Association Between Tongue Pressure and Prevalence of Mild Cognitive Impairment in Japan.

OBJECTIVE: Although it has been suggested that a decline in oral function is one of the potential risk factors affecting mild cognitive impairment (MCI), evidence is insufficient to draw clear conclusions. This Japanese cross-sectional study examined the association between tongue pressure (TP) and MCI in middle-aged and older adults aged 36-84 years. METHODS: Study participants were 1019 (368 men and 651 women). TP was evaluated using a TP measurement device. The maximum value of three measurements was used for analysis. MCI was defined as being present if a participant had a Japanese version of the Montreal Cognitive Assessment score of <26. Adjustment was made for age, smoking status, alcohol consumption, leisure-time physical activity, body mass index, hypertension, dyslipidemia, diabetes mellitus, history of depression, number of teeth, employment, education, and household income. RESULTS: The prevalence of MCI was 45.3%. Among women, compared with the lowest tertile of TP, the second and highest tertiles were significantly associated with a lower prevalence of MCI with a clear dose-response relationship; the adjusted odds ratio (95% confidence intervals) in the second and highest tertiles of TP were 0.54 (0.36-0.83) and 0.55 (0.36-0.84), respectively (p for trend = 0.005). In contrast, no statistically significant association was observed between TP and the prevalence of MCI among men. CONCLUSIONS: Our findings suggest that higher TP might be inversely associated with the prevalence of MCI in middle-aged and older Japanese women.

Patient-reported oral function and psychological well-being outcomes of papillary thyroid cancer patients (PTC) after surgery: a cross-sectional study.

BACKGROUND: This study was performed to evaluate the differences in oral function and psychological well-being between patients with PTC after the gasless transoral endoscopic thyroidectomy vestibular approach (gasless-TOETVA) and patients with PTC after open surgery. METHODS: PTC patients who underwent radical surgery from May 2021 to August 2022 were included in this study. Postoperative data on oral function and psychological well-being, including the Oral Health Impact profile-14 (OHIP-14) and State-Trait Anxiety Inventory Form Y, were collected and analyzed. RESULTS: 212 patients were included in the analysis. Among them, 102 patients who received gasless-TOETVA were assigned to the gasless-TOETVA group, while the remaining 110 patients who underwent open surgery were categorized as the open group. Although the OHIP-14 score in the gasless-TOETVA group was higher than that of the open group from 6 months to 1 year after surgery (p = 0.012), the difference in OHIP-14 scores between the two groups disappeared 1 year after surgery (p = 0.155). There were no differences between the gasless-TOETVA group and the open group in state-anxiety scores. However, the gasless-TOETVA group had significantly lower trait-anxiety scores than the open group at all follow-up time periods. Furthermore, within the gasless-TOETVA group, patients who were more than 1 year post-surgery showed significantly increased trait-anxiety scores compared to those of patients who were less than 1 year post-surgery (Δ = 3.4; p = 0.032). In contrast, the open group showed a decreasing trend in trait-anxiety scores, but there was no statistically significant difference between patients who had surgery less than 1 year ago and those who had surgery more than 1 year ago (Δ = - 2.2; p = 0.094). CONCLUSION: Gasless TOETVA had a temporary impact on oral function, but it did not alleviate the state of anxiety. Furthermore, we observed a significant increase in trait-anxiety scores among PTC patients who underwent gasless-TOETVA after 1 year.

Association between masticatory function, frailty, and functional disability: an observational study.

BACKGROUND: Increase in functional disability in aging societies is an international medical and public health issue. Masticatory function may be a potential risk factor for functional disability, but the role of frailty in the association has not been clarified. METHODS: Forty thousand five hundred sixty-two community-dwelling older adults aged 65 years and over who were insured by public health insurance as of April 2018 were followed up for a median of 3.0 years. Masticatory function was categorized as good, moderate, or poor based on a self-reported questionnaire. The development of functional disability was defined as a new certification of the need for long-term care. A Cox proportional hazards model was used to calculate hazard ratios (HRs) and their 95% confidence intervals (CIs). RESULTS: During the follow-up period, 1,397 individuals experienced functional disability. After adjusting for age, sex, comorbidities, medical history, and lifestyle behaviors, the HR for incident functional disability was significantly higher in the moderate and poor groups compared to the good group (moderate, HR 1.21 [95% CI, 1.07-1.37]; poor, HR 1.64 [95% CI, 1.03-2.62]). However, after additional adjustment for frailty-related factors-namely, underweight, regular exercise, and gait speed-the association was attenuated in both the moderate group (HR 1.06 [95% CI, 0.94-1.21]) and the poor group (HR 1.51 [95% CI, 0.94-2.41]). CONCLUSIONS: Masticatory dysfunction was significantly associated with incident functional disability in a community-dwelling older Japanese population. Our findings suggest that masticatory dysfunction may be a surrogate of frailty rather than a direct cause of functional disability.

