Hard Food Research Articles

Biological Reconstruction of the Temporomandibular Joint by Chondro-Osseous Graft

This study includes 35 children treated by reconstruction of the temporomandibular joint (TMJ) by chondro-osseous graft harvested from iliac crest for management of 2 diseases; the first one was ankylosis of the TMJ. There were 25 cases of 9 girls and 16 boys, and there were 10 cases of hypoplasia of the TMJ of first-arch dysplasia syndrome or hemifacial microsomia, of which 4 were females and 6 were males. Their ages ranged between 4 and 13 years (mean, 8.5 years); follow-up of the patients ranged from 3 to 5 years. All patients showed good result and without recurrence of ankylosis or restriction of mouth opening, and growth of the face was acceptable and without using osteotomies for correction of jaw relationship or distraction techniques.Experimental studies on rabbits were performed to prove the condyle as growth center and after excision of the head of condyle and disk in newly growing rabbits of 3 months of age; after 3 months of follow-up, we observed severe deformity of the rabbits' mandible, and the mandible deviated to the affected side on the first experiment. In the second experiment, reconstruction of the TMJ and condyle of the rabbits by chondro-osseous graft harvested from iliac crest of the same rabbit was carried out in 8 animals to assess the viability and value of chondro-osseous graft to replace the TMJ. After 3 months, all animals were killed. Postmortem studies were done to assess the healing process of the graft or any resorption of the graft. Histological studies of the graft showed 4 layers: the first articular layer was thick because of functional demand of masticatory process for hard food of rabbits; the second layer was the granular mesenchymal stem cells layer, very active and multiple layers that represent the proliferative layer; the third layer showed conversion of cartilage cells to osteoid cells, and the fourth layer was the osteoid layer. On follow-up of clinical cases, the graft was continued for functional demand of growth, repair, and remodeling of the condyle.

A Conceptual Collaborative Health Test Library in Cloud-A trial on the Relevance of the Taiwanese Students' Ability of Mastication and Dietary Behavior

Problem: The more interaction feedbacks between student and teacher, the higher quality of learning will be obtained. Originally, the formal evaluation approach is executed by a test with feasible and smart questions. However, the test question design will waste most of the teacher’s time. Method: In order to decrease the pressure for preparing school courses and promote the quality of the test questions, it is feasible for implementing a sharing platform to collect test questions among teachers. Furthermore, instructors can refer to other sharing contents as well as copy original questions by citing sourced teachers. It is also possible for instructors to modify original test questions into better ones. Based on the software-as-a-service (SaaS) concept, the proposed sharing platform opens and serves with cloud computing service through some Web Services components in the Internet. When the test library collects a large amount of the questions from most instructors by years, a knowledge management will be generated by itself. The more learning feedbacks from students, the higher assessment validity will gain. A trial on the relevance of the Taiwanese Students' ability of mastication and dietary behavior was test. Results and Conclusion: Based on Google’s success experiences, such a proposed mechanism can be achieved in the Internet undoubtedly. Meanwhile, an official health elearning web site for K1-K9 education in Taiwan achieved this goal at the end of 2011. As the trial test results, there were significant differences in the group of ‘I don’t have breakfast regularly’ and the others, the group of ‘I can’t chew hard food’ and the others, and the group of ‘I am happy every day’ and the others in sugar elution rate.

보툴리눔 A형 독소가 저작효율에 미치는 영향

This study was aimed to evaluate the masticatory efficiency after botulinum toxin type A (BTX-A) injection during 12 weeks using objective and subjective test. Also, we compared the difference of masticatory efficiency between group that injected into the masseter muscle only (M-group) and group that injected into the masseter and temporalis muscle (M-T group). The mixing ability index (MAI) was used as the objective indicator, and visual analogue scale (VAS) and food intake ability (FIA) index were used as the subjective indicators. It was concluded that masticatory efficiency was significantly lowered after a BTX-A injection into the masticatory muscle, but it gradually recovered in a predictable pattern by the 12 weeks. The disturbance of subjective masticatory efficiency was lasted longer than objective masticatory efficiency. The masticatory efficiency was lower in M-T group than M group. It was statistically significant in the VAS and FIA at 4 weeks, but the MAI showed no significancy. After 4weeks, there was rapid recovery of muscle function in M-T group, and the difference between two groups was not significant. It could be concluded that there will be no serious disturbance of mastication compared to injection is done only into the masseter muscle, even if injection is done into the masseter and temporalis muscle in dose of this study. According to the food properties, it was confirmed that people feel more discomfort on taking hard and tough foods after BTX-A injection and not only hard foods, but also intake of soft and runny foods were influenced by botulinum toxin injection.

