ABSTRACT
INTRODUCTION: Oral hypofunction comprises seven aspects of oral condition, including oral hygiene, oral dryness, bite strength, tongue-lip motor function, tongue pressure, masticatory function, and swallowing function. Each of these seven has a single diagnostic criterion; however, the use of a single indicator without consideration of sex, age, or other factors is controversial. The purpose of this study was to evaluate the association between the oral hypofunction test and sex, age, and number of remaining teeth. METHODS: The study was conducted at 12 facilities by the members of the Japanese Society of Geriatric Dentistry during April to December 2019. The participants comprised 181 healthy older adults aged 65 years and over (56.9% female; age range 65-95 years) who regularly visited these facilities. All tests of oral function and oral status available in Japan were performed on the participants, and the association between these tests and sex, age, and number of remaining teeth was examined. RESULTS: Sex differences were observed in masticatory function, bite force, lip closure force, jaw-opening force, oral diadochokinesis "ka," and tongue coating index (p < .05). In men, age was weakly (r = 0.20-0.40) associated with masticatory function, jaw-opening force, maximum tongue pressure, oral diadochokinesis, and swallowing function. In women, the number of remaining teeth, masticatory function, jaw-opening force, and oral diadochokinesis "ta" and "ka" was also weakly associated with age. CONCLUSIONS: Performance on the oral hypofunction test differs by sex, age, and number of remaining teeth. This means that the current single criterion for evaluation requires caution in its interpretation.
ABSTRACT
The present study investigated the cyclic fatigue properties of titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb) as implant materials and compared their properties with those of commercially pure titanium. Ti-6Al-4V and Ti-6Al-7Nb cylinders with diameters of 3.0 mm were examined. The surfaces of the cylinders were roughened by sand blasting with alumina particles and acid etching. Static and cyclic tests were performed according to ISO 14801:2016. The yield force in the static test (YS) was measured in 5 specimens of each alloy using a universal testing machine. The yield force in a cyclic test (YC) was measured in 20 specimens of each alloy using the staircase method, which involved applying a cyclic load at a frequency of 10 Hz for 106 cycles. After the cyclic loading tests, cross-sections of the specimens were examined under an optical microscope. The YS values for Ti-6Al-4V and Ti-6Al-7Nb were 1463 N±93 N and 1405 N±79 N, respectively, and the YC values were 870 N±58 N and 853 N±202 N, respectively. Microscopic observation revealed cracks on the tensile side of some of the specimens, including run outs and failures. The results of this study suggest that the YC values for Ti-6Al-4V and Ti-6Al-7Nb were 40% less than those for YS. The yield force of Grade-4 Cp-Ti significantly decreased after cyclic loading. The YC values for Ti-6Al-4V and Ti-6Al-7Nb were approximately 900 N, which was markedly greater than that for commercially pure, Grade-4 titanium (700 N).
Subject(s)
Alloys , Dental Implants , Titanium , Dental Materials , Microscopy, Electron, Scanning , Surface Properties , Materials Testing , Dental AlloysABSTRACT
AIM: This cross-sectional study had two aims: to assess the prevalence of oral frailty (OF), according to the Oral Frailty 5-Item Checklist (OF-5), among community-dwelling older adults; and to examine the associations among oral frailty, dietary variety, social engagement, and physical frailty. METHODS: We pooled data from two population-based studies (the Otassha Study and the Itabashi Longitudinal Study on Aging). With the OF-5, OF is characterized by the presence of two or more of the following: (i) fewer teeth, (ii) difficulty in chewing, (iii) difficulty in swallowing, (iv) dry mouth, and (v) low articulatory oral motor skills. We calculated the OF prevalence for each sex. We assessed dietary variety, social engagement, and physical frailty. Generalized structural equation modeling was employed to investigate the associations among oral frailty, low dietary variety (dietary variety score ≤3), social isolation (Lubben Social Network Scale score <12), and physical frailty (Japanese version of the Cardiovascular Health Study score ≥3). RESULTS: A total of 1206 individuals (626 women and 580 men) with a mean age of 74.7 years were included. The prevalence of OF was 36.7%, and it increased with age; however, there was no significant sex difference. OF was significantly indirectly associated with physical frailty via low dietary variety (odds ratio, 1.43; 95% confidence interval, 1.04-1.97) and social isolation (odds ratio, 1.42; 95% confidence interval, 1.04-1.94). CONCLUSIONS: Two of five community-dwelling older adults exhibited OF. Low dietary variety and social isolation are potential underlying mechanisms through which OF is indirectly associated with physical frailty. Geriatr Gerontol Int 2024; 24: 371-377.
