Relationship between chewing ability and high-level functional capacity in an 80-year-old population in Japan

Objectives: To evaluate the association between high‐level functional capacity and chewing in a middle‐old community‐based population. Background: Although basic and instrumental activities of daily living are known to be associated with chewing ability in the elderly, an association between higher levels of competence and chewing ability has not been evaluated in the elderly. Materials and methods: The association between chewing ability using a number of different foods and high‐level functional capacity by the Tokyo Metropolitan Institute of Gerontology was evaluated in 694, 80‐year‐old people residing in Fukuoka Prefecture, Japan. Results: A significant correlation was found, using multiple regression or logistic regression analyses adjusted for various confounding factors, between the number of total chewable foods, hard foods or moderately hard foods, and total functional capacity, instrumental activity, intellectual activity or social role ability. In contrast, the number of slightly hard foods, easily chewable foods and remaining teeth were only partly related to total functional capacity and intellectual activity. Conclusion: High‐level functional capacity including intellectual activity and social role in middle‐old elderly was associated with the ability to chew hard foods than to chew easily chewable foods. Maintenance of chewing ability in elderly might result in better intellectual activity and social role.     

年轻小鼠咀嚼刺激长期改变对焦虑和认知的影响

建立长期增加或减少年轻小鼠切牙的咀嚼刺激模型.通过形态学的观察,研究小鼠下颌骨和咬肌的变化以及大脑皮层和海马的厚度改变;通过行为学实验(旷场实验、高架十字迷宫、新异物体识别和Morris水迷宫实验)观察小鼠认知能力和焦虑情绪的变化;通过高效液相色谱(HPLC)检测小鼠皮层、海马中4种单胺类神经递质(去甲肾上腺素(NE)、肾上腺素(E)、多巴胺(DA)和5-羟色胺(5-HT))的变化,以探讨小鼠焦虑情绪改变的机理;通过荧光实时定量PCR检测小鼠皮层和海马与认知紧密相关的4种基因(BDNF、Synapsin I、NR2B和CREB)的mRNA表达,以研究小鼠认知能力改变的机理.形态学结果显示:各组小鼠下颌骨和咬肌纤维的形态没有影响,各组小鼠皮层和海马的厚度也没有差异.行为学实验结果显示:咀嚼增加组小鼠焦虑倾向低于对照组和咀嚼减少组,各组小鼠短期记忆能力没有统计学差异,咀嚼增加组小鼠空间认知能力优于咀嚼减少组.高效液相色谱结果显示,咀嚼减少组小鼠与咀嚼增加组和对照组相比,去甲肾上腺素在皮层中明显升高(P<0.05).mRNA检测结果显示,咀嚼减少组小鼠4种与认知相关基因的表达量与咀嚼增加组相比都明显下调(P<0.05).上述结果提示,切牙咀嚼刺激的长期增加可以提高小鼠的自主运动能力,降低焦虑程度,提高空间认知能力,上调海马中认知相关基因的表达.切牙咀嚼刺激的长期减少,会降低小鼠的自主运动能力,下调认知相关的基因表达,增加大脑皮层中去甲肾上腺素的含量.     

Elders with implant overdentures: a 22-year clinical report

doi: 10.1111/j.1741‐2358.2012.00628.x Elders with implant overdentures: a 22‐year clinical report Objective: To report on the long‐term survival and prosthodontic maintenance of two edentulous adults with mandibular overdentures supported by hydroxyapatite (HA)‐coated implants. Background: Mandibular implant overdentures are a successful treatment option with positive impact on the quality of life of elderly edentulous adults. Long‐term survival of the implants requires continued rigorous prosthodontic maintenance. Clinical report: Two elderly edentulous adults with mandibular overdentures supported by 2 HA‐coated implants were presented for prosthodontic rehabilitation after 22 years of placement. The implants were osseo‐integrated and surviving at presentation based on accepted criteria. The mandibular implant overdentures suffered recurrent loss of retention and stability. Prosthodontic treatment involving the replacement of defective attachment systems and construction of new sets of mandibular implant overdentures opposing complete maxillary dentures is presented. Conclusion: The long‐term survival of mandibular 2‐implant overdentures requires continued prosthodontic maintenance. A conservative approach in the rehabilitation of two older edentulous adults with mandibular 2‐implant overdentures was described including proper selection of attachment systems.     

