Evaluation of Effective Transmission of Light Through Alveolar Bone: A Preliminary Study

Introduction: The aim of the present study was to determine the effective transmission of 660 and 780 nm lasers through mandibular and maxillary alveolar bones in the buccal-lingual/ palatal direction.Methods: The laser probe was positioned in direct contact with the surface of the anterior, middle and posterior regions of each bone (5 dried maxillae and 5 mandibles) and the power meter was positioned on the bone wall opposite to the radiated wall for the measure of the remaining energy passing through the bone tissue. Ten measurements were performed with each laser at each irradiated point.Results: Transmitted power was significantly higher in bones irradiated with 780 nm laser. Tendencies toward greater average power transmitted in the anterior region of both bones at both wavelengths were also observed.Conclusion: Dosimetry and the choice of light source may be adjusted according to the anatomic region of the alveolar bone to be treated

Connections and neurochemical characterization of neural pathways involved in the control of jaw movements

O núcleo motor do trigêmeo (Mo5) está cercado por um anel de neurônios pré-motores localizados na região h. Estudos demonstram que neurônios que inervam o Mo5 estão distribuídos no tronco encefálico e no prosencéfalo. Após implante de traçador retrógrado no Mo5, verificamos células retrogradamente marcadas no núcleo mesencefálico do trigêmeo (Me5), na região h e em núcleos prosencefálicos como o central da amígdala (CeA), a área hipotalâmica lateral (LH) e o parasubtalâmico (PSTh). Para confirmação, realizamos injeção de traçador anterógrado e investigamos, também, a neuroquímica das projeções. Neurônios do CeA que se projetam para o Mo5 recebem inervação de fibras imunorreativas ao fator liberador de corticotrofina (CFR-ir) e/ou à tirosina hidroxilase (TH-ir); alguns neurônios da LH que se projetam para o Mo5 são imunorreativos à orexina (ORX) e alguns neurônios do PSTh que se projetam para o Mo5 são innervados por fibras TH-ir. O Me5 recebe grande inervação do CeA e moderada da LH e do PSTh, possuindo grande aferência de fibras imunorreativas ao CRF, ORX e THThe trigeminal motor nucleus (Mo5) is surrounded by a ring of premotor neurons defined as the h region. Studies have shown that neurons innervating the Mo5 are located in brainstem and in forebrain nuclei. Through the injection of the retrograde tracer cholera toxin b subunit/CTb in the Mo5, we found retrograde labeled neurons in the brainstem including the h region and the mesencephalic trigeminal nucleus (Me5), and in forebrain nuclei such as the central nucleus of amygdala (CeA), the lateral hypothalamic area (LH) and the parasubthalamic nucleus (PSTh). As control, we injected the anterograde tracer biotin dextran amine and found that these areas project direct or indirectly via the h region or the Me5 to the Mo5. Some CeA neurons that project to the Mo5 receive corticotrophin releasing factor (CRF) and tyrosine hydroxylase (TH) innervation, some LH neurons that project to Mo5 express orexin, and PSTh neurons that project to the Mo5 receive TH innervation. The Me5 is also innervated by CeA, LH and PSTh neurons and by CRF, orexin and TH immunoreactive fiber

Immunohistochemical expression of biglycan and decorin in the pulp tissue of human primary teeth during resorption

Primary teeth are interesting models that can be used to study physiological and pathological processes involving cells and extracellular matrices in hard and soft tissues. This study investigated the expression and distribution of biglycan and decorin-the non-collagenous components of the extracellular matrix-in primary teeth tissue, during physiological root resorption. Thirty healthy human primary teeth were grouped together according to root length: Group I - two-thirds root length, Group II - one-third root length, and Group III - teeth with no root. The streptavidin-biotin-peroxidase immunohistochemical method was used with antibodies against the previously named antigens. The proteoglycans studied were found in the pulp and dentin extracellular matrix in all groups without any differences in the proteins, among the groups. Biglycan was observed mainly in predentin and in pulp connective tissue in the resorption area. In addition, decorin was observed mainly in pulp connective tissue, but near the resorption area. Biglycan and decorin were distributed differentially in the dental tissues. The present immunohistocytochemical data, combined with previously reported data, suggest that these proteoglycans could be involved in regulating the physiological resorption process in healthy primary teeth

