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.

Tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism.

BACKGROUND: Coordination among lip, cheek and tongue movements during swallowing in patients with mandibular prognathism remains unclear. OBJECTIVES: This study aimed to identify the temporal sequences of tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism and compared characteristics with those of healthy volunteers. METHODS: Seven patients with mandibular prognathism (mandibular prognathism group) and 25 healthy volunteers with individual normal occlusion (control group) were recruited. Tongue pressures and masseter, orbicularis oris, mentalis and supra- and infrahyoid muscle activities while swallowing gel were measured simultaneously using a sensor sheet system with five measurement points and surface electromyography, respectively. Onset time, offset time and durations of tongue pressure and muscle activities were analysed. RESULTS: In the mandibular prognathism group, tongue pressure was often produced first in more peripheral parts of the palate. Offset of tongue pressure in the posteromedian and peripheral parts of the palate and maxillofacial muscle activities except for orbicularis oris were delayed. Duration of tongue pressure in the anteromedian part of the palate was significantly shorter and durations of masseter, mentalis and suprahyoid muscle activities were significantly longer. Times to onset of orbicularis oris and suprahyoid muscle activities based on first onset of tongue pressure were significantly shorter. CONCLUSION: These results suggest that patients with mandibular prognathism may exhibit specific patterns of tongue pressure production and maxillofacial muscle activities during swallowing.

Retronasal aroma dynamics related to the swallowing threshold.

BACKGROUND: The state of food comminution caused by chewing is an important factor triggering the swallowing reflex. However, the impact of retronasal aroma released from comminuted food to the nose upon swallowing during food intake is poorly understood. OBJECTIVE: The present study investigated the relationship between aroma concentration and swallowing threshold while chewing a standardised test food. METHODS: Twenty healthy participants took part in this study. Concentration of retronasal aroma was measured over time through the nostrils using an odour sensor. The aroma concentration was measured while chewing an orange-flavoured gummy jelly until swallowing, and the number of chewing strokes was measured to determine the swallowing threshold. Next, the aroma concentration was measured while chewing the gummy jelly for 30 strokes, and 100% and 200% of swallowing threshold without swallowing. The surface area increase in the expectorated gummy jelly pieces was calculated using image analysis and defined as masticatory performance at 30 strokes. RESULTS: The average number of chewing strokes until the swallowing threshold was 45.1 ± 14.2. Higher masticatory performance was associated with a smaller number of chewing strokes at swallowing threshold, and a greater increase in surface area at the swallowing threshold. The number of chewing strokes and the aroma concentration were similar between the swallowing threshold and at the maximum aroma concentration while chewing at 200% of the swallowing threshold. CONCLUSION: The findings suggested that the swallowing threshold might be influenced by retronasal aroma concentration as well as the state of food comminution.

The effects of tongue elevation using a weighted plastic bottle on the tongue pressure and activity of suprahyoid muscles.

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.

Compatibility of two types of gummy jelly tests for detecting decreased masticatory function.

OBJECTIVE: This study aimed to verify the compatibility of masticatory performance tests using different two types of gummy jellies. BACKGROUND DATA DISCUSSING THE PRESENT STATUS OF THE FIELD: Compatibility between the glucose concentration measuring method (GC) and 10-steps visual scoring method (VS), which are masticatory performance tests for diagnosing decreased masticatory function (DMF) in oral hypofunction and the use of different types of gummy jelly, has yet to be confirmed. MATERIALS AND METHODS: The participants consisted of 134 Japanese older people (51 men and 83 women). GC, VS and the increased surface area measuring method (ISA), as an alternative analysis method for VS, were conducted to evaluate masticatory performance. Cohen's Kappa coefficient was used to verify the consistency for detecting DMF between GC and VS. Pearson's correlation coefficient was used to analyse the relationship between GC and ISA. Each masticatory performance was compared among three different groups for the number of residual teeth. Cut-off values of VS and ISA for DMF that were consistent with GC were identified. RESULTS: Glucose concentration measuring method and VS showed an excellent consistency (Kappa coefficient = 0.86). There was a high positive correlation between GC and ISA (r = .70). However, the change in masticatory performance according to the number of teeth was different between GC and VS/ISA. The cut-off values of VS and ISA were a Score of 2 and 1687 mm2 , respectively. CONCLUSION: Glucose concentration measuring method and VS/ISA remained fairly consistent for detecting DMF, which might be useful information to interconnect the various studies on masticatory performance.

