Tongue Press Research Articles

Functional MRI during tongue strength tasks before and after partial glossectomy: Insights into the cortical activation of tongue motor function.

Because the tongue is a midline structure, studies on the neural correlates of lateralized tongue function are challenging and remain limited. Patients with tongue cancer who undergo unilateral partial glossectomy may be a unique cohort to study tongue-associated cortical activation, particularly regarding brain hemispheric lateralization. This longitudinal functional magnetic resonance imaging (fMRI) study investigated cortical activation changes for three tongue tasks before and after left-sided partial glossectomy in patients with squamous cell carcinoma of the tongue. Seven patients with squamous cell carcinoma involving the left tongue who underwent fMRI before and 6months after unilateral partial glossectomy were studied. Post-surgical changes in laterality index (LI) values for tongue-associated precentral and postcentral gyri fMRI activation were calculated for the dry swallow, tongue press, and saliva sucking tasks. Group analysis fMRI activation maps were generated for each of the three tasks. There were significant differences in changes in LI values post-surgery between the tongue press (p < 0.005; median: +0.24), saliva sucking (-0.10), and dry swallow tasks (-0.16). Decreased contralateral activation (change in LI ≥+0.20) was observed post-surgery during tongue press in six of seven patients, but only in two patients during saliva sucking and one patient during dry swallow (p < 0.05). There was also increased activation in the supplementary motor area following surgery. Post-surgical fMRI changes following left-sided partial glossectomy may suggest task-specific sensitivities to cortical activation changes following unilateral tongue deficits that may reflect the impacts of surgery and adaptive responses to tongue impairment.

Comparison of three different types of exercises for selective contractions of supra- and infrahyoid muscles

Several exercise methods, such as the Shaker exercise, tongue press exercise, chin tuck against resistance (CTAR) exercise, and submandibular push exercise, have been introduced to strengthen the muscles involved in swallowing. In this study, we compared the effectiveness of the CTAR, submandibular push, and Shaker exercises for the induction of selective supra- and infrahyoid muscle contractions using surface electromyography (EMG). This study is a prospective non-randomized controlled study. Twenty-five healthy subjects and 20 patients experiencing swallowing difficulty were enrolled. During the three different types of exercises, the root mean square (RMS) values of the sternocleidomastoid (SCM), suprahyoid (anterior belly of the digastric and mylohyoid muscles), and infrahyoid (sternothyroid and thyrohyoid muscles) muscles were analyzed using surface EMG. Differences in the activity of swallowing muscles among the three different exercises were analyzed using one-way repeated measured analysis of variance. In terms of both the maximum and mean RMS values of the suprahyoid muscle, the submandibular push exercise showed a larger RMS value than the CTAR and Shaker exercises in healthy subjects (p < 0.05). In terms of both the maximum and mean RMS values of the suprahyoid muscle, the Shaker exercise and submandibular push exercise showed a larger RMS value than the CTAR exercise in patients with swallowing difficulty (p < 0.05). The submandibular push exercise may be effective as a swallowing muscle exercise owing to its superiority in inducing selective contractions of the supra- and infrahyoid muscles. The CTAR and Shaker exercises are also effective in this regard.

Effects of Effortful Swallowing Exercise with Progressive Anterior Tongue Press Using Iowa Oral Performance Instrument (IOPI) on the Strength of Swallowing-Related Muscles in the Elderly: A Preliminary Study.

The purpose of this study was to confirm the effect of effortful swallowing (ES) exercise programs applied to increase the swallowing-related muscle strength in the elderly. In this study, 20 healthy elderly people (76.65 ± 5.87years; 10 women and 10 men) participated and exercised for 7weeks. The experimental group performed ES exercise combined with external resistance using Iowa Oral Performance Instrument (IOPI), and the control group performed pure ES without external resistance. The exercises were performed for 20min a day, 2days a week for 7weeks in both groups. ES was repeated 60 times in weeks 1 and 2, 80 times in week 3 and 4, and 120 times in weeks 5-7. In the experimental group, the isometric and swallowing tongue pressures at week 8 were significantly improved compared to baseline. At week 8, the anterior and swallowing tongue pressures and anterior tongue endurance were significantly higher than those of the control group. In the control group, no significant change in tongue pressure-related variables was observed after 7weeks of exercise. ES exercise combined with IOPI resistance for 7weeks tended to increase the suprahyoid muscle activation level without statistical significance. For clinical application of this exercise protocol, further studies including more elderly people and patients with dysphagia are required.