Chewing Deficiencies in Adults with Multiple Untreated Carious Lesions

Persons who have multiple untreated carious lesions are at high risk of chewing difficulties and consequently an unhealthy diet, but few data are available on the impact of untreated caries on mastication in adults. This study in adults with multiple untreated caries lesions aimed to evaluate chewing deficiencies using physiological and psychosocial indicators. Forty-five patients, mean (±SD) decayed teeth 11.5 (±5.2), and 20 fully dentate caries-free subjects were observed during mastication of raw carrot and two jelly model foods differing in hardness. Criteria for chewing evaluation were carrot bolus granulometry, food refusals, chewing activity (chewing time, number of chewing cycles, chewing frequency) and oral health-related quality of life (GOHAI). Dental status was characterized by caries experience (DMFT) and posterior functional pairs of teeth. Adults with multiple untreated caries lesions suffered from chewing deficiencies, demonstrated by a decrease in food comminution related to the number of posterior functional teeth, food selection and functional alterations in oral health-related quality of life. The ability to adapt chewing activity to food hardness was preserved in this group. Further studies should be conducted to determine whether chewing function could be improved after dental treatment.

Mechanisms and causes of wear in tooth enamel: implications for hominin diets

The wear of teeth is a major factor limiting mammalian lifespans in the wild. One method of describing worn surfaces, dental microwear texture analysis, has proved powerful for reconstructing the diets of extinct vertebrates, but has yielded unexpected results in early hominins. In particular, although australopiths exhibit derived craniodental features interpreted as adaptations for eating hard foods, most do not exhibit microwear signals indicative of this diet. However, no experiments have yet demonstrated the fundamental mechanisms and causes of this wear. Here, we report nanowear experiments where individual dust particles, phytoliths and enamel chips were slid across a flat enamel surface. Microwear features produced were influenced strongly by interacting mechanical properties and particle geometry. Quartz dust was a rigid abrasive, capable of fracturing and removing enamel pieces. By contrast, phytoliths and enamel chips deformed during sliding, forming U-shaped grooves or flat troughs in enamel, without tissue loss. Other plant tissues seem too soft to mark enamel, acting as particle transporters. We conclude that dust has overwhelming importance as a wear agent and that dietary signals preserved in dental microwear are indirect. Nanowear studies should resolve controversies over adaptive trends in mammals like enamel thickening or hypsodonty that delay functional dental loss.

Dysphagia in Duchenne muscular dystrophy assessed by validated questionnaire

Duchenne muscular dystrophy (DMD) leads to progressive muscular weakness and death, most typically from respiratory complications. Dysphagia is common in DMD; however, the most appropriate swallowing assessments have not been universally agreed and the symptoms of dysphagia remain under-reported. To investigate symptoms of dysphagia in DMD and to determine the potential of the validated Sydney Swallow Questionnaire (SSQ) to diagnose dysphagia in this patient group. Three participant groups completed the SSQ and the results were compared: nine DMD participants with dysphagia, six DMD participants without dysphagia and 12 healthy controls. The questionnaire scores for dysphagic DMD participants were significantly higher than for non-dysphagic DMD participants (p = 0.039) and for healthy controls (p ≤ 0.001). The diagnostic ability of the questionnaire was good for detecting dysphagia in participants with DMD (receiver operating characteristic (ROC) area under the curve = 0.89, p = 0.013), with a cut-off score of 224.5 (13.2%) giving a sensitivity of 0.78 and a specificity of 0.83 for determining dysphagia. Dysphagic participants rated time to eat a meal, swallowing hard food, swallowing thick liquids and needing to cough up or spit during meals with the highest severity of all questionnaire items. Results of the questionnaire by item are presented to inform the clinician of the symptoms of dysphagia in DMD. DMD leads to pervasive symptoms of dysphagia. The simple SSQ is a clinically informative assessment tool for patients with DMD.