Relationships between oral function, dietary intake and nutritional status in older adults aged 75 years and above: a cross-sectional study.

BACKGROUND: Malnutrition is related to impaired oral health and function that causes poor dietary intake, declining the general health of older adults. The role of dietary intake in the association between oral function and nutritional status of Chinese older adults (aged 75 and above) was examined in this cross-sectional study. METHODS: Through the randomized cluster sampling method, 267 older adults living in rural areas of Qingdao, Shandong (aged 81.4 ± 4.3, 75-94 years) were chosen as the primary research participants. A Mini Nutritional Assessment - Short Form was used to determine nutritional status, and Food Frequency Questionnaire and 24-hour Food Intake Recall were used to assess dietary intake. The oral function was evaluated by analyzing the teeth, oral problems, bite force, tongue pressure, lip sealing pressure, chewing function questionnaire, whole saliva flow rate, 10-Item Eating Assessment Tool, and water swallow test. RESULTS: Based on the MNA-SF score, it was divided into a well-nourished group and a malnutrition group, with the malnutrition group comprising 40.6% of participants. The participants in the malnutrition group showed a higher rate of xerostomia, lower bite force, tongue pressure, and lip sealing pressure, and higher Chewing Function Questionnaire and 10-Item Eating Assessment Tool scores. Furthermore, their plant fat, iron, cereals and potatoes, vegetables, fruits, and seafood intake were relatively low. The regression model indicated that exercise frequency, stroke, chewing and swallowing function, intake of vegetables and fruits were risk factors for nutritional status of older adults. CONCLUSION: Malnutrition was relatively common among the Chinese older adults aged 75 and above, and it was significantly correlated with exercise frequency, stroke, chewing and swallowing function, and intake of vegetables and fruits. Therefore, nutrition management should be carried out under the understanding and guidance of the oral function and dietary intake of the older adults.

Relationship between maximal isometric tongue pressure and limit of fracture force of gels in tongue squeezing.

BACKGROUND: There is no clear objective indicator for selecting soft foods that are required for food bolus formation in older people with impaired oral function. OBJECTIVE: This study aimed to investigate the relationship between maximal isometric tongue pressure (MITP) and the mechanical properties of gels that can be crushed by the tongue. METHODS: This study included 65 healthy participants aged 22-96 (young group; 15 males, 15 females; older dentate group; 7 males, 8 females; older edentulous group; 10 males, 10 females). MITP was measured by the balloon-probe device. Agar gel with 10 different kinds of fracture force from 10N to 100N was used. The limit of fracture force of gels (LFFG) that were crushed by the tongue was measured by the up-and-down method. In the older edentulous group, two items were measured with and without dentures. Spearman's rank correlation coefficient was used to evaluate the relationship between MITP and LFFG in each group (p < .05). RESULTS: There were positive correlations between MITP and LFFG in all groups (overall groups: rs = .66, young group: rs = .46, older dentate group: rs = .61, older edentulous group with dentures: rs = .60, older edentulous group without dentures: rs = .47). CONCLUSION: MITP and LFFG were positively correlated in young, older dentate and older edentulous groups, suggesting that MITP has the potential to be an objective indicator of the range of mechanical properties of soft food that can be crushed by the tongue.

Can oral diadochokinesis be used as an assessment tool of oral function in older adults requiring care in nursing home?

