Suprahyoid Research Articles

Effects of Craniocervical Flexion on Suprahyoid and Sternocleidomastoid Muscle Activation in Different Exercises.

This study aims to investigate the effects of craniocervical flexion (CCF) on the activation of suprahyoid and sternocleidomastoid (SCM) muscles in Shaker and Resistant Jaw Opening (RJO) exercises, and to compare the effects of these two exercises on the same muscles with the Chin Tuck Against Resistance (CTAR) exercise. The study recruited a total of 37 healthy participants (20 female and 17 male, mean age: 27.45 ± 7.32years). All participants received craniocervical flexion training with the biofeedback pressure unit (Stabilizer™, Chattanooga Group Inc. USA). Shaker, Shaker with CCF, RJO, RJO with CCF and CTAR exercises were performed and surface electromyographic (sEMG) activations of the suprahyoid and SCM muscles were recorded. In addition, the maximum sEMG activations of suprahyoid and SCM muscles were recorded for the normalization procedure. CCF increased the effect of Shaker exercise on the suprahyoid muscle activation (p < 0.001); but this effect was not seen in RJO exercise (p > 0.05). Suprahyoid muscle activation was lower in Shaker exercise compared to RJO and CTAR exercises (p < 0.016). SCM muscle activation was greater in CTAR exercise compared to Shaker and RJO exercises (p < 0.016). The addition of CCF to the Shaker and RJOE exercises did not affect the ranking among the three exercises for both the suprahyoid and SCM muscles. The result of this study suggest that integration of CCF movement to the Shaker exercise would have a greater therapeutic effect. In addition, RJO exercise can be included in the rehabilitation program as an alternate to CTAR exercise.

Does suprahyoid muscle complex pull cause relapse following genial advancement by distraction osteogenesis? An electromyographic study

Active pull of the suprahyoid muscle complex (SMC) was thought to be the main contributor of relapse in mandibular or chin advancement, but literature evidence lacks human studies that assess the role of the SMC following genial advancement (GeA). This study therefore aimed to analyse the influence of SMC pull on relapse following GeA by distraction osteogenesis based on electromyographic (EMG) changes. EMG was recorded and analysed preoperatively (T0), at four months (T1), and at one-year follow up (T2) at three submental regions during two different activities. The outcome variables were EMG changes of the SMC, and hard and soft tissue relapse. Assessment was carried out by comparison of EMG and lateral cephalograms taken at T0, T1, and T2. Ten patients (7 male and 3 female; median (SD) age 21.2 (3.99) years, range 18-28) were included. The EMG values revealed a statistically significant reduction between T0 and T1. T2 values were not higher than T0 during any activity. The results of Pearson’s correlation demonstrated no significant relation between the amount of relapse and change in EMG values. This study concluded that active pull of the SMC is not the actual reason for skeletal relapse in chin or mandibular advancement. Passive biomechanics such as adnexial or muscular connective tissue, and paramandibular periosteum pull with native bone remodelling might be the prime reasons for relapse. However, further large sample studies are warranted to find the actual causes of relapse.

Ultrasound-guided electroacupuncture at suprahyoid muscle group for pharyngeal dysphagia after stroke: a randomized controlled trial

To compare the effect among ultrasound-guided electroacupuncture (EA) at suprahyoid muscle group, conventional acupuncture and conventional EA at suprahyoid muscle group on pharyngeal dysphagia after stroke, and to explore its biomechanical mechanism. A total of 120 patients with pharyngeal dysphagia after stroke were randomly divided into an observation group, a control-1 group and a control-2 group, 40 cases in each group. The patients in the observation group were treated with ultrasound-guided EA at suprahyoid muscle group; the patients in the control-1 group were treated with EA at Lianquan (CV 23), Wangu (GB 12) and Fengchi (GB 20), etc.; the patients in the control-2 group were treated with EA at suprahyoid muscle group according to anatomical location. The EA in the three groups were discontinuous wave, with frequency of 5 Hz and current intensity of 1 mA. The EA was given for 30 minutes, once a day, 6 times were taken as a course of treatment, and 4 courses of treatment were provided. The video floroscopic swallowing study (VFSS) was performed before and after treatment. The Rosenbek penetration-aspiration scale (PAS) score, the forward and upward movement distance of hyoid bone and thyroid cartilage, Ichiro Fujima ingestion-swallowing function score were recorded in the three groups, and the incidences of subcutaneous hematoma were recorded after treatment. Compared before treatment, the PAS scores were reduced and the Ichiro Fujima ingestion-swallowing function scores were increased after treatment in the three groups (P<0.05); the PAS scores in the observation group were lower than those in the control-1 group and the control-2 group, and the Ichiro Fujima ingestion-swallowing function scores in the observation group were higher than those in the control-1 group and the control-2 group (P<0.05). After treatment, the forward and upward movement distance of hyoid bone and thyroid cartilage in the observation group and the control-2 group was increased (P<0.05), and the forward and upward movement distance of hyoid bone was increased in the control-1 group (P<0.05); the forward and upward movement distance of hyoid bone and thyroid cartilage in the observation group was longer than that in the control-1 group and the control-2 group (P<0.05). The incidence of subcutaneous hematoma in the observation group was 0% (0/40), which was lower than 20.0% (8/40) in the control-1 group and 47.5% (19/40) in the control-2 group (P<0.05). Ultrasound-guided EA at suprahyoid muscle group could improve the swallowing function in patients with pharyngeal dysphagia after stroke by increasing the motion of hyoid laryngeal complex. Its effect and safety are better than conventional acupuncture and conventional EA at suprahyoid muscle group.