Functional characterization of extrinsic tongue muscles in the Pink1-/- rat model of Parkinson disease.

Parkinson disease (PD) is associated with speech and swallowing difficulties likely due to pathology in widespread brain and nervous system regions. In post-mortem studies of PD, pathology has been reported in pharyngeal and laryngeal nerves and muscles. However, it is unknown whether PD is associated with neuromuscular changes in the tongue. Prior work in a rat model of PD (Pink1-/-) showed oromotor and swallowing deficits in the premanifest stage which suggested sensorimotor impairments of these functions. The present study tested the hypothesis that Pink1-/- rats show altered tongue function coinciding with neuromuscular differences within tongue muscles compared to wildtype (WT). Male Pink1-/- and WT rats underwent behavioral tongue function assays at 4 and 6 months of age (n = 7-8 rats per group), which are time points early in the disease. At 6 months, genioglossus (GG) and styloglossus (SG) muscles were analyzed for myosin heavy chain isoforms (MyHC), α-synuclein levels, myofiber size, centrally nucleated myofibers, and neuromuscular junction (NMJ) innervation. Pink1-/- showed greater tongue press force variability, and greater tongue press forces and rates as compared to WT. Additionally, Pink1-/- showed relative increases of MyHC 2a in SG, but typical MyHC profiles in GG. Western blots revealed Pink1-/- had more α-synuclein protein than WT in GG, but not in SG. There were no differences between Pink1-/- and WT in myofiber size, centrally-nucleated myofibers, or NMJ innervation. α-synuclein protein was observed in nerves, NMJ, and vessels in both genotypes. Findings at these early disease stages suggest small changes or no changes in several peripheral biological measures, and intact motor innervation of tongue muscles. Future work should evaluate these measures at later disease stages to determine when robust pathological peripheral change contributes to functional change, and what CNS deficits cause behavioral changes. Understanding how PD affects central and peripheral mechanisms will help determine therapy targets for speech and swallowing disorders.

A novel method to quantitatively evaluate slipperiness and frictional forces of solid oral dosage forms and to correlate these parameters with ease of swallowing

Patient adherence to oral solid dosage forms depends majorly on the ease of swallowing of these formulations. Conventional methods of evaluating this property is not reflective of the actual scenario as endogenous factors, such as adhesion to the mucus membranes from the oral cavity to the stomach, are not considered. Therefore, we developed a novel method based on the use of a creep meter to measure frictional resistance between various dosage forms and artificial skin as physical properties related to the ease of swallowing formulations. First, the sample was subjected to load (0.5 N for 5 s) from the top, corresponding to tongue press. Next, the sample was moved in the horizontal direction at a speed of 1 mm/s while keeping the vertical load, and the frictional force generated between the artificial skin of the plunger and the sample surface was measured for 15 s. The frictional force was measured under dry conditions and after the sample was immersed in water. According to the novel in vitro evaluation method of slipperiness developed in this study, it is possible to design a slippery and easy-to-swallow formulation that could contribute to improved patient adherence.

Age-Related Differences in Pressures Generated During Isometric Presses and Swallows by Healthy Adults.

