Sustained increase of Ca+2 oscillations after chronic TRPV1 receptor activation with capsaicin in cultured spinal neurons.

Hyperalgesia and allodynia occur as a consequence of peripheral and central sensitization that follows sustained nociceptive activation. The cellular alterations associated to this state of nociceptive network hyperexcitability represent a form of neuronal plasticity, but they are not well understood because of its complexity in situ. In this study, after treating primary spinal neuron cultures with capsaicin (0.5-1 microM) for 48 h fluorimetric recordings were performed. The activation of TRPV1 receptors with capsaicin (0.5-1.0 microM) increased the frequency of calcium transients (0.03+/-0.002 Hz vs. 0.05+/-0.006 Hz, P<0.05), mediated by AMPAergic transmission, as well as the percent of neurons with activity (37+/-3% vs. 65+/-4%, P<0.05). The effect of capsaicin was long lasting and the neurons were found to be hyperfunctional and with increased levels of phosphorylated CREB (cAMP responsive element binding) even after 72 h of treatment with capsaicin (32+/-5% vs. 52+/-5%). The effect of capsaicin was blocked by capsazepine (1 microM), TTX (100 nM) and KN-62 (1 microM), but not by K252a (200 nM) or PD98059 (50 microM) indicating the involvement of TRPV1. The results suggest the participation of Ca2+, CaMKII and CREB on the prolonged enhancement of excitability following chronic exposure to capsaicin. Thus, it is likely that chronic TRPV1 activation is capable of inducing prolonged increases in neurotransmission mediated by glutamatergic receptors.

Bacterial microleakage at the abutment-implant interface, in vitro study.

INTRODUCTION: In implant rehabilitation, a microspace is created at the abutment-implant interface (AII). Previous research has shown that oral microbiome can proliferate in this microspace and affect periimplant tissues, causing inflammation in peri-implant tissues. Preventing microbial leakages through the AII is therefore an important goal in implantology. OBJECTIVE: To determine the presence of marginal bacterial microleakage at the AII according to the torque applied to the prosthetic implant in vitro. MATERIAL AND METHODS: Twenty-five Ticare Inhex internal conical implants (MG Mozo-Grau, Valladolid, España) were connected to a prosthetic abutment using torques of <10, 10