A tutorial on articulatory muscles and ArtiSynth: Tongue and suprahyoid muscles, and 3D tongue model

AbstractThis article has two main purposes: (i) to review the placement and function of the tongue and suprahyoid muscles concerning speech articulation, and (ii) as a biomechanical simulation tool to study how those muscles are involved in articulation, to introduce a 3D tongue model distributed by a 3D modelling platform called ArtiSynth. The 3D tongue model can be combined with other structural models to provide the outline of the oral cavity. This article presents examples of muscular simulations for/i/and/ɑ/using the jaw‐hyoid‐tongue model in ArtiSynth.

Reliability of Ultrasound Examination of Hyoid Bone Displacement Amplitude: A Systematic Review and Meta-Analysis.

In swallowing, the hyoid bone moves up and forward in response to the activation of suprahyoid muscles, opening the upper esophageal sphincter and aiding the airway protection mechanism. This displacement measure has been analyzed with ultrasound images because this method does not expose the patient to radiation, has a good cost-benefit ratio, and is safe for the patient. However, there is no consensus on the reliability of this ultrasound measure. The objective of this study was to analyze the reliability of measuring hyoid bone displacement amplitude in swallowing with ultrasound. The systematic review encompassed five databases (MEDLINE, Scopus, EMBASE, Web of Science, Cochrane Library) and gray literature. There was no limitation of language or year of publication. The search/selection/extraction methodology was conducted by two authors blindly and independently, and differences were solved by a third rater. Three studies met the eligibility criteria: two of them analyzed the reliability in non-dysphagic populations and the other, in dysphagic patients. The transducer was positioned in the submandibular region in all studies. The authors were not clear about the training time to acquire and analyze ultrasound images. The meta-analysis had an interrater reliability of 0.858 (95% CI: 0.744-0.924) and intrarater reliability of 0.968 (95% CI: 0.903-0.990). There was, however, heterogeneity of p = 0.005 for intrarater reliability. Despite good reliability, the heterogeneity reinforces the importance of training and protocol standardization for image acquisition and analysis.

Relationship between demographic and cephalometric measures and electromyographic activityu of the facial musculature. A preliminary study in children and adolescents

Surface electromyography (EMGS) is used to evaluate the electromyographic activity of the orofacial musculature at rest, or when performing certain activities such as swallowing saliva or water, or tasks of maximum voluntary contraction. Numerous studies have evaluated the relationship between facial morphology and muscle activity, with contradictory results. The aim of this study was to determine whether there are significant differences in the electromyographic activity of the orofacial musculature as a function of the variables: age, height, weight, facial pattern and skeletal class. For this purpose, 81 patients with dental malocclusion were selected (35 males and 46 females, aged 6 to 17 years). Bilateral EMGS activity of the temporalis, masseter, orbicularis oris of the upper and lower lip of the mouth and suprahyoid muscles was measured in the resting position, maximum voluntary contraction and swallowing of saliva 2 ml of water. The results obtained show that the mandibular plane and the ANB angle present significant differences in all the variables of EMGS activity; however, the facial pattern only shows significant differences in the mean deviation of muscle activity. Skeletal class shows no significant effect on any of the EMGS variables recorded. The variables Age, Weight and Height show significant results on all EMGS activity variables. The variable Sex only shows significant results in the mean deviation of muscle activity. This work supports previous studies that found no significant results based on facial pattern and skeletal class. It would be advisable to perform a more exhaustive analysis of the muscles involved and their relationship between the different tasks evaluated, and to increase the sample size of patients with skeletal Class III in order to reach more definitive conclusions.

