Lower limb balance, ankle dorsiflexion, orofacial tissue pressure, and occlusal force of rugby players.

This cross-sectional study examined the lower limb balance, ankle dorsiflexion, orofacial tissue pressure, and occlusal strength of rugby players. Twenty-six participants were divided into groups: rugby players (n â€‹= â€‹13) and healthy sedentary adults (n â€‹= â€‹13). Participants underwent an analysis of lower limb balance using a composite score (Y-Balance Test). Ankle dorsiflexion was measured using the Lunge Test. The Iowa Oral Performance Instrument was employed to measure orofacial tissue pressure. Bite force was measured with a dynamometer, and T-Scan assessed occlusal contact distribution. Data were analyzed using the t-test (p â€‹< â€‹0.05) and ANCOVA with age and weight as covariates, where it is possible to verify that these factors did not influence the results obtained. Significant differences were observed in the balance of the right (p â€‹= â€‹0.07) and left (p â€‹= â€‹0.02) lower limbs, where rugby players had lower composite scores. There were significant differences in the right (p â€‹= â€‹0.005) and left (p â€‹= â€‹0.004) lunges, with rugby players showing lower values, as well as lower tongue pressure (p â€‹= â€‹0.01) and higher lip pressure (p â€‹= â€‹0.03), with significant differences to sedentary participants. There was no significant difference in molar bite force and distribution occlusal contacts between groups. Rugby seems to reduce lower limb displacement, cause ankle hypomobility, lead to changes in orofacial tissues, particularly the tongue and lips. This study is significant for identifying significant differences between rugby players and sedentary individuals, providing new insights into the impact of rugby on health and performance, which can benefit sports training and injury prevention.

Bruxism Throughout the Lifespan and Variants in MMP2, MMP9 and COMT.

Bruxism is a masticatory muscle activity characterized by grinding of the teeth and clenching of the jaw that causes tooth wear and breakage, temporomandibular joint disorders, muscle pain, and headache. Bruxism occurs in both adults and children. Clinical characteristics and habits were evaluated in an adult sample. Moreover, we used DNA samples from 349 adults and 151 children to determine the presence of association with specific genes. Genomic DNA was obtained from saliva. The markers rs2241145 and rs243832 (metalloproteinase 2 (MMP2)), rs13925 and rs2236416 (metalloproteinase 9 (MMP9)), and rs6269 (cathecol-o-methyltransferase (COMT)) were genotyped. Data were submitted to statistical analysis with a significance level of 0.05. In adults, in univariate logistic regression, presence of caries, attrition, and use of alcohol were increased in bruxism individuals (p < 0.05). In addition, in adults, there was an association between bruxism and MMP9 (rs13925, p = 0.0001) and bruxism and COMT (rs6269, p = 0.003). In children, a borderline association was observed for MMP9 (rs2236416, p = 0.08). When we performed multivariate logistic regression analyses in adults, the same clinical characteristics remained associated with bruxism, and orthodontic treatment was also associated, besides rs13925, in the AG genotype (p = 0.015, ORa: 3.40 (1.27-9.07)). For the first time, we provide statistical evidence that these genes are associate with bruxism.

The influence of maxillary and mandibular osteoporosis on maximal bite force and thickness of masticatory muscles.

The aim of this study was to examine the bite force and masseter and temporal muscle thickness in individuals with maxillary and mandibular osteoporosis. 72 individuals were distributed into two equal groups: (1) facial osteoporosis and (2) healthy controls. Bite force on the right and left molar regions was recorded with a dynamometer and the highest value out of three measurements was recorded as the maximal bite force. Muscle thickness was measured with a SonoSite Titan ultrasound scanner. Ultrasound images were obtained of the bilateral masseter and temporal muscles at rest and at maximal voluntary contraction. The means of the measurements in each clinical condition were analyzed with multivariate statistical analysis (SPSS 19.0). Student's t test indicated no significant difference for muscle thickness, but indicated significantly lower bite force values in the osteoporosis group (p>0.05). Lower bite force in individuals with facial bone loss demonstrates functional impact of osteoporosis on the complex physiological stomatognathic system.

The influence of maxillary and mandibular osteoporosis on maximal bite force and thickness of masticatory muscles

The aim of this study was to examine the bite force and masseter and temporal muscle thickness in individuals with maxillary and mandibular osteoporosis. 72 individuals were distributed into two equal groups: (1) facial osteoporosis and (2) healthy controls. Bite force on the right and left molar regions was recorded with a dynamometer and the highest value out of three measurements was recorded as the maximal bite force. Muscle thickness was measured with a SonoSite Titan ultrasound scanner. Ultrasound images were obtained of the bilateral masseter and temporal muscles at rest and at maximal voluntary contraction. The means of the measurements in each clinical condition were analyzed with multivariate statistical analysis (SPSS 19.0). Student's t test indicated no significant difference for muscle thickness, but indicated significantly lower bite force values in the osteoporosis group (p>0.05). Lower bite force in individuals with facial bone loss demonstrates functional impact of osteoporosis on the complex physiological stomatognathic system.

