Differences in Orofacial Muscle Strength According to Age and Sex in East Asian Healthy Adults

The neurorehabilitation of post-stroke dysphagia: Physiology and pathophysiology

Swallowing is a complex process involving the precise contractions of numerous muscles of the head and neck, which act to process and shepherd ingested material from the oral cavity to its eventual destination, the stomach. Over the past five decades, information from animal and human studies has laid bare the complex network of neurones in the brainstem, cortex and cerebellum that are responsible for orchestrating each normal swallow. Amidst this complexity, problems can and often do occur that result in dysphagia, defined as impaired or disordered swallowing. Dysphagia is common, arising from multiple varied disease processes that can affect any of the neuromuscular structures involved in swallowing. Post-stroke dysphagia (PSD) remains the most prevalent and most commonly studied form of dysphagia and, as such, provides an important disease model to assess dysphagia physiology and pathophysiology. In this review, we explore the complex neuroanatomical processes that occur during normal swallowing and PSD. This includes how strokes cause dysphagia, the mechanisms through which natural neuroplastic recovery occurs, current treatments for patients with persistent dysphagia and emerging neuromodulatory treatments.

Clinical signs to predict the severity of dysphagia in Acute Ischemic Stroke patients

OBJECTIVES

In the current era, clinicians working in areas with limited and/or without facilities are only able to manage their patients based on clinical signs to detect dysphagia. This study assesses the performance of 5 simple clinical signs for predicting the severity of dysphagia.

METHODS

We systematically documented 5 targeted bedside clinical signs within 24 h after admission in 737 consecutive patients with acute stroke. We examined the median onset of each sign and calculated their ratios associated with severe dysphagia. The performance and significance of these special clinical signs were evaluated by further computation.

RESULTS

In total, 184 of 737 AIS patients were screened positive dysphagia by the modified V-VST. The 5 targeted bedside clinical signs were differed among the patients with and without dysphagia. Patients with serious dysphagia (n = 61,33.15%) showed higher positive percentages of larynx movement disorders than those classified as moderate (73.77% [60.99%-83.50%] vs 29.27% [21.82%-38.03%], p < 0.001). Logistic regression analyses conducted in the subsets confirmed larynx movement disorders as an independent predictor of dysphagia severity.

CONCLUSIONS

Larynx movement disorders is correlated with a higher probability of severe dysphagia as measured by the modified V-VST in AIS patients.

Age- and sex-related differences in 3D facial shape and muscle pressure in subjects with normal occlusion

BACKGROUND AND OBJECTIVE(S): (1) To derive descriptive statistics of three-dimensional (3D) facial shape, lip and cheek muscle pressure in subjects of European descent with normal dental occlusion. (2) To analyse the effect of age and sex on 3D-facial soft tissue morphology and muscle pressure in the same sample. (3) To assess the independent effect of muscle pressure on face shape.

METHOD

129 subjects with normal occlusion were cross-sectionally recruited and divided into: children (mixed dentition), adolescents and adults (permanent dentition, < and ≥18 years respectively). Muscle pressure was recorded using the Iowa Oral Performance Instrument. MeshLab, MeVisLab and Meshmonk tool box were used to clean, annotate landmarks and generate the 3D images. Two-way analysis of variance and post-hoc tests were used to analyse age and sex differences in face shape and muscle pressure. The effect of muscle pressure on face shape was analysed by Pearson correlation and Partial Least Square regression.

RESULTS

Significant facial differences were observed between adults and adolescents and adults and children in both sexes, showing flattening of cheeks and lips and protrusion of nose and chin. Significant cheek protrusion and retrusion of the vertical midface were found in adult women compared to men. Lip and cheek pressure increased with age, but their effect on face shape was not significant.

CONCLUSIONS

This study provides 3D age- and sex-specific facial models and muscle pressure of subjects without malocclusion. These can be used as a reference for clinicians focused on facial assessment in treatment planning and follow-up.