Effects of a tongue training program in Parkinson's disease: Analysis of electrical activity and strength of suprahyoid muscles

ObjectiveTo assess the electrical activity of the suprahyoid muscle and the tongue pressure in a two-wing program of tongue strengthening in individuals with Parkinson's disease (PD). MethodsA pre-post-detraining design study included sixty PD patients assigned to two groups randomly. The experimental group (EG) performed tongue isometric pressure exercises using the Iowa Oral Performance Instrument with an increasing scheme of 5% load weekly and traditional tongue therapy for 8 weeks. The control group (CG) performed only traditional therapy. The electrical activity of suprahyoids was measured using surface electromyography (sEMG) during tongue-to-palate pressure. Four selected domains of the Swallowing Quality of Life Questionnaire (SWAL-QOL) mostly related to tongue strength were considered. ResultsThe experimental group showed increased sEMG values of suprahyoid muscles reaching statistically significant difference at the fourth week of tongue training, while the control did it at the eighth week. Experimental group showed significant improvements in tongue strength (d = 2.128; p = 0.000). Only controls showed detraining effect. Statistically significant difference within groups were found in one and three dimensions of the SWAL-QOL in the CG and EG, respectively. ConclusionAnalysis of electrical activity on suprahyoids muscles provided a better understanding of the changes underlying the outcomes of tongue strength gains obtained through a combined tongue strengthening exercises protocol in PD. Such protocol led not only to increased tongue strength but also to a better perceived swallowing function in PD subjects.

Reliability and validity of ultrasound to measure of muscle mass following allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients frequently show physical dysfunction due to loss of muscle mass. This study aimed to clarify the reliability and validity of ultrasound in evaluating muscle mass and to analyze the patterns of change in muscle mass before and after allo-HSCT. We conducted a prospective observational study using data from 68 patients who had undergone their first allo-HSCT. We evaluated the thickness of the quadriceps, biceps, and suprahyoid muscle. Three individual evaluators underwent this examination for each muscle before transplantation and on days 30, 90, and 180 after allo-HSCT. Inter-rater reliability was calculated using the interclass correlation (ICC), and the level of correlation between muscle mass measured by ultrasound and psoas muscle mass assessed using computed tomography (CT) was assessed using Pearson correlation. ICC values ranged from 0.897 to 0.977 in the measurement. The correlation scores were 0.730, 0.546 and 0.579 between psoas muscle and the biceps, quadriceps, and suprahyoid muscle. The thickness of the biceps and quadriceps muscle were both significantly decreased after allo-HSCT from baseline. These results showed that the ultrasound technique was a reliable tool for evaluating muscle mass and detecting changes in muscle mass following allo-HSCT.

Detection of swallowing disorders with a multiple-channel surface electromyography sensor sheet

Background/purposeA sensor sheet comprising multiple electromyography electrodes that can be used to measure a series of multiple muscle activities related to swallowing was recently developed. In this study, we aimed to evaluate its utility in detecting swallowing disorders with a new method for the identification of muscle activity. Materials and methodsAll participants were evaluated by using the repetitive saliva swallowing test and modified water swallowing test and were classified accordingly into participants with (n = 21; mean age, 81.6 [standard deviation, 10.1] years) and those without (n = 41; mean age, 70.0 [8.4] years) dysphagia. The sheet contains four pairs of electrodes, and surface electromyography (sEMG) was performed on the suprahyoid (position A: upper front of the suprahyoid muscles; position B: bottom rear of the suprahyoid muscles) and infrahyoid (position C: above the infrahyoid muscles; position D: beneath the infrahyoid muscles) muscles while the participants swallowed liquid, thickened water, paste, and jelly. The sEMG findings, including the duration of swallowing waveforms and the delay in swallowing onset from position A to positions B, C, and D, were compared between the groups. ResultsThe duration of muscle activity differed between the groups in the infrahyoid muscles when jelly (Mann–Whitney U test; position C, P = 0.007 and position D, P = 0.018) and thickened water (position C, P = 0.033) were swallowed. ConclusionOur study demonstrates the utility of a novel sensor sheet developed for detecting swallowing disorders by using visual methods for identification of muscle activity.