Association between hypertension status and the screening test for frailty in elderly community-dwelling Japanese

To clarify the possible association of frailty with hypertension prevalence, treatment and blood pressure (BP) control in the elderly, we conducted a screening survey of 1091 elderly community-dwelling subjects aged ≥65 years, using data from public health check-ups and frailty was determined by a 25-item questionnaire, the Basic Checklist for Frailty (BCF). The significance of differences in the association of BCF categories or BCF items with each hypertension status was analyzed using multiple logistic regression analysis after adjusting for age, sex and possible confounding underlying chronic conditions. A total of 63% of subjects were hypertensive (BP≥140/90 mm Hg), and of those, 85% were receiving antihypertensive treatment, and 56.0% of those receiving treatment had controlled BP (<140/90 mm Hg). BCF categories that showed an independent association with hypertension status were 'impaired walking status' and absence of 'impaired nutritional status' for prevalence of hypertension, 'impaired instrumental activity of daily living status' and 'impaired nutritional status' for untreated hypertension among hypertensives and 'impaired oral function' for BP-uncontrolled hypertension among treated hypertensives. In addition, BCF items that showed an independent association were 'inability to walk for more than 15 min without rest' and absence of 'Body mass index (BMI) <18.5 kg m(-2') for prevalence of hypertension, 'weight loss of more than 2-3 kg in the past 6 months' for untreated hypertension, and 'difficulty eating hard food' for BP-uncontrolled hypertension. These observations indicate that assessment of these specified frailty categories and/or items may be useful for evaluating hypertension status in elderly community-dwelling subjects.

Homoplasy and thick enamel in primates

Traditionally, thick enamel has often been used to infer durophagy (i.e., hard nut and seed consumption) in extinct hominins. These inferences are based on the hypothesis that thick enamel is primarily an adaptation to prevent tooth fracture or chipping resulting from high-stress loads produced during the mastication of large hard foods. An alternative view argues that thick enamel may aid in maintaining tooth function in the face of gradual dental wear from grit, phytoliths and acid, which may be found in foods of widely varying hardness. We use estimates of primate dietary abrasiveness and recorded lifespan to test the hypothesis that enamel thickness is selectively responsive to lifetime dental wear resistance. We use data from the literature to relate enamel thickness to measures of dietary abrasiveness, diet profiles, and longevity for 17 primate species and performed linear regression using several combinations of these variables. We found a positive association between lifetime dietary wear and enamel thickness, suggesting that thick molar enamel in primates may have evolved as a means to resist wear apart from selection to resist tooth fracture. Assuming our estimates of lifetime dietary wear are accurate, we caution against ascribing thick enamel solely to the presence of hard-object feeding in paleoanthropological contexts without also considering primate lifespan and other aspects of feeding ecology.

Correlations Between Hardness of Food and Craniodental Traits in Nine Myotis Species (Chiroptera, Vespertilionidae)

Absract We studied 8 skull and 42 dental characters in nine Myotis species (M. myotis, M. blythii, M. bechsteinii, M. dasycneme, M. emarginatus, M. nattereri, M. daubentonii, M. brandtii, M. mystacinus) to analyze correlations between hardness of food and skull and dental traits. Contrary to the common bat pattern, Myotis that are specialized on hard-shelled dietary items tend to have relatively narrow skull and long tooth rows. The dentition of durophagous Myotis is composed by relatively enlarged second and reduced third molars.