Clarification of the aspects of tongue-palate contacts during mastication with/without stage II transport.

BACKGROUND: During mastication, the tongue presses the bolus into the pharynx by a "squeeze-back" motion, known as stage II transport (St2Tr). However, the pressure of St2Tr tongue-palate contact has not been examined. OBJECTIVES: We aimed to clarify aspects of St2Tr occurrence and tongue-palate contact during mastication by measuring tongue pressure. METHODS: Ten healthy adults (eight men, two women, aged 26.8 ± 2.2 years) were enrolled. Tongue pressure was measured (Swallow Scan) during mastication. Sensors were placed on the palate near the incisive papilla (Ch.1), in the middle (Ch.2), at the posterior (Ch.3), and near the first molars on the habitual (Ch.H) and non-habitual (Ch.Nh) masticatory sides. Nasopharyngeal endoscopy confirmed St2Tr and swallowing. Tongue pressures were measured repeatedly, from mastication onset through the first swallow, until eight sets of data were obtained. Tongue-palate contact frequencies, integrated values of tongue pressure, and mastication times were recorded for St2Tr(+) and St2Tr(-) mastication conditions. RESULTS: St2Tr occurred in 43 of 80 trials (53.8%). St2Tr(+) exhibited the highest tongue-palate contact frequency at Ch.H; it exhibited higher contact frequencies at Ch.2, Ch.3 and Ch.H than St2Tr(-). St2Tr(+) exhibited higher tongue pressures at Ch.1, Ch.2 and Ch.H than at Ch.3; it exhibited higher tongue pressures at Ch.1 and Ch.2 than St2Tr(-). CONCLUSION: The study suggested that during St2Tr, the tongue frequently touched the palate at the central and posterior regions, as well as at its habitual masticatory side. It applies the strongest pressure at the anterior and central palate to transport the bolus to the pharynx.

Modulation of tongue motion and tongue pressure during liquid swallowing with different bolus volumes.

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.

Effect of hard gummy candy chewing on masticatory function.

BACKGROUND: Although various training methods have been reported for improving oral function such as occlusal force, there are few reports that show the training effect of eating hard food on the oral functions. OBJECTIVE: To examine the training effects of habitually ating hard gummy candies on oral functions. METHODS: Participants of this cohort study were recruited into a training (six women, eight men; mean age 27.6 ± 3.5 years) and control group (two women, seven men; mean age 28.3 ± 4.9 years). The training group ate nine custom-developed hard gummy candies three times per week for 3 months. Training effects were evaluated by measuring the maximal occlusal force, masticatory performance, maximal tongue pressure, number of chewing cycles until swallowing the candy, duration of chewing and cycle time before training, after 1, 2 and 3 months of training, and 1 month after stopping training. The iEMG/force, which evaluates masseter muscle hypertrophy with electromyograms (EMG), was calculated. RESULTS: Masticatory performance after 1 month (p = 0.01), maximal occlusal force after 2 months (p < 0.01) and maximal tongue pressure after 3 months of training were significantly increased (p = 0.02), and the cycle time after 2 months of training (p = 0.02) was significantly decreased compared to before the intervention. Except for masticatory performance, the other effects were maintained for 1 month after stopping training. Changes in iEMG/force were not significant, but a tendency for muscle hypertrophy was observed in the training group. CONCLUSION: Habitual eating of hard gummy candies is a task-specific training that can improve overall masticatory function, including tongue pressure.