Fonoaudiologia em estética da face: efeito de duas estratégias para musculatura supra-hioidea

ABSTRACT Purpose: to verify the effects of tongue pressure exercises against the incisive papilla, used both alone and in combination with functional swallowing training, on the electrical activity of the suprahyoid muscles and the self-perception of aesthetic changes in the submandibular region. Chi-square, Fisher’s exact, Mann-Whitney, Kruskal Wallis, and Wilcoxon tests were used. The significance level was set at 5%. Methods: an experimental, analytical, prospective study on 27 women, aged 30 to 78 years, divided into two treatment groups (G1 and G2), and a control group (CG). Individuals were submitted to 8 weeks of training, in which G1 performed only tongue pressure exercises against the incisive papilla, and G2 performed the same exercises in combination with swallowing training, while CG was not submitted to any intervention. The suprahyoid muscle electrical activity was obtained with surface electromyography at the beginning and end of the study when subjects also answered a self-perception questionnaire on possible aesthetic results. Pearson’s chi-square, Fisher’s exact, Mann-Whitney, Kruskal Wallis, and Wilcoxon tests were used. The significance level was set at 5%. Results: statistically significant differences were found between the initial and final electrical activity in both G1 and G2, which was not found in CG. There was no significant difference between the groups regarding their self-perception of visual or muscle improvements. Conclusion: both strategies analyzed were equally effective to increase suprahyoid muscle recruitment, though with no impact on the self-perception of aesthetic changes in the submandibular region.

3D Vector Reconstruction of the Muscles of the Ventral Region of the Neck from Anatomical Sections of Korean Visible Human at the Paris Descartes Anatomy Laboratory

Objective: To carry out a 3D vector reconstruction of the muscles of the ventral region of the neck from anatomical sections of the “Korean Visible Human” for educational purposes. Materials and Methods: The anatomical subject was a 33-year-old Korean man who died of leukemia. He was 164 cm tall and weighed 55 kgs. The anatomical sections were made in 2010 after an MRI and a CT scan. A special saw (cryomacrotome) made it possible to make cuts 0.2 mm thick on the frozen body, i.e. 5960 cuts. Sections numbered 1500 to 2000 (or 500 cuts covering the neck) were used for our study. A segmentation by manual contouring of each anatomical element of the anterior neck region was done using Winsurf version 3.5 software on a laptop PC running Windows 7 equipped with an 8 gigabyte RAM. Results: We modeled the sternocleidomastoid muscles, the supra-hyoid muscles, the infra-hyoid muscles and the muscle structures of the anterior neck region, the aero-digestive axis of the anterior neck region and the vasculo-nervous axis of the neck. This model is easily manipulated using the Acrobat 3Dpdf interface. Each item accessible in a menu can be displayed, hidden or made transparent, and 3D labels are available as well as educational menus for learning anatomy. This vector model has been integrated into the Diva3d virtual dissection table, a new educational tool used by universities and medical schools to learn anatomy. This model was also uploaded to the Sketchfab? website and 3D printed using an ENDER? pro 3 printer. Conclusion: This original work constitutes a remarkable educational tool for the anatomical study of the anterior neck region and can also be used as a 3D atlas for simulation purposes for training in therapeutic gestures.

Examination of surface electrode placement site for suprahyoid muscle stimulation

Examination of surface electrode placement site for suprahyoid muscle stimulation

Speech pathology in facial aesthetics: effects of two strategies for the suprahyoid muscles

RESUMO Objetivo: verificar os efeitos do exercício de pressão de língua contra a papila incisiva, realizado de forma isolada e associada ao treino funcional da deglutição, na atividade elétrica da musculatura supra-hioidea e na autopercepção da mudança estética na região submandibular. Métodos: estudo experimental, analítico e prospectivo, realizado com 27 mulheres entre 30 e 78 anos, divididas em dois grupos de tratamento (G1 e G2) e um grupo controle (GC). Os indivíduos foram submetidos a oito semanas de treinamento, sendo que o G1 realizou somente o exercício pressão de língua contra a papila incisiva, o G2 realizou o mesmo exercício associado ao treino da deglutição e o GC não foi submetido a qualquer intervenção. A atividade elétrica da musculatura supra-hioidea foi obtida por meio da eletromiografia de superfície no início e ao final do estudo, quando também foi aplicado um questionário de autopercepção dos possíveis resultados estéticos obtidos. Foram utilizados os testes Qui-quadrado de Pearson, Exato de Fisher, Mann Whitney, Kruskal Wallis e Wilcoxon, com nível de significância de 5%. Resultados: foram encontradas diferenças estatisticamente significativas na atividade elétrica entre os valores inicial e final tanto no G1 quanto no G2, fato não observado no GC. Não houve diferença significativa entre os grupos em relação à autopercepção da melhora visual e da melhora muscular. Conclusão: as duas estratégias analisadas mostraram-se igualmente eficazes para promover o maior recrutamento da musculatura supra-hioidea, porém, sem impacto na autopercepção da mudança estética na região submandibular.