BACKGROUND: Oral diadochokinesis (OD) test is an articulation test that analyses fine movements of the lips, cheeks and tongue. It is difficult to perform the test accurately in older people with reduced physical and cognitive functions. OBJECTIVES: This study aimed to investigate the number of older adults who could not be tested for OD and to investigate their characteristics. METHODS: The participants included 145 older residents of an aged care nursing home. They were divided into two groups: those who could be tested for OD and those who could not, and their characteristics were compared. The degree of requiring long-term care was classified into five levels. The degree of dementia was classified into five levels. Those having difficulty in performing daily activities alone and having degree III or higher dementia were considered to have severe dementia. RESULTS: The participants included 41 men and 104 women with a median age of 89 years (range, 64-105 years). Sixty-eight participants failed the OD test (46.9%). In univariate and multivariate analyses, degree of dementia and oral care (among other characteristics in univariate analysis) showed statistically significant differences between the two groups. Cut-off values for older adults who could not perform OD test were level 4 or higher in need of care and degree III or higher in dementia. CONCLUSION: This study suggests that additional assessment tools for oral function should be considered for older adults requiring a nursing care level of 4 or higher and a dementia degree of III or higher.

Factors associated with the oral health status of patients with schizophrenia: A cross-sectional study.

BACKGROUND: Oral function deterioration attributed to ageing and medications is one of the main contributory factors of dysphagia. Therefore, oral health management is essential in older patients with schizophrenia. However, no previous studies have evaluated the oral function in patients with schizophrenia. OBJECTIVE: We surveyed patients with schizophrenia to identify factors associated with ageing-related variations in oral function. METHODS: This cross-sectional study included 34 male patients diagnosed with schizophrenia who were hospitalised at a psychiatric hospital between July and September 2021 and underwent a screening examination during dental care. The survey items included basic information, oral hygiene information, oral (oral diadochokinesis [ODK] and tongue pressure), physical function, and nutritional status. Thirty-six male community-dwelling older individuals were included as controls, and their outcomes were compared with those of patients with schizophrenia. RESULTS: Compared with healthy older adults, patients with schizophrenia demonstrated significantly lower teeth numbers, ODK, and calf circumference (CC) (p < .05). Multiple regression analysis revealed that ODK was associated with age and schizophrenia (p < .05). Conversely, tongue pressure was associated with CC (p < .05), suggesting different factors' association with the parameters indicating decreased oral function. CONCLUSIONS: Our study findings suggest that older patients with schizophrenia have decreased tongue pressure and generalised muscle mass, highlighting the need to manage oral function. Interventions for tongue pressure were more strongly associated with muscle mass and could be easier to manage than those with disease-dependent changes in ODK. TRIAL REGISTRATION: Retrospectively registered.

Signal to noise ratio of masticatory muscle activity of functional and non-functional oral tasks.

BACKGROUND: Electromyographic activity (EMG) of masticatory muscles during wakefulness is understudied. It is unclear if single channel ambulatory EMG devices are sensitive enough to detect masticatory muscle activity (MMA) during wakefulness. OBJECTIVES: To compare the MMA of various oral tasks recorded with a single channel EMG device ((Grindcare4-datalogger Prototype device) (GC4-ß)) and a conventional EMG (cEMG) device. METHODS: EMG activity of 30 standardised oral tasks was recorded unilaterally from the masseter and anterior temporalis muscle in 24 healthy volunteers using GC4-ß and a cEMG device. To compare the EMG data, signal-to-noise ratios (SNR) were calculated as a way to normalise EMG activity across tasks. Analysis of variance was used to compare the SNR between the devices, muscles and oral tasks. RESULTS: SNR measured from GC4-ß was overall significantly higher than the cEMG device (p =.001). The SNR for maximum voluntary contraction (MVC) was significantly higher than all other tasks (p <.001). SNR for temporalis with GC4-ß was significantly higher for MVC, hard food, soft food, gum chewing (dominant side), rhythmic clenching and upper lip biting compared to the cEMG device (p <.021). The SNR for masseter with GC4-ß was significantly higher for hard food and gum chewing (dominant side), rhythmic clenching, rhythmic biting of an object and yawning compared to the cEMG device (p <.022). CONCLUSIONS: This study provides novel insight into the EMG patterns of numerous oral tasks enhancing knowledge of physiological differences between the masticatory muscles. Further, single channel EMG devices can effectively measure the EMG activity of various oral tasks during wakefulness.

Relationships Between Test Results for Oral Hypofunction, Subjective Frailty Symptoms and Oral Health-Related Quality of Life of Japanese Dental Outpatients: A Multicentre, Cross-Sectional Study.

