Search

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Evaluation of low tongue pressure is used to diagnose oral hypofunction. The pathophysiology of oral hypofunction is hypothesized to be associated with oral dysfunction related to ageing. Depression in older adults is a major problem and is related to handgrip strength, which is related to tongue pressure. We hypothesized that low tongue pressure could indicate depression mood in community‐dwelling older adults. Objectives: This study aimed to measure maximum tongue pressure and compare it to the responses to the Kihon Checklist (KCL), which is used to check mental and physical deterioration of community‐dwelling older adults. Methods: A total of 49 community‐dwelling independent older adults with stable dental condition (23 men, 26 women; median age, 79 years) answered the KCL, which contained questions on frailty status, cognitive function, nutritional and sarcopenia status. Oral function was measured to assess oral hypofunction. The relationship between tongue pressure differences and frailty status, cognitive function, nutritional and sarcopenia status was analysed using logistic regression analyses after adjusting for age and sex. Results: Nine participants (6 men and 3 women; median age, 81 years) had a tongue pressure <23.0 kPa, which was the lowest limit of the standard value of maximum tongue pressure in patients aged ≥70 years. Logistic regression analyses showed that only Question 21, which is related to a lack of fulfilment in daily life, was significantly associated with low tongue pressure (p =.027). Conclusion: Low tongue pressure may be associated with sociopsychological factors in older adults. [ABSTRACT FROM AUTHOR]

Background: A rise in tongue pressure coincides with an increase in the suprahyoid muscle activity. Objectives: The aim was to investigate the effects of holding a weighted plastic bottle on tongue pressure and the suprahyoid muscle activity. Methods: Eighteen participants (8 men and 10 women; mean age 42 ± 16 years) participated in this study. All participants had no history of speech, language, hearing or swallowing disorders and no tooth loss, and they did not require dentures. Healthy participants held gauzes connected with a plastic bottle with increasing resistive loads of 0 g, 250 g, 500 g and 750 g, between their palate and tongue. The maximum tongue pressure and average tongue pressure were measured during a 5 s hold. The average tongue pressure was defined as the mean tongue pressure data in each task. The suprahyoid muscle activity was measured using the electromyogram (EMG). The root mean square of the EMG signals measured while lifting different loads and while performing the head lifting exercises was compared. All variables were examined using the Friedman's test and Wilcoxon signed‐rank test. Results: The maximum tongue pressure (p <.05) and average tongue pressure values (p <.05) increased gradually in the anterior‐median region with increasing resistive loads, and the root mean square amplitudes for 250 g, 500 g and 750 g were not significant compared with head lifting exercises. Conclusion: These results indicated that plastic bottle holding could be a potential strength training tool for the tongue and the suprahyoid muscles. [ABSTRACT FROM AUTHOR]

Background: There have been no standard protocols of oral exercises for maintaining and improving oral function for people with dementia. Objective: This study aimed to determine the effects of home‐based oral exercises on the oral function of people with mild to moderate dementia. Methods: Twenty‐two participants at King Chulalongkorn Memorial Hospital were randomly assigned to the exercise group (n = 11) or control group (n = 11). The exercise group was instructed to do three home‐based oral exercises, consisting of tongue‐strengthening, oral diadochokinesis (ODK) and mouth‐opening exercises, for 3 months, while the control group received advice on oral health care. The maximum tongue pressure (MTP) was the primary outcome. MTP, ODK rates of /pa/, /ta/, /ka/, modified water swallowing test (MWST) and oral moisture were measured at baseline, and after 1, 2 and 3 months of training. The generalised estimating equation analysis was used to evaluate the effects of oral exercises on the oral function. Results: The MTP and all ODK rates in the exercise group were significantly increased after 3 months of training. There were significant interaction effects between time and intervention in MTP and all ODK rates. No significant interaction effects between time and intervention in oral moisture were found. The MWST scores in both groups did not change through the end of study, and no adverse effects were reported. Conclusion: Home‐based oral exercises were found to be effective for improving tongue strength and tongue‐lip motor function in people with mild to moderate dementia. [ABSTRACT FROM AUTHOR]