Surface Electromyography Quantification Methods for Evaluating Muscle Activity in Dysphagia

Quantitative evaluation of stroke patients with the risk of swallowing disorder or dysphagia is required to support diagnosis and further rehabilitation planning. Fluoroscopy X-ray imaging usually is used for swallowing diagnosis, though it gives radiation exposure to patients. Therefore, quantification of muscle coordination patterns involved in swallowing based on surface electromyography (sEMG) was introduced. However, an adequate quantification of sEMG for dysphagia diagnosis still lacks standardization. In this work, potential sEMG signal features, namely the contraction duration (DUR), the time to peak of maximum contraction (TTP), and the total RMS power (TP), were further investigated to evaluate the swallowing processes in healthy subjects and post-stroke patients. The experimental scheme instructed the participant, i.e. 20 healthy subjects and 20 patients, to swallow 3 mL of water in normal swallowing mode and swallow saliva in dry swallowing mode. The proposed signal processing procedure helps to establish the feature extraction of the three features mentioned earlier. For dysphagia assessment, with the support of our proposed signal processing procedure, DUR and TTP can be used together to improve diagnosis reliability. The characteristic of both features in healthy subjects was shorter than in post-stroke patients. Also, the TP feature is useful as additional information to evaluate the role of suprahyoid (SUP) and infrahyoid (INF) muscle groups which are very important in the swallowing process. These results are promising to provide a reliable set of features in the time domain for swallowing analysis. Notably, this can also be utilized as a feature for supporting the automatic classification of dysphagia diagnosis.

Will Suprahyoid Muscle Release be Effective to Improve Swallowing in Patients with Temporomandibular Disorders? A Single Group Experimental Study

Background: As for jaw opening force, hyoid resting position and hyoid dynam­ics are very important and are considered to be affected directly by the suprahyoid muscles. MFR is found to be effective in giving symptomatic relief and increasing jaw ROM in patients with myofascial TMD. The study will specify the importance of Suprahyoid MFR in improving swallowing &amp; jaw function in TMD.&#x0D; Objectives: The study aimed at finding out the effectiveness of suprahyoid muscle MFR on swallowing and jaw function in patients with TMD.&#x0D; Methods: 20 participants with myogenous TMD were included after fulfilling the selection criteria. Treatment strategies involved MFR to suprahyoid muscle for 3 sessions in a week for one week and home exercise program involving the tongue proprioception exercises. The outcome measures were evaluated through Sydney swallowing questionnaire (SSQ-17), LDF-TMD questionnaire and maximal interincisal opening (IIO). The data was analysed and inference was drawn through paired and unpaired t tests.&#x0D; Results: The result of the present study showed that participants improved significantly (p &lt;0.05) at post one week on all the outcome measures (IIO, SSQ &amp; LDF-TMD).&#x0D; Conclusion: This study demonstrated that suprahyoid release is effective in improving swallowing in patients with TMD.

The effect of Kinesio Taping on drooling in children with intellectual disability: A double-blind randomized controlled study

PurposeDrooling is an unintentional spillage of saliva, which can be caused by any condition that affects the neuromuscular control of mouth muscles. There are different treatments for drooling, some of which are novel therapies with unknown efficacy like Kinesio Taping (KT). This study aimed to investigate the effects of adding KT to oral-motor training (OMT) on drooling in children with intellectual disability. MethodThis is a double-blind randomized controlled trial in which 18 children with intellectual disabilities participated through convenience sampling. Participants were randomly assigned into 2 groups by block randomization method. Kinesio taping of orbicularis oris, supra-hyoid and masseter muscles and routine OMT were performed for the intervention group. The control group received taping with no stretch as placebo. Pre-post assessment was carried out after four weeks of intervention by the drooling rating scale (DRS) and drooling quotient (DQ) test. ResultsWithin-group analysis showed a significant reduction in drooling post-intervention in both groups based on DRS and DQ (p < 0.001). Between-group analysis indicated a significant improvement in the intervention group (P = 0.008) with moderate effect size using DQ assessment but this difference was not significant with moderate effect size based on parental reports using DRS. ConclusionDQ assessment revealed that using KT plus OMT can produce greater improvement than sham taping plus OMT. However, there was not a statistically difference between the two groups based on parental reports using DRS. In addition, within-group analysis showed that drooling reduced in both groups after the intervention both based on DRS and DQ assessments. It can be concluded that adding taping with and without stretch to OMT can be considered as a complementary method to mitigate drooling in children with intellectual disabilities.