Comparison of oral physiological and salivary rheological properties of Chinese Mongolian and Han young adults

OBJECTIVES

Consumers' oral physiology and salivary properties are greatly dependent on dietary backgrounds, and this in turn may impact food perception and preferences. Scarce studies are available on the oral physiology and salivary rheology of Chinese participants with different dietary and ethnic backgrounds.

DESIGN

This study examined two ethnic groups, Chinese Han and Chinese Mongolian healthy young adults, and explored the differences in oral physiology and salivary rheological properties. Official data suggested that Chinese Mongolians tend to consume more red meat and dairy, and Chinese Han tend to consume more carbohydrates. 200 Han and 104 Mongolian participants were evaluated for the oral physiological and salivary rheological parameters (maximum bite force of incisor and molar teeth, maximum tongue pressure and maximum oral volume; the surface tension, shear viscosity and extensional viscosity of unstimulated and stimulated whole saliva samples).

RESULTS

Distinct differences between two ethnic groups were found, particularly in their bite forces and salivary physical properties. Chinese Mongolian participants had significantly higher incisor bite force (168 N) than Chinese Han (146 N). In addition, Chinese Han had significantly lower unstimulated whole saliva flow rate than Chinese Mongolians; and significantly higher salivary surface tension, shear viscosity and extensional viscosity, in both unstimulated and stimulated whole saliva samples.

CONCLUSIONS

Chinese Han and Chinese Mongolian participants exhibited different oral physiological and salivary rheological properties; and considering the dietary differences between the two ethnicities, the findings from this study suggest possible associations between dietary habits and oral physiological & saliva rheological properties.

Variability in tongue pressure among elderly and young healthy cohorts: A systematic review and meta-analysis

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.

Factors associated with signs of aspiration in older adults: A prospective study

This was a prospective cohort design study that followed a group of older adults for up to 12 months. Two hundred and ninety-one participants with a mean age of 81.4 ± 9.1 years were recruited. Signs of aspiration were screened by the Yale Swallow Protocol. Variables investigated for risk were oromotor functions, self-perception of swallowing function, cognitive function, and medical history. Seventy participants were revisited for a follow-up aspiration screening 8 to 9 months later. Multivariate logistic regression found that male sex, need for assistance for feeding and mobility, reduced cognitive function, subjective judgement of swallowing function, and oromotor function were major variables that can be used to screen for older adults who may require referrals for swallowing assessment. Those who continue to show signs of aspiration across time exhibit a more frail profile than their counterparts who do not.

Effects of Age, Sex, Disease, and Exercise Training on Lip Muscle Strength

Lip muscle strength has been shown to influence daily functional activities such as facial expression, speech production, and eating. In this review, recent literature regarding lip strength and exercise training responses are summarized, highlighting the influence of sex, age, and disease (e.g., stroke). A search using five electronic databases was conducted. Twelve studies were identified from the search, which included five studies using healthy adults and seven studies using patients with diseases or chronic ailments. Regardless of the population, lip strength training multiple times a day for a relatively short term (<24 weeks) has resulted in improvements of lip muscle strength. This change in lip strength has been observed in both young and old participants. Although changes in strength have been observed in both men and women, we are unaware of any studies that have tested whether there are sex differences in this response. The same directional change can be expected for patients with stroke and patients with lip incompetence, but the magnitude of the training effect seems to be higher in healthy people.

