimer's disease.

Causal Effect of Tooth Loss on Functional Capacity in Older Adults in England: A Natural Experiment.

BACKGROUND/OBJECTIVES: Tooth loss is associated with reduced functional capacity, but so far, there is no relevant causal evidence reported. We investigated the causal effect of tooth loss on the instrumental activities of daily living (IADL) among older adults in England. DESIGN: Natural experiment study with instrumental variable analysis. SETTING: The English Longitudinal Study of Aging (ELSA) combined with the participants' childhood exposure to water fluoride due to the community water fluoridation. PARTICIPANTS: Five thousand six hundred and thirty one adults in England born in 1945-1965 participated in the ELSA wave seven survey (conducted in 2014-2015; average age: 61.0 years, 44.6% men). MEASUREMENTS: The number of natural teeth predicted by the exogenous geographical and historical variation in exposure to water fluoride from age 5 to 20 years old (instrumental variable) was used as an exposure variable. The outcome, having any limitations in IADL (preparing a hot meal, shopping for groceries, making telephone calls, taking medications, doing work around the house or garden, or managing money), was assessed by self-reported questionnaires. RESULTS: Linear probability model with Two-Stage Least Squares estimation was fitted. Being exposed to fluoridated water was associated with having more natural teeth in later life (coefficient: 0.726; 95% confidence interval (CI) = 0.311, 1.142; F = 11.749). Retaining one more natural tooth reduced the probability of having a limitation in IADL by 3.1 percentage points (coefficient: -0.031; 95% CI = -0.060, -0.002). CONCLUSION: Preventing tooth loss maintains functional capacity among older adults in England. Given the high prevalence of tooth loss, this effect is considerable. Further research on the mechanism of the observed causal relationship is needed.

The Association between Number of Remaining Teeth and Maintenance of Successful Aging in Japanese Older People: A 9-Year Longitudinal Study.

With population aging, an increasing attention has been paid to quality of life rather than mere longevity. Now, it is urgently needed to clarify predictors of well-being in later life, i.e., "successful aging (SA)." The aim of this study is to investigate whether the number of remaining teeth impacts on maintenance of SA among Japanese older people. The present study was conducted in Tsurugaya district, a suburban area of Sendai, in northern Japan, and included older people aged ≥ 70 years who had met the criteria for SA at a 2003 baseline survey. At the baseline survey, dentists obtained data for the number of remaining teeth. We obtained information about Long-term Care Insurance certification, including the dates of incident functional disability and death between 2003 and 2012. Data pertaining to health-related quality of life (HRQOL) were collected at the 2003 baseline survey and the 2012 follow-up survey. Maintenance of SA was defined in terms of survival, disability-free status and high HRQOL in both 2003 and 2012. Among 450 participants, 108 (24.0%) were considered to have maintained a state of SA. When participants were classified into three groups according to previous studies, in comparison with participants who retained 0-9 teeth, the multivariate prevalence ratios (95% confidence intervals) were 1.39 (0.81-2.36) for those who retained 10-19 teeth and 1.58 (1.002-2.50) for those who retained ≥ 20 teeth (p trend = 0.046). The present results suggest that retaining ≥ 20 teeth is associated with maintenance of SA among Japanese older people.

The Effects of Dental Status and Chewing Efficiency on the Oral-Health-Related Quality of Life of Nursing-Home Residents.