Subject(s)
Frailty , Humans , Male , Female , Aged , Frailty/diagnosis , Frailty/epidemiology , Frail Elderly , Social Participation , Longitudinal Studies , Prevalence , Checklist , Cross-Sectional Studies , Independent Living , Geriatric Assessment/methodsABSTRACT
Background: Epididymal injuries without ipsilateral injuries of the testicles are rare. We report a case of a solitary right epididymal injury complicated by left testicular rupture. Case Presentation: A 21-year-old man experienced scrotal trauma caused by a motorcycle accident. Bilateral swelling and tenderness of the scrotum were observed. Ultrasonography and computed tomography revealed a ruptured left testicle; therefore, surgery was performed. During surgery, the left testicle was excised because it was completely ruptured, and the right testicle and epididymis were evaluated to identify the cause of swelling of the right scrotum. The right testis was not injured; however, the right epididymis was lacerated. Subsequently, the lacerated right epididymis was repaired using sutures. A semen analysis performed at 1, 4, and 7 months after surgery revealed the absence of sperm in the semen. Conclusion: Epididymal injuries should be considered as differential diagnoses for scrotal trauma.
ABSTRACT
AIM: To enable easy assessment of oral frailty; that is, an overlapping slight decline in multifaceted oral function, in any setting, we developed the oral frailty five-item checklist (OF-5), and examined its predictive validity for increased risks of physical frailty, physical disability and mortality among community-dwelling older adults. METHODS: This population-based cohort study randomly selected 2044 residents in Kashiwa, Japan, with no long-term care needs. Baseline data were collected in 2012, and follow-up data were collected in 2013, 2014, 2016, 2018 and 2021. The OF-5 includes five measures: fewer teeth, difficulty in chewing, difficulty in swallowing, dry mouth and low articulatory oral motor skills. Physical frailty was defined according to the Cardiovascular Health Study criteria. Physical disability and mortality determined from the long-term care insurance receipt database were followed for 9 years. RESULTS: Of 2031 eligible participants (mean age 73.1 ± 5.6 years; 51.1% women), 39.3% individuals with ≥2 OF-5 points had significantly increased prevalence and new-onset rate of physical frailty. After adjusting for potential confounders, oral frailty, defined as ≥2 OF-5 points, was associated with increased risks of physical disability (adjusted hazard ratio 1.40; 95% confidence interval 1.14-1.72) and mortality (adjusted hazard ratio 1.44; 95% confidence interval 1.11-1.87). The highest adjusted hazard ratios were observed in older adults with coexisting physical and oral frailty. CONCLUSIONS: The OF-5 showed strong predictive validity for physical frailty, physical disability and mortality in Japanese older adults. This assessment tool can be implemented in various settings and foster comprehensive prevention through interprofessional collaboration. Geriatr Gerontol Int 2023; 23: 651-659.
Subject(s)
Checklist , Frailty , Humans , Female , Aged , Male , Cohort Studies , Frailty/diagnosis , Frailty/epidemiology , Independent Living , Outcome Assessment, Health CareABSTRACT
The aim of this study was to investigate the effects of combining mechanical (ultrasonic) and chemical cleaning (using denture cleaners) on the surface roughness of silicone or acrylic soft relining materials. The silicone soft relining material with the lowest Shore A hardness and a acrylic soft relining material routinely used in Japan were selected. Four groups were established based on type of treatment: immersion in water (W); ultrasonic cleaning in tap water (U); ultrasonic cleaning in a hypochlorous acid denture cleanser (HU); or ultrasonic cleaning in an acidic denture cleanser (AU). Following the tests, surface roughness was determined as the arithmetic mean height of the surface (Sa) and maximum height (Sz). Data were analyzed using the Kruskal-Wallis test followed by Bonferroni correction for a multiple comparison. No significant difference was observed in the Sa or Sz of the silicone soft relining material between the 4 groups. Significant differences were observed in the Sa of the acrylic soft relining material between Groups W and HU (p=0.008) and between Groups W and AU (p=0.008), but no significant differences in the Sz among the 4 groups. Combining U with AU or U with HU yielded no increase in the surface roughness of the silicon soft relining material. The surface roughness of the acrylic soft relining material showed an increase, however, with the combination treatments used.