The aim of this prospective observational study was to determine the associations among age, maximum lingual isometric pressures, and maximum swallow pressures in specific regions of the tongue. Individuals 21 years and older who reported normal swallowing were enrolled. Seventy-one healthy adults were stratified by age into young (21-40years), middle (41-60), and old (61-82) groups. Maximum pressures were measured for each individual during isometric tongue press tasks as well as saliva, 5, and 10mL thin liquid bolus swallows at 5 sensors located on the hard palate: front, middle, left, right, and back. Lower maximum lingual pressures for all tasks were associated with increased age (p<0.04). Saliva pressures exhibited a different pressure pattern than bolus swallows with pressures higher than bolus swallows on middle (p<0.03) and back (p<0.05) tongue sensors but not in the front. Diminished swallow pressure reserve (maximum isometric pressure-maximum swallow pressure) also was found with increased age (p<0.03). Isometric pressures were greater than swallow pressures in young and middle age groups at both the front (p<0.04) and back (p<0.03) sensors, but only significantly greater at the front sensor for the oldest group (p<0.04). Older healthy adults have lower lingual isometric pressures and lower swallow pressures than younger healthy adults. Elders have a decreased swallow pressure reserve to draw upon during occasions of physiological stress. While the exact mechanisms for age-related decline in lingual pressures remain unclear, they are likely due, at least in part, to sarcopenia. Saliva, 5, and 10mL thin boluses also exhibit different age-related declines in pressure at specific sensors, indicating they may elicit different muscle activation patterns.

Comparison of Maximal Lingual Pressure Generation During Isometric Gross and Fine Sensorimotor Tasks in Healthy Adults

ObjectivesTo (1) compare 2 distinct isometric lingual press tasks, fine sensorimotor versus gross sensorimotor, at multiple sensor locations in relation to age and sex; and (2) provide a normative data set using a lingual-strengthening device. DesignCohort study. SettingUniversity. ParticipantsHealthy men and women (N=71; age range, 21–82y) recruited from the community. InterventionsParticipants were stratified by age and sex and divided into 3 age groups. Participants completed, in random order, 2 isometric tasks: (1) fine sensorimotor: tongue press maximally and discreetly against each of 5 sensors; and (2) gross sensorimotor: tongue press maximally against all 5 sensors simultaneously. Main Outcome MeasuresPrimary outcome was maximum isometric pressure in hectopascals (hPa). Secondary outcomes were time to reach peak pressure (s) and pressure gradient (hPa/s). ResultsMaximum pressures were significantly lower in those of older age for both fine and gross sensorimotor lingual tasks (P<.01), with the front and back sensors showing the greatest decline (35% and 45%, respectively). Pressure differences between tasks (P=.0012) resulted in the fine sensorimotor task generating higher pressures at the front sensor for all age groups. However, the gross sensorimotor task generated faster maximum pressures at all sensor locations for all age groups. For both sensorimotor tasks, subjects of older age as a whole generated less steep pressure gradients (P<.001). ConclusionsAge-related decline in tongue strength is greater at the anterior and posterior tongue. Results indicate a simpler gross sensorimotor task may be more beneficial for targeting timing as a biomechanical parameter during therapy, and the fine sensorimotor task may be more beneficial for targeting strength.

The effect of age and tongue exercise on BDNF and TrkB in the hypoglossal nucleus of rats

Age-associated changes in tongue musculature may contribute to dysphagia. One possible treatment is tongue exercise. Exercise induces synaptic plasticity by increasing neurotrophic factors in spinal cord and limb musculature. However, effects of exercise on neurotrophic factors in the cranial sensorimotor system are unknown. Our purpose was to examine the effects of age and exercise on brain-derived neurotrophic factor (BDNF) and its receptor TrkB in the rat hypoglossal nucleus. Young, middle-aged, and old rats were assigned to exercise or no-exercise control conditions. Exercise animals were trained to perform a tongue press task for 8 weeks. Samples from the hypoglossal nucleus were analyzed for BDNF and TrkB immunoreactivity. Baseline maximum tongue forces were similar in all age groups and increased significantly following exercise. BDNF immunoreactivity did not show a significant decrease with age in control group. However, in the exercise group, BDNF was significantly increased in young animals. TrkB immunoreactivity decreased significantly with age in control group, but did not change with exercise. BDNF and TrkB immunoreactivity levels were positively correlated with exercise in young and middle aged animals, but were negatively or weakly correlated with exercise in old animals and with a lack of exercise in no-exercise controls. Tongue exercise was associated with increased tongue forces in rats at all ages. While increases in BDNF and TrkB levels associated with exercise may play a role in mechanisms contributing to increased tongue forces in young and middle-aged rats, other mechanisms may be involved in increased tongue forces observed in old rats.