Oral dysfunction, including oral uncleanness and decline in tongue motor function, tongue pressure and swallowing function, precedes frailty. The tongue's dorsum is a reservoir of oral microbiota, desquamated epithelial mucosa and leukocytes due to the multi‐papillate anatomy, and leads to tongue coating. The tongue coating is frequently found in older adults because of hyposalivation, immunity's hypoactivity, diminished motor function and compromised tongue's pressure with age. Anaerobe‐driven volatile sulphur compounds in tongue coating are a major cause of intra‐oral malodor. Dysbiosis of the tongue‐coating microbiome rather than the amount of microorganisms is associated with a risk of aspiration pneumonia. Daily tongue cleaning with a brush or scraper is an easy way to control tongue coating deposits and quality. Using mouth wash or rinse‐containing germicides is also a way to control the microbiota of tongue coating. The tongue function is closely related to swallowing. Tongue and suprahyoid muscles are linked with respiratory muscles through the endothoracic fascia. The mechanical stimulation during the cleaning of the tongue may stimulate the respiratory muscles. An intervention trial revealed that tongue cleaning by mucosal brush improves tongue pressure, swallowing and respiratory function in old residents of nursing homes, suggesting a rehabilitative effect of tongue cleaning on the swallowing and respiratory functions, preventing aspiration pneumonia. This narrative review assesses the tongue‐cleaning benefits for respiratory and swallowing functions and the possibility of preventing aspiration pneumonia. [ABSTRACT FROM AUTHOR]

Background: Rate force development is associated with performance and muscle composition in whole‐body muscle. Although rate force development on tongue muscle can be examined using tongue pressure waveform, there have been only few investigations on this topic. Objectives: This study's main purpose was to investigate the reliability of tongue pressure waveform analysis and its relationship with articulation and tongue muscle composition. In addition, we also investigated the association between tongue muscle composition and articulation. Methods: Forty‐five community‐dwelling individuals aged >20 years participated. We analysed tongue pressure waveform, including maximum tongue pressure (MTP), time to peak, mean rate of tongue force development and peak rate of tongue force development (PRTFD). We also assessed oral diadochokinesis. Magnetic resonance imaging of the tongue provided data on tongue muscle composition, including tongue volume, fat mass, lean muscle mass and fat percentage. We evaluated the reliability of tongue pressure waveform analysis. Moreover, we examined the coefficients between tongue pressure waveform analysis, oral diadochokinesis and tongue composition. Results: We detected a high reliability of MTP and PRTFD. MTP and PRTFD were significantly correlated with tongue muscle composition. MTP was not significantly correlated with oral diadochokinesis. PRTFD was significantly positively correlated with oral diadochokinesis. Tongue fat mass and fat percentage were negatively correlated with oral diadochokinesis of /ta/ and /ka/. Conclusions: Peak rate of tongue force development is a highly reliable method for tongue pressure analysis and is useful for elucidating the functional importance of tongue muscle function on articulation. We speculated that fatty infiltration of the tongue adversely affects articulation. [ABSTRACT FROM AUTHOR]

Introduction: Reduced tongue pressure may render eating and swallowing difficult. The purpose of this study was to investigate whether the tongue training device can also be used as a diagnostic device and whether its sensitivity and specificity are equal to the numerical tongue pressure measuring device. Material and Methods: The target group is patients aged 70 years and over who are hospitalised for rehabilitation. Tongue pressure was measured by both, a tongue pressure measuring instrument and a tongue training tool. The diagnosis of the reduced tongue pressure was made with the tongue pressure measuring instrument and set the verified with the novel tongue training tool. Results: Sixty‐two participants were included in the study. Forty‐five were classified by the tongue pressure measuring device and 53 by the tongue training device as 'low tongue pressure'. Spearman correlation confirmed a positive correlation between the tongue pressure measuring device and the tongue training device rs = 0.800, p = 0.01 level (2‐tailed). The tongue training device test identified sensitivity was 100%, and its specificity was 52.9%. The AUC of the ROC curve is 0.901. Conclusion: The tongue training device seems a simple, safe and readily available alternative to the tongue pressure measuring device for the diagnosis of low tongue pressure, with an excellent sensitivity and very good specificity. [ABSTRACT FROM AUTHOR]

Background: The tongue functions by modulating according to bolus volume when swallowing; however, associated tongue dynamics are unclear. Objective: We aimed to clarify how tongue motion and tongue pressure change with bolus volume during swallowing. Methods: Sixteen healthy volunteers (age 29.5 ± 3.8 years; 12 males, 4 females) were recruited. Two electromagnetic articulography markers were attached, one each on the anterior and posterior parts of the tongue, to measure motion. A sensor sheet, with five pressure‐sensitive points, was attached to the hard palate to measure tongue pressure. Participants were asked to swallow 3 ml and 10 ml of water. Motion trajectory, maximum velocity, vertical displacement just before contact with the hard palate, and maximum magnitude and duration of tongue pressure were analysed. Results: Tongue rotation was observed in the sagittal plane; its rate of appearance was significantly higher when swallowing 3 ml of water than when swallowing 10 ml, and the rate of rotation at posterior part was significantly higher than at the anterior part. The maximum velocity and vertical displacement were significantly greater when swallowing 10 ml of water than those when swallowing 3 ml of water. There was no significant difference in either the maximum magnitude of tongue pressure or maximum duration of tongue pressure between 3 ml and 10 ml. Conclusion: Bolus volume influenced the pattern of tongue motion; however, there was no difference in tongue pressure. [ABSTRACT FROM AUTHOR]

