Pharyngeal Deposits Comprising Salivary Mucin in Tube-fed Elderly Patients: MUC2 and MUC7 Immunoreactivity.

Several investigators have reported that oral membranous and pharyngeal viscous deposits developed in bedridden elderly persons requiring nursing care without oral intake. Therefore, this study aimed to clarify the origin of viscous deposits on the pharyngeal mucosa based on characteristics of salivary and tracheal secretory mucin. The participants were 35 elderly people who required nursing care. All 46 collected specimens, including 30 intraoral and 16 pharyngeal specimens, were stained against specific mucins secreted from the respiratory tract and saliva gland using antibodies anti-MUC2 and anti-MUC7, respectively. Out of 35 participants, the intraoral membranous deposits and deposits on the pharyngeal mucosa developed in 17 (48.6%) and 10 persons (28.6%), respectively. The pharyngeal deposits developed in 58.8% of participants who developed intraoral deposits. All pathological specimens shared microscopic findings of various combinations of eosinophilic lamellar structure and a pale-basophilic amorphous substance. Immunohistochemically, both the 30 oral and the 16 pharyngeal specimens obtained from 17 participants were consistently positive for MUC7 but negative for MUC2. In conclusion, we clarified that the mucoid component of both oral and pharyngeal deposits comprised MUC7 salivary mucin, which revealed that both deposits originated from the oral cavity. This result strongly suggests that oral care is intimately related to oral and pharyngeal conditions.

Histopathological evaluation of oral membranous substance in bedridden elderly persons without oral intake in Japan.

OBJECTIVES: The aim of this study was to clarify by histopathological examination the origin of oral membranous substances deposited on the palate, tongue, buccal mucosa and teeth. BACKGROUND: Several investigators have reported membranous substances deposited in the mouths of bedridden elderly persons requiring nursing care without oral intake. However, the precise nature and origin of the substances are poorly understood. METHODS: Sixty-nine specimens were taken from the oral cavity of bedridden patients, that is, the palate, dorsum of the tongue, the cheek and teeth. Sections were stained with haematoxylin and eosin stain, alcian-blue and periodic acid-Schiff stain (AB-PAS) and antibodies for pankeratin (AE1AE3) and leukocyte common antigen (LCA). RESULTS: All specimens showed a film-like nature coloured from tan to white, accompanied by a mucous substance. Histologically, specimens of all sites had a similar feature of the combination of basophilic amorphous and eosinophilic lamellar features. The basophilic substance was positive for AB-PAS, and PAS-positive glycogen granules were also noted in the lamellar structure. Immunochemistry revealed various degrees of pankeratin positive substance and LCA-positive inflammatory cell infiltration. CONCLUSION: The oral membranous substance was composed of keratin and mucin with inflammation. These results suggest that the deposition of the oral membranous substance is a pathological condition or oral mucositis caused by dry mouth.

Tooth size in Chinese Oroqen ethnic minority of Inner Mongolia Autonomous Region.

The Oroqen are Tungusic hunters of the Amur River basin. We analyzed dental crown measurements from their dental impression models for anthropological characteristics. Sex difference was comparatively larger in the mesiodistal diameters. To examine the Mongoloids' distribution in the Northeast Asia, the data were compared with the results from the previous studies on other Northeast Asian races, using deviation diagrams, cluster analysis, and Multidimensional Scaling from Q-mode correlation coefficients. The Oroqen dentition is classified as Sinodont by the large surface area of their crowns. In the deviation diagram, the Oroqen beared an inverse proportion to the Aleutian Islanders, while showing little difference from the Okhotsk culture people, which suggested a close relation between the two races. The Q-mode correlation coefficients clustered the Oroqen into the Central Asian group with the Buriats and Mongolians. In the analysis of the distances transformed from Q-mode correlation coefficients, the Oroqen was delineated in the neighboring cluster to the Epi-Jomon/Satsumon and the Okhotsk people. It is inferred that the Central Asian group, spreading from Lake Baikal to the Amur basin have gradually mixed with the Baikal group, which later moved into the Amur region from the south. The mixing of the two groups could have been influenced by the geographical features of this area. It would be valuable to gather more data on the groups around the lower Amur region and to evaluate the distribution of the Mongoloids in Eastern Asia.