Este estudo teve como objetivo analisar a forca de mordida e a espessura dos musculos masseter e temporal em individuos com osteoporose maxilar e mandibular. 72 individuos distribuidos em dois grupos equivalentes: (1) osteoporose facial e (2) controles saudaveis. Forca de mordida nas regioes de molar direita e esquerda foi gravada com o dinamometro e o valor mais alto das tres medidas foi registrado como a forca de mordida maxima. A espessura muscular foi mensurada com ultrassom SonoSite Titan. As imagens de ultrassom foram obtidas dos musculos masseter e temporais bilateral em repouso e em contracao voluntaria maxima. As medias das medidas em cada condicao clinica foram analisadas com a analise estatistica multivariada (SPSS 19.0). Teste t de Student nao revelou diferencas significativas para a espessura musculos, mas indicou valores significativamente mais baixos de forca de mordida no grupo com osteoporose (p> 0,05). Forca de mordida menor em individuos com perda ossea facial demonstra um impacto funcional da osteoporose na fisiologia complexa do sistema estomatognatico.

Ayahuasca Alters Structural Parameters of the Rat Aorta.

Ayahuasca is a hallucinogenic brew traditionally used by Northwestern Amazonian indigenous groups for therapeutic purposes. It is prepared by the decoction of Banisteriopsis caapi with the leaves of Psychotria viridis. Banisteriopsis caapi contains ß-carbolines that are inhibitors of monoamine oxidase and P. viris is rich in dimethyltryptamine, a 5-HT(1A/2A/2C) agonist. Acute ayahuasca administration produces moderate cardiovascular effects in healthy volunteers, but information regarding long-term use is lacking. This study investigated the effects of ayahuasca (2-4 mL/kg) in the rat aorta after acute and chronic (14 days) administration. Ayahuasca caused flattening and stretching of vascular smooth muscle cells and changes in the arrangement and distribution of collagen and elastic fibers. Chronic treatment with the higher dose significantly increased media thickness and the ratio of media thickness to lumen diameter. More research is needed on the cardiovascular function of long-term ayahuasca consumers.

The use of a mandibular repositioning device for obstructive sleep apnea.

The objective of this study was to verify the effect of a mandibular repositioning device (MRD) on polysomnographic parameters and on the mean electromyographic activity of the masseter and temporal muscles in individuals with obstructive sleep apnea syndrome (OSAS). This is a prospective cohort study conducted at multidisciplinary OSAS center in a tertiary referral center. Nineteen individuals with mild or moderate OSAS associated with Mallampati 3-4 were treated with an MRD during sleep. The subjects underwent diurnal electromyography (EM) and nocturnal polysomnography (PSG) examinations both prior and after initial treatment (3 months with MRD for PSG and 6 and 12 months of treatment for EM). The examinations performed at different times were compared. Comparison of the initial and final polysomnography examination revealed a significant mean reduction of apnea-hypopnea index (AHI) from 13.8 to 7.8. The successful treatment rate with the MRD was 52.6%, and the improved treatment rate was 68.4%. Patients with lower pre-treatment AHI presented higher rates of cure. There was no statistically significant change in electromyography examination among different times. The MRD reduced the apnea-hypopnea index in individuals with enlarged base of tongue and mild and moderate OSAS without damaging the function of the masseter and temporal muscles as determined by electromyography.

Aging of masticatory efficiency in healthy subjects: electromyographic analysis--Part 2.

The masticatory process identifies the level of the individual's masticatory ability and provides important information for an adequate diagnosis of the masticatory function. The purpose of this cross-sectional study was to evaluate the influence of age on habitual and non-habitual mastication by means of the values of the ensemble average of masticatory cycles. All volunteers were Brazilian, Caucasian, fully dentate (except for Group I--mixed dentition), aged 7-80 years and divided into five groups: I (7-12 years), II (13-20 years), III (21- 40 years), IV (41-60 years) and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided with respect to gender (20 M/20 F). All subjects were nasal breathers, had normal occlusion and no parafunctional habits or symptoms of temporomandibular dysfunction (RDC/TMD). The masticatory process was analyzed during habitual mastication of peanuts and raisins, and non-habitual mastication of ParafilmM, for 10 seconds each. The resulting electromyographic data were evaluated using SPSS 19.0 software for Windows. ANOVA (analysis of variance) followed by the Duncan test were used to compare the efficiency of the masticatory cycle between age groups. Multivariate analysis (General Linear Models) was used to analyze the effect of age groups and gender on the efficiency of themasticatory cycle, to compare groups (p < 0.05). The results showed that age is directly associated with the changes in masticatory process in healthy subjects.