A Practical Method for Assessing Lip Compression Strengthening in Healthy Adults

There is no practical and accessible assessment method to evaluate lip muscle compression strength. The purpose of this study was to examine the relationship between the standard method (i.e., Iowa Oral Performance Instrument) and a practical method in healthy adults. In order to achieve our research purpose, ninety-eight healthy adults (18–40 years) completed lip compression strength measurements (standard method) and lip grasping performance tests using a standard recyclable plastic water bottle (practical method). In the overall sample, the mean and standard deviation for standard method and practical method was 26.7 (7.0) kPa and 255 (119) g, respectively. For the overall sample (n = 98), there was a positive relationship between the two strength tasks [r = 0.56 (0.41, 0.68)]. When separated by sex, positive correlations were observed for men and women with no differences between the observed correlations [difference of 0.06 (−0.2646, 0.3917)]. This result indicates that those individuals who are strong in the standard task will often be strong in the practical task. Future research is needed to determine how well changes in each test track with each other in response to a lip strength training program.

Tongue strengthening exercise is effective in improving the oropharyngeal muscles associated with swallowing in community-dwelling older adults in South Korea: A randomized trial

BACKGROUND

Tongue strengthening exercise (TSE) is a remedial method for the training of swallowing-related muscles in the oropharyngeal phase. However, clinical evidence of its effectiveness is insufficient.

METHODS

To investigate the effect of TSE on the oropharyngeal muscles associated with swallowing in older adults, in this study, 40 elder adults living in the community were recruited and assigned to 2 groups. The experimental group performed a TSE with a 1-repetition maximum resistance level of 70%. The exercise was divided into an isometric and isotonic part. The control group did not perform an exercise. We measured the muscle strength and thickness of the tongue and suprahyoid muscles using an Iowa Oral Performance Instrument and ultrasonography.

RESULTS

The experimental group showed a statistically significant increase in tongue muscle strength and thickness in the oral phase (P = .001 and <.001, respectively). In the pharyngeal phase, the experimental group showed a statistically significant increase in the mylohyoid and digastric muscles (suprahyoid muscles) (P = .045 and .019, respectively). The control group showed no statistically significant changes.

CONCLUSION

TSE is effective in increasing the strength and thickness of the oropharyngeal muscles of elder adults and is recommended for those who are vulnerable to swallowing difficulties.

Comparison of orbicularis oris muscle strength and endurance in young and elderly adults

[Purpose] The purpose of this study was to compare the strength and endurance of the orbicularis oris muscle in healthy Korean (young vs. elderly adults). [Participants and Methods] A total of 60 participants (30 young adults and 30 elderly adults) were recruited. The Iowa Oral Performance Instrument was used to measure orbicularis oris muscle maximal strength and endurance. [Results] Elderly adults showed significantly lower orbicularis oris muscle strength and endurance than younger adults. [Conclusion] This study confirmed a significant age-related decrease in orbicularis oris muscle strength and endurance. The data collected will be useful as a basis for future on speech and swallowing therapy.

Tongue pressure distribution of individual normal occlusions and exploration of related factors

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.

Oropharyngeal swallowing function in patients with presbyphagia

[Purpose] This study investigated the characteristics of oropharyngeal swallowing function in patients with presbyphagia. [Participants and Methods] Data for 25 patients with presbyphagia were retrospectively analyzed. The oropharyngeal swallowing function was evaluated using VDS based on videofluoroscopic swallowing study. [Results] Lip closure, mastication, laryngeal elevation, and aspiration showed a relative decrease in function. [Conclusion] This study showed a reduction in oropharyngeal swallowing in patients with presbyphagia. Our results may help in the diagnosis and treatment of presbyphagia.

Effect of orbicularis oris muscle training on muscle strength and lip closure function in patients with stroke and swallowing disorder

[Purpose] We aimed to investigate the effect of resistance training of the orbicularis oris muscles on lip muscle strength and closure function in patients with swallowing disorder with facial palsy after stroke. [Participants and Methods] This study recruited 10 patients with swallowing disorder and facial palsy after stroke. All the participants received orbicularis oris muscle training at an intensity of 70% of 1 repetition maximum by using an Iowa oral performance instrument. Muscle strength and lip closure function were evaluated after orbicularis oris muscle training. [Results] After the intervention, the orbicularis oris muscle strength showed a statistically significant increase from 20.5 ± 5.15 to 25.3 ± 4.2 kilopascal. Lip closure function showed a statistically significant improvement from 2.6 ± 1.5 to 1.2 ± 1.0. [Conclusion] This study recommends to train at an intensity of 70% of 1 repetition maximum for 4 weeks to increase theorbicularis oris muscle strength and improve lip closure function.