Can masticatory performance be predicted by using food acceptance questionnaire in elderly patients with removable dentures?

BACKGROUND: Although a food acceptance questionnaire is useful for subjective masticatory function assessments, its characteristics and limitations when applied to patients with removable dentures have been unclear. We therefore assessed the relationship between the subjective and objective masticatory function and explored whether or not a decreased masticatory function could be evaluated by food acceptance questionnaire. METHODS: One hundred and nineteen patients >60 years old with removable partial and/or complete dentures participated. Food acceptance score (FAS) was calculated by using Sato's questionnaire with 20 food items. Masticatory performance (MP) was assessed by a visual scoring method using a test gummy jelly (UHA Mikakuto). Simple/multiple regression analyses were performed to explain the objective masticatory function. The cut-off value of FAS was determined to predict a decreased masticatory function by sensitivity, specificity and receiver operating characteristics curve. RESULTS: No significant gender differences in MP or FAS were noted. Although both MP and FAS increased with the number of functional teeth, FAS was not significantly affected by age. The number of functional teeth, FAS and age had significant correlations with MP, with the number of functional teeth showing the strongest correlation. Multiple linear regression analyses identified the FAS as a significant explanatory variable for MP, and 70 was the optimal cut-off value for detecting a decreased masticatory function (MP score ≤ 2) in the diagnosis of 'oral hypofunction'. CONCLUSIONS: Using FAS to assess the MP was deemed appropriate, and a score of 70 was the optimal cut-off value for detecting a decreased masticatory function.

Clinical Oral Disorders in Adults Screening Protocol (CODA-SP) from the 2019 Vancouver IADR Consensus Symposium.

BACKGROUND: The Clinical Oral Disorder in Elders (CODE) index was proposed in 1999 to assess the oral health status and treatment needs of older people who typically were edentate or had few natural teeth. Since then, more people are retaining natural teeth into old age and have oral disorders similar to younger adults. In addition, there has been further guidance on screening for disease that includes changes to the clinical indicators of several oral disorders and greater sensitivity to people's concerns about their oral health and care needs. METHODS: Experts in dental geriatrics assembled at a satellite symposium of the International Association of Dental Research in June 2019 to revise the objectives and content of the CODE index. Before the symposium, 139 registrants were asked for comments on the CODE index, and 11 content experts summarised current evidence and assembled reference lists of relevant information on each indicator. The reference lists provided the base for a narrative review of relevant evidence supplemented by reference tracking and direct searches of selected literature for additional evidence. RESULTS: Analysis of the evidence by consensus of the experts produced the Clinical Oral Disorders in Adults Screening Protocol (CODA-SP). CONCLUSIONS: The CODA-SP encompasses multiple domains of physical and subjective indicators with weighted severity scores. Field tests are required now to validate its effectiveness and utility in oral healthcare services, outcomes and infrastructure.

Factors Influencing Changes in Masticatory Performance as a Result of Wearing Removable Partial Dentures in Patients with Partially Edentulous Arches.

PURPOSE: To measure masticatory performance (MP) in partially edentulous patients when wearing removable partial dentures (RPDs) versus when not wearing RPDs, and to identify factors that could enable clinical evaluations related to differences in MP. MATERIALS AND METHODS: This study consisted of 87 partially edentulous patients (57 females, 30 males; mean age, 69.41 ± 8.85 years) categorized as Eichner classification B who habitually wore RPDs. MP was evaluated while wearing versus while not wearing RPDs using test gummy jellies. The participants were categorized into four groups by the presence of occlusal contacts in one to three of the molar and premolar regions (occlusal support), or in the anterior region only, according to the Eichner index (B1-B4). The participants were also categorized according to the jaw on which the RPDs were worn and the Kennedy classification, and evaluated in regard to changes in MP resulting from wearing RPDs. Additionally, the rate of change in MP (MP-rv) was calculated for each participant using MP when not wearing RPDs as a reference, and factors affecting MP-rv were evaluated using single or multiple regression analysis and the Kruskal-Wallis test with multiple comparisons. RESULTS: Significant increases in MP-rv were observed for all participants and for those with occlusal support in two (p = 0.006) and three regions (p = 0.019); however, no significant differences were observed when wearing and not wearing RPDs in participants with (p = 0.090) and those without occlusal support in one region (p = 0.474). With respect to the jaw on which the RPDs were worn, only maxillary or both maxillary/mandibular RPDs tended to have higher MP-rvs than did only mandibular jaws. The results of the multiple regression analysis showed that Kennedy Class I edentulous arches were a factor in increasing MP-rv (standard partial regression coefficient = 0.46, p < 0.05). CONCLUSION: According to the results of this study, among various factors on the degree of improvement in masticatory performance by wearing RPDs, bilateral missing posterior teeth might be a predictor for achieving clinical improvement.