Aging of masticatory efficiency in healthy subjects: electromyographic analysis--Part 2. / Aging of masticatory efficiency in healthy subjects: electromyographic analysis--Part 2.

The masticatory process identifies the level of the individuals masticatory ability and provides important information for an adequate diagnosis of the masticatory function. The purpose of this cross-sectional study was to evaluate the influence of age on habitual and non-habitual mastication by means of the values of the ensemble average of masticatory cycles. All volunteers were Brazilian, Caucasian, fully dentate (except for Group I--mixed dentition), aged 7-80 years and divided into five groups: I (7-12 years), II (13-20 years), III (21- 40 years), IV (41-60 years) and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided with respect to gender (20 M/20 F). All subjects were nasal breathers, had normal occlusion and no parafunctional habits or symptoms of temporomandibular dysfunction (RDC/TMD). The masticatory process was analyzed during habitual mastication of peanuts and raisins, and non-habitual mastication of ParafilmM, for 10 seconds each. The resulting electromyographic data were evaluated using SPSS 19.0 software for Windows. ANOVA (analysis of variance) followed by the Duncan test were used to compare the efficiency of the masticatory cycle between age groups. Multivariate analysis (General Linear Models) was used to analyze the effect of age groups and gender on the efficiency of themasticatory cycle, to compare groups (p < 0.05). The results showed that age is directly associated with the changes in masticatory process in healthy subjects.

Effect of surgically assisted rapid maxillary expansion on masticatory muscle activity: A pilot study.

BACKGROUND: The aim of the present study was to analyze the electromyographic (EMG) activity of masseter and temporal muscles of adult patients submitted to surgically assisted rapid maxillary expansion (SARME) before and after the surgery. MATERIALS AND METHODS: The sample consisted of 19 adults, with ages ranging from 20 to 47 years (mean 25.4 years), with bilateral posterior cross bite requiring SARME treatment. The electromyographic activity of masseter and temporal muscles was analyzed before treatment (T1) and after the surgical procedure (T2). The mean interval between the two electromyographic analyses was 15 days. RESULTS: The muscular active was electromyographically analyzed during the clinical situation of habitual gum chewing (10 sec), dental clenching (4 sec), mouth opening and closing (10 sec), rest (10 sec), protrusion (10 sec), and right and left laterality (10 sec). The measured differences between T1 and T2 data were evaluated using the paired t-test (SPSS 17.0 for Windows). The electromyographic analysis showed that the activity of the masseter and temporal muscles decreased significantly after the SARME in all the clinical situations after the surgery. CONCLUSION: According to the results of the present study, individuals after SARME surgery presented patterns of electromyographic contraction similar to those developed by dentate individuals during the movements of mandibular excursion.

Action of trivalent chromium on rat liver structure. Histometric and haematological studies

RESUMEN: El cromo trivalente (Cr3+) es un nutriente esencial involucrado en la regulación del metabolismo de carbohidratos, lípidos y proteínas, a través de un estímulo a la acción de la insulina. El objetivo del presente trabajo fue caracterizar histopatológicamente e histométricamente las alteraciones hepáticas de ratas Wistar hembras, provocadas por la administración de cromo III en agua potable. Ratas adultas recibieron ración y agua potable ad libitum, conteniendo 300 ó 500 mg/l de cromo III, durante 4 meses. Los animales control recibieron solo agua y ración. Todos los animales fueron sacrificados con dosis letal de anestésico. Muestras de hígado, fijadas en formol al 10% por 24 h, fueron cortadas a 6 µm y teñidas con hematoxilina y eosina o PAS. Además del examen histopatológico, fueron usadas técnicas histométricas. La sangue fue recolectada y procesada para estudio hematológico. El análisis histopatológico reveló, en la zonas periportal, intermediaria y pericentrolobular, células parenquimatosas con grados variables de vacuolización. Muchos hepatocitos mostraban degeneración baloniforme con núcleos lisados. La vena centrolobular estaba dilatada y congestionada. Se observaron sinusoides dilatados conteniendo eritrocitos. La zona porta mostró fibrosis y proliferación de ductos biliares con pequeñas células. La histometría mostró aumento de los volúmenes de citoplasma y celular, y valores menores para el número de hepatocitos por mm3. Linfopenia fue observada en los animales tratados con 500 mg/l de Cr3+. Estos resultados indican que el cromo III tiene una participación directa en las alteraciones de las estructuras hepáticas.