Expression of GAD67 and Dlx5 in the taste buds of mice genetically lacking Mash1.

It has been reported that a subset of type III taste cells express glutamate decarboxylase (GAD)67, which is a molecule that synthesizes gamma-aminobutyric acid (GABA), and that Mash1 could be a potential regulator of the development of GABAnergic neurons via Dlx transcription factors in the central nervous system. In this study, we investigated the expression of GAD67 and Dlx in the embryonic taste buds of the soft palate and circumvallate papilla using Mash1 knockout (KO)/GAD67-GFP knock-in mice. In the wild-type animal, a subset of type III taste cells contained GAD67 in the taste buds of the soft palate and the developing circumvallate papilla, whereas GAD67-expressing taste bud cells were missing from Mash1 KO mice. A subset of type III cells expressed mRNA for Dlx5 in the wild-type animals, whereas Dlx5-expressing cells were not evident in the apical part of the circumvallate papilla and taste buds in the soft palate of Mash1 KO mice. Our results suggest that Mash1 is required for the expression of GAD67 and Dlx5 in taste bud cells.

Factors affecting the formation of membranous substances in the palates of elderly persons requiring nursing care.

OBJECTIVE: To determine the causative factor behind the formation of membranous substances in the mouths of elderly patients requiring nursing care. BACKGROUND: Membranous substances are sometimes observed in the mouths of elderly persons requiring nursing care, and these can lead to bleeding, infection and asphyxiation. MATERIALS AND METHODS: In April 2007, samples were collected from 70 patients at C Hospital, Aichi Prefecture, Japan, who were 65 years or older (median age, 81.1 ± 7.7 years). Sixteen of the subjects were confirmed to have a membranous substance containing a keratin degeneration product that had been derived from stratified squamous epithelium. The samples were examined microscopically, and the presence of epithelial components was confirmed through immunohistochemical staining with anti-cytokeratin-1 antibodies. RESULTS: Decision tree analysis and logistic regression suggest that the leading contributors to the formation of the membranous substances were the method of ingesting nutrients, dryness of the tongue dorsum and open mouth. These three factors are related to elderly persons requiring nursing care with impaired oral cavity function, and it was suggested that dryness of the oral mucosa was the major factor behind the membrane formation.

Factors associated with dry mouth in dependent Japanese elderly.

OBJECTIVES: To identify factors associated with dry mouth. BACKGROUND: Dry mouth adversely affects oropharyngeal health, particularly in elderly, and can lead to pneumonia. A better understanding of the epidemiology of dry mouth is therefore important in improving treatment strategies and oral health in high-risk elderly patients. METHODS: We conducted a cross-sectional study involving 383 dependent Japanese elderly individuals (65-84 [n = 167] and ≥85 [n = 216] years) at eight long-term care facilities and hospitals. Thirty-four potential factors associated with dry mouth were examined by multiple logistic regression analysis. The primary outcome was dry mouth, as diagnosed by tongue dorsum moisture. RESULTS: We identified that body mass index and severity of physical disability were identified as a potential factors associated with dry mouth in the super-elderly (≥85 years) group, whereas severity of physical disability, outcome measurement time, high daily water consumption, mouth breathing, use of antidepressants and diuretics, and high frequency of daily brushing (≥2 times per day; Odds ratio: 5.56; 95% Confidence Interval: 1.52-20.00) were associated with dry mouth in the 65- to 84-year-old group. CONCLUSION: To our knowledge, this is the first study to identify a link between frequency of daily brushing and dry mouth and suggests that tooth brushing should be encouraged in high-risk dependent Japanese elderly (65-84 years), particularly those taking antidepressants and/or diuretics.

Palatal microbiota associated with membranous substances in older Japanese individuals undergoing tube feeding in long-term care: A cross-sectional study.