Decline in tongue pressure during perioperative period in cancer patients without oral feeding

BACKGROUND AND AIMS

Systemic muscle wasting during perioperative periods has a major impact on postoperative morbidity. However, data on oropharyngeal muscle weakness after surgery are scarce. We examined whether maximum tongue pressure (MTP) and hand grip strength (HGS) diminished during the perioperative period without and with oral feeding in patients receiving cancer surgery.

METHODS

A total of 258 patients undergoing cancer surgery who had visited a hospital dental clinic were prospectively recruited between October 2015 and February 2016. MTP and HGS were measured on the day before and 4 days after surgery. Data on age, sex, tumor location, surgical procedure, and oral feeding status were obtained from patient medical records. We analyzed for differences in the perioperative changes of MTP and HGS according to surgical procedure, oral feeding, and tumor location using ANOVA.

RESULTS

Neither MTP nor HGS differed significantly among tumor locations before surgery. The proportion of patients with an oral diet at 4 days after surgery was 36.7% and 34.5% for upper GI and colorectum groups versus 89.2% and 86.4% for genitourinary and lung groups, respectively. During the perioperative period, MTP decreased more significantly in patients without oral feeding than in those with oral feeding at 4 days after surgery (P < 0.01). HGS was not affected by postoperative oral feeding status. Both MTP and HGS decreased more significantly in the upper gastrointestinal group than in the genitourinary and lung groups (P < 0.05), except for MTP between upper GI and genitourinary groups (P = 0.10).

CONCLUSIONS

MTP, but not HGS, diminishes significantly during the perioperative period without oral feeding. As tongue muscle disuse after surgery may adversely impact postoperative oropharyngeal muscle decline, perioperative tongue muscle strengthening exercises may assist in maintaining muscle strength and good oral feeding.

A Self-Reported Association between Temporomandibular Joint Disorders, Headaches, and Stress

AIMS AND OBJECTIVES

Temporomandibular joint disorder (TMD) is an umbrella term for a number of conditions in the area of the joint, temple, and masticatory system. Many of those with TMD also suffer from headaches and anxiety. The aims and objectives of this study were to determine if there exists an association between the Diagnostic Criteria of TMD (DC/TMD) symptom questionnaire and report of headaches as well as stress.

MATERIALS AND METHODS

A cross-sectional study was implemented via the use of the DC/TMD symptom questionnaire and the perceived stress scale (PSS). This was distributed conveniently among dental students in a multi-dental school setting in Riyadh, Saudi Arabia, and was completed by 152 dental students. Odds ratios, Chi-square, and their corresponding 95% confidence intervals are reported. Statistical significance was set at P ≤ 0.05.

RESULTS

Those who ticked yes for pain on the TMD pain screener for pain with chewing hard or tough food, pain on mouth opening and lateral excursion, and pain with jaw habits as parafunction were at an odds risk from twice to thrice as likely to experience headaches. Similarly, those with poor coping skills on the PSS were more likely to have headaches (P = 0.002). Likewise, positive answers on the screener and symptom questionnaire were relevant with higher stress scores on the PSS.

CONCLUSION

This study clarifies and reiterates the intertwined power of both stress and headaches; the former being a role player in TMD progression and the latter its product. TMD is unfortunately on the rise; it should not be brushed off as a nuisance. A multidisciplinary approach in diagnosis and treatment of both TMD and headaches by a team of orofacial pain specialist, neurologist, psychiatrist and/or psychologist, and physical therapists to untangle the deceiving presentation of both conditions would not only provide a more favorable prognosis but also improve cost and time expenditures.