Objective: The aim of this 1‐year longitudinal randomised controlled trial was to evaluate the effectiveness of tongue cleaning on the maintenance of respiratory function in older adults requiring care. Methods: The participants included 24 residents of two nursing homes in Kitakyushu, Japan. The participants were randomised to receive tongue cleaning with routine oral care (intervention group, n = 12), or routine oral care alone (control group, n = 12). Among the participants, three in the intervention group and four in the control group had cerebrovascular disease history, four in the intervention group and four in the control group had a history of cardiac disease, and five in the intervention group and four in the control group were without medical history. Respiratory function was assessed on the basis of the peak expiratory flow rate (PEFR). Tongue pressure, swallowing function, oral health status, activities of daily living and nutritional status were also measured at baseline and at the end of the 1‐year follow‐up period. Results: The number of analysed participants in each group was 12. In the control group, the PEFR (1.6 [0.4‐4.2] L s−1 vs 1.4 [0.4‐3.2] L s−1, P =.034) and tongue pressure (16.4 [1.7‐35.2] kPa vs 8.0 [1.4‐38.6] kPa, P =.032) significantly declined after 1‐year. However, the PEFR (1.5 [0.8‐2.9] L s−1 vs 1.6 [0.7‐4.2] L s−1, P =.366) and tongue pressure (18.1 [4.2‐37.1] kPa vs 16.1 [5.2‐41] kPa, P =.307) were maintained in the intervention group. The change in the PEFR was significantly greater in the intervention group compared with the control group (0.130 [−0.45‐1.70] L s−1 vs −1.70 [−10.00‐10.00] L s−1, P =.028). Conclusion: Our findings suggest that tongue cleaning may help maintain tongue and respiratory function in older adults requiring care. [ABSTRACT FROM AUTHOR]

Objectives: Tongue pressure (TP) is used for the diagnosis of oral hypofunction; however, the impact of several variables on TP is unclear. Therefore, the current systematic review and meta‐analysis aimed to analyse the variability in tongue pressure among healthy individuals aged ≥60 years vs <60 years. Secondary outcomes were the influence of gender and the type of measuring device (Iowa Oral Performance Instrument (IOPI) vs JMS tongue pressure measurement device (JMS)). Methods: PubMed and the Japanese database Ichushi‐Web were searched systematically by two independent reviewers for studies reporting TP values in healthy populations. Clinical studies published between 1959 and June 2020 with more than 10 participants, written in English, German or Japanese, were included. A random‐effects meta‐regression for aggregate‐level data was applied (α < 0.05). Results: Sixty‐eight studies reported TP for a total of 13 773 subjects aged <60 years (n = 3265) and ≥60 years (n = 10 508). TP was significantly higher in subjects <60 years (estimated weighted mean (EWM) ± standard error = 51.9 ± 1.28 kPa; 95% CI = 49.4‐54.4) relative to those ≥60 (EWM = 34.7 ± 0.94 kPa; 95% CI = 32.8‐36.5) (P <.001), men (EWM = 45.9 ± 2.09 kPa; 95% CI = 41.8‐50.0) relative to women (EWM = 39.3 ± 1.68 kPa; 95% CI = 36.0‐42.6) (P =.015) and when assessed with the IOPI (EWM = 51.9 ± 1.32 kPa; 95% CI = 49.3‐54.5) compared to the JMS (EWM = 33.5 ± 0.63 kPa; 95% CI = 32.2‐34.7) (P <.001). In terms of gender, there was no significant difference in TP among subjects ≥60 years (P =.282). However, in subjects younger than 60, a significant difference was observed (P =.004). Conclusions: Healthy populations aged <60 years showed significantly higher TP than those aged ≥60 years. TP values ascertained by the IOPI are significantly higher than those obtained with the JMS. [ABSTRACT FROM AUTHOR]