Subject(s)
Denture Liners , Silicones , Humans , Denture Cleansers , Materials Testing , Surface Properties , Water , Denture BasesABSTRACT
The aim of this randomized crossover trial was to clarify the effects of chewing gummy jelly containing a compound of decanoic acid, oligonol, methyl cellulose, and citral (DOMAC) on mental stress and autonomic nervous activity in facemask wearers. A placebo gummy jelly was used in conjunction with DOMAC. Eight healthy adults with no tooth loss (mean age: 35±5 yr) were included. The participants were required to chew one DOMAC or placebo gummy jelly for 5 min after wearing a facemask for 20 min in the laboratory, then the other gummy jelly after a washout period. Rate of change in salivary immunoglobulin A (IgA) as a marker of stress was compared between before and after chewing. Additionally, sympathetic and parasympathetic activity was compared at both time points. A significant difference was observed in the percentage change in salivary IgA from that at before wearing a facemask: 127±34% (mean±standard deviation) while wearing a facemask; 46±20% while chewing DOMAC gummies; and 47±26% while chewing placebo gummies (p<0.05). Parasympathetic nervous system activity was 971.2±1040.7 ms2 at 20 min after facemask wearing; 295.0±253.0 ms2 after DOMAC gummy chewing; and 1956.1±2798.0 ms2 after chewing a placebo gummy jelly; with significant differences only being found between 20 min after facemask wearing and after DOMAC gummy chewing (p<0.05). Sympathetic nervous system activity was 1.80±1.83 at 20 min after facemask wearing; 4.06±3.33 after DOMAC gummy chewing; and 4.95±7.02 after chewing a placebo gummy jelly; with significant differences only being found between 20 min after facemask wearing and after DOMAC gummy chewing. These results suggest that chewing gummy jellies containing DOMAC relieves stress caused by facemask wearing and activates sympathetic nervous system activity.
Subject(s)
Chewing Gum , Mastication , Adult , Humans , Mastication/physiology , Odorants , Cross-Over Studies , Autonomic Nervous System , Stress, Psychological/therapy , Immunoglobulin AABSTRACT
This study investigated decline in oral function in healthy young adults and compared it with that observed in an earlier studies employing older adults. The participants comprised 130 young healthy adults (mean age 24.1±2.9 yr), all with complete dentition. All participants underwent the oral hypofunction test established by the Japanese Society of Gerodontology, which evaluates oral hygiene, oral dryness, occlusal force, tongue-lip motor function (oral diadochokinetic rate; ODK), tongue pressure, and masticatory and swallowing function. The average value for and rate of hypofunction of each parameter were calculated. In healthy young adults, the scores were 28.9±17.1% for oral hygiene; 28.8±2.2 for oral dryness; 959.9±499.8 N for occlusal force; 7.0±0.8 times/sec for ODK /pa/, 7.6±0.8 times/sec for /ta/, and 6.9±0.9 times/sec for /ka/; 41.8±8.4 kPa for tongue pressure; 249.8±94.1 mg/dl for masticatory function; and 0.2±0.7 for swallowing function. No sign or symptom of change in oral function was observed at a high rate in young adults. Occlusal force, tongue-lip motor function, and tongue pressure showed a large difference in the rate of hypofunction between younger and older adults, however.
Subject(s)
Tongue , Xerostomia , Humans , Young Adult , Aged , Adult , Pressure , Mastication , Oral HygieneABSTRACT
This report describes the case of a 68-year-old man who visited our department complaining of poor denture retention and difficulty masticating due to damage to the retainer of a maxillary obturator. The patient had never been satisfied with the fit of this prosthesis, which had been placed two years earlier. The obturator and the mucosal surface of the denture base were incompatible, which had caused the retainer to detach. The maxillary defect was categorized as H3S0D0T0 according to the HS classification. The diagnosis was a masticatory disorder due to a damaged retainer and an incompatible denture base. Optical impressions and occlusal records were taken and a maxillary obturator fabricated using a CAD/CAM system. Dental CAD software was used to design and complete the tooth arrangement. The CAM system was used to mill a polyetherketoneketone disc based on the obtained data and composite resin used to face the teeth and gingiva. The maxillary obturator was placed after only three visits, spanning from impression taking to denture completion. The use of digital data allowed the time to denture completion to be shortened in addition to the number of hospital visits to be reduced. Compared to conventional impression taking, optical impressions also prevent discomfort, decreasing stress for the patient.