Objective: Tube feeders are prone to membranous substance formation on the palate, and those with membranous substances have a risk of fever, with the probable involvement of their oral bacteria. However, the palatal microbiota of those with membranous substances has not been elucidated. Therefore, we evaluated the differences in palatal microbiota between tube-fed individuals with and without membranous substances to clarify the microbiota. Materials and methods: This study included 19 participants aged 65 years who required tube feeding. The participants' characteristics were collected from nursing records and oral examinations. If membranous materials were found on the palate, a specimen was collected. Membranous substances were defined as keratotic degeneration observed under a microscope. Additionally, we performed a comprehensive microbiome analysis by extracting DNA from the samples and performing 16 S rRNA gene sequencing. Finally, we compared the participant demographics and oral microbiota between patients with and without membranous substances. Results: A total of 11 participants had membranous substances associated with "mouth dryness" (p < 0.001) and "constant mouth opening" (p = 0.020). Palatal microbiota differed between those with and without membranous substances. Among the bacteria with a relative abundance greater than 1.0%, the abundance of Streptococcus (p = 0.007), Fusobacterium (p = 0.041), Streptococcus agalactiae (p = 0.009), and Fusobacterium nucleatum subsp. vincentii (p = 0.026) was significantly higher in the membranous substance group than in the non-membranous substance group. Conclusions: The palatal microbiota of individuals undergoing tube feeding differed depending on the presence or absence of membranous substances. Membrane substance formation associated with dry mouth purportedly alters the palatal microbiota. Streptococcus, Fusobacterium, S. agalactiae, and F. nucleatum subsp. vincentii were more abundant in the oral microbiota of patients with membranous substances. Thus, preventing this formation may help in controlling the growth of these microbes.

New method for determining surface roughness of tongue.

OBJECTIVE: The degree of atrophy of the lingual papillae in elderly individuals was evaluated using a quantitative method. SUBJECTS AND METHODS: One hundred and eighty-two subjects living in nursing homes and 20 healthy adults as controls were studied. To express the degree of atrophy of the lingual papillae quantitatively, lingual surface roughness was determined by taking an impression with silicone dental material. Based on the impressions obtained from the elderly subjects, they were classified by three expert dentists into three groups: Normal, Smooth and Rough. The same determinations were also performed in the 20 healthy controls and compared with 38 of the elderly subjects who had agreement from all of the experts and without the presence of fissures (Normal, n = 6; Smooth, n = 12; Rough, n = 20). RESULTS: The roughness average value for the controls was 65.0 µm, while that for the elderly subjects in the Normal, Smooth and Rough groups was 73.9 µm, 42.2 µm and 94.1 µm, respectively, which were significantly different. CONCLUSION: The present results indicate that the present technique of obtaining an impression of the tongue surface is simple and reliable for routine evaluation and quantification of the degree of atrophy as well as morphology of the lingual papillae.

Association between oral, social, and physical frailty in community-dwelling older adults.

OBJECTIVES: Oral frailty (OF) has been shown to be a predictor of disability. Therefore, it is important to be able to identify factors associated with OF in order to prevent long-term dependence. The purpose of this study was to clarify the relationships between OF, social frailty (SF), and physical frailty (PF) in community-dwelling older adults, with the overarching aim of informing the future development of effective measures to prevent frailty. METHODS: Oral, physical, and social function, nutritional and psychological status, and medical history were examined in 682 community-dwelling individuals (267 men, 415 women) aged ≥ 65 years. Ordinal logistic regression analysis with SF and PF as independent variables was performed with pass analysis to determine the relationship between the different types of frailty. RESULTS: Logistic regression analysis revealed significant associations between OF and decline in social function, physical function, and nutritional status, and an increase in the number of medications used. Path analysis showed that SF was directly related to OF and that OF and SF were directly related to PF. CONCLUSIONS: These findings suggest that a decline in social function may directly influence a decline in oral and physical function. The results of this study provide initial evidence, that may guide the future development of measures that aim to prevent and manage OF.

The ethanol metabolite acetaldehyde induces water and salt intake via two distinct pathways in the central nervous system of rats.