Analysis of Masseter Activity Patterns Using TP Values during Chewing of Foods with Different Shapes and Textural Properties

AbstractThe present study examined the ability of physiological parameters of chewing to discriminate between six foods of differing shapes and textural properties. Parameters were measured from masseter electromyograms, which were recorded from healthy and young subjects while they chewed the test foods. Analysis of conventional parameters showed that the number of chewing cycles dropped by 8.8 cycles upon a 100‐kPa increase in food fracturability and by 6.6 cycles upon a 5.0‐kJ/m3 increase in food adhesiveness. Analysis of the newly developed parameters showed that a 100‐kPa increase in food hardness increased the T25, T50 and T75 values by 0.015, 0.020 and 0.021 points, respectively, whereas a 100‐kPa increase in the food fracturability decreased the T25 and T50 values by 0.061 and 0.070 points, respectively. The results suggest that combining several physiological parameters will enhance discrimination between foods because individual parameters are sensitive to different food properties.Practical ApplicationsTogether with other measures, analyzing the activity of the masseter, a muscle responsible for closing the jaw, can provide objective information about food texture. The present study used electromyography to examine the quantitative relationships between various physiological parameters associated with masseter activity during chewing and the textural properties of food. The study focused on everyday foods rather than the model foods that are usually tested in laboratory studies. In addition to analyzing the textural properties (such as hardness and adhesiveness) using conventional physiological parameters, we also developed new parameters, TP values, to assess the masseter activity patterns specifically. The combined use of these physiological parameters is expected to aid clinicians and the food industry in their interactions with individuals who, owing to their age and sequelae of cerebrovascular diseases, have particular difficulty verbalizing their experience of chewing foods.

The Effect of Varying Implant Position in Immediately Loaded Implant-Supported Mandibular Overdentures

This study was carried out to evaluate the effect of varying implant position in immediately loaded implant-supported mandibular overdentures on peri-implant bone density, muscle activity, and patient satisfaction. Fourteen completely edentulous patients were selected for the study. After complete denture construction, patients were divided into 2 equal groups. Four dental implants were installed bilaterally in the interforaminal region in the first group, while in the second group, 4 dental implants were inserted bilaterally: 2 in the interforaminal region and 2 in the first molar area. Immediately after suturing, telescopic abutments were screwed to the implants, and the retaining caps were picked up into the fitting surface of the lower denture, which was delivered to the patient. Patients were recalled for radiographic bone density evaluation just after denture delivery and then at 3, 6, and 12 months thereafter. Muscle activities of masseter and temporalis muscles as well as patient satisfaction were also evaluated. The results of the study showed a high success rate approximating 98.2% of the immediately loaded implants. The electromyographic (EMG) records of both muscles in group 1 were significantly higher during chewing hard food after 3 months compared with group 2 (P < .05). Bone density changes were comparable in the 2 groups except at the end of the follow-up period, when group 2 showed a significant increase in peri-implant bone density values of the posteriorly placed implants compared with group 1 (P < .05). From the results of this study, it may be concluded that wide distribution of immediately loaded implants used for supporting mandibular overdentures through posterior placement beyond the interforaminal area results in a favorable response in terms of increased peri-implant bone density as well as decreased EMG activity of masseter and temporalis muscles.

The Effect of Food Hardness on the Development of Dental Caries in Alloxan-Induced Diabetic Rats

We have previously shown that dental caries may be produced in diabetic rodent models fed with noncariogenic standard diets; however, many studies usually add large amounts of sugar to the diet to induce dental caries. Moreover, the physical properties of cariogenic diets have been reported as an important factor in the formation of caries. The aim of this study was to clarify the effect of the hardness of non-cariogenic diets on the development of dental caries in diabetic rodents. Seven-week-old female F344 rats were divided into 4 groups: intact rats fed with a standard pelletized or powdered diet and alloxan-induced diabetic rats fed with a standard pelletized or powdered diet. All of the rats were sacrificed at 52 weeks of age for morphological examinations on their dental tissue. Dental caries had developed and extended to all the molars in the diabetic rats that were fed with both the pelletized and powdered diets. Moreover, the lesion was significantly enhanced in the powdered diet group compared to that in the pelletized diet group. In conclusion, food hardness is an important factor influencing the development of dental caries in diabetic rats.