Brow and Masticatory Muscle Activity Senses Subjective Hedonic Experiences during Food Consumption.

Sensing subjective hedonic or emotional experiences during eating using physiological activity is practically and theoretically important. A recent psychophysiological study has reported that facial electromyography (EMG) measured from the corrugator supercilii muscles was negatively associated with hedonic ratings, including liking, wanting, and valence, during the consumption of solid foods. However, the study protocol prevented participants from natural mastication (crushing of food between the teeth) during physiological data acquisition, which could hide associations between hedonic experiences and masticatory muscle activity during natural eating. We investigated this issue by assessing participants’ subjective ratings (liking, wanting, valence, and arousal) and recording physiological measures, including EMG of the corrugator supercilii, zygomatic major, masseter, and suprahyoid muscles while they consumed gel-type solid foods (water-based gellan gum jellies) of diverse flavors. Ratings of liking, wanting, and valence were negatively correlated with corrugator supercilii EMG and positively correlated with masseter and suprahyoid EMG. These findings imply that subjective hedonic experiences during food consumption can be sensed using EMG signals from the brow and masticatory muscles.

Factors Affecting the Swallowing Dysfunction Following Oral Cancer Surgery.

ObjectiveTo investigate the factors affecting the postoperative swallowing dysfunction in patients who underwent oral cancer surgery.MethodsRetrospective review of clinical records of 70 patients (50 males and 20 females) who underwent oral cancer surgeries from July 2007 to April 2015 were enrolled. Multiple regression analysis was performed using the Food Intake LEVEL Scale (FILS) at discharge as the objective variable and age, tumor size, resection of the tongue base, suprahyoid muscle resection, segmental mandibulectomy, neck dissection and radiation therapy as the explanatory variables in 70 patients. In addition, multiple regression analysis was performed between objective variables, which include maximum hyoid bone movement, laryngeal elevation delay time, pharyngeal constriction ratio (PCR), residue in the vallecular and pear-shaped depression (pyriform sinuses), and Penetration-Aspiration Scale score and one of the main factors representing the characteristics of each case as the explanatory variables, and age was treated as an adjustment factor in 23 patients.ResultsThe FILS shows significant negative correlation by age and resection of the tongue base. In videofluoroscopic swallowing study, the maximum movement, PCR and residue in the vallecular are significantly correlated with factors demonstrating the characteristic for each case.ConclusionIt was suggested that in elderly patients, the presence of more than half of the tongue base resection, suprahyoid muscle resection and neck dissection cause severe dysphagia after surgery.

Tongue cleaning in the elderly and its role in the respiratory and swallowing functions: Benefits and medical perspectives.

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.

Textural properties and muscle activities during mastication of normal and ultrasonically softened sticky rice aimed for consumers with swallowing disorder: A pilot study.

Ultrasonication was used to develop softer sticky rice for elder adults. Textural properties of original sticky rice (oSR) and ultrasonically modified sticky rice (mSR) were determined. In addition, jaw muscle activities during mastication of both oSR and mSR were investigated. Twenty-seven healthy elderly subjects, age 68.9 ± 7.6 years, were asked to masticate both types of sticky rice in random sequence for three times with a 5-min rest between each test. Activities of bilateral masseter and suprahyoid muscles were recorded. Root mean square (RMS) and mastication duration were analyzed. After mastication trials, subjects were asked to rate preference and softness of the samples. mSR exhibited significantly lower hardness than oSR, while cohesiveness and adhesiveness values of the two samples were not significantly different. Interestingly, all the muscle activities were not significantly different between masticating oSR and mSR, whereas the number of chewing cycles while chewing the mSR was larger. However, 92% of the subjects preferred mSR and felt that it was softer. mSR may therefore be regarded as having potential for elder people who have difficulty masticating hard solid foods based on its lower hardness and higher level of preference compared to oSR.