Dopaminergic influence on rat tongue function and limb movement initiation.

Altering dopamine synaptic transmission can affect both cranial and limb sensorimotor function, but often to a different degree of severity. We hypothesized that haloperidol has dose-dependent but differential effects on lingual forces, lingual movement rates, and limb movement initiation. We measured average and maximal lingual force, tongue press rate and cataleptic descent time in nine Fischer 344/Brown Norway rats in varied doses of haloperidol. Decreases in lingual force and temporal parameters and increases in cataleptic descent time were related to haloperidol dose. However, they were related to a different degree as the relationships were strong between average force and tongue press rate, moderate between maximal force and tongue press rate, moderate between average force and cataleptic descent time, and weak between maximal force and cataleptic descent time. Elucidating the relationships between the cranial and limb sensorimotor systems in the context of altered dopamine synaptic transmission may assist in developing therapies for conditions such as Parkinson's disease.

The relationship between lingual‐palatal pressures and submental surface electromyographic signals

This study investigated the relationship between lingual-palatal pressures and submental surface electromyographic (sEMG) signals. During isometric and isotonic tongue press tasks, lingual-palatal pressures from the anterior, middle and posterior hard palate and submental sEMG signals were recorded. Peak values of both tasks and mean values of the isotonic task were analyzed using Pearson's correlations. The correlations ranged from slightly negative (r = -0.103) between the posterior tongue bulb and sEMG peaks in the isotonic condition, to positive (r = 0.360) between the posterior tongue bulb and sEMG peaks in the isometric condition. None of the correlations were statistically significant. Overall, the correlations between submental sEMG signals and lingual-palatal pressures were low. These results suggest that sEMG signals obtained from the submental region measure some of muscle activation during tongue press tasks, but are unable to capture discrete variations in lingual-palatal pressure.

Waking‐state oral parafunctional behaviors: specificity and validity as assessed by electromyography

In contrast to sleep-related oral parafunctional behaviors, little is known about waking oral parafunctional behaviors. The Oral Behaviors Checklist contains terms referring to a variety of non-observable behaviors that are reliable when prompted (e.g. 'clench') but validity data are absent. Our goal was to assess whether (i) each behavioral term is distinct electromyographically, and (ii) temporomandibular disorder (TMD) subjects differ from non-TMD subjects in their performance. Surface electromyographic (EMG) activity was used to measure bilateral masseter, temporalis, and suprahyoid muscles while subjects (27 patients with TMD; 27 healthy controls) performed ten oral behaviors without explanation. Electromyographic data were averaged between bilateral muscles and two trials. A multivariate construct (jaw muscle activity) was analyzed using Wilks lambda within multivariate analysis of variance (manova). Obvious behaviors (e.g. clench, read, tongue press) exhibited expected EMG patterns, and patients and controls produced identical profile plots of the EMG data. Of 10 tested behaviors, nine were found to be associated with significantly differing proportions of amplitudes across muscles and were thus unique. Behaviors with similar terms were associated with different EMG patterns. The present data support the specificity of behavioral terms and performances. Implications include causation related to TMD based on subtle behaviors that occur at a high frequency.