Time Course Analysis of Influence of Food Hardness on Head Posture and Pitching of Head during Masticatory Movement

The purpose of the present study was to investigate the relationship between mastication and head posture using foods with different degrees of hardness. A total of 12 healthy, dentulous volunteers participated in the study. Each participant was required to chew two types of gummy candy with two levels of hardness while sitting upright. Measurements were conducted using an optoelectric jaw-tracking system with 6 degrees of freedom (Gnatho-Hexagraph II JM-2000®). The horizontal plane perpendicular to the direction of gravitational force served as the reference plane. Analysis of the gradient of the Frankfurt plane (head posture) and pitching of the head during masticatory movement was conducted. The influence of the type of test food on these parameters was evaluated during mastication. During stable mastication, the gradient of the Frankfurt plane was 4.66 degrees on average, close to the horizontal plane. The time course of the Frankfurt plane gradient revealed a tendency toward dorsal flexion during the first to middle phases of mastication, and a tendency toward ventral flexion during the middle to last phases, regardless of the hardness of the test food. The participants were divided into two groups based on change in head posture during chewing. The results showed while there was no change in head posture in the group with marked pitching of the head, head posture did change in the group with little pitching.

The Study in the Toxic Effects of the Material Bisphenol A at Long Time Exposure

Bisphenol a (BPA), is a chemical that has been used for more than 40 years in the manufacture of many hard plastic food containers such as baby bottles and reusable cups and the lining of metal food and beverage cans, including canned liquid infant formula. Therefore, it is very necessary to study its health risk and ecological risk. In this paper, four typical estrogen acceptor genes (AHR1, ESR1, VTG1 and VTG3) in female zebrafish liver were studied to assess the low dose and chronic effects of bisphenol A (BPA), with the method of quantitative real-time RT-PCR, and the ability of self regulation and repair of these genes were also discussed. The results showed that these genes could be induced even at 15 ug/L BPA, and VTG 3 was the most sensitive gene. VTG 3 and VTG 1 had obvious self repair and adjustment ability when BPA risk was removed. No monotonic dose-effect relationships of BPA were also found at this study.

Drosophila melanogaster larvae control amylase secretion according to the hardness of food

Drosophila melanogaster larvae excrete amylase and perform external digestion of their food. In this study, to investigate whether their external digestion ability varies in response to changes in the external environment, we measured the relative amount of amylase excreted by larvae using a new method: the iodine starch agar method (ISAM). Analysis using this method revealed that the amount of amylase excreted by larvae increased in accordance with the increase in the agar concentration. In addition, we investigated the effect on the larval growth rate of adding amylase to the diet. Pupation occurred 24 h later in food containing 1% amylase than in food containing no amylase. These results suggest that the larvae adjust their amylase excretion in response to changes in the external environment, and that its level has a marked influence on the larval growth rate.

Non-Surgical Management of Mandibular Molar with Multiple Intra–oral Sinus Tracts: A Case Report

Multiple intra-oral sinus tracts of dental origin are an uncommon condition. Patients with this condition may undergo surgical extraction, biopsies and antibiotic regimens, but all of them fail with the recurrence of the sinus tract. A proper diagnosis and management are important, to avoid any complications. This case report has described the conventional root canal treatment of a patient who had three distant intra-oral sinuses which had occurred due to an intact tooth with pulp necrosis, who had a history of accidentally biting on a hard food object and having a periapical radiolucency which indicated a chronic periradicular abscess. At follow up examination, the tooth was found to be asymptomatic and radiographically, it showed repair of the lesion.

Chewing ability and associated factors in a Sudanese population

This study aimed to assess self-reported chewing ability among a sample of Sudanese adults and to identify factors associated with impaired oral function. A total of 1,888 adults (≥16 years old) attending outpatient clinics in Khartoum State were included. Subjective chewing ability was assessed by interviewing participants on chewing complaints and perceived difficulty of chewing 15 common Sudanese foods. Pearson and multivariate analyses were used to examine relationships between chewing ability and characteristics obtained from interviews and clinical examination. Chewing complaints were reported by 33.5% of subjects; 15.2-33.4% had perceived difficulty of chewing hard foods, whereas only 1.5-6.9% had difficulty eating soft foods. The likelihood of chewing complaints was higher in people with dry mouth, <20 teeth, tooth decay, poor self-rated oral health, perceived difficulty of chewing, and higher oral health-related quality of life (OHRQoL) scores. Individuals with <20 teeth, poor self-rated general health, and higher OHRQoL scores were all more likely to have perceived difficulty of chewing certain foods. Impaired chewing ability was rather highly prevalent among Sudanese adults. Addressing factors such as dry mouth and tooth loss/decay, which have been identified to be associated with impaired oral function, might help to decrease the risk of omission of essential foods from the diet and improve OHRQoL.