BACKGROUND: Oral hypofunction is the stage before oral dysfunction. The subjective symptoms of poor oral function and the decline in oral health-related quality of life (OHRQoL) that occur in the oral hypofunction stage can be missed. OBJECTIVE: This multicentre cross-sectional study was performed to examine the relationships between the test results for oral hypofunction, subjective frailty symptoms and OHRQoL of outpatients in dental clinics. METHODS: The basic characteristics and oral function test results of 637 dental clinic outpatients were evaluated. The subjective symptoms of physical and oral frailty were investigated using a questionnaire. OHRQoL was assessed using the Japanese short version of the Oral Health Impact Profile (OHIP-JP16) and OHRQoL dimension score. RESULTS: The overall prevalence of oral hypofunction was 37.8%, with no significant difference between men and women. No significant differences in the presence or absence of subjective symptoms of frailty and a high OHIP score were observed based on sex. However, the prevalence of oral hypofunction was significantly different among the age groups and increased with age. The subjective symptoms of frailty score, OHIP score and OHRQoL dimension score were significantly higher in patients with versus without oral hypofunction. Age, number of underlying diseases, total score for subjective symptoms of frailty, total score for OHIP and OHRQoL dimension score were significantly associated with oral hypofunction. CONCLUSION: Oral hypofunction may affect the subjective symptoms of frailty and OHRQoL in older adults.

Effectiveness of the lay health advisor program on oral function and quality of life in aboriginal older adults: A randomized controlled trial.

BACKGROUND: Aboriginal older adults residing in remote areas have poor oral function due to inadequate access to healthcare services. Lay health advisor (LHA) strategies can fill capacity shortages of healthcare professionals in rural communities and increase population acceptance of health care or healthy behaviours. OBJECTIVE(S): To evaluate the effectiveness the LHA program on oral function and oral health-related quality of life (OHRQoL) among older adults in aboriginal community. METHODS: Participants were randomly assigned to an experimental group (EG; n = 122) and a control group (CG; n = 118). All participants performed oral exercises, and the EG received additional one-on-one 30-min lessons by an LHA over 4 weeks. Data were collected through face-to-face interview and oral examination. The generalized estimating equation model was used to analyse changes in outcomes over time. RESULTS: The EG exhibited significantly greater improvement in swallowing (ß = .63) at the 6-month follow-up and in masticatory performance (ß = .52) and pronunciation of the syllable/pa/ (ß = 2.65) at the 2-week follow-up than the CG did. The EG had a significantly lower plaque control record (ß = -.14) and plaque index (ß = -.30) at the 3-month follow-up than the CG did. Moreover, the OHRQoL was significantly increased at 6-months follow-up in the EG (p = .010). CONCLUSION: The LHA program had positive effects on chewing, swallowing and plaque control in aboriginal older adults. LHA group also experienced positive long-term effect on OHRQoL after intervention.

Relationship between texture perception and oral function: A preliminary study in young, healthy adults.

BACKGROUND: Oral frailty, characterised by reduced oral function, is associated with systemic health issues in older adults. Although the criteria for diminished oral function often focus on motor and secretory abilities, texture perception also plays a crucial role in health due to its impact on food intake and palatability. OBJECTIVE: This study aimed to explore the relationship between thickness discrimination ability (TDA) and oral motor and secretory functions in healthy young individuals. METHODS: Twenty-eight adults were assessed for texture perception using eight concentrations of aqueous xanthan gum solutions to determine TDA scores. Measurements of occlusal force, masticatory performance, tongue pressure, stimulated salivary flow rate and tongue-lip motor function were conducted. Spearman's correlation analysis was used to evaluate the relationship between TDA scores and oral functions. Participants were divided into high-sensitivity and low-sensitivity groups based on their TDA scores to compare oral function test results. RESULTS: The TDA scores varied among the participants, with higher scores correlating with higher masticatory performance (r = 0.41, p < .05). Masticatory performance in the high-sensitivity group was significantly higher than in the low-sensitivity group (211.9 ± 59.2 mg/dL vs. 157.9 ± 43.0 mg/dL, p = .013), with no significant differences in other oral functions. CONCLUSION: Masticatory performance was correlated with TDA, suggesting a link between the selection function of mastication and thickness discrimination. These findings highlight the potential relevance of texture perception in oral function and indicate the need for further exploration, particularly in older adults with declining oral health.

Improvement of oral function and its impact on oral food intake in subacute stroke patients: A prospective study with dental intervention.