Coordination between lingual motion and pressure production during dipper/tipper type swallows.

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.

Estimation of pharyngeal residue after swallowing by retronasal aroma.

BACKGROUND: Pharyngeal residue can trigger aspiration and choking after swallowing. Various studies to assess the amount of pharyngeal residue have been conducted; however, an easy and quantitative method is yet to be established. The aroma released from the pharyngeal residue is thought to be delivered from the pharynx to the nasal cavity via velopharynx by expiration, that is, retronasal pathway. OBJECTIVE: This study verified that the amount of pharyngeal residue could be estimated by aroma intensity. METHODS: Ten healthy adult subjects had tubes in from the oral cavity to the pharynx. Varying amounts of essence were dispensed into the pharynx through the tube either at rest or after swallowing the essence. Pharyngeal residue was simulated by retention essence in the pharynx without swallowing. An odour sensor was placed in the nostril, and the aroma intensity of the retained essence was measured over time. RESULTS: The aroma intensity level flattened after a certain period of time had elapsed, and a significant correlation was found between the amount of essence dispensed and the flattened aroma intensity, both at rest and after swallowing. Furthermore, to estimate in a short period of time, changes in aroma intensity over time were estimated by fitting to a decay curve. The estimated intensity at convergence, calculated from the fitted curve from 80 to 120 seconds after swallowing, was significantly correlated to the measured intensity. CONCLUSION: The amount of pharyngeal residue can be estimated in a short period of time by measuring the aroma intensity.

Evaluation of hyoid movement during swallowing using a bend sensor.

BACKGROUND: Movement of the hyoid and laryngeal complex is critical for preventing aspiration, as well as smooth bolus passage through the pharynx. We have developed a non-invasive system for measuring laryngeal movement during swallowing with a bend sensor and have already reported the time coordination between the signal waveform from the sensor and hyoid movement. OBJECTIVE: The aim of this study was to clarify the quantitative association between the output value of the sensor and hyoid movement during swallowing. METHODS: A small bend sensor was fixed on the skin surface along the midline of the neck of 13 healthy men (mean age, 30.8 ± 4.5 years). Laryngeal and hyoid movements during swallowing of 5 mL of water were recorded synchronously by the bend sensor and videofluorography. The relationship between the bend sensor output value (LM value) and hyoid position (x- and y-axis displacements) by videofluorography from the onset to the offset of the signal waveform was analysed for all tasks and for each task using Pearson's correlation coefficients. RESULTS: There was a positive correlation between the LM value and hyoid position for all tasks (x-axis displacement: r = .647, y-axis displacement: r = .233). In particular, there was a moderate to high correlation between the LM value and x-axis displacement for each task (.453 ≤ r ≤ .934). CONCLUSION: The LM value can be a quantitative parameter of anterior hyoid movement during swallowing that might be associated with bolus flow and upper oesophageal sphincter opening.

Tongue Pressure Measurement and Videofluoroscopic Study of Swallowing in Patients with Parkinson's Disease.

