Elaboración de modelos dentales didácticos en resina epóxica / Elaboration of didactic dental models in epoxy resin

Los modelos de estudio son un registro fundamental para el diagnóstico, el plan de tratamiento, la presentación de caso y la evaluación del progreso del tratamiento dental; son registros anatomofisiológicos de las arcadas dentarias que sirven para evaluar la dentición en los tres planos del espacio y la oclusión en la relación cúspide-fosa, en una dimensión estática y dinámica. Para obtener los modelos de estudio es imprescindible obtener impresiones totales con diversos materiales de impresión de los arcos dentarios, que reproduzcan fielmente todos los detalles anatómicos, para posteriormente obtener un modelo en yeso piedra. Los modelos obtenidos a partir de una impresión generalmente son a base de yeso odontológico, los cuales a pesar de sus mejoras aún conservan algunas características negativas como: baja resistencia a la fractura por impacto, baja resistencia al desgaste por abrasión, inestabilidad dimensional y radiopacidad que impide la simulación de procedimientos endodóncicos. Con la finalidad de mejorar la simulación en la práctica odontológica, se usa la resina epóxica que puede emplearse en la obtención de modelos, este material es más resistente y presenta una mayor resistencia a la abrasión; además es radiolúcido, por lo que es útil para la réplica de preparaciones y procedimientos de simulación endodóntica. Los detalles de la superficie obtenidos con resina epóxica son superiores a los obtenidos con yeso. El uso de simuladores es una herramienta educativa con la que se favorece la adquisición de ciertas habilidades, destrezas, técnicas y competencias necesarias para la formación de estudiantes o profesionales de odontología. En el presente trabajo se describe la técnica para la elaboración de modelos dentales didácticos en resina epóxica para utilizarlos en la enseñanza de la práctica odontológica (AU)

Study studies are a fundamental record for diagnosis, treatment plan, case presentation and evaluation of the progress of dental treatment. They are anatomo-physiological records of the dental arches to evaluate the dentition in the three planes of space and the occlusion in the cusp-fossa relationships, in a static and dynamic dimension. To obtain the study models, it is essential to obtain total impressions with various impression materials of the dental arches, which faithfully reproduce all the anatomical details, in order to later obtain a stone plaster model. Those obtained from an impression are generally based on dental plaster, which despite its improvements still retain some negative characteristics such as: low resistance to fracture by impact, low resistance to wear by abrasion, dimensional instability and radio opacity that prevents the simulation of endodontic procedures. In order to improve simulation in dental practice, the use of epoxy resin can be used to obtain models, this material is more resistant and has greater resistance to abrasion, it is radiolucent, which makes them Useful for replicating preparations and endodontic simulation procedures, the surface details obtained with epoxy resin are superior to those obtained with plaster. The use of simulators is an educational tool that favors the acquisition of certain abilities, skills, techniques and competencies necessary for the training of the student or professional in dentistry. In the present work, the technique for the elaboration of didactic dental models in epoxy resin to be used in the teaching of dental practice is described.(AU)

Chemosensory representation of first-time oral exposure to ethanol in the orbitofrontal cortex of mice.

Intermittent ethanol consumption changes the neuronal activity of the orbitofrontal cortex (OFC) in rodents, which has been attributed to important participation in the development of addiction, particularly alcoholism. The OFC participates in gustatory sensory integration. However, it is unknown whether this region can encode chemosensory elements of oral ethanol administration independently of the consumption movement (orofacial motor response) when administered for the first time (naïve mice). To answer this question, we used a sedated mouse model and a temporary analysis protocol to register extracellular neuronal responses during the oral administration of ethanol. Our results show an increase in neuronal frequency (in the first 500 ms) when low (0.6, 1, and 2.1 M) and high (3.2, 4.3, and 8.6 M) concentrations of ethanol are orally administered. The modulatory effect of ethanol was observed from low and high concentrations and differed from the tastants. There was consistent neuronal activity independent of the concentration of ethanol. Our results demonstrate a sensory representation of oral ethanol stimulation in the OFC neurons of naïve mice under sedation.

