Development of the Food Acceptance Questionnaire for Thai Partial and Complete Edentulism.

This study aimed to develop the Food Acceptance Questionnaire (FAQ) to assess the masticatory ability of Thai older adults (≥60 years). Fifty participants were interviewed using open-ended questions about food they regularly consumed and avoided due to difficulty chewing. From a list of 140 items, 100 were recruited for a trial version of the FAQ. A total of 154 participants responded to the 5-point Likert scale on their chewing perception of each food item (1, impossible to chew; 5, most easily eaten). The average response of each food item was used as the chewing index (CI). The 100 food items were ranked and divided into five grades based on their CIs. Masticatory performance (MP) was objectively assessed by a visual scoring method using gummy jelly (UHA Mikakuto). Two foods from each grade that demonstrated the highest correlation with MP were selected to form the final 10-item FAQ. The FAQ score was calculated by summarizing the responses of 10 items. MP correlated strongly with the FAQ score (r = 0.57, p < 0.001), indicating its predictive validity. Furthermore, the FAQ indicates strong internal consistency (Cronbach's alpha coefficient = 0.90), indicating high reliability. In conclusion, this newly developed 10-item FAQ is valid and reliable for assessing the masticatory ability of Thai older adults.

TAS2R38 polymorphisms and oral diseases in Thais: a cross-sectional study.

BACKGROUND: Polymorphisms at positions 49, 262, and 296 in the TAS2R38 bitter taste receptor gene result in two common genetic haplotypes, PAV and AVI, named for the resulting amino acid substitutions. TAS2R38 genotype has been previously associated with caries risk in children. This study aimed to identify TAS2R38 polymorphisms among Thais and to explore any association between genotype and oral diseases. METHODS: Patients seeking care at Khon Kaen University Dental Hospital in Thailand were recruited to participate in the study. Saliva was collected for DNA extraction and genotyping. Patients completed a questionnaire to collect demographic variables and assess oral self-care behaviors. A calibrated dentist conducted an examination that included periodontal charting and recording of decayed, missing, and filled teeth (DMFT). RESULTS: A total of 250 patients (19-75 years) were enrolled in the study (116 males). Two haplotypes, PAV (67.2%) and AVI (32.8%) were found, resulting in 3 diplotypes; PAV/PAV (46.0%), PAV/AVI (42.4%) and AVI/AVI (11.6%). DMFT and periodontal status of 238 participants were recorded. The three diplotype groups were similar in age, sex, socio-economic indicators, oral self-care, and number of teeth. The odds of having periodontal disease, defined as at least one site with probing depth ≥ 5 mm, were lower in AVI/AVI and PAV/AVI compared with PAV/PAV. PAV/AVI tended to have less DMFT, while AVI/AVI tended to have more DMFT compared with PAV/PAV, however these trends did not reach statistical significance. CONCLUSIONS: The frequency distribution of TAS2R38 genotypes was similar to that reported for other Asian populations. AVI/AVI genotype was associated with decreased prevalence of periodontal disease among Thai dental patients, whereas there was no significant association between TAS2R38 genotype and prevalence of tooth decay in this patient population.

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.

Anthocyanin complex niosome gel accelerates oral wound healing: In vitro and clinical studies.

An anthocyanin complex (AC), composed of extracts of purple waxy corn and blue butterfly pea petals, and AC niosomes, bilayered vesicles of non-ionic surfactants, were compared in in vitro and clinical studies. Cultured fibroblasts subjected to a scratch wound were monitored for cell viability, cell migration, nuclear morphology and protein expression. Scratched cells showed accelerated wound healing activity, returning to normal 24 h after treatment with AC niosomes (0.002 mg/mL). Western blots and immunocytochemistry indicated upregulation of type I, III and IV collagens, fibronectin and laminins in AC niosome-treated scratched cells. A randomized block placebo-controlled double-blind clinical trial in 60 volunteers (18-60 years old) with oral wounds indicated that AC niosome gel accelerated wound closure, reduced pain due to the oral wounds and improved participants' quality of life more than AC gel, triamcinolone gel and placebo gel. These data are consistent with enhanced delivery of AC to fibroblasts by use of niosomes. AC niosomes activated fibroblasts within wounded regions and accelerated wound healing, indicating that AC niosomes have therapeutic potential.

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

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

Effect of biting speed and jaw separation on force used to incise food.