The sensation of thirst experienced after heavy alcohol drinking is widely regarded as a consequence of ethanol (EtOH)-induced diuresis, but EtOH in high doses actually induces anti-diuresis. The present study was designed to investigate the introduction mechanism of water and salt intake after heavy alcohol drinking, focusing on action of acetaldehyde, a metabolite of EtOH and a toxic substance, using rats. The aldehyde dehydrogenase (ALDH) inhibitor cyanamide was used to mimic the effect of prolonged acetaldehyde exposure because acetaldehyde is quickly degraded by ALDH. Systemic administration of a high-dose of EtOH at 2.5 g/kg induced water and salt intake with anti-diuresis. Cyanamide enhanced the fluid intake following EtOH and acetaldehyde administration. Systemic administration of acetaldehyde with cyanamide suppressed blood pressure and increased plasma renin activity. Blockade of central angiotensin receptor AT1R suppressed the acetaldehyde-induced fluid intake and c-Fos expression in the circumventricular organs (CVOs), which form part of dipsogenic mechanism in the brain. In addition, central administration of acetaldehyde together with cyanamide selectively induced water but not salt intake without changes in blood pressure. In electrophysiological recordings from slice preparations, acetaldehyde specifically excited angiotensin-sensitive neurons in the CVO. These results suggest that acetaldehyde evokes the thirst sensation following heavy alcohol drinking, by two distinct and previously unsuspected mechanisms, independent of diuresis. First acetaldehyde indirectly activates AT1R in the dipsogenic centers via the peripheral renin-angiotensin system following the depressor response and induces both water and salt intake. Secondly acetaldehyde directly activates neurons in the dipsogenic centers and induces only water intake.

Perspectives on a new educational system for dental hygiene students in Japan.

The purpose of this article is to report changes to dental hygiene education in Japan and to evaluate the successful implementation of these changes in 2010. The legislative change that began in 2005 revised the length of education for dental hygiene students from two years to three or four years (the mandate was three years), which has led to a dramatic change in program curriculum. After a five-year moratorium, a new curriculum has been established for dental hygiene education in Japan. The new curriculum provides students the requisite knowledge to effectively perform the latest dental hygiene procedures. Although the change of the educational system from the present mandatory three-year to the new four-year programs poses many administrative problems, we believe this shift will ultimately provide a more thorough and in-depth education for students.

Salivary levels of hyaluronic acid in female patients with dry mouth compared with age-matched controls: a pilot study.

Little is known regarding the association between the level of hyaluronic acid (HA) in saliva and dry mouth status. The aim of this study was to evaluate the salivary levels of HA in female patients with dry mouth (perceived xerostomia and hyposalivation) and compare them with age-matched controls. We studied 46 females, and classified them into two groups based on perceived xerostomia and salivary flow rate, as well as a control group without symptoms. HA concentrations in unstimulated whole saliva were determined and a significant difference was found between the groups. The statistical association was stronger in patients (perceived xerostomia, normosalivation) administrated xerogenic drugs, while the HA levels in that group were significantly lower than those in the controls when converted to absolute amount of saliva per min. Within the limitations of the present study, patients with dry mouth had lower HA levels in saliva, which may serve as a marker of local dryness or oral mucosa lubrication.

Potential factors responsible for dryness of the dorsum of the tongue in elderly requiring care.

OBJECTIVE: This study explored potential factors in elderly requiring care that cause dryness of the dorsum of the tongue despite moisture retention in the sublingual mucosa. MATERIALS AND METHODS: Subjects were 224 elderly (mean age: 83.6 +/- 7.4 years) living in a nursing home and requiring individual care. Measurement of moisture of the dorsum of the tongue and sublingual mucosa was performed using a wetness tester (L-SALIVO) with a measurement time of 10 s. RESULTS: A significant difference in drying only of the dorsum of the tongue was noted depending on the degree of incapacity, level of consciousness, eating (oral ingestion or tube-feeding), and conversation. Multiple logistic regression identified the degree of incapacity in terms of eating (oral ingestion or tube-feeding) as a significant factor for dryness. The odds ratio for the degree of incapacity was 3.2 while that for eating was 11.226. CONCLUSION: Dry mouth of the dorsum of the tongue in elderly requiring care was associated with the degree of incapacity, tube feeding, and level of conversation.