Background: Oral myofunctional therapy (MFT) is an effective treatment for mild‐to‐moderate obstructive sleep apnoea (OSA) in middle‐aged patients. However, few reports have described its use in elderly patients with moderate and severe OSA. Moreover, no studies have examined the relationship between changes in tongue pressure with MFT and the severity of OSA. Objective: We conducted an interventional study using MFT to evaluate the effect of MFT on middle‐to‐senior‐aged patients with moderate or severe OSA and compared changes in apnoea‐hypopnea index (AHI) and tongue pressure. Methods: Thirty‐two OSA patients (≥45 years) treated with continuous positive airway pressure (CPAP) were included. MFT was performed in parallel with CPAP. Three days after CPAP discontinuation, polysomnographies were performed and tongue pressures were measured before and after MFT. Results: Patients were 69.3 ± 1.5 years old. After 6 months of MFT, AHI decreased significantly from 34.7 to 29.0/h (P =.03), while tongue pressure significantly increased from 35.9 to 45.6 kPa (P <.01). Seven patients (22%), including 6 of the 12 patients with moderate OSA (50%), experienced successful CPAP discontinuation. Conclusions: MFT can be a useful intervention even among middle‐aged to elderly patients with OSA. Increased tongue pressure may have contributed to the AHI improvement. Clinical trials: Trial registration at www.umin.ac.jp UMIN000027547. [ABSTRACT FROM AUTHOR]

Background: Tongue muscle strength is important for swallowing but decreases with age, in association with reduced skeletal muscle mass. However, the relationships between pharyngeal dynamics and both skeletal muscle mass and tongue muscle strength are unknown. Objective: To investigate the effect of reductions in tongue muscle strength on pharyngeal movement during swallowing in patients with dysphagia. Methods: Subjects were selected from male outpatients ≥65 years old who were examined for the main complaint of dysphagia. Patients with history of neurodegenerative disease affecting tongue movement, cerebrovascular disease or oral cancer were excluded. As a result, 82 men (mean age, 80.6 ± 6.8 years) participated. Skeletal muscle mass index (SMI) as physical parameters and maximum tongue pressure (MTP) as tongue muscles strength were measured. Status and dynamics of the pharyngeal organs, including change in posterior pharyngeal wall advancement (PPWA) when swallowing 3.0 mL of moderately thick liquid, were measured by analysing videofluoroscopic images. Simple bivariate correlation and multiple regression analysis were used to statistically analyse correlations between parameters. Results: MTP showed a significant positive correlation with SMI (r =.43, P <.01). PPWA showed a significant negative correlation with MTP (r = −0.30, P <.01), but no association with SMI. Conclusions: While tongue muscle strength is affected by skeletal muscle mass, posterior pharyngeal wall advancement is not readily affected by decreases in skeletal muscle mass. Posterior pharyngeal wall advancement may increase to compensate for swallowing function among individuals with reduced tongue muscle strength. [ABSTRACT FROM AUTHOR]

Background: Tongue motor biomechanics during swallowing was not fully elucidated due to the technical difficulty. Objective: To evaluate the relationship between tongue motion and tongue pressure production by simultaneously measuring tongue motion and tongue pressure during water swallowing. Methods: In 12 healthy male participants (mean age, 30.8 ± 4.2 years), tongue pressure and tongue motion trajectory during dipper‐ and tipper‐type swallows of 3 mL of water were measured using a sensor sheet system equipped with five sensing points and an electromagnetic articulography, respectively. The temporal correlation between motion of anterior/posterior tongue and tongue pressure production during swallowing was evaluated on the synchronised waveforms. Results: In the dipper‐type swallow, a similar up‐and‐down motion pattern in vertical direction was observed among all participants before tongue pressure production. Those motion patterns were common at the anterior and posterior tongue locations with a temporal difference in some segment of tongue motion. On the other hand, tongue directly attached to hard palate with temporal synchronicity between the anterior and posterior parts. In both types of swallow, a strong temporal correlation was found between the timing of tongue‐palate contact and the Onset of tongue pressure by intra‐class correlation coefficients. Conclusion: From the simultaneous measurement of tongue motion and tongue pressure production, the tongue motion pattern during water swallowing and the temporal correlation between tongue motion and tongue pressure production were elucidated. [ABSTRACT FROM AUTHOR]