Acción del Etanol sobre el Epitelio Nasal y Glándulas Septales de Ratas, Durante la Lactancia / Action of Ethanol on Rat Pups Nasal Epithelium and Septal Glands, During Lactation

El consumo materno de etanol durante la lactancia altera la composición de la leche, provoca la aparición de etanol y acetaldehído en la leche y agrava los efectos del etanol en las crías de ratas. De este modo, fueron estudiados los efectos del etanol, administrado a las ratas madres durante la lactancia, sobre el epitelio respiratorio y en las glándulas septales anterior y posterior de las crías lactantes con 21 días de vida postnatal. Las ratas recibieron etanol al 20% en el bebedero, ad libitum durante los 21 días que amamantaron. Los controles recibieron un volumen similar de agua sin alcohol. Las crías fueron sacrificadas en el 21 día. Las cabezas fueran cortadas frontalmente. Los cortes seriados de 6 µm de grosor fueron teñidos con hematoxilina y eosina. Fueron determinados los parámetros nucleares de los epitelios respiratorio y glandular, así como los volúmenes citoplasmático y celular, relación núcleo-citoplasma, densidades numérica y superficial y espesor del epitelio. El peso corporal medio de las crías control fue 34,9 g y en las tratadas 20,2 g. Histologicamente, el epitelio respiratorio se mostró adelgazado en el grupo tratado, constituido por células abundantes y menores, con núcleos menores. La glándula septal posterior presentó ácinos menores. En este trabajo, el etanol indujo un cuadro de hipotrofia epitelial (respiratorio y glandular), indicando una acción directa sobre las células de la mucosa nasal, además de retardar el desarrollo de las crías intoxicadas.

Maternal ingestion of ethanol during lactation alters the chemical composition of milk, results in the appearance of ethanol and acetaldehyde in milk, and exacerbates the effects of ethanol on the rat pups. So that, the effect on respiratory epithelium and anterior and posterior septal glands in 21-day-old suckling pups of ethanol treated mothers was studied. Female rats received dinking water ad libitum containing ethanol (20%) throughout the whole lactation. Control animals received a similar volume of water without ethanol. Lactent rats (21 day-old) were killed by lethal dose of anesthetic. The heads were serially sectioned (6µm thick) in a frontal plain, and stained with haematoxylin and eosin. Cell nuclear parameters were estimated, as well as cytoplasm and cell volume, nucleus-cytoplasm ratio, number and surface densities, and epithelial thickness. Mean body weight of the pups was 34.9 g for the controls and 20.2 g for the treated group. Histologically, the respiratory epithelium was thinner, with more numerous and smaller cells and small nuclei. The posterior septal glands showed smaller acini. In this paper, ethanol induced epithelial (respiratory and glandular) hypotrophy, indicating a direct action in nasal mucous cells, besides retarded development in pups.

Effect of cadmiun on rat maxillary moral junctional epithelium during lactation: efecto del cadmio sobre el epitelio de la zona de union maxilo-molar de ratas durante la lactancia

El cadmio presente en el aire, agua potable y alimentos, afecta la salud de las poblaciones, principalmente en regiones altamente industrializadas. El cadmio afecta la función placentaria, puede atravesar la barrera placentaria y alterar directamente el desarrollo fetal. Puede ser también excretado en la leche. El organismo es particularmente susceptible a la exposición al cadmio durante el período perinatal. Fue estudiado el efecto de la exposición continua, durante la lactancia, a agua potable conteniendo bajos niveles de cadmio, sobre el epitelio de la zona de unión maxilo-molar. Ratas hembras recibieron agua potable ad libitum conteniendo 300mg/l de CdCl2 durante todo el período de lactancia. Los controles recibieron un volumen similar de agua sin cadmio. Ratas lactantes (21 días de edad) fueron sacrificadas con dosis letal de anestésico, sus cabezas separadas, fijadas en alfac por 24 h y la región palatina seccionada frontalmente, al nivel de los primeros molares. Los cortes de 6 µm de espesor fueron teñidos con hematoxilina y eosina. Se estimaron los parámetros nucleares del epitelio, así como los volúmenes citoplasmático y celular, relación núcleo/citoplasma, densidad numérica y superficial y grosor epitelial. El peso medio fue 34,86g para los controles y 18,56g para los tratados. Histológicamente, el epitelio fue más fino, con células más abundantes y menores. El cadmio indujo hipotrofia epitelial, indicando una acción directa sobre la mucosa oral, además de retardo del desarrollo de las crías.