Comparison of surface electromyographic (sEMG) activity of submental muscles between the head lift and tongue press exercises as a therapeutic exercise for pharyngeal dysphagia

The present study compared surface electromyographic (sEMG) activity obtained from the submental muscle group for a tongue press and a head lift exercise as potential therapeutic exercises for dysphagic elderly. Fifty-three healthy volunteers with a mean age of 35.3 participated in this study. Subjects were required to perform an isometric task, pressing their tongue against the hard palate, and an isotonic task requiring sustained lingual force against the hard palate. Pressure sensors were used to measure the amount of lingual pressure against the hard palate. Submental sEMG data from these tasks were compared with those obtained from the isometric and isotonic aspects of a head lift exercise. No sEMG differences were identified between the isometric tongue press task and head lift exercise. Isotonic tongue press exercises resulted in significantly higher maximum and mean sEMG values compared with the isotonic head lift exercise (p < 0.05). The submental sEMG activity from the tongue press exercise was equal (isometric) to, or greater (isotonic) than comparable muscle activation obtained during the head lift exercise. The tongue press exercise may be less strenuous than the head lift exercise while achieving the same therapeutic effect.

上下顎同時印象による総義歯の臨床

Swallowing is the most important movement in the oral cavity as an inret of nutrition essential to the maintenance of the human life. At that time, patients wearing full dentures due to edentulous jaw have comparable movements to those observed in the dentulous jaw. Namely, the tongue press its tip against the rugae of palate in the first stage of swallowing, and then gradually establishes contact between its back and the posterior portion of palate with pressure to transport the food into the pharynx. During this couse, the contact of the posterior portion of tongue with dentures plays an important role in stabilization of dentures.Strack has proposed that arrangement of artificial teeth in the same place as that of the natural dentition is the best way to maintain the stability of denture.In recent years, techniques of making dentures have been improved with the advancement of dental materials. I devised a method of simultaneously making impressions of upper and lower jaws using a injection device and a silicon impression material. I have routinely used this new system to make full dentures for clinical cases.On this occasion, registration of interocclusal relation, gothic arch tracing, simultaneoustaking of upper and lower impressions, and face bow transfer will be performed in front of you using patients, from the initial examination to the setting of full dentures.

Signs and symptoms of mandibular dysfunction in patients with suspected oral galvanism.

Fifty-four consecutive patients were examined by means of a self-administered questionnaire with questions related to general health and subjective symptoms. In addition, a clinical stomatognathic evaluation was carried out including palpation of the temporomandibular joints (TMJ) and the masticatory muscles and functional analysis of occlusion and mandibular mobility. High frequencies of general diseases were reported. The dominant subjective symptom was headache (62%), which often appeared daily. Symptoms such as pain from the teeth, pain in the face/jaws, and burning sensations in the tongue or oral cavity all appeared in more than half of the sample. The patients were frequently aware of parafunctions such as clenching of the teeth and tongue press. None of the investigated persons were completely free of clinical signs of dysfunction. The most frequent clinical finding was palpation tenderness in the masticatory muscles (96%), generally located in the masseter, temporal, and lateral pterygoid muscles. In more than half of the material TMJ findings were recorded, and more than one-third had TMJ pain. In 35% mandibular mobility was reduced. Occlusal interferences on retrusion and on the mediotrusion side were frequent findings. Impaired general state of health and multiple signs and symptoms of mandibular dysfunction were thus frequent findings in these polysymptomatic patients. Three-fourths of the patients needed treatment for mandibular dysfunction, indicating that great consideration must be made for the functional status of the masticatory system in clinical evaluation of so-called 'oral galvanists'.

Suckling Reflex in the Cat

FOR experimental purposes, some new-born kittens had to be reared in the laboratory away from the mother. Difficulties were encountered in inducing the kittens to accept milk administered by means of a glass pipette, until a way of evoking the suckling response was found. It was observed that slight pressure from the pipette applied to the premaxillary part of the palate invariably produced the suckling response which was maintained so long as the kitten was disposed to accept food. The main feature of this response is a slight protrusion of the tongue with side-to-side concavity of the dorsum, which assumes the shape of a shoehorn. The nozzle of the pipette is firmly grasped between the tongue and the premaxillary palate. The upturned margins of the more posterior part of the tongue press against the palate. A closed channel is thus formed within the oral cavity. The protruded tip of the tongue works up and down the side of the pipette in a milking action. Suction is created by alternate depression and elevation of the floor of the oral cavity along with the mandible, while the margins of the tongue and the palate together maintain the closed channel.