OBJECTIVE: The aim of this study was to evaluate the effects of dental status and chewing efficiency on the oral-health-related quality of life (OHRQoL) of nursing-home residents. MATERIALS AND METHODS: The study was conducted in nine nursing homes. All eligible participants were included, and general and medical data, information about nutritional status and their dental and prosthetic status were collected. Chewing efficiency was assessed by means of a two-colour mixing-ability test. The simple count version of the Geriatric Oral Health Assessment Index (SC-GOHAI) was used to evaluate participants' OHRQoL, and the Mini-Mental State Examination to classify the presence of cognitive impairment. Univariate and multivariate regression models were used to analyse data. RESULTS: The mean age of the participants was 82.1 (± 9.8) years and most participants suffered from at least very mild cognitive impairment. OHRQoL for all participants (n = 143) and denture wearers only (n = 105) was substantially associated with the type of prosthesis, the presence of natural teeth, the number of functional occluding pairs and dental and denture-related (if applicable) treatment needs. Furthermore, in both model's univariate analysis showed that chewing efficiency also affected OHRQoL. In contrast, multivariate analysis of all participants revealed that only a higher number of functional occluding pairs (C: 0.250; p < 0.001), fewer dental treatment needs (C: -1.733; p = 0.019) and a better nutritional status (C: -1.298; p = 0.048) were relevant for better OHRQoL. For denture wearers, a higher number of functional occluding pairs (C: 0.192; p = 0.011), a better denture condition (C: -2.194; p= 0.003) and a higher body mass index (BMI) (C: 0.145; p = 0.006) were the main variables associated with better OHRQoL among participants. CONCLUSION: Good oral health and oral function, including chewing efficiency, are associated with a high OHRQoL of nursing-home residents. However, few dental treatment needs, well-fitting dentures without treatment needs and a high number of functional occluding pairs seem to be the principal variables for an acceptable OHRQoL of nursing-home residents.

Surgical solutions to orofacial problems.

BACKGROUND: Orofacial problems present frequently to primary care providers. Many of these problems have a surgical solution. Some may require minor procedures, while others require major maxillofacial surgery. OBJECTIVE: The purpose of this article is to illustrate how some common orofacial presentations can be investigated and solutions found in conjunction with oral and maxillofacial surgeons. DISCUSSION: This article outlines a method of approach for some of the issues with which patients present to their primary healthcare provider that may be resolved using skills and techniques of maxillofacial surgery.

A novel nonsense variant in SLC24A4 causing a rare form of amelogenesis imperfecta in a Pakistani family.

BACKGROUND: Amelogenesis imperfecta (AI) is a highly heterogeneous group of hereditary developmental abnormalities which mainly affects the dental enamel during tooth development in terms of its thickness, structure, and composition. It appears both in syndromic as well as non-syndromic forms. In the affected individuals, the enamel is usually thin, soft, rough, brittle, pitted, chipped, and abraded, having reduced functional ability and aesthetics. It leads to severe complications in the patient, like early tooth loss, severe discomfort, pain, dental caries, chewing difficulties, and discoloration of teeth from yellow to yellowish-brown or creamy type. The study aimed to identify the disease-causing variant in a consanguineous family. METHODS: We recruited a consanguineous Pashtun family of Pakistani origin. Exome sequencing analysis was followed by Sanger sequencing to identify the pathogenic variant in this family. RESULTS: Clinical analysis revealed hypomaturation AI having generalized yellow-brown or creamy type of discoloration in affected members. We identified a novel nonsense sequence variant c.1192C > T (p.Gln398*) in exon-12 of SLC24A4 by using exome sequencing. Later, its co-segregation within the family was confirmed by Sanger sequencing. The human gene mutation database (HGMD, 2019) has a record of five pathogenic variants in SLC24A4, causing AI phenotype. CONCLUSION: This nonsense sequence variant c.1192C > T (p.Gln398*) is the sixth disease-causing variant in SLC24A4, which extends its mutation spectrum and confirms the role of this gene in the morphogenesis of human tooth enamel. The identified variant highlights the critical role of SLC24A4 in causing a rare AI type in humans.

Effects of self-assessed chewing ability, tooth loss and serum albumin on mortality in 80-year-old individuals: a 20-year follow-up study.