BACKGROUND: The association between oral food intake and oral function during the subacute stage of stroke is not well known. OBJECTIVE: To investigate (1) oral function changes in subacute stroke patients and (2) association between oral function and oral intake status at several time points. METHODS: In a prospective study involving 324 stroke patients at a convalescent rehabilitation unit, four oral function parameters (maximum tongue pressure, MTP; lip-tongue motor function, LTMF; maximum occlusal force, MOF and oral health assessment tool, OHAT) were quantitatively measured upon admission (T0), at 1 month (T1) and 2 months (T2). Oral feeding status was assessed using the Functional Oral Intake Scale (FOIS) and divided based on the FOIS score into the dysphagic and regular diet groups. The changes in oral functions at the three time points were tested using generalized estimating equation analysis. The association between FOIS groups and oral functions at T1 and T2 was analysed by means of logistic regression analysis. RESULTS: All oral function parameters improved significantly over time during the hospital stay (mean differences: 4.9 for MTP, 0.6 for LTMF, 1.1 for MOF and -1.8 for OHAT). The FOIS groups were significantly associated with MTP (p < .05) and OHAT (p < .05) at both T1 and T2. CONCLUSION: Our findings suggest that oral function significantly improves in patients during subacute stroke rehabilitation and better oral health can be associated with better oral intake. Improved oral function through dental intervention and oral rehabilitation may contribute to gains in oral food intake.

Time spent away from bed is associated with oral hygiene and oral function: A cross-sectional and multi-institutional study.

BACKGROUND: Spending time away from bed is important in older adults. Not doing so can lead to functional decline rapidly. OBJECTIVE: To investigate the association between oral function and time spent away from bed in older adults living in nursing homes. METHODS: We enrolled 748 adults aged ≥65 years across eight nursing homes between April 2022 and March 2023. 'Problems with oral hygiene' and 'problems with oral function' were the dependent variables in the multiple regression analyses to determine their association with time spent away from bed. RESULTS: We selected 304 participants (76 men; mean age, 86.3 ± 7.5 years) and divided them into three groups: group S (< 4 h), group M (4 to < 6 h) and group L (≥ 6 h), with 28, 23 and 253 participants, respectively. Comparison of the characteristics between the groups demonstrated significant differences in the Barthel index (p < .001), time spent away from bed (p < .001), history of aspiration pneumonia (p < .001), confirmation of meals and food forms (p = .010), problems with oral hygiene (p = .014), and problems with oral function (p = .002). Based on multiple regression analyses, 'problems with oral hygiene' (p < .001) and 'problems with oral function' (p < .001) were significantly associated with time spent away from bed. CONCLUSIONS: The time spent away from bed was significantly associated with both oral hygiene and function in older adults, suggesting the importance of extending the time that older adults spend away from bed.

Validation of the conceptual framework and intervention scope of oral function rehabilitation exercise.

OBJECTIVES: This study used a Delphi survey to define the concept of oral function rehabilitation exercise (OFRE) based on the International Classification of Functioning, Disability, and Health (ICF) and to categorise intervention domains for community-dwelling older adults. BACKGROUND: While numerous studies have been conducted to improve oral function through exercise interventions, the conceptual definition of oral exercise remains unclear and there is a lack of systematic categorisation of oral exercise intervention domains. METHODS: A preliminary model was developed based on the key findings of 19 papers selected from a prior systematic review. Its validity was confirmed through a Delphi survey conducted twice with eight expert panellists. Consensus was achieved by evaluating the validity of the OFRE conceptual framework, the accuracy of OFRE conceptual definitions, and intervention domains. RESULTS: Through expert consensus, an ICF-based OFRE conceptual framework was developed that includes 21 factors that affect the oral health status of the older adults. The OFRE intervention domain for improving the health status consisted of oral function rehabilitation warm-up exercise, masticatory function exercise, swallowing function exercise, articulatory function exercise, salivary function exercise, and oral function rehabilitation cool-down exercise, and 11 specific intervention methods were derived. CONCLUSIONS: The OFRE intervention can be used for planning and applying successful interventions to improve oral function and life function of older adults.

Exploring lived experiences on the usage of removable complete dentures among edentulous patients attending Makerere University Dental Hospital, Kampala, Uganda.