Salivary levels of cortisol and chromogranin A in patients with dry mouth compared with age-matched controls.

OBJECTIVE: To evaluate the salivary levels of cortisol and chromogranin A (CgA) in patients with dry mouth (perceived xerostomia and hyposalivation) compared with age-matched controls. STUDY DESIGN: We studied 174 subjects, including those with dry mouth, classified into 2 subgroups based on perceived xerostomia and salivation, and those without (control subjects). The control subjects were patients at the same hospital and healthy volunteers. Cortisol and CgA levels in stimulated whole saliva were measured using ELISA kits. RESULTS: All subjects with dry mouth had significantly higher cortisol and CgA levels than the control subjects. The statistical associations remained significant when they were divided into the 2 subgroups, although somewhat weaker associations were observed. The influences of xerogenic drugs were found to be minimal on salivary flow rate and levels of cortisol and CgA. CONCLUSIONS: We found significant associations between salivary cortisol and CgA levels and symptoms of oral dryness and reduced salivary flow.

Usefulness of new wetness tester for diagnosis of dry mouth in disabled patients.

OBJECTIVES: The condition of dry mouth is an influential factor in the incidence of caries, periodontal disease, fungal infections, masticatory dysfunctions and denture function. Bedridden elderly and disabled persons often suffer from oral dryness and the aim of this study was to evaluate the usefulness of measuring the amount of moisture in the oral mucosa for clinical diagnosis of dry mouth in this group. SUBJECTS AND METHODS: The subjects were 20 elderly bedridden individuals, age range 65-89 years old, living in a nursing home and six healthy laboratory researchers, aged 20-46 years old, used as controls. Tongue dorsum moisture measurements were performed using a newly developed wetness tester (L-SALIVO), in which the wet portion was measured after 10 s. Further, clinical diagnosis of dry mouth was carried out using a clinical classification scale of the tongue mucosa (grade range, 0-3). RESULTS: It was possible to measure tongue dorsum moisture in all subjects with the wetness tester. The average moisture value was 0.1+/-0.2 mm in elderly subjects with a dry mouth grade of 2 (n = 8) or 3 (n = 12), while the average moisture value in the control subjects was 3.67+/-1.75 mm with a dry mouth grade of 0 (n = 4) or 1 (n = 2). Tester values and cliniical classification showed a positive co-relationship (r = 0.31, p < 0.05). CONCLUSIONS: Our results show that this new tester could be useful for evaluating oral dryness and diagnosing dry mouth.

High correlation between the bacterial species in denture plaque and pharyngeal microflora.

OBJECTIVES: The morbidity and mortality of the dependent elderly that result from aspiration pneumonia are recognized as a major geriatric health problem. Most cases of bacterial pneumonia are initiated following colonization or superinfection of the pharynx by pathogenic bacteria, followed by aspiration of pharyngeal contents. A recent study revealed that bacteria, that commonly cause respiratory infection, colonized the dentures of dependent elderly. This suggests that denture plaque may function as a reservoir of potential respiratory pathogens to facilitate colonization on the pharynx. The purpose of this study was to determine the possible correlation between denture and pharyngeal microflora. STUDY DESIGN: The denture and pharyngeal bacterial flora of 50 dependent elderly were examined, and the microorganisms identified by culturing. The agreement between the bacterial species in denture plaque and pharyngeal microflora was investigated using the Kappa method. RESULTS: The microorganism species on the dentures and pharyngeal mucosa of the subjects had an agreement rate of 68.5%. The agreement rate for each of the bacterial species of the dentures and pharynx was also demonstrated to be high. CONCLUSIONS: Dentures should be considered an important reservoir of organisations which could colonise the pharynx, and the importance of controlling denture plaque for the prevention of aspiration pneumonia cannot be overemphasized.