BACKGROUND: The association between dental status and mortality in community-dwelling older adults has been documented by several studies. The aim of this study was to analyze the contribution of self-assessed chewing ability, number of remaining teeth and serum albumin levels to mortality and the interactions between the three factors. METHODS: A 20-year follow-up study was conducted with 666 subjects aged 80 years (from 1996 to 2017) who resided in the 8 areas served by one health center in Iwate Prefecture. Health check-ups including physical fitness measurements were conducted at a meeting place or gymnasium. Medical interview and blood sampling were conducted by physician. Oral examination was examined by dentist. The number of remaining teeth, serum albumin levels, and self-assessed chewing ability were used as predictors of mortality. RESULTS: Among the 608 subjects (233 men and 375 women) included in this study, only 12 subjects (1.97%) survived after 20 years of follow-up. For men, dental status and serum levels of albumin were significantly associated with mortality. The hazard ratios of self-assessed chewing ability calculated by item response theory analysis and the inability to chew at least one food adjusted for serum albumin and tooth conditions were statistically significant in men. When adjusted by health status evaluated by blood tests, self-assessed chewing ability was statistically significant in men. According to path analysis, self-assessed chewing ability and serum albumin independently affected mortality in men. CONCLUSION: Masticatory dysfunction may be an important risk factor for mortality in men, even though it was self-assessed. Retaining chewing ability might be a useful predictor of longevity in older male adults.

Tooth loss early in life induces hippocampal morphology remodeling in senescence-accelerated mouse prone 8 (SAMP8) mice.

Long-term tooth loss is associated with the suppression of hippocampal neurogenesis and impairment of hippocampus-dependent cognition with aging. The morphologic basis of the hippocampal alterations, however, remains unclear. In the present study, we investigated whether tooth loss early in life affects the hippocampal ultrastructure in senescence-accelerated mouse prone 8 (SAMP8) mice, using transmission electron microscopy. Male SAMP8 mice were randomized into control or tooth-loss groups. All maxillary molar teeth were removed at 1 month of age. Hippocampal morphologic alterations were evaluated at 9 months of age. Tooth loss early in life induced mitochondrial damage and lipofuscin accumulation in the hippocampal neurons. A thinner myelin sheath and decreased postsynaptic density length were also observed. Our results revealed that tooth loss early in life may lead to hippocampal ultrastructure remodeling and subsequent hippocampus-dependent cognitive impairment in SAMP8 mice with aging.

Prenatal Development of the Humpback Whale: Growth Rate, Tooth Loss and Skull Shape Changes in an Evolutionary Framework.

Extant baleen whales (Mysticeti) share a distinct suite of extreme and unique adaptations to perform bulk filter feeding, such as a long, arched skull, and mandible and the complete loss of adult dentition in favor of baleen plates. However, mysticetes still develop tooth germs during ontogeny. In the fossil record, multiple groups document the transition from ancestral raptorial feeding to filter feeding. Fetal specimens give us an extraordinary opportunity to observe when and how this macroevolutionary transition occurs during gestation. We used iodine-enhanced and traditional CT scanning to visualize the internal anatomy of five fetuses of humpback whale representing the first two-thirds of gestation, and we combine these data with previously published reports to provide the first comprehensive qualitative description of the sequence of developmental changes that characterize the skull and dentition. We also use quantitative methods based on 3D landmarks to investigate the shape changes in the fetuses in relation to a juvenile cranial morphology. We found similarities in the ossification patterns of the humpback and other cetaceans (dolphins), but there appear to be major differences when comparing them to terrestrial artiodactyls. As for the tooth germs, this developmental sequence confirms that the tooth-to-baleen transition occurs in the last one-third of gestation. Analysis of cranial shape development revealed a progressive elongation of the rostrum and a resulting posterior movement of the nasals relative to the braincase. Future work will involve acquisition of data from other species to complete our documentation of the teeth-to-baleen transition. Anat Rec, 2018. © 2018 American Association for Anatomy.

Hypophosphatasia in Adults: Clinical Spectrum and Its Association With Genetics and Metabolic Substrates.