Subject(s)
Dental Implants , Maxillofacial Prosthesis , Male , Humans , Aged , Polymers , BenzophenonesABSTRACT
OBJECTIVES: Chewing increases frontal lobe activity, resulting in improved memory, learning ability, and response reaction time. This study aimed to assess the effects of elastic oral appliance chewing on the activities and functions of the frontal lobe. METHODS: The study participants were 15 healthy men with full dentulous (mean age, 27.4 ± 4.1 years). A prospective crossover design was used to assess frontal lobe activities and functions. Changes in frontal lobe activities were measured with near-infrared spectroscopy (NIRS). At baseline, the participants were assessed in the resting state. Changes in channels #7, representing right frontal lobe activities by NIRS, and #10, representing left frontal lobe activities, during the first and second chewing periods in a total of two periods were evaluated. Frontal lobe functions were measured using the Trail Making Test Part A (TMT-A) in the resting state and after elastic oral appliance or gum chewing. These values were compared with each period. RESULTS: Elastic oral appliance chewing caused significant differences between the baseline and first chewing periods for channel #7 (p = .032) and significant differences between the baseline and second chewing periods for channels #7 and #10 (p < .001 and p < .001, respectively) using NIRS. Moreover, significant differences were found in the TMT-A results between the resting state and elastic oral appliance chewing (p = .04). CONCLUSIONS: Elastic oral appliance chewing improves frontal lobe activities to a level similar to that obtained with gum chewing.
Subject(s)
Frontal Lobe , Mastication , Adult , Humans , Male , Young Adult , Chewing Gum , Learning , Mastication/physiology , Prospective Studies , Cross-Over StudiesABSTRACT
A neurofibroma not associated with neurofibromatosis type 1 is termed solitary neurofibroma. A solitary giant neurofibroma of the thigh is an extremely rare tumor. A 44-year-old woman presented to us with a well-defined swelling on her left thigh for 10 years. On the basis of magnetic resonance image finding, we diagnosed the tumor as a neurofibroma. We excised the tumor and the pathological findings established the diagnosis of neurofibroma. There was no recurrence 8-months after surgery.
ABSTRACT
INTRODUCTION: Malnutrition and risk of malnutrition continues to be a common finding in elders, yet its association with oral function in hospitalised patients remains unclear. MATERIAL AND METHODS: Patients aged 70 years or over who had been hospitalised for non-acute rehabilitation were recruited. Nutritional risk was screened using the Mini-Nutritional Assessment Short Form (MNA-SF) and Nutritional Risk Screening (NRS) scores. Malnutrition was assessed according to the Global Leadership Initiative on Malnutrition (GLIM) criteria. All participants underwent the oral hypofunction test battery, evaluating oral hygiene, oral dryness, occlusal force, tongue-lip motor function, tongue pressure, masticatory and swallowing function. Statistical analyses comprised Mann-Whitney or Kruskal-Wallis tests. Bivariate associations between categorical variables were tested using the Pearson chi-square test; for continuous variables, the Spearman correlation was calculated. A P-value < .05 was considered statistically significant. RESULTS: Sixty patients aged a mean 82.5 ± 7.0 years participated. Some 88.3% were diagnosed with oral hypofunction, and this was more common in older patients (P = .020). Analysing the 7 oral hypofunction tests as an interval variable (NiOF) revealed additional correlations with number of teeth (ρ = 0.477) as well as the nutritional risk, evaluated by the MNA-SF (ρ = -0.284) and NRS (ρ = 0.317) scores. NiOF scores were higher among denture wearers (P = .003). GLIM did not confirm the correlation with NiOF. Biomarkers such as serum albumin and CRP were not associated with the NiOF score. CONCLUSION: In this sample, the association between oral function and nutritional state is more obvious in nutritional risk scores than in the malnutrition diagnosis by GLIM.