Biting food too quickly might affect the control of jaw-closing muscles and the estimation of bite force. The objectives of this study were to compare the incisal bite forces used to cut food and the activity of masseter (MA) and anterior temporalis (AT) muscles between slow, habitual and fast biting speeds and also between small and large jaw openings. Twenty subjects were asked to use their incisors to cut through a 5 mm thick of chewing gum. In the first experiment, subjects bit at 10-mm incisal separation with slow, habitual and fast biting speeds, and in the second experiment, subjects bit with their habitual speed at 10- and 30-mm incisal separations. The activities in the MA and AT muscles were assessed with surface electromyography, and the bite force was recorded by a force sensor placed beneath the chewing gum. Peak bite forces and associated MA amplitudes were increased significantly as biting speed was increased (P's < .05). Anterior temporalis amplitude was significantly increased during fast biting compared to slow and habitual biting (P's < .001). At 30-mm incisal separation, both peak bite force and AT amplitude were significantly increased, whereas MA amplitude was significantly decreased, compared to those at 10-mm separation (P's < .05). Biting off food quickly with incisor teeth results in larger activities in both MA and AT muscles. In addition, biting a large piece of food resulted in increased activity of AT muscle. Both conditions could be injury stimulator for jaw muscles.

Assessment of the relationship between masticatory performance, occlusal contact area, chewing time and cycles, and gastric emptying scintigraphy in dentate subjects.

BACKGROUND: Good mastication is thought to help digestion in the stomach, hence promoting the health of the gastrointestinal system. However, the correlation between masticatory and gastric function has been controversial. This is partly explained by different food types used to assess the performance of the two organs. Recently, frankfurter sausage has been proposed to be suitable for both masticatory performance and gastric emptying tests. OBJECTIVES: To examine the relationship between masticatory performance, occlusal contact area, chewing time and cycles, and gastric emptying scintigraphy parameters in healthy dentate adults. MATERIALS AND METHODS: Forty healthy subjects (15 men: 25 women, age 23.9 ± 3.8 years) underwent masticatory performance tests and gastric emptying scintigraphy using frankfurter sausage as a test food. Masticatory performance was calculated as the median particle size (MPS) of chewed frankfurter sausage cubes after 30 chewing cycles. Gastric emptying scintigraphy was performed using frankfurter sausage mixed with technetium-99 m-labelled microwaved egg meal. Cumulative occlusal areas of contact-near contact (cACNC) were determined by silicone bite registration and image-analysed. Chewing time and cycles before swallowing were also recorded. RESULTS: No significant differences in MPS, cACNC, chewing time and cycles, or gastric emptying parameters were observed between gender. Bivariate correlation showed masticatory performance, occlusal contact area, chewing time and cycles were not correlated with gastric emptying parameters (P > 0.05). CONCLUSION: Using the same test food to assess the masticatory and gastric function in dentate subjects, the present study showed that masticatory performance, occlusal contacts, chewing time and cycles did not affect gastric emptying.

Effect of chewing rate on meal intake.

Fast eating has been shown to increase the risk of overweight in both children and adults. The objectives of the present study were to investigate the correlation between chewing rate and the number of chews per mouthful and to evaluate if they were associated with the weight of meal intake. Thirty healthy subjects, aged 18-24 yr, ate a test lunch at their habitual speed until they felt satiated. The activities of masseter and suprahyoid muscles were recorded to determine the number of chews and the moment of swallowing. The weight of meal intake was recorded along with body mass index (BMI), chewing rate, number of chews per mouthful, meal duration, ingestion rate, hunger, and food preference levels. The mean weight (±SD) of meal intake, chewing rate, and number of chews per mouthful were 261.4 ± 78.9 g, 94.4 ± 13.5 chews min-1 , 19.2 ± 6.4 chews per mouthful, respectively. Chewing rate was not correlated with the number of chews per mouthful. The multivariable linear regression showed that meal intake was significantly positively associated with chewing rate, meal duration, and BMI, but inversely associated with the number of chews per mouthful (adjusted R2 = 0.42). It was concluded that the number of chews was not associated with chewing rate but meal intake was explained by both reduced number of chews and increased chewing rate.

Effect of chewing speed on energy expenditure in healthy subjects.

OBJECTIVE: The aim of the study was to investigate the effect of rate of chewing on energy expenditure in human subjects. MATERIALS AND METHODS: Fourteen healthy subjects (aged 18-24 years) within the normal range of BMI participated in a cross-over experiment consisting of two 6-min sessions of gum chewing, slow (∼60 cycles/min) and fast (∼120 cycles/min) chewing. The resting energy expenditure (REE) and during gum chewing was measured using a ventilated hood connected to a gas analyzer system. The normality of data was explored using the Shapiro-Wilk test. The energy expenditure rate during chewing and the energy expenditure per chewing cycle were compared between the two chewing speeds using Wilcoxon signed ranks tests. RESULTS: The energy expenditure per chewing cycle during slow chewing (median 1.4, range 5.2 cal; mean 2.1±1.6 cal) was significantly higher than that during fast chewing (median 0.9, range 2.2 cal; mean 1.0±0.7 cal) (p < 0.005). However, the energy expenditure rate was not significantly different between the two chewing speeds (p > 0.05). CONCLUSIONS: The results of this study suggest that chewing at a slower speed could increase the energy expenditure per cycle and might affect the total daily energy expenditure.