Evaluation of satisfaction with masticatory efficiency of new conventional complete dentures in edentulous patients--a survey

doi: 10.1111/j.1741‐2358.2012.00634.x Evaluation of satisfaction with Masticatory efficiency of new conventional complete dentures in edentulous patients. A survey Background: Knowing how patients really feel after treatment is, very often, as relevant as the success rate of the conventional dentures and it can even be the measurement of masticatory function. Aim and objectives: This questionnaire survey aimed to analyse the satisfaction level and masticatory efficiency of patients treated with conventional complete dentures. Design and setting: Thirty edentulous patients were considered in the study. Satisfaction level and masticatory efficiency were analysed based on specific questionnaires for edentulous patients and by a likert rating scale from 0 to 5, at three moments: Prior to treatment (edentulous period), after the insertion of the new dentures and at 30–45 days follow‐up. Materials and methods: Thirty patients including 12 male and 18 female patients (mean age 65 years), who voluntarily came for the services. T‐test was applied at three different levels. Results: The rehabilitation with conventional complete dentures produced an improvement (p < 0.05) in satisfaction level and masticatory efficiency. Conclusion: Thus, those patients who were edentulous previously and dissatisfied with their masticatory ability showed improvement after receiving a new set of conventional complete dentures.     

The environmental efficiency of Wanjiang demonstration area: A Bayesian estimation approach

With the implementation of the strategic policy and the construction of Wanjiang demonstration area recently, the government cares more about the natural environment. To protect the environment of this demonstration area, a quantitative analysis of environmental efficiency and its influencing factors is needed. In this paper, we measure the environmental efficiency of the demonstration area, and then analyze the total factor productivity of the area by Malmquist productivity index through data envelopment analysis (DEA) approach. Through the index and its decomposition, we are able to reveal the changing trend of the environmental efficiency. Moreover, we apply Bayesian estimation approach to analyze the influencing factors of the efficiency and discuss the relationship between these factors and the environmental efficiency. Results show that the efficiency of Wanjiang demonstration area bares a significant difference among constituent cities. Each area should devise proper environmental policy according to its particular circumstance.     

The severity of chewing disorders is related to gross motor function and trunk control in children with cerebral palsy

Abstract

Purpose: The frequency of chewing disorders increases with decreasing level of gross motor function in children with cerebral palsy (CP). Besides its frequency, the severity of chewing disorders is also important. The aim of this study was to determine the relationship between chewing performance level and gross motor function, and trunk postural control in children with CP.

Materials and methods: The study included 119 children with CP (age 2–10 years). Chewing performance level was determined by the Karaduman Chewing Performance Scale (KCPS). The Gross Motor Function Classification System (GMFCS) was used to determine the level of gross motor function. Segmental Assessment of Trunk Control (SATCo) was used to measure trunk control.

Results: Children with spastic CP with a median age of 4?years were evaluated, of which 50.4% were male. The percentages of patients classified to GMFCS levels I to V were 43.7%, 6.7%, 9.2%, 5.0%, and 35.3%, respectively. The median KCPS score was 3 (min?=?0, max?=?4). A good correlation was found between KCPS and GMFCS (p?<?.001, r?=?0.70). Negative, excellent correlations between KCPS and SATCo static, SATCo active, and SATCo reactive postural controls were found (p?<?.001, r?=?–0.75, r?=?–0.77, r?=?–0.79; respectively).

Conclusions: The severity of chewing disorders is related to the level of gross motor function and trunk postural control in children with CP.

Clinical trial number: NCT03241160     

Potency of extract contents from selected tropical chewing sticks against Staphylococcus aureus and Staphylococcus auricularis