BACKGROUND: Edentulism remains a major disability worldwide, especially among the elderly population, although the prevalence of complete edentulism has declined over the last decades. In Uganda, the prevalence of edentulism in people aged 20 years and above is 1.8%. The therapy for edentulous patients can be realized through the use of conventional removable complete dentures, implant-supported prostheses, and computer-aided design and computer-aided manufacturing (CADCAM), however, the provision of removable complete dentures continues to be the predominant rehabilitation for edentulous patients. However, no published study has explored the lived experiences with removable complete dentures among the Ugandan population. The aim of the present study was to explore patients' lived experiences on the usage of removable complete dentures among Ugandan edentulous patients attending Makerere University Dental Hospital. METHODS: This was a qualitative study approach using purposive sampling. Fifteen (15) respondents were selected across social demographics. Interviews were recorded and transcribed and themes were generated to draw a deeper meaning to the usage of removable complete dentures. A qualitative statistical package, Atlas Ti software was used to generate themes from the interviews followed by an interpretation of the generated data and the results were presented as text and in a table. RESULTS: The reported key positive experiences due to removable complete denture rehabilitation were the improvement in speech, eating ability, regaining good facial appearance, better oral hygiene management, self-esteem and confidence to smile in public, and a feeling of completeness. However, respondents complained of pain and discomfort due to the looseness of dentures, inability to eat certain foods, and regular cleaning of dentures. The respondents did not go through proper informed consent processes before getting removable complete dentures. CONCLUSION: The study found that patients were satisfied with their removable complete dentures rehabilitation due to the positive experiences registered, such as the ability to eat and talk well, and restoration of self-esteem, all of which improved their quality of life. However, they experience pain and discomfort due to the looseness of dentures.

Physical, oral, and swallowing functions of three patients with type a xeroderma pigmentosum: a report of three cases.

BACKGROUND: Xeroderma pigmentosum (XP) is an extremely rare and severe form of photosensitivity. It is classified into types A-G or V according to the gene responsible for the disease. The progression and severity of symptoms vary depending on the type. Although dysphagia caused by decreased swallowing function and dental malposition due to stenosis of the dentition in the facial and oral regions is common, it has not been reported in detail. We report three cases of type A XP, in which central and peripheral neurological symptoms appeared early on and progressed rapidly. We describe the oral function of these patients, focusing on the swallowing function and dentition malposition. CASE PRESENTATION: Two males (27 and 25 years old) and one female (28 years old) presented with diverse neurological symptoms. We focused on the relationship between the changes in swallowing and oral functions and conditions due to decline in physical function. Some effects were observed by addressing the decline in swallowing and oral functions. In particular, a dental approach to manage the narrowing of the dentition, which was observed in all three patients, improved the swallowing and oral functions and maintained the current status of these functions. CONCLUSIONS: In type A XP, early decline in oral and swallowing functions is caused by the early decline in physical function, and it is necessary to monitor the condition at an early stage.

Activities of the dorsolateral and medial prefrontal cortices during oral function training with cognitive training elements: a NIRS study.

BACKGROUND: Cognitive function plays a crucial role in human life, and its maintenance and improvement are essential in both young and older adults. Since cognitive decline can be associated with oral function decline, preventing the decline in both cognitive and oral functions is an urgent social issue. Several training methods to improve each function have been proposed. Previous studies have indicated that greater brain activity during training is associated with increased benefits for cognitive function. Although adding cognitive function elements to oral function training may promote the activation of brain activity during oral function training, the effects have not been validated. The main purpose of this study is to develop a novel training program that combines oral function training with cognitive training, which is expected to activate key brain regions involved in oral and cognitive functions, such as the left dorsolateral prefrontal cortex (DLPFC) and right medial prefrontal cortex (mPFC). METHODS: Four types of training programs combining oral and cognitive training: PaTaKaRa × calculation, lip exercise × N-back, tongue exercise × inhibition, and tongue exercise × memory, were developed. Each program had seven levels of difficulty [level 0 (no cognitive load) and level 6 (maximum difficulty)]. Twelve healthy young adults participated in the study and were instructed to perform all four programs. Brain activity in the left DLPFC and right mPFC were measured during each training session using two-channel near-infrared spectroscopy (NIRS). RESULTS: No significant brain activity was observed during training at level 0. Brain activity in the left DLPFC was significantly increased at levels 1 and 2 and in the left DLPFC and right mPFC at level 6 during PaTaKaRa × calculation training. Brain activity in the left DLPFC was significantly increased at level 6 during tongue exercise × inhibition training. Brain activity in the left DLPFC and right mPFC was significantly increased at level 6 during lip exercise × N-back training. CONCLUSION: Oral function training did not significantly increase brain activity; nevertheless, oral function with cognitive training stimulated brain activity in the prefrontal cortex. TRIAL REGISTRATION: UMIN-CTR. ID: UMIN000039678. date: 06/03/2020.