Subject(s)
Malnutrition , Nutritional Status , Aged , Aged, 80 and over , Geriatric Assessment , Humans , Malnutrition/diagnosis , Nutrition Assessment , Pressure , TongueABSTRACT
OBJECTIVES: Undernutrition is associated with frailty, one of the common reasons for seeking long-term care. In older adults, nutritional status is known to be associated with oral function; however, it is not yet known if there is a similar association in middle-aged adults. The present study determined the association between nutritional status and oral function in middle-aged adults. MATERIAL AND METHODS: This cross-sectional study was conducted in 117 outpatients aged 40-64 years who underwent dental check-up at a private dental clinic. Factors associated with oral function, including oral moisture, number of teeth present, oral diadochokinesis, tongue pressure, lip-seal strength, and masticatory performance, were evaluated. Body mass index (BMI), fat-free mass index (FFMI), and skeletal muscle mass index (SMI) were analyzed as nutritional statuses. Pearson's correlation analysis was conducted to determine the correlation between nutritional statuses and other variables. Multiple linear regression analysis was performed, with adjustment for age and sex, using BMI, FFMI, or SMI as response variables and oral moisture, maximum tongue pressure, lip-seal strength, oral diadochokinetic rate, and masticatory performance as explanatory variables. RESULTS: All nutritional statuses showed significant correlation with maximum tongue pressure and lip-seal strength. Multiple linear regression analysis revealed that BMI was associated with maximum tongue pressure and lip-seal strength, whereas FFMI and SMI showed significant association with sex, maximum tongue pressure, and lip-seal strength. CONCLUSIONS: In middle-aged outpatients at a regional dental clinic, lip-seal strength and tongue pressure were positively associated with BMI, FFMI, and SMI.
Subject(s)
Muscles , Tongue , Aged , Cross-Sectional Studies , Humans , Middle Aged , Pressure , Tongue/physiologyABSTRACT
Background: The aim was to clarify the range of mouth opening required to minimize the development of oral mucositis on the palate while using a positioning stent during radiotherapy in patients with tongue cancer. A positioning stent is used to reduce the severity of oral mucositis; however, requirements for fabricating the device have not been standardized. In particular, the range of mouth opening required while using a stent to prevent radiation-induced oral mucositis has not been determined. Materials and methods: We retrospectively analyzed medical records and computed tomography (CT) images of nine patients who had undergone radiotherapy for tongue cancer. Irradiation dose for the palate and range of mouth opening while using the positioning stent was calculated from CT images and the radiotherapy treatment planning program. Results: The irradiation dose presented as medians and interquartile range (IQR) for the palate was 1.6 (IQR: 1.1-2.2) Gy with the use of the positioning stent and 37.2 (IQR: 17.5-44.1) Gy without the use of the positioning stent. The range of mouth opening was 19-37 [mean ± standard deviation (SD): 26 ± 5.6] mm, and it correlated with the attenuation amount of irradiation dose to the palate (r = 0.673, p = 0.0467). Regression equation was y = 0.21x + 19. Conclusions: Our study may be useful for deriving the relationship between the attenuation amount of irradiation of the palate with the positioning stent and the amount of mouth opening required for this attenuation.
ABSTRACT
OBJECTIVE: To measure the occlusal force in the same group of patients with the Dental Prescale 50H type R and the Dental Prescale II, examine the association between them, and determine the reference value for Dental Prescale II that corresponds to the 50H type R 200 N reference value used to make a diagnosis of oral hypofunction. BACKGROUND: Reduced occlusal force, a measure of frailty in older persons, was previously determined with Prescale 50H type R pressure-sensitive film, but it has been replaced by the Prescale II. MATERIALS AND METHODS: The study participants were 441 men and women aged ≥ 65 (mean, 71.8 ± 5.3) years. The occlusal force was measured with the two different types of pressure-sensitive film, and their association was examined. Receiver operating characteristic curves for the Prescale II measured values were created with the 200 N reference value used for the 50H type R film as the cut-off value. RESULTS: The analysis set included 391 participants for whom measurements were obtained using both the 50H type R and the Prescale II. Linear regression analysis produced regression equations, and a ROC curve analysis provided reference values of 500 N for the Prescale II (without pressure filter) and 350 N for the Prescale II (with pressure filter). CONCLUSION: In occlusal force tests for making a diagnosis of oral hypofunction, reference values for the Prescale II (without pressure filter) and for the Prescale II (with pressure filter) were determined. The findings suggested that the Prescale II can be used as a diagnostic examination for oral hypofunction.