Effect of neuromuscular electrical stimulation on lip strength and closure function in patients with dysphagia after stroke

[Purpose] This study aimed to investigate the effect of neuromuscular electrical stimulation (NMES) on lip strength and closure function of patients with dysphagia after stroke. [Subjects and Methods] Eight patients with dysphagia were recruited. NMES was applied to the orbicularis oris muscle. All the participants received NMES for 30 min/d, 5 d/wk, for 4 weeks. Lip strength was measured using the Iowa Oral Performance Instrument. To assess lip closure, the lip closure subitem of the videofluoroscopic dysphagia scale was used. [Results] Lip strength showed significant improvement and lip closure function showed a significant decrease. [Conclusion] This study demonstrates that NMES is useful for improving lip strength and closure function.

Effects of electrical stimulation combined with dysphagia therapy in elderly individual with oropharyngeal dysphagia: a case study

[Purpose] The purpose of the present study was to investigate the effects of dysphagia therapy in an old man with difficulty swallowing in the oral and pharyngeal phases. [Subjects and Methods] The subject was a 72-year-old man with no history of neurological disorders. He was admitted to local hospital because of the complaint of swallowing difficulty. The interventions performed were electrical stimulation and conventional dysphagia therapy. We assessed the tongue and lip muscle strengths. Swallowing function was evaluated by using the videofluoroscopic dysphagia and penetration-aspiration scales. [Results] After the intervention, the tongue and lip muscle strengths increased from 35 to 39 kPa and from 18 to 23 kPa, respectively. Moreover, the oral and pharyngeal phases of the videofluoroscopic dysphagia scale were improved. Furthermore, aspiration decreased from 4 to 2 points in the penetration-aspiration scale. [Conclusion] Our results suggest that electrical stimulation and conventional dysphagia therapy were effective in improving the swallowing function in an elderly individual with dysphagia.

Effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy

[Purpose] The aim of this study was to investigate the effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy. [Subjects and Methods] Nine subjects received the electrical stimulation and traditional dysphagia therapy. Electrical stimulation was applied to stimulate each subject’s facial muscles 30 minutes a day, 5 days a week, for 4 weeks. [Results] Subjects showed significant improvement in cheek and lip strength and oral function after the intervention. [Conclusion] This study demonstrates that electrical stimulation improves facial muscle strength and oral function in stroke patients with dysphagia.

The Relationship Between Tongue Pressure and Oral Dysphagia in Stroke Patients

Objective

To evaluate the relationships between tongue pressure and different aspects of the oral-phase swallowing function.

Methods

We included 96 stroke patients with dysphagia, ranging in age from 40 to 88 years (mean, 63.7 years). Measurements of tongue pressure were obtained with the Iowa Oral Performance Instrument, a device with established normative data. Three trials of maximum performance were performed for lip closure pressure (LP), anterior hard palate-to-tongue pressure (AP), and posterior hard palate-to-tongue pressure (PP); buccal-to-tongue pressures on both sides were also recorded (buccal-to-tongue pressure, on the weak side [BW]; buccal-to-tongue pressure, on the healthy side [BH]). The average pressure in each result was compared between the groups. Clinical evaluation of the swallowing function was performed with a videofluoroscopic swallowing study.

Results

The average maximum AP and PP values in the intact LC group were significantly higher than those in the inadequate lip closure group (AP, p=0.003; PP, p<0.001). AP and PP showed significant relationships with bolus formation (BF), mastication, premature bolus loss (PBL), tongue to palate contact (TP), and oral transit time (OTT). Furthermore, LP, BW, and BH values were significantly higher in the groups with intact mastication, without PBL and intact TP.

Conclusion

These findings indicate that the tongue pressure appears to be closely related to the oral-phase swallowing function in post-stroke patients, especially BF, mastication, PBL, TP and OTT.