Two strains of enteropathogenic Gram-positive bacteria (Staphylococcus auricularis, NIAH 11484 and Staphylococcus aureus, IFO 12732) were tested in vitro for their resistance to extracts from tropical chewing stick species, namely, Garcinia mannii Heck, Masularia accuminata (G. Don) Benth, Zanthoxylum gilletii (DeWild) Waterman, Terminalia glaucescens Plauch ex Benth, Azadiracta indica A. Juss, Anogeissus leiocarpus Guill & Perr and Pseudocedrela kotschyi (Schweinf.). The chewing sticks are normally used for oral hygiene and this is felt to be related to their ability to attack bioagents that could invade the mouth during normal nutrition. Results from our study showed that the antibiotic properties of test chewing stick species vary and are target-microbe-specific. Of the species examined, only T. glaucescens showed appreciable broad antibiotic effect against S. aureus and S. auricularis. Intense antibiotic activity against S. aureus occurred when using a 2.0 g/l extract concentration and a 30-h incubation. T. glaucescens also showed intense activity against S. auricularis at 2.0 g/l concentration, 30-h incubation when all other extracts had lost their potency. A. indica is, however, most effective against S. aureus, showing appreciable antibiotic activity at 0.4 g/l concentration, 30-h incubation. Z. gilletii has no antibiotic activity against any of the test bacteria. The antistaphylococcus compounds in T. glaucescens and A. indica are worthy of isolation and further analyses.     

下颌种植覆盖义齿的生物力学研究进展

口腔生物力学是用生物力学的概念和方法,研究口腔医学中的有关基础性科学问题、解决口腔医学中的临床实际问题、发展口腔临床技术的一门学科。在口腔正畸学、修复学、种植学及口腔颌面外科学等领域存在着大量的生物力学问题,生物力学已成为口腔医学的基础科学之一。传统全口义齿修复常常会出现固位稳定差、咀嚼效率低、患者有疼痛感、适应时间长等情况,很大程度上不能满足患者的修复要求。种植覆盖义齿对于下颌牙槽嵴严重吸收的患者,效果尤为明显。种植覆盖义齿是义齿与种植体之间以不同的附着体作为连接,形成患者可以自行摘戴的种植体支持的覆盖义齿修复。下颌种植覆盖义齿因其能有效地提高下半口义齿的固位性和稳定性、显著提高了患者的咀嚼效率,目前已成为修复下颌牙槽骨严重吸收的无牙颌患者的有效修复方法。本文针对下颌种植覆盖义齿的生物力学研究进展作一综述。     

Monitoring and assessment of ingestive chewing sounds for prediction of herbage intake rate in grazing cattle

Accurate measurement of herbage intake rate is critical to advance knowledge of the ecology of grazing ruminants. This experiment tested the integration of behavioral and acoustic measurements of chewing and biting to estimate herbage dry matter intake (DMI) in dairy cows offered micro-swards of contrasting plant structure. Micro-swards constructed with plastic pots were offered to three lactating Holstein cows (608±24.9 kg of BW) in individual grazing sessions (n=48). Treatments were a factorial combination of two forage species (alfalfa and fescue) and two plant heights (tall=25±3.8 cm and short=12±1.9 cm) and were offered on a gradient of increasing herbage mass (10 to 30 pots) and number of bites (~10 to 40 bites). During each grazing session, sounds of biting and chewing were recorded with a wireless microphone placed on the cows’ foreheads and a digital video camera to allow synchronized audio and video recordings. Dry matter intake rate was higher in tall alfalfa than in the other three treatments (32±1.6 v. 19±1.2 g/min). A high proportion of jaw movements in every grazing session (23 to 36%) were compound jaw movements (chew-bites) that appeared to be a key component of chewing and biting efficiency and of the ability of cows to regulate intake rate. Dry matter intake was accurately predicted based on easily observable behavioral and acoustic variables. Chewing sound energy measured as energy flux density (EFD) was linearly related to DMI, with 74% of EFD variation explained by DMI. Total chewing EFD, number of chew-bites and plant height (tall v. short) were the most important predictors of DMI. The best model explained 91% of the variation in DMI with a coefficient of variation of 17%. Ingestive sounds integrate valuable information to remotely monitor feeding behavior and predict DMI in grazing cows.     

Effect of forage particle length on rumen fermentation,sorting and chewing activity of late-lactation and non-lactating dairy cows