Changes in somatosensory perception induced by trigeminal injury after Maxillofacial Surgical Procedures / Cambios en la percepción somatosensorial inducidos por lesiones trigeminales causadas por procedimientos quirúrgicos maxilofaciales

Abstract Evidence has been reported that shows that somatosensory perception can be altered by a trigeminal injury resulting from maxillofacial surgical procedures. However, the surgical procedures that most frequently cause trigeminal lesions and the risk factors are unknown. In the same way, there is little information on what has been determined in preclinical models of trigeminal injury. This article integrates relevant information on trigeminal injury from both clinical findings and primary basic science studies. This review shows that the age and complexity of surgical procedures are essential to induce orofacial sensory alterations.

Resumen Se han reportado evidencias que demuestran que la percepción somatosensorial puede ser alterada por la lesión trigeminal producto de procedimientos quirúrgicos maxilofaciales. Sin embargo, se desconoce cuáles son los procedimientos quirúrgicos que más frecuentemente producen lesiones trigeminales, y los factores de riesgo. De la misma forma hay poca información sobre lo que se ha determinado en modelos preclínicos de lesión trigeminal. El objetivo de este artículo es integrar información relevante sobre la lesión trigeminal desde los hallazgos clínicos como los principales estudios de ciencia básica. Esta revisión demuestra que la edad y el tipo de procedimiento son fundamentales para inducir alteraciones sensoriales orofaciales, así como los procesos neurobiológicos que subyacen a estos padecimientos.

Sensory, Affective, and Cognitive Effects of Trigeminal Injury in Mice.

PURPOSE: To characterize adequate study of chronic neuropathic orofacial pain induced by a mental nerve injury in a mouse model, we propose a behavioral assessment of its dimensions: sensory, affective, and cognitive. MATERIALS AND METHODS: Trigeminal injury was induced by a chronic mental nerve constriction (MnC). Behavioral tests were conducted to assess the different dimensions of pain and to evaluate the general well-being of mice. RESULTS: Rodents who went through MnC showed signs of mechanical hyperalgesia and increased escape/avoidance behavior. They showed no alterations in general well-being behaviors, yet the injury was sufficient to induce impairment in the ability to adapt to the environmental requirements. CONCLUSIONS: MnC injury is an efficient model for the study of orofacial pain in mice, capable of inducing impairment in the different dimensions of pain. Intensity and temporality of its effects make our model less aggressive, yet effective to generate cognitive impairment. This work provides a solid foundation for the study of the neural circuits involved in the processing of neuropathic orofacial pain.

Multidimensional study of orofacial chronic neuropathic pain: an experimental study in rats

Orofacial neuropathic chronic pain (NCP) is frequently attributed to lesions caused by orofacial surgeries and dental treatments. there are many experimental models available to study orofacial NCP, however, many are extremely painful for the animal due to the amplitude of the innervated region. a previously proposed mental nerve constriction model, mNC, was used in this project. forty wistar rats were randomly divided into two groups: one group included rats with mNC (n=20), and another rats with sham lesions (n=20). through the use of the fixed ratio program and the progressive program, a decrease of motivation for a sweet substance, caused by the lesion, was evaluated. the possibility of alterations in cognitive learning and adaptation abilities was also assessed using the go/no-go behavioral task. the mNC group showed low induced and spontaneously evoked pain responses, as well as a decrease in the motivation for sucrose, a sign of anhedonia. this decrease does not depend on taste processing. finally, although no alterations in the learning-memory process were observed, the mNC group did show alterations when adapting to a new rule.

Curcumina, una alternativa térapéutica para la clínica dental. Parte: antiinflamatorio y analgésico / Curcumin, a therapeutic alternative for the dental clinic (Part I):An anti-inflammatory and analgesic

La curcumina es una sustancia derivada de una planta llamada Curcuma longa. A esta sustancia se le han atribuido diversos efectos terapéuticos. En relación con la clínica dental, se ha observado que, además de ayudaren el control del dolor, ha sido efectiva contra la periodontitis, estomatitis y mucositis pediátrica. El control del dolor e inflamación son aspectos muy importantes para la mayoría de los tratamientos en odontología; la búsqueda de nuevas alternativas analgésicas y antiinflamatorias que, en comparación con las actuales, sean más eficientes, efectivas y tengan menos efectos colaterales es uno de los grandes retos de las ciencias biomédicas. La presente revisión muestra algunas evidencias científicas de los efectos de la curcumina como un antiinflamatorio y analgésico, con el propósito de sentar las bases para futuros estudios clínicos y de ciencia básica que aporten un mayor entendimiento de los procesos celulares, bioquímicos, moleculares, fisiológicos y farmacológicos de la curcumina como una sustancia potencialmente útilen el consultorio dental.