VARIANTES MALIGNAS DO AMELOBLASTOMA: FISIOPATOLOGIA,TRATAMENTO E PROGNÓSTICO: UMA REVISÃO LITERÁRIA

<p>O ameloblastoma é um tumor odontogênico de origem epitelial. Este tumor corresponde a cerca de 9 até 11% de todos os tumores odontogênicos. O ameloblastoma pode ser classificado em quatro categorias: multicístico, unicístico, periférico e suas variantes malignas – ameloblastoma metastático e carcinoma ameloblástico. As formas de tratamento e prognósticos variam de acordo com a sua apresentação clínica e histopatológica. Revisar a literatura acerca das variantes malignas do ameloblastoma, suas fisiopatologias, modalidades de tratamento e prognósticos. Foram utilizadas as bases de dados SciELO, PubMeD e Capes Periódicos.  Sendo selecionadas: revisões sistemáticas, literárias, e relatos de casos, no total de 28 artigos filtrados pelo limite temporal dos últimos 10 anos<strong>. </strong>Pesquisas demonstraram casos em que ocorria a metastização do tumor à distância, sendo assim essa variante foi denominada "ameloblastoma metastático", não apresentando diferenças histológicas do ameloblastoma convencional. Uma outra manifestação da patologia, o carcinoma ameloblástico, deve ser reservada para o ameloblastoma que tenha características celulares de malignidade do tumor primário na recorrência ou em qualquer metástase. Para o ameloblastoma maligno não há um tratamento padrão, porém o mais abordado é a ressecção cirúrgica total da lesão, seguida de tratamento concomitante com radioterapia e quimioterapia. Já o carcinoma ameloblástico possui um tratamento controverso, sendo a ressecção cirúrgica a modalidade de tratamento mais utilizada. Em relação ao prognóstico, o ameloblastoma maligno apresenta uma taxa de mortalidade de 25%, com taxa de recorrência elevada de 67,5%. Enquanto o carcinoma ameloblástico, apresenta 19% de mortalidade e recorrência em 21,25% dos casos. De acordo com os resultados, o tratamento de ambos deve ser baseado em sua fisiopatologia e taxa de recorrência. Por fim, quanto mais conservador o tratamento, maior a chance de recidiva, e quanto mais agressivo, melhor o prognóstico.</p&gt

Effects of Dietary Supplementation with Agaricus sylvaticus

This study evaluated the effect of the Agaricus sylvaticus (sun mushroom) on biochemical tests of the plasma and on the morphology of the pancreas in an experimental model of type I diabetes mellitus (DM1) induced by streptozotocin. One gram of dry A. sylvaticus was homogenized and mixed with the chow. Male Wistar rats were allocated as follows: normoglycemic control that received commercial chow; normoglycemic control group that received chow with A. sylvaticus; diabetic group that received commercial chow; and diabetic group that received chow with A. sylvaticus. Weight, food, and water consumption were measured every two days. Blood glucose levels were measured twice a week. After 30 days, the animals were euthanized and blood was collected for the analysis of cholesterol, HDL, triglycerides, blood sugar, glutamic-pyruvic transaminase (GPT), alkaline phosphatase, iron, transferrin, and urea. The pancreas was processed for microscopic analysis. A. sylvaticus modulated the levels of cholesterol, HDL, triglycerides, blood sugar, GPT, alkaline phosphatase, iron, transferrin, and urea to levels similar to those found in the controls and led to compensatory hyperplasia of the islets of Langerhans. A. sylvaticus is potentially beneficial in the control of type 1 diabetes, and it may also prevent pancreas damage

Measurement of effective remnant power in low intensity laser after passage through the buccinator muscle in anatomical human hemifaces

Objective: To determine the effective remnant power after the passage of low intensity laser of two different wavelengths (660 and 780 nm) through buccinator muscle in anatomical hemifaces. Methods: Five human hemifaces were dissected, and a laser was shone in the central region of the muscle with a receiver placed on the opposite side. The hemifaces were irradiated using the same dosimetric parameters (40 mW, 1 W/cm2, continuous mode, 0.04 cm2) and at the same point in every muscle; remnant power was measured for each irradiation. Results: The average remnant power after irradiation with 660 nm (149 ± 15 μW) light was sig-nificantly lower (p<0.0001) than with that of 780 nm (380 ± 40 μW). Conclusion: The LIL of 780 nm presented greater remnant power in comparison to the 660 nm laser after passage through the buccinator muscle, indicating the latter ́s greater penetration capacity