BACKGROUND: Hypophosphatasia (HPP) is a rare metabolic bone disorder caused by mutations in the alkaline phosphatase (ALPL) gene, and characterized by low circulating alkaline phosphatase (ALP) levels and bone, muscle, dental and systemic manifestations. In this case series we investigate the clinical spectrum, genetic and biochemical profile of adult HPP patients from the University Hospitals Leuven, Belgium. METHODOLOGY: Adults with HPP were identified through medical record review. Inclusion criteria were: (1) age ≥ 16 yr; (2) consecutively low ALP levels not explained by secondary causes; (3) one or more of the following supporting criteria: biochemical evidence of elevated enzyme substrates; subtrochanteric fractures, metatarsal fractures or other typical clinical features; family history of HPP; a known or likely pathogenic ALPL mutation. RESULTS: Nineteen patients met our inclusion criteria (n = 2 infantile, n = 6 childhood, n = 10 adult-onset HPP and one asymptomatic carrier). Fractures and dental abnormalities were the most reported symptoms. Fatigue was reported in n = 7/19 patients (37%), three of which had previously been misdiagnosed as having chronic fatigue syndrome and/or fibromyalgia. Empirical pyridoxine therapy in four patients (without seizures) did not provide symptomatic relief. N = 7/19 patients (37%) were inappropriately treated or planned to be treated with antiresorptive treatment. Two patients developed atypical femoral fractures following exposure to bisphosphonates and/or denosumab. Patients detected by screening were less severely affected, while patients with homozygous or compound heterozygous mutations had the most severe symptoms, significantly lower circulating ALP levels (p = 0.013) and significantly higher pyridoxal-5'-phosphate (p = 0.0018) and urinary phosphoethanolamine (p = 0.0001) concentrations. CONCLUSIONS: Screening may detect mainly less severely affected individuals, which may nevertheless avoid misdiagnosis and inappropriate antiresorptive drug exposure. Patients with biallelic mutations had more severe symptoms, significantly lower ALP and higher substrate levels. Whether the latter finding has implications for the classification and treatment of HPP should be investigated further in larger cohorts.

Effect of tooth loss and nutritional status on outcomes after ischemic stroke.

OBJECTIVES: Tooth loss, closely associated with malnutrition, increases the risk for cardiovascular disease. The aim of this study was to examine the link between tooth loss, nutritional status, and stroke outcomes. METHODS: We retrospectively analyzed 195 consecutive patients with acute ischemic stroke who were evaluated for tooth loss. Tooth loss was classified as mild or severe. Nutritional status was evaluated using the Controlling Nutritional Status (CONUT) score. A poor neurologic outcome was defined as a score of 3 to 6 on the modified Rankin Scale at 3 mo post-stroke onset; a score of 0 to 2 was defined as a good outcome. RESULTS: A significant correlation was observed between tooth loss and the CONUT score at admission (ρ = 0.156; P = 0.034). Patients with poor outcomes had higher CONUT scores (P < 0.001) and a greater frequency of severe tooth loss (P = 0.025). On multivariate analysis, severe tooth loss (odds ratio [OR], 3.93; 95% confidence interval [CI], 1.31-11.8) and the CONUT score (OR, 1.33; 95% CI, 1.02-1.74) were independently associated with poor stroke outcomes. CONCLUSIONS: Nutritional status was associated with tooth loss among patients with acute ischemic stroke. Severe tooth loss and a higher CONUT score were independently associated with poor stroke outcomes.

Updates from the Evidence Base Examining Association between Periodontal Disease and Type 2 Diabetes Mellitus: Current Status and Clinical Relevance.