The objective of this study was to determine the effects of varying forage particle length on chewing activity, sorting behavior, rumen pH and rumen fill in late lactation and dry dairy cattle, fed rations with similar physically effective NDF but different mean particle length. Treatments consisted of three diets differing only in geometric mean length of forage: hay (5.40, 8.96 and 77.90 mm, for short (S), medium (M) and long (L) diets, respectively) for Experiment 1 (E1), and straw (10.16, 24.68 and 80.37 mm) for S, M and L diets, respectively, for Experiment 2 (E2). Hay or straw comprised the sole source of forage (50% and 75% of ration dry matter (DM) for E1 and E2, respectively). Both experiments used three rumen cannulated Holstein dairy cows, in late lactation for E1 and dry in E2, with 3 × 3 Latin square designs with 14 day periods. In E1, DM intake (DMI; 18.3 ± 2.1 kg/day; mean ± s.e.), pH (6.4 ± 0.1), time spent eating (280 ± 22.5 min/day), time spent ruminating (487 ± 17 min/day), and total time spent chewing (767 ± 34 min/day) were not different, whereas eating minutes per kilogram of DMI and NDF intake (NDFI) tended to increase linearly as forage length increased. Rumen digesta volume (l; 113.3 S, 117.8 M and 114.4 L ± 17.1) had a quadratic response, and rumen digesta weight tended to respond quadratically; however, differences were numerically small. In E2, DMI (8.3 ± 1.3 kg/day), pH (6.7 ± 0.1), time spent eating (236 ± 23.5 min/day), time spent ruminating (468 ± 45.2 min/day), total time spent chewing (704 ± 67.7 min/day) and minutes per kilogram NDFI were not different, whereas minutes per kilogram of DMI had a trend for a quadratic effect. Rumen digesta volume (111 ± 18.8 l) and weight (103 ± 17.4 kg) were not different. In both experiments, cows sorted against longer particles as determined by a particle length selection index; this behavior increased linearly as particle length increased. Greater forage particle length increased sorting behavior, but had no effect on rumen fermentation or chewing behavior.     

Effects of betel chewing on the central and autonomic nervous systems

Betel chewing has been claimed to produce a sense of well-being, euphoria, heightened alertness, sweating, salivation, a hot sensation in the body and increased capacity to work. Betel chewing also leads to habituation, addiction and withdrawal. However, the mechanisms underlying these effects remain poorly understood. Arecoline, the major alkaloid of Areca nut, has been extensively studied, and several effects of betel chewing are thought to be related to the actions of this parasympathomimetic constituent. However, betel chewing may produce complex reactions and interactions. In the presence of lime, arecoline and guvacoline in Areca nut are hydrolyzed into arecaidine and guvacine, respectively, which are strong inhibitors of GABA uptake. Piper betle flower or leaf contains aromatic phenolic compounds which have been found to stimulate the release of catecholamines in vitro. Thus, betel chewing may affect parasympathetic, GABAnergic and sympathetic functions. Betel chewing produces an increase in heart rate, blood pressure, sweating and body temperature. In addition, EEG shows widespread cortical desynchronization indicating a state of arousal. In autonomic function tests, both the sympathetic skin response and RR interval variation are affected. Betel chewing also increases plasma concentrations of norepinephrine and epinephrine. These results suggest that betel chewing mainly affects the central and autonomic nervous systems. Future studies should investigate both the acute and chronic effects of betel chewing. Such studies may further elucidate the psychoactive mechanisms responsible for the undiminished popularity of betel chewing since antiquity.     

The development of a simple objective test of mastication suitable for older people,using chewing gums

Aims: To develop and assess a simple test for evaluating the mastication of visco‐elastic foods and prosthodontic success subsequent to treatment of older people. Method: The weight lost from chewing gum during mastication tests and the saliva secreted is weighed. The percentage of the original gum weight that is chewed out in a defined number of strokes is termed the Masticatory Effectiveness (ME) Material: Five edentate and three dentate volunteers were selected to provide a range of dental states and age. Four commercially available chewing gums of different origins and perceived hardness were tested, one without sweetener acted as a control for salivary stimulation. Intervention: Pre‐weighed samples of each gum were chewed, each for defined numbers of strokes. The saliva secreted was collected and weighed. The chewed gum was desiccated and the total weight loss of sweeteners chewed out provided an objective measure of chewing performance. Results: Weight loss showed large differences between gums, between subjects and the number of strokes. ME was significantly correlated with salivary secretion rates for two subjects. The interaction between subject and gum was statistically significant, established by an ANOVA model, the value of which is shown for multivariate studies. Differential success between gums of different thickness may provide evaluation of denture stability. Conclusions: Measuring the weight lost from gums during chewing provides a simple test of masticatory effectiveness of visco‐elastic foods. This has particular value both in functional assessment of older people and in physiological research.