Curcumin is a substance derived from the plant Curcuma longa andone that has been attributed a range of therapeutic eff ects. In dentalpractice, curcumin has not only been found to help with pain control, buthas also been eff ective against periodontitis, stomatitis, and pediatricmucositis. Controlling pain and infl ammation are both very importantaspects of most dental treatments. The search for more effi cient andeff ective analgesic and anti-infl ammatory alternatives with fewerside eff ects compared to those currently used is one of the greatestchallenges for biomedical science. This review presents some of thescientifi c evidence of the eff ects of curcumin, both as an analgesic andan anti-infl ammatory agent, in order to establish the foundations forfurther clinical and basic science studies that will provide a greaterunderstanding of the cellular, biochemical, molecular, physiological,and pharmacological processes of curcumin as a potentially usefulsubstance in dental practice.

Clinical applications of molecular basis for craniosynostosis: a narrative review / Aplicaciones clínicas de las bases moleculares de la craneosinostosis: revisión narrativa

Abstract: cranial sutures are specialized structures composed of the sutural mesenchyme, the overlying scalp, the dura and osteogenic fronts. Each one of these structures express important proteins for osteogenic maturation, membranous ossification of skull bones, and homeostasis of cranial sutures in a differential, spatial and temporal manner. These proteins include fibroblast growth factor (FGF) and its receptors (FGFR), the transforming growth factor beta (TGF-beta), bone morphogenetic proteins (BMPs), as well as transcription factors TWIST and MSX2, among others. The alteration in the expression of one or more of these proteins causes multiple pathological conditions; one of them is the premature closure of one or more cranial sutures, known as craniosynostosis. This malformation is commonly treated with surgery. However, advances in the fields of molecular and cellular biology have allowed to conduct research on some proteins involved in the development of craniosynostosis. The results of these studies can lead to future preventive therapeutic strategies that may be used as a complement to the surgical treatment of craniosynostosis. Possible strategies include the use of specific drugs that can regulate the expression and activation of FGF signaling pathways, TGF-beta or BMPs, to prevent or avoid craniosynostosis or re-synostosis after a surgery.

Resumen: las suturas craneales son estructuras especializadas compuestas por el mesénquima sutural, el pericráneo suprayacente, la duramadre y los frentes osteogénicos. Cada una de estas estructuras expresan de forma diferencial, espacial y temporalmente, proteínas importantes para la maduración osteogénica, la osificación membranosa de los huesos calvarios y la homeostasis de las suturas craneales. Estas proteínas incluyen el factor de crecimiento fibroblástico (FGF) y sus receptores (FGFR), el factor de crecimiento transformante beta (TGF-beta), las proteínas morfogenéticas óseas (BMPs), así como factores de transcripción TWIST y MSX2, entre otros. La alteración en la expresión de una o varias de estas proteínas provoca múltiples condiciones patológicas, una de ellas es el cierre prematuro de una o varias suturas craneales, conocido como craneosinostosis. Esta malformación es comúnmente tratada con cirugía. Sin embargo, los avances en los campos de la biología molecular y celular han permitido investigar algunas proteínas que participan en el desarrollo de la craneosinostosis. Los resultados de estos estudios pueden generar futuras estrategias terapéuticas preventivas o que complementen los tratamientos quirúrgicos de la craneosinostosis. Algunas estrategias posibles son el uso de fármacos específicos que puedan regular la expresión y activación de las vías de señalización del FGF, el TGFbeta o de las BMPs, para prevenir la craneosinostosis o evitar la resinostosis tras una cirugía.