PURPOSE OF THE REVIEW: Epidemiological surveillance documents an escalating epidemic prevalence of both type 2 diabetes (T2DM) and periodontal disease (PD). The principal goals of this review are to: 1) re-examine the clinical significance of associations between PD and T2DM, based on strength of collective evidence as determined by systematic review and meta-analysis, and 2) review findings of the systematic reviews and meta-analyses in light of the current understanding of PD-associated pathophysiology and intersection with T2DM pathophysiology. RECENT FINDINGS: Tooth loss predicts risk for chronic disease and mortality. PD is significantly associated with complications of diabetes, including retinopathy. Based on systematic reviews and meta-analyses, the adjunctive use of certain antibiotics enhances non-surgical periodontal treatment (NSPT) in patients with T2DM. Systematic reviews and meta-analyses support NSPT efficacy in achieving metabolic control. Systematic reviews and meta-analyses support the association between PD and T2DM, albeit the effect size may be modest. PD-T2DM interactions have important clinical implications.

Chewing ability and desaturation during chewing in patients with COPD.

Chewing ability is essential to maintain nutrition status and can be associated with oral conditions, sarcopenia, and lung function in patients with chronic obstructive pulmonary disease (COPD). Herein, our pilot study investigated the chewing ability and degree of desaturation during chewing in patients with COPD (n = 41) and control subjects (n = 22). Subjects chewed a color-changing chewing gum for 1 minute and chewing ability was assessed by the color of the chewed gum, which was scored from 1 (very poor) to 5 (very good). Arterial oxygen saturation (SpO2) was monitored using a pulse oximeter and the difference in SpO2 was determined by comparison between before and during chewing. The mean color score of the chewed gum was lower in the COPD group than in the control group (3.1±0.7 vs 4.2±0.9, p<0.0001). Muscle mass loss (p<0.05), <20 remaining teeth (p<0.005), and COPD (p<0.001) were risk factors for poor chewing ability. The mean SpO2 decreased by 0.78±1.46% during gum chewing for 1 min. The mean SpO2 during gum chewing (95.1±2.4%) was lower than before gum chewing (95.9±1.7%) (p<0.05). The reduction of SpO2 was greater in COPD patients who had fewer remaining teeth (p<0.05). COPD patients with SpO2 reduction >4% during the 6-minute walk test showed greater reduction during gum chewing (p<0.05). Our results suggest that COPD patients with fewer remaining teeth exhibit poor chewing ability and greater desaturation during chewing.

An investigation of the bidirectional link between osteoporosis and periodontitis.

This study investigated whether periodontitis affects systemic bone status and whether FRAX® is a screening tool for periodontal disease in elderly women. The findings showed that bone density was not influenced by periodontitis and highlighted that women with FRAX® score above the intervention threshold had greater chance to present severe periodontitis. PURPOSE: This study investigated whether periodontal disease is a predictor for systemic bone loss among elderly women. The utilization of FRAX® as a screening tool for severe periodontitis was also evaluated in this population. METHODS: Current bone mineral density (BMD) for lumbar spine and proximal femur was used as an indicator of "bone status." Number of interdental sites with severe clinical attachment loss, frequency of bleeding on probing, and percentage of tooth loss due to periodontitis represented "periodontal disease" that was tested as a predictor of bone loss in a structural equation modeling analysis involving 110 participants. The intake of antiosteoporosis medication was considered in the analysis. Four other different criteria for periodontitis classification were also tested. FRAX® for major fracture was calculated without BMD, and with intervention threshold set by age. Longitudinally, BMD changes up to 10 years were also obtained and checked for possible association with periodontitis. RESULTS: Periodontal disease was not a predictor for worse systemic bone status according to the different periodontal disease classifications, and was not associated with BMD changes. Antiosteoporosis medication directly predicted periodontal disease and systemic bone status. Women with FRAX® score above the intervention threshold had higher chance for periodontitis in more advanced stages: III/IV (OR = 1.13, 95% CI [1.04 to 1.22], p = 0.03). CONCLUSION: Periodontal disease did not constitute a predictor for reduced systemic bone density in the studied population of elderly women. On the other hand, FRAX® demonstrated to be a useful tool to suggest periodontal evaluation. Antiresorptive medication showed benefits on periodontal and bone status.

Relationship between tooth loss, low masticatory ability, and nutritional indices in the elderly: a cross-sectional study.