Perinatal taurine exposure programs patterns of autonomic nerve activity responses to tooth pulp stimulation in adult male rats.

Perinatal taurine excess or deficiency influences adult health and disease, especially relative to the autonomic nervous system. This study tests the hypothesis that perinatal taurine exposure influences adult autonomic nervous system control of arterial pressure in response to acute electrical tooth pulp stimulation. Female Sprague-Dawley rats were fed with normal rat chow with 3% ß-alanine (taurine depletion, TD), 3% taurine (taurine supplementation, TS), or water alone (control, C) from conception to weaning. Their male offspring were fed with normal rat chow and tap water throughout the experiment. At 8-10 weeks of age, blood chemistry, arterial pressure, heart rate, and renal sympathetic nerve activity were measured in anesthetized rats. Age, body weight, mean arterial pressure, heart rate, plasma electrolytes, blood urea nitrogen, plasma creatinine, and plasma cortisol were not significantly different among the three groups. Before tooth pulp stimulation, low- (0.3-0.5 Hz) and high-frequency (0.5-4.0 Hz) power spectral densities of arterial pressure were not significantly different among groups while the power spectral densities of renal sympathetic nerve activity were significantly decreased in TD compared to control rats. Tooth pulp stimulation did not change arterial pressure, heart rate, renal sympathetic nerve, and arterial pressure power spectral densities in the 0.3-4.0 Hz spectrum or renal sympathetic nerve firing rate in any group. In contrast, perinatal taurine imbalance disturbed very-low-frequency power spectral densities of both arterial pressure and renal sympathetic nerve activity (below 0.1 Hz), both before and after the tooth pulp stimulation. The power densities of TS were most sensitive to ganglionic blockade and central adrenergic inhibition, while those of TD were sensitive to both central and peripheral adrenergic inhibition. The present data indicate that perinatal taurine imbalance can lead to aberrant autonomic nervous system responses in adult male rats.

Relief of palatal injection pain by liposome-encapsulated 2% lignocaine prepared by ultrasonic dental scaler.

Injections into the palate are common in dental treatment and are unpleasant for the patient. A liposomal encapsulation technique was developed to improve the efficacy of 2% lignocaine dental injection so that it could be used as a topical anaesthetic. Liposome-encapsulated 2% lignocaine was prepared as needed by sonicating 2% lignocaine hydrochloride dental injection (with 1:100,000 adrenaline) with a lipid mixture using a dental ultrasonic scaler for 1 min. The time to onset and time to take effect were calculated by a pinprick test in the palatal mucosa in 10 normal subjects. In another experiment, the preparation was tested in a further 22 subjects for its pain-relieving effect during a standard palatal injection, and compared with 18% benzocaine/2% tetracaine gel. The results showed that the mean (SD) time to onset and time to take effect of the liposome-encapsulated 2% lignocaine were 39.0 (21.4) and 157.5 (2.3)s, respectively, and the mean (SD) pain score measured on a visual analogue scale (VAS) during injection was 4.1 (2.3)cm. After the application of the gel the corresponding measurement was 4.8 (2.8)cm (p=0.045). The encapsulation of 2% lignocaine dental injection in liposomes by a dental ultrasonic scaler was effective in improving the efficacy of the anaesthetic for topical application.

Determination of chewing efficiency using muscle work.

OBJECTIVE: A new method was proposed to evaluate 'true' chewing efficiency in which the 'cost' of chewing was accounted for. DESIGN: Twenty-three subjects were asked to chew an almond for 5 cycles, after which the chewed particles were air-dried and passed through a 1.4-mm aperture sieve. The activity of both superficial masseter muscles was simultaneously recorded with surface EMG. Integrated EMG (IEMG) was used to calculate burst amplitude, burst duration and maximum voluntary contraction (MVC). The percentage weight of particles passing the sieve was used to represent the conventional chewing efficiency (or masticatory performance). Muscle work (integral of IEMG bursts), muscle effort (muscle work normalized to maximum work) and masticatory effectiveness (the ratio between masticatory performance and muscle work) were also calculated. RESULTS: The results showed that (1) masticatory performance was significantly correlated with muscle work (R=0.45; p<0.005), MVC (R=0.31; p=0.04), but not correlated with muscle effort; (2) masticatory effectiveness was significantly correlated with MVC (R=0.58, p<0.001), but not correlated with masticatory performance. CONCLUSION: Persons with good masticatory performance were not necessarily effective (or efficient) chewers. They seemed to have larger MVCs and use more muscle work during the chewing task.