[Association between depressive tendencies and oral diadochokinesis in the older adults in private residential nursing home].

AIM: This study aimed to investigate the relationship between depressive tendencies and oral diadochokinesis (ODK) in 24 older adults living in a private residential nursing home. ODK is an indicator of the oral function. METHODS: Depressive tendencies were assessed using the Geriatric Depression Scale 5, with scores of two or higher indicating probable depression. ODK was measured across four syllable tasks (/pa/, /ta/, /ka/, and /pataka/), which were evaluated using coefficient of variation (CV) values. Low CV values indicate superior performance. Potential confounders, including the cognitive function, sleep status, body mass index, instrumental activities of daily living, and physical function, were controlled. RESULTS: Five participants (20.8%) experienced depression. Individuals with depressive tendencies demonstrated significantly poor ODK performance (higher CV) in the /ta/ task and a marginally significant difference in the /ka/ task. No significant differences were observed between /pa/ and /pataka/. CONCLUSIONS: These findings suggest a link between depressive tendencies and reduced proficiency in specific ODK tasks among older nursing home residents. This finding implies that a decline in the oral function in articulating /ta/ and /ka/ syllables may precede other common depressive symptoms. Furthermore, depression monitoring could be a valuable tool for early detection of the oral function in this population, enabling timely interventions.

Oral function in completely edentulous patients rehabilitated with implant-supported dental prostheses: A systematic review and meta-analysis.

OBJECTIVES: This review evaluated the effects of rehabilitation with implant-supported prostheses on the oral function of completely edentulous adults. MATERIALS AND METHODS: Systematic literature searches were performed to identify records reporting on oral function in completely edentulous adults rehabilitated with implant-supported prostheses. Meta-analyses were performed on various outcomes including bite force, masticatory performance, muscle activity, mandibular movement/chewing pattern, and salivary flow. RESULTS: 5507 records were identified. Thirty studies qualified for data extraction and analysis. The kappa (𝛋) for the search and identification strategy ranged between 0.50 and 1.00. Meta-analysis was performed grouping the studies by outcomes and split by time points of 6-12 months, 12-36 months, and >36 months after implant therapy. The meta-analyses revealed a significant improvement in oral function of completely edentulous adults after rehabilitation with implant-supported prostheses at 6-12 months (Z = -4.895, p < .001; 95% CI: -0.703, -0.301; τ2 = .609; Q = 114.953, df = 17, p < .001; I2 = 85.2%), at 12-36 months (Z = -4.886, p < .001; 95% CI: -0.580, -0.248; τ2 = .908; Q = 280.611, df = 35, p < .001; I2 = 87.5%) and at more than 36 months (Z = -9.108, p < .001; 95% CI: -1.472, -0.951; τ2 = .019; Q = 7.918, df = 7, p = .340; I2 = 11.6%). The included studies demonstrated a low to moderate risk of bias. CONCLUSIONS: This systematic review concluded that the oral function of completely edentate adults significantly improved with implant-supported/retained prostheses, even when only one jaw received implant therapy. Therefore, implant therapy should be promoted for edentulous adults to alleviate the shortcomings of conventional complete removable dental prostheses.

Association between oral function and nutrition in gastric cancer patients undergoing chemotherapy.

OBJECTIVES: This study aimed to clarify the relationship between the oral assessment guide (OAG), a simple method for assessing oral function and poor nutrition in gastric cancer patients and investigate the reduction of oral mucositis through appropriate oral function management. SUBJECTS AND METHODS: Gastric cancer patients who underwent chemotherapy at the Nagoya Ekisaikai Hospital between January 2015 and December 2020 were evaluated. The prognostic nutritional index (PNI), as the objective variable, was used to assess nutritional status. The explanatory variables were sex, age, smoking status, body mass index (BMI), number of remaining teeth, cancer stage, albumin level, C-reactive protein level, white blood cell count and the OAG score. RESULTS: PNI was significantly associated with age, number of remaining teeth, cancer stage and the OAG score (p < 0.05) among the 217 patients. There were significant differences in age, BMI, cancer stage and the OAG score among the patients. An abnormal BMI and an advanced cancer stage were more common in older patients, and abnormal OAG scores were associated with a lower PNI. CONCLUSIONS: For gastric cancer patients undergoing postoperative chemotherapy, worse oral functional status is associated with worse PNI and nutritional status.