BACKGROUND: Low masticatory ability and the resulting decrease in intake of masticable foods can result in undernutrition. The present study investigated the relationship between tooth loss, low masticatory ability, and nutritional indices in the elderly. METHODS: The data analyzed in this study were retrieved from the baseline data of the 2007 Fujiwara-kyo study, a prospective cohort study of community-dwelling elderly individuals. Subjects included 1591 men and 1543 women, both with a median age of 71 years. The maximum occlusal force was measured as an objective index of masticatory ability. Foods were divided into five groups based on hardness: Group 1 (bananas, etc.), 0.53 kg; Group 2 (boiled rice, etc.), 1.22 kg; Group 3 (raisins, etc.), 2.93 kg; Group 4 (raw carrots, etc.), 4.38 kg; and Group 5 (beef jerky), 6.56 kg. To obtain a subjective index of masticatory ability, a questionnaire-based survey was conducted to determine whether subjects could masticate foods within each group. As nutritional indices, serum albumin levels and body mass index (BMI) data were used. RESULTS: The median number of teeth was 21. The proportion of subjects for whom all five food groups were masticable showed a significant decrease in the number of teeth in both males and females. Logistic regression analysis showed that, after adjustment for confounders, no significant relationships were observed between the number of teeth and the masticatory ability with nutritional indices in males. In females, a maximum occlusal force of 100 to 300 N (OR = 1.65; 95% CI = 1.06-2.55) or less than 100 N (OR = 1.95; 95% CI = 1.15-3.31) showed a significant correlation with serum albumin levels below 4.4 g/dL (reference: 500 N or more). In addition, the masticability of all five food groups showed a significant correlation with BMI < 21.0 kg/m2 (OR = 0.62; 95% CI = 0.46-0.85) in females. CONCLUSIONS: A low number of teeth was associated with low masticatory ability in both males and females. Low masticatory ability was associated with low plasma albumin levels and low BMI in females. Not smoking, maintaining grip strength, preventing cancer, and masticatory ability are important for preventing undernutrition.

Prospective cohort of adult oral health in Piracicaba, SP, Brazil.

OBJECTIVE: To describe the methodological aspects of a Prospective Cohort Study of adult oral health in Piracicaba, Brazil. RESULTS: This Prospective Cohort Study evaluated adults (20-64 years old) between the years of 2011 and 2015, in Piracicaba, São Paulo, Brazil. The main objective was to evaluate the risk factors for tooth loss in adults. Data were collected at households and selected via probabilistic sampling, through clinical examination of caries, considering as variables the decayed, missing and filled permanent teeth index, need for caries treatment, periodontal disease (Community Periodontal Index and Periodontal Attachment Loss), use and need for dental prosthesis, and presence of visible biofilm. A questionnaire about demographic, socioeconomic and health habits, use of dental services, self-perceived quality of life (Oral Health Impact Profile-14) and health literacy (14-item Health Literacy Scale) was also employed. In 2011, 248 adults participated, and in 2015, 143 (follow-up rate = 57.7%). Despite the follow-up sample loss, most sociodemographic characteristics remained in the participant sample: for example, women (72.0%) (p = 0.534), family income between R$545,00 and R$1090,00 (63.9%) (p = 0.920), above 11 years of education (53.1%) (p = 0.200) and belonging to middle class (67.1%) (p = 0.909).

The concept of exposure when selecting comparison groups for determining individual susceptibility to addiction to cigarette smoking.