Subject(s)
Bite Force , Frailty , Aged , Aged, 80 and over , Female , Humans , Male , ROC CurveABSTRACT
Lip-seal strength is important for articulating bilabials, capturing food during eating, maintaining fluid within the oral cavity before swallowing, and achieving swallowing pressure. The objective of this study was to investigate the effect of lip-seal resistance training on lip-seal strength in young adults. The participants comprised 15 young healthy adults aged 26-34 years, all with complete dentition. Each was required to perform lip-seal resistance training 5 weekdays a week for 4 weeks with a commercially available instrument for that purpose. The instrument was placed on the midline, left corner, and right corner of the mouth, and pulled forward, leftward, and rightward, respectively. The participants were required to pull the training instrument forcefully while resisting by closing the lips together as strongly as possible until the instrument exited the lips. Lip-seal strength was measured at before and after training using a measurement device. Change in lip-seal strength between before and after training was analyzed using the Wilcoxon signed rank test. The mean lip-seal strength was 8.9±1.5 N before training and 10.4±1.8 N after. A significant difference was observed in lip-seal strength between before and after training (p=0.003), and the mean increase during the training period was 18.1±17.6%. The results showed that lip-seal resistance training for 4 weeks increased lip-seal strength in young adults. These findings suggest that training that involves pulling not only in a forward direction, but also in bilateral directions strongly stimulates the orbicularis oris muscle, resulting in an increase in lip-seal strength.
Subject(s)
Lip , Resistance Training , Deglutition , Facial Muscles , Food , Humans , Young AdultABSTRACT
Oral hypofunction, resulting from a combined decrease in multiple oral functions, may affect systemic-condition deterioration; however, few studies have examined the association between oral hypofunction and general health among older adults. In this cross-sectional study, we examined the relationship between oral hypofunction and sarcopenia in community-dwelling older adults. We included 878 adults (268 men and 610 women, mean age 76.5 ± 8.3 years). Tongue coating index, oral moisture, occlusal force, oral diadochokinesis (/pa/,/ta/,/ka/), tongue pressure, mas-ticatory function, and swallowing function were evaluated as indicators of oral hypofunction. Grip strength, gait speed, and skeletal muscle mass index were measured as diagnostic sarcopenia parameters. The association between oral hypofunction and sarcopenia was examined via logistic regression using sarcopenia as the dependent variable. Oral hypofunction prevalence was 50.5% overall, 40.3% in men, and 54.9% in women. The prevalence of sarcopenia was 18.6% overall, 9.7% in men, and 22.5% in women. A logistic regression showed oral hypofunction, age, body mass index, higher-level functional capacity, and serum albumin level were significantly associated with sarcopenia. Sarcopenia occurred at an increased frequency in patients diagnosed with oral hypofunction (odds ratio: 1.59, 95% confidence interval: 1.02-2.47); accordingly, oral hypofunction appears to be significantly associated with sarcopenia.
Subject(s)
Sarcopenia , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Hand Strength , Humans , Independent Living , Male , Muscle Strength , Muscle, Skeletal , Pressure , Sarcopenia/epidemiology , TongueABSTRACT
OBJECTIVES: Lip-seal strength, which represents the muscle strength of the lips, appears to chiefly contribute to mastication and pronunciation. However, the functional characteristics of lip-seal strength in adults are still undefined. The present study aimed to understand not only the distribution of lip-seal strength in adult men and women but also the effect of age on this strength and identify oral motor functions correlated with lip-seal strength. MATERIALS AND METHODS: The subjects included 339 participants (men: 170, age 39.2 ± 18.2 years; women: 169, age 43.1 ± 19.7 years). Oral motor function was evaluated for lip-seal strength, oral diadochokinesis (ODK), tongue pressure, occlusal force, and masticatory performance. Statistical analyses included the Shapiro-Wilk, Mann-Whitney U, and Jonckheere-Terpstra tests, in addition to the Spearman's correlation analysis and curvilinear regression analysis. RESULTS: Lip-seal strength did not have a normal distribution (p < 0.001). The mean ± standard deviation and median (first quartile, third quartile) of lip-seal strength were 11.2 ± 3.4 and 10.9 (8.7, 13.2)N for the whole sample, 12.3 ± 3.4 and 11.9 (9.4, 14.4)N for men, and 10.2 ± 3.0 and 9.9 (8.0, 12.0)N for women. A significant difference was observed in lip-seal strength between men and women (p < 0.001). Oral motor functions showed a marked correlation with lip-seal strength, including tongue pressure, occlusal force, and masticatory performance and ODK (/pa/ and /ta/), tongue pressure, and masticatory ability in men and women, respectively. In women, lip-seal strength declined with increase in age. CONCLUSIONS: Lip-seal strength was non-normally distributed in both men and women, and lip-seal strength was affected by age only in women. Lip-seal strength and multiple oral motor functions were significantly correlated. Because the indicators of perioral muscle strength and performance were correlated with lip-seal strength, lip-seal strength may also partially reflect the condition of the perioral muscles.