Background: There is growing international interest in the prevention of decreased oral function for managing oral health in older people. Objective: The aims of the present study were to identify factors related to decreases in masticatory performance and masticatory function until swallowing in subjects aged 20‐79 years old. Methods: A total of 152 subjects, ranging in age from 20 to 79 years, were divided into six groups according to their chronological age: 20‐29, 30‐39, 40‐49, 50‐59, 60‐69 and 70‐79 years. Grip strength, maximum occlusal force, maximum tongue pressure, masticatory performance and swallowing threshold were measured in all subjects. Masticatory performance and swallowing threshold were determined according to the concentration of dissolved glucose obtained from gummy jellies; decreased masticatory performance and decreased swallowing threshold were defined as glucose concentrations in the lowest 20th percentile. A multivariate binary logistic regression analysis was used to identify factors associated with decreased masticatory performance and decreased swallowing threshold. A self‐administered lifestyle questionnaire was also completed. Results: Logistic regression analyses revealed that factors related to decreased masticatory performance included use of more than one kind of medicine for treating chronic diseases and removable denture use, while factors related to decreased swallowing threshold included eating between meals once or more per day, poorer mental health and decreased saliva flow. Conclusions: Different factors are related to decreased masticatory performance and decreased swallowing threshold, although both of these phenomena are closely associated with general health status. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia in the oral region, including the tongue, leads to declined swallowing function and dysphagia. Muscle mass and strength, and motor function in the oral region have not been examined together, and the relationship between generalised and oral sarcopenia remains unclear. Objective(s): The purpose of this study is to clarify the relationship between generalised sarcopenia and oral sarcopenia in the elderly in order to facilitate the establishment of a method for assessing oral sarcopenia. Methods: A total of 54 elderly persons participated in this study. We examined the skeletal muscle mass index (SMI), grip strength (GS) and walking speed (WS) as the index of generalised sarcopenia, and the cross‐sectional area of the geniohyoid muscle (CSG), tongue pressure (TP) and oral diadochokinesis (ODK) as the index of oral sarcopenia. Results: We found a moderate correlation between CSG and SMI, a weak correlation between GS and TP, and a moderate correlation between WS and ODK. CSG, TP and ODK were significantly smaller in the sarcopenia group than in the non‐sarcopenia group. By multiple regression analysis, SMI and TP were significantly associated with CSG. ODK, BMI and CSG were significantly associated with TP. WS and SMI were significantly associated with ODK. Conclusion: CSG, TP and ODK were confirmed as endpoints of oral sarcopenia. All endpoints of oral sarcopenia were influenced by those of generalised sarcopenia. [ABSTRACT FROM AUTHOR]

Background: Tongue lift movement (TLM) task is considered a treatment strategy in dysphagic patients. However, there is no evidence of effect of sustained tongue movements on the related muscle contraction. Objectives: The present study aimed to characterise the properties and time‐dependent changes of the electromyographic (EMG) features of suprahyoid muscles during TLM. Methods: Twenty young healthy volunteers were instructed to perform TLM at maximum effort in either the anterior or the posterior position, during measurement of tongue pressure for 7 s. Supra‐ (S‐hyo) and infra‐hyoid (I‐hyo) EMGs were recorded. The area and power frequency of EMG burst and the area under the curve of tongue pressure were compared among the conditions: trials (1st, 2nd vs 3rd trials); anterior vs posterior TLM; and early vs late 3 s of each trial. Results: There was no difference in the tongue pressure among trials or between the early and late 3 s. Anterior tongue pressure was significantly higher than posterior tongue pressure (P <.001). The area of I‐hyo EMG burst was significantly larger (P =.044), and the power frequency of I‐hyo EMG burst was significantly smaller (P =.042) during posterior TLM than anterior TLM. A significant difference in the power frequency of both EMG bursts was observed between early and late stages during both anterior (P <.05) and posterior (P <.01) TLM. Conclusion: Hyoid muscles may compensate for rapid fatigue of the tongue muscle to maintain tongue pressure by changing their activity pattern during tongue pressure generation. [ABSTRACT FROM AUTHOR]

Summary: Background: Tongue plays an important part in oral and maxillofacial system. Measurement of tongue pressure helps to evaluate the performance of tongue movement. Objectives: To establish a system for measuring tongue pressure against hard palate and to preliminarily explore pressure distribution of individual normal occlusions and the relationship with dental arch form. Methods: A total of 19 volunteers of individual normal occlusions out of 189 dental students met inclusion criteria (nine males, ten females, aged 25.53 ± 0.96 years). A force‐sensing resistor device was used to measure tongue pressure at rest and functional state (swallowing). We observed tongue pressure of four channel (anterior, posterior and lateral sides of hard palate) in sitting, supine position and swallowing. We analysed pressure differences according to gender and explored correlation relationship between tongue pressure and dental arch width and length using 3D digital maxillary image. Results: In rest, tongue pressure against hard palate increased from front to back in both sitting and supine position, without gender differences. When swallowing saliva, the pressure at lateral sides of females was found significantly higher than that of males. Bivariate correlation analysis revealed duration of swallowing was positively correlated with BMI and weight at posterior region and positively correlated with palatal length at anterior palate. The greater the dental arch width, the smaller the pressure of swallowing in the anterior and lateral region. Conclusion: In rest, there was consistent pressure of tongue against hard palate. The pressure increased significantly during swallowing, especially in females. Tongue pressure was related to dental arch length, width, BMI and weight. [ABSTRACT FROM AUTHOR]

Summary: 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 (β = −0.153), BMI (β = 0.205), HGS (β = 0.298) and MOF (β = 0.239) in the adult group (all P < 0.001) and with age (β = −0.266, P < 0.001), BMI (β = 0.160, P = 0.005), MOF (β = 0.217, P = 0.001) and tooth loss (β = 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. [ABSTRACT FROM AUTHOR]

Summary: During childhood, perioral muscle function is closely associated with malocclusion. To clarify the effects of tongue function on maxillofacial morphology in children, tongue pressure and maximum lip‐closing force (LCF) were measured and the relationship between perioral muscle function and maxillofacial morphology was evaluated according to the skeletal classification. Maximum tongue pressure (MTP) and swallowing tongue pressure (STP) were measured on the anterior palatine rugae in 100 children (Hellman's dental stages IIIA‐IIIC) using a balloon‐type tongue pressure measurement device. Lip‐closing force was measured using an LCF measurement device. Lateral cephalograms were examined to classify subjects into skeletal (S)‐I, S‐II and S‐III groups. Correlations of skeletal classification with tongue pressure and LCF were examined. Correlations of lateral cephalometric measurements with palatal volume (PV), measured using a three‐dimensional optical scanner, were evaluated. Maximum tongue pressure was significantly lower in the S‐II group than in other groups. Swallowing tongue pressure was significantly lower in the S‐II group than in the S‐III group. Lip‐closing force was significantly higher in the S‐III group than in other groups. Swallowing tongue pressure was positively correlated with MTP and PV. Correlations between tongue pressure and anteroposterior skeletal classification indicated the importance of quantitative tongue function assessment. [ABSTRACT FROM AUTHOR]

Elevation of the posterior part of the tongue is important for normal deglutition and speech. The purpose of this study was to develop a new surface electromyography (EMG) method to non-invasively and objectively evaluate activity in the muscles that control lifting movement in the posterior tongue. Neck surface EMG (N-EMG) was recorded using differential surface electrodes placed on the neck, 1 cm posterior to the posterior border of the mylohyoid muscle on a line orthogonal to the lower border of the mandible. Experiment 1: Three healthy volunteers (three men, mean age 37·7 years) participated in an evaluation of detection method of the posterior tongue lifting up movement. EMG recordings from the masseter, temporalis and submental muscles and N-EMG revealed that i) N-EMG was not affected by masseter muscle EMG and ii) N-EMG activity was not observed during simple jaw opening and tongue protrusion, revealing the functional difference between submental surface EMG and N-EMG. Experiment 2: Seven healthy volunteers (six men and one woman, mean age 27·9 years) participated in a quantitative evaluation of muscle activity. Tongue-lifting tasks were perfor-med, exerting a prescribed force of 20, 50, 100 and 150 gf with visual feedback. For all subjects, a significant linear relationship was observed bet-ween the tongue-lifting force and N-EMG activity ( P < 0·01). These findings indicate that N-EMG can be used to quantify the force of posterior tongue lifting and could be useful to evaluate the effect of tongue rehabilitation in future studies. [ABSTRACT FROM AUTHOR]

Motor functions of masticatory organs such as the tongue, lips, cheeks and mandible are known to deteriorate with age, thereby influencing masticatory performance. However, there are few reports on the relationships between tongue and lip functions and masticatory performance. To investigate the relationship between tongue and lip functions and comprehensive masticatory performance, by evaluating crushing, mixing and shearing abilities in young dentate adults. Participants comprised 51 dentate adults with a mean age of 25 years. Maximum tongue pressure and oral diadochokinesis were measured to evaluate tongue and lip functions. A multiple sieving method using peanuts was performed to evaluate crushing ability. A colour-changeable chewing gum was performed to evaluate mixing ability. A test gummy jelly was performed to evaluate shearing ability. The relationship between tongue and lip functions and each masticatory performance was assessed using Pearson's correlation coefficients. In addition, stepwise multiple regression analysis was performed to identify predictors of crushing ability. Crushing ability was significantly correlated with maximum tongue pressure and the number of repetitions of the syllables /pa/, /ta/ and /ka/. Maximum tongue pressure and number of repetitions of the syllable /pa/ were identified as significant predictors for crushing ability. Mixing ability was significantly correlated with the number of repetitions of the syllable /pa/. Shearing ability was not significantly correlated with tongue and lip functions. Masticatory performance during the chewing of brittle foods such as peanuts and solid foods such as chewing gum appears to be correlated with tongue and lip functions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of the tongue rotation exercise training on the oral functions using the measurement of maximum tongue pressure ( MTP) and labial closure strength ( LCS) in normal adults. In experiment 1, the differences in MTP and LCS at the measurement point for both groups with and without tongue rotation exercise training were examined. We instructed subjects to perform the tongue rotation exercise for 2 months. We measured MTP and LCS at the point before training and at the points of 1 and 2 months after the beginning of training. In experiment 2, the changes of MTP and LCS based on the sex differences and the measurement points in training were examined. We instructed subjects to perform the tongue rotation exercise for 3 months, and measured MTP and LCS at the point before training and at the points of 2 weeks and 1, 2 and 3 months after the beginning of training. The results of experiment 1 showed MTP and LCS increased with the progress of continuous training. The results of experiment 2 showed MTP and LCS were always higher in men than in women and increased significantly at 2 weeks of training in both sexes ( P < 0.01). These results might be suggested that the tongue rotation exercise training was effective for the recovery of the activity of the stomatognathic system. [ABSTRACT FROM AUTHOR]

We investigated the impact of tongue-thrusting on lingual pressure during fluid intake with a straw. In this study, 12 healthy young dentate individuals (two women and 10 men; 19-33 years) were instructed to drink 15 mL of water with a regular drinking straw at 37 °C, when indicated by the investigator. Participants drank after adjusting tongue position to one of the following patterns: (i) Holding the tip of the straw between the lips (Normal Position: NP), (ii) Sticking out the tongue to the vermilion zone of the lower lip and inserting the straw 1 cm past the front teeth (Tongue-thrusting Position: TP). Five recordings were conducted for each participant in a randomised order. To measure tongue pressure during swallowing, a specially designed 0·1-mm thick sensor sheet (Nitta, Osaka, Japan) with a tactile system for measurement of pressure distribution (I-SCAN; Nitta) was used. Duration, maximal magnitude and integrated value of tongue pressure were analysed based on the wave of tongue pressure recorded while water was swallowed. Magnitude, duration and integrated value of tongue pressure were significantly lower in TP than in NP at the median line (Ch1-3). Magnitude and integrated value of tongue pressure at the lateral part of the tongue (Ch5) were significantly lower in TP than in NP. When duration, maximal magnitude and integrated values were compared by channel, no significant differences were observed in NP, but a significant difference was found between Ch3 and the lateral areas Ch4/Ch 5 in TP. When the tongue was thrust forward, movement dynamics of the entire tongue changed and influenced contact between the tongue and palate during liquid intake with a straw. The impact was noticeably weaker on the median line than in lateral areas. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the association between strength of the perioral muscles and masticatory performance. Subjects were 56 healthy adults (30 men and 26 women; mean age of 24·9 years) with normal occlusion. Perioral muscle pressure was measured using JMS tongue pressure measurement device, and maximum tongue pressure and cheek pressure on the habitual chewing side (H) and non-habitual side (non-H) were measured. The masticatory performance was evaluated using gummy jelly, and the amount of glucose extracted was measured after chewing under condition H or non-H. The association between sex and maximum tongue pressure was analysed using Student's t-test. Cheek pressure and the amount of the glucose extracted between condition H and non-H or between men and women were analysed by two-way repeated-measures anova. In addition, the correlations between maximum tongue pressure and cheek pressure on condition H, maximum tongue pressure and the amount of glucose extracted under condition H, and cheek pressure and the amount of glucose extracted under condition H were analysed using Pearson's correlation coefficients for men and women. The maximum tongue pressure, cheek pressure and the amount of glucose extracted were higher in men than in women. The amount of glucose extracted was higher under condition H than under condition non-H, but no significant difference in chewing side was observed in cheek pressure between men and women. Additionally, positive correlations were shown between maximum tongue pressure, habitual-side cheek pressure and the amount of glucose extracted on men and women. In conclusion, the association between higher perioral muscle pressure and better masticatory performance was shown. [ABSTRACT FROM AUTHOR]

The tongue assumes an important role in bolus formation and transportation to the oropharynx and in retaining pharyngeal pressure during mastication and swallowing. Although the state of tongue-palate contact during swallowing is thought to change with bolus type, the details of these changes have yet to be clarified under normal physiological conditions. The purpose of this study was to examine the effect of bolus type on tongue pressure production against the hard palate during swallowing. Tongue pressures during swallowing 10 mL of water and 10 g of pudding and during dry swallow were measured with a sensor sheet system with five measurement points to evaluate normal physiological swallowing in 10 healthy dentate individuals. There was a common pattern in the sequential order of tongue pressure generation among the three swallowing conditions: tongue pressure was generated significantly earlier at the anterior-median part, followed by the posterior parts. During swallowing pudding and dry swallow, the duration of tongue pressure tended to increase at all channels except for the posterior-median part. The maximal magnitude of tongue pressure was significantly higher when swallowing pudding than when swallowing water at all channels except for the posterior-median part. The integrated value of tongue pressure was significantly higher when swallowing pudding than when swallowing water at all channels except for the posterior-median part. From these results, it was considered the tongue changed the sequential order, the duration and the magnitude of tongue pressure production according to the swallowing conditions (liquid swallowing, semisolid swallowing, dry swallow). [ABSTRACT FROM AUTHOR]

Summary Tongue pressure measured with a disposable hand-held balloon probe has been used for assessing tongue function; however, no diagnostic standard for assessing other oral functions exists currently. In this study, to develop a method for multifactorial manometric evaluation of oral functions, 20 men and 20 women (21-32 years of age) were instructed to apply 7-s maximal voluntary muscular effort on a hand-held balloon probe placed against the anterior and lateral parts of the palate, buccal surface of the molars on the habitual chewing side and labial surface of the anterior teeth for measuring anterior and posterior tongue, cheek and lip pressures (LPs), respectively. Intra-session reproducibility was determined by three repeated measurements, and associations between the obtained and the conventional data on oral diadochokinesis were tested. The men exhibited higher values of all the pressure types. Further, both genders showed a positive correlation between anterior and posterior tongue pressures (PTPs) ( P < 0·05), but only the women exhibited positive correlations between anterior tongue and cheek pressures, cheek and PTPs, anterior tongue and LPs, and cheek and LPs ( P < 0·05). No statistically significant correlation was found between the pressures and the number of syllabic articulations, except between LP and the number of /pa/ articulations in the women ( r = 0·524, P < 0·05). In conclusion, the balloon probe method enables objective manometric evaluation of oral functions and could be an effective tool for clinical epidemiological studies and evidence-based decision-making in nursing care. [ABSTRACT FROM AUTHOR]

The purpose of this study was to clarify which physiological and anatomical factors were involved in the formation of tongue indentations, which are believed to be a clinical sign of clenching. Twenty-four dentulous subjects were investigated. They were divided into two groups, depending on the presence or absence of tongue indentations: (i) a tongue indentation group and (ii) a no tongue indentation group. Intraoral appliances containing a small pressure sensor were placed at the lingual surfaces of the upper and lower right first molars. Lingual pressure on the lingual surfaces of the upper and lower right first molars was then recorded under different conditions. The tasks selected as physiological factors to be recorded were: (i) silent reading at rest for 10 min, (ii) maximum voluntary clenching (MVC) for 5 s, (iii) 10% of MVC for 1 min and (iv) swallowing. The results for all tasks were compared between groups. Tongue width and dental arch width were also measured as anatomical factors. No significant differences were found between groups during silent reading at rest, clenching, swallowing, or in tongue pressure integration during silent reading at rest. However, a significant difference was found in terms of tongue width ( P < 0·05). These results indicate that neither volume of lingual pressure exerted on the lingual surface of the teeth during rest, clenching, nor swallowing are related to the formation of tongue indentations. The results do suggest; however, that tongue width at rest plays an important role in the formation of tongue indentations. [ABSTRACT FROM AUTHOR]

The aim of this study was first to investigate whether the covering of the palatal mucosa with a denture base affects or not the bolus-propulsion time, and second if there was such an effect then investigate the possible contributory factors which have influence on the propulsion time. The propulsion time was measured in 21 young normal edentulous subjects under five different conditions: a complete palatal covering, non-covered palate, anterior palatal covering, posterior palatal covering and surface anaesthetized palate. As possible contributory factors palatal morphometric parameters, as well as tongue pressure were also measured. The data were analysed on the following way: changes when the palate was complete covered and non-covered, effects of sensation reduction after topic anaesthesia, effects of differences in the covering site, effects of palatal morphometric parameters and effects of tongue pressure. Ten subjects exhibited significant differences in the propulsion time when comparing the data between the complete palatal covering and the non-covered palate condition (change group). Eleven subjects did not show changes (unchanged group). Effects in the propulsion time were also recognized with posterior palatal covering-palate and superficially anaesthetized palate. With regard to the tongue pressure, significant differences during swallowing were observed. These results indicated that the bolus propulsion time into the oropharynx was affected by the palatal covering in some subjects. Moreover, the sensation in the posterior region of the hard palate, as well as the tongue pressure were also factors which affected the propulsion time during swallowing. [ABSTRACT FROM AUTHOR]