This study investigated the relationship between tongue pressure during swallowing and dysphagia in patients with Parkinson's disease (PD). A total of 24 patients with PD (12 men and 12 women, mean age 70.4 years) were studied. Their mean Hoehn and Yahr scale was 3.0 ± 1.3 (range 1-5). All participants underwent tongue pressure measurement and videofluorography during swallowing. Tongue pressure when swallowing 5 mL of barium on videofluorography was measured using a sensor sheet with five sensors. Based on the findings of videofluorography, the patients were divided into two groups: dysphagic PD group (n = 9) and non-dysphagic PD group (n = 15). The maximal magnitude (kPa), duration (s), time to peak pressure (s), and pressure gradient (kPa/s) of tongue pressure were analyzed for each part. For duration, time to peak pressure, and pressure gradient, similar values were calculated from the total waveform. There was no significant difference in maximal tongue pressure between the groups. The dysphagic PD group had prolonged duration of tongue pressure and time to peak pressure and a reduced pressure gradient compared with the non-dysphagic PD group. These results indicate that there is a clear difference in the temporal aspects of tongue pressure between the non-dysphagic and dysphagic PD patients. These differences provide the characteristics of tongue movement during swallowing in PD patients with dysphagia, which may be useful for the diagnosis and treatment of dysphagia.

The effect of tongue thrusting on tongue pressure production during swallowing in adult anterior open bite cases.

BACKGROUND: Tongue thrusting, which often occurs during swallowing in patients with anterior open bite, is considered to show different tongue dynamics from healthy individuals, but the details are still unclear. OBJECTIVE: This study aimed to identify the effect of tongue thrusting on tongue pressure production during swallowing in patients with anterior open bite. METHODS: The subjects were 11 patients with an anterior open bite and 8 healthy volunteers with individual normal occlusion. The patients were divided into a tongue-thrusting group (n = 8) and a non-thrusting group (n = 3). Tongue pressures while swallowing jelly (4 mL) were recorded by a sensor sheet system with five measuring points (Chs1-5) attached to the palatal mucosa. The time sequences, maximum magnitude and duration of tongue pressure, and swallowing time of tongue pressure were analysed. RESULTS: Tongue pressure waveforms in the tongue-thrusting group were quite diverse compared with the other two groups. The duration at the posterior-median part in the tongue-thrusting group was significantly shorter, and the maximum magnitudes at the mid-median, posterior-median and the peripheral part were also significantly lower than in the healthy group. These results suggest that the compensatory tongue thrust action by which the tongue closes the front part of the oral cavity may make it difficult to lift the tongue and transfer the bolus. CONCLUSION: Patients with an anterior open bite and tongue thrusting at swallowing showed diversity of tongue pressure waveforms and noticeably weaker tongue pressures from mid-median to posterior-median regions than healthy individuals.

Tongue Pressure Production and Submental Surface Electromyogram Activities During Tongue-Hold Swallow with Different Holding Positions and Tongue Length.

Our previous study regarding the tongue-hold swallow (THS) demonstrated that the tongue-to-palate contact during THS could be influenced by the maximum tongue protrusion length (MTPL) of individual subjects, resulting in two different patterns of pressure generation. The present study further analyzed the influence of MTPL on the tongue pressure production along with submental surface electromyography (sEMG) during THS, in order to establish an index to better control THS effects. Tongue pressure using a sensor sheet system and concurrent submental sEMG activities were measured during swallowing tasks in 18 healthy young adults. Task conditions comprised THS at two different degrees of tongue protrusion and dry swallow. Tongue pressures and sEMG activities were compared among three task conditions, and correlations of MTPL with tongue pressure were also investigated. Additionally, a ROC curve was used to find a cut-off value for MTPL to predict changes (increases and decreases) in tongue pressure during THS. The duration and the amount of submental muscle activity increased concurrently during THS. Two trends were shown on the change in tongue pressure at the posterior-circumferential part of the hard palate during THS compared to dry swallow; the maximal magnitude and the integrated value of tongue pressure increased in some subjects, while these values decreased in others. Thirty-two millimeters was found to be the cut-off value of MTPL, which distinguishes increase/decrease pattern of tongue pressure with sensitivities of 60.0-85.7%. The present finding suggests that more reliable THS effects should be attainable using MTPL to set the tongue-hold position.