Smoking is a leading cause of preventable death. The effect of tobacco is even more contundent in people with mental illness and, in general, cigarette smoking addiction is influenced by genetic factors. The opioid system is involved in the mesolimbic reward system, which is of great importance in addictive behaviors, such as smoking and is influenced by genes such as the OPRM1. The aim of this study was to evaluate if selecting a comparison group that include light smokers versus people that never smoked impacts the results of genetic association studies. In addition, to evaluate the genetic association in different groups of smokers by analyzing independent covariates such as mental illness and clinical dental data. All subjects were participants of the Dental Registry and DNA Repository project. Genotyping was carried out using TaqMan chemistry for two markers in OPRM1 (rs553202 and rs7755635). Logistic regression analyses were performed as implemented in PLINK. The established value for alpha was 5%, and the Hardy-Weinberg equilibrium was evaluated by the chi-square test with one degree of freedom for each marker. 1,897 patients were included, which were allocated to eight distinct groups, according to the frequency and quantity of cigarettes smoked and mental illness status. There was no significant association between the two markers in OPRM1 and smoking. When mental illness and dental clinical data (tooth loss, dental caries, and periodontitis) were used as covariates, there were associations between heavy smoking and OPRM1, when non-smokers were used as comparison. We did not have diet or microbiome data to consider for these dental analyses and suggest that these kinds of data should be always incorporated in the future. Significant results were found only when the covariables mental illness and oral clinical data were added to the analysis.

Relationship between functional masticatory units and cognitive impairment in elderly persons.

BACKGROUND: Studies on the elderly have reported that the risk of cognitive impairment is affected by chewing difficulty. OBJECTIVE: To determine whether there is a relationship between the number of pairs of antagonist teeth that come into contact when the mouth is closed (functional masticatory units [FMUs]) and the level of cognitive impairment. METHODS: We conducted a cross-sectional observational study with 502 institutionalised White individuals older than 65 years, living in the northwest of Spain and Portugal. Through a direct visual inspection, we recorded the number of FMUs. Cognitive impairment was assessed by applying the Mini-Cognitive Examination (MCE), a test derived from the Mini-Mental State Examination. To describe the statistical relationship between the FMUs and the MCE values, a generalised linear model (GLM) was applied. We assessed the GLM predictive capacity for detecting cognitive impairment (MCE ≤23) in a new study group consisting of 156 elderly individuals. RESULTS: A large number of FMUs was significantly associated with a lower probability of cognitive impairment, regardless of the nature of the contact and its location (explained deviance, 30.1%). The model's discriminatory capacity for cognitive impairment based on the FMUs was "good" (0.820). The model's predictive capacity for cognitive impairment was "acceptable" (sensitivity, 0.786; positive predictive value, 0.900; accuracy, 0.729). CONCLUSION: In White, elderly institutionalised individuals, the absolute number of FMUs is significantly related to their MCE scores.

Association between tongue muscle strength and masticatory muscle strength.

BACKGROUND: The tongue is responsible for compressing food against the palate and squeezing it into the pharynx during the oral preparatory phase of swallowing. Tongue pressure (TP), an indicator of tongue muscle strength, has been observed to decline with age; maximum occlusal force (MOF), an indicator of chewing ability, is correlated with TP. However, no study has investigated the relationship between TP and MOF. OBJECTIVE: To investigate the correlation between TP and MOF according to age in healthy individuals. METHODS: We retrospectively collected handgrip strength (HGS), body mass index (BMI), TP, MOF and tooth loss data for 785 healthy participants (305 men, 480 women). All subjects had either unilateral or bilateral occlusal support, regardless of the presence of dentures or natural teeth. The participants were divided into two groups: an adult (20s-50s, n = 497) group and an elderly (60s-80s, n = 288) group. Multivariate linear regression analysis was performed to determine significant independent variables associated with TP in both groups. RESULTS: Multivariate analysis revealed that TP was significantly associated with age (ß = -0.153), BMI (ß = 0.205), HGS (ß = 0.298) and MOF (ß = 0.239) in the adult group (all P < 0.001) and with age (ß = -0.266, P < 0.001), BMI (ß = 0.160, P = 0.005), MOF (ß = 0.217, P = 0.001) and tooth loss (ß = 0.156, P = 0.011) in the elderly group. CONCLUSIONS: As age and MOF are each associated with TP in both elderly and adult patients, age-related TP decline can be prevented with routine lingual exercises, even before the onset of old age. Additionally, MOF deterioration may indicate a decline in TP for elderly.