Bodyweight Assessment of Enamelin Null Mice

The Enam null mice appear to be smaller than wild-type mice, which prompted the hypothesis that enamel defects negatively influence nutritional intake and bodyweight gain (BWG). We compared the BWG of Enam−/− and wild-type mice from birth (D0) to Day 42 (D42). Wild-type (WT) and Enam−/− (N) mice were given either hard chow (HC) or soft chow (SC). Four experimental groups were studied: WTHC, WTSC, NHC, and NSC. The mother's bodyweight (DBW) and the average litter bodyweight (ALBW) were obtained from D0 to D21. After D21, the pups were separated from the mother and provided the same type of food. Litter bodyweights were measured until D42. ALBW was compared at 7-day intervals using one-way ANOVA, while the influence of DBW on ALBW was analyzed by mixed-model analyses. The ALBW of Enam−/− mice maintained on hard chow (NHC) was significantly lower than the two WT groups at D21 and the differences persisted into young adulthood. The ALBW of Enam−/− mice maintained on soft chow (NSC) trended lower, but was not significantly different than that of the WT groups. We conclude that genotype, which affects enamel integrity, and food hardness influence bodyweight gain in postnatal and young adult mice.

&lt;p&gt;&lt;strong&gt;Tooth morphology and food processing in Ophiothrix fragilis (Abildgaard, in O.F. Müller, 1789) and Ophiura albida Forbes, 1839 (Echinodermata: Ophiuroidea)&lt;/strong&gt;&lt;/p&gt;

Based on the main feeding modes of two common European brittlestars, Ophiothrix fragilis and Ophiura albida, the pre­sent study relates the species’ tooth morphology to their function in processing food items of different structural quality. Clusters of grinding dental papillae in the suspension feeding O. fragilis seem most appropriate for loosening compound food items, i.e., food boli, or potentially for grazing. Large triangular teeth are considered to be used as crushing and cut­ting instruments, most likely for processing loosened or broken up food masses into smaller digestible portions. In the mostly predating and scavenging O. albida, sharp and pointy or broad scale-like oral papillae may serve in gripping and fixing live benthic prey organisms or carrion, while the larger spine-like teeth may be applied as carnassial instruments thrusting into the flesh of a prey organism and tearing off pieces. Designating the two species either as grinders and cutters processing compound and hard structured food or as grippers and tearers handling softer textures, still awaits confirmation through feeding experiments and observational documentation.

Difference of the size of average crown width first molar and second molar mandible of the Pawon Man with modern man

Introduction: Pawon Man is prehistoric human who was expected life about 9525-5660 BC and have lived in a Cave Pawon located in Mountain Masigit Village, District Cipatat, Bandung Regency. The purpose of this research to analyzed the difference size of average crown width first molar and second molar mandible Pawon Man with Modern Man. Methods: The research used a descriptive method, so that from 4 archives radiograph Pawon man, can be obtained 14 samples radiographs Cone Beam Computed Tomography first tooth molars and second molars mandible. The research conducted on Ez Implant-3D program using a digital ruler, measurement results then recorded in tabular form, then statistically analyzed using independent two-sample t test. Results: The average size of widht crown first tooth molars and second molars mandible were larger for Pawon Man teeth than Modern Man. Conclusion: The average size of widht crown first tooth molars and second molars mandible were larger for Pawon Man teeth, because Pawon Man eating hard food and rough textured with simple food processing, with transition of culture has changed the dietary and food technology, so the shape of the big teeth are no longer needed.