Physical fitness and oral function in community-dwelling older people: a pilot study.

OBJECTIVE: The aim of the present study was to quantify the relation between physical fitness and oral function, including tongue and lip movements. BACKGROUND: Physical fitness and oral function influence quality of life and activities of daily living in older individuals. Occlusal contact and mastication performance are associated with physical fitness, but the association between tongue and lip movements and physical fitness is unclear. MATERIAL AND METHODS: Sixty-six independent community-dwelling older individuals (24 men, 42 women; mean age, 70.3 ± 5.9 years) participated in this study. Measures of physical fitness were the one-leg standing time with eyes open, the functional reach test, anteflexion, the timed up and go test, and grip strength. Measures of oral function were tongue pressure, lip pressure, tongue movement from side to side, the repetitive saliva-swallowing test (RSST), oral diadochokinesis and masticatory efficiency. Multiple regression analysis was used to quantify the relation between physical fitness and oral function. RESULTS: After adjustment for age, sex, BMI, exercise habits and number of remaining teeth, the tongue movement from side to side and/or oral diadochokinesis were chosen as significant factors in each physical fitness measurement. Furthermore, the lip pressure and masticatory efficiency were associated with handgrip strength. CONCLUSION: Oral function, including tongue and lip movements, was associated with physical fitness in older people in this study. Tongue dexterity as characterised by tongue movement from side to side and oral diadochokinesis particularly associated with physical fitness.

Esophageal Involvement in Multiple System Atrophy.

The prevalence of esophageal involvement and its impact on clinical manifestations in patients with multiple system atrophy (MSA) remains unknown. We recruited 16 consecutive patients with dysphagia associated with MSA (MSA group) and 16 consecutive patients with dysphagia associated with amyotrophic lateral sclerosis (ALS group). We assessed the presence or absence of food stagnation within the esophagus using videofluorography. Food stagnation within the esophagus was observed in 16 patients (100 %; 7 severe, 9 mild) in the MSA group and in 4 patients (25 %; 4 mild) in the ALS group (P < 0.001). Follow-up videofluorography revealed that food stagnation in patients with MSA could exacerbate during the disease course. Patients with MSA and severe food stagnation showed a wide range of intraesophageal stasis by videofluorography. Among the 16 patients in the MSA group, 4 developed aspiration pneumonia and 1 died of suffocation associated with food regurgitation during continuous positive airway pressure therapy. In conclusion, food stagnation within the esophagus occurs more frequently in MSA patients with dysphagia than in ALS patients with dysphagia. Because food stagnation can cause serious complications such as aspiration pneumonia and suffocation, patients with MSA should be evaluated by videofluorography, especially those with stagnation in the esophageal phase.

Effect of carbon dioxide in carbonated drinks on linguapalatal swallowing pressure.

This study aimed to investigate the influence of carbonated drinks with gas volumes (GV) of 0, 1.5, and 2.7 on linguapalatal swallowing pressure, intraoral carbonation perception, and maximum velocity of a bolus through the pharynx in healthy volunteers (N = 20, all female, age range; 20-21 years). The volunteers swallowed a 12-mL drink in the natural state. Linguapalatal swallowing pressure was measured using a special sensor sheet, and maximum velocity of the bolus through the pharynx was measured using ultrasonic diagnostic imaging equipment. Peak magnitude, integrated value, and duration of linguapalatal swallowing pressure and maximum velocity of a liquid bolus through the pharynx increased with an increase in carbon dioxide content in the carbonated drink. The total integrated values of carbonated drinks with GV of 1.5 and 2.7 were larger than that of the drink without carbon dioxide. These results suggest that the carbon dioxide dissolved in carbonated drinks influences the activity of taste receptors in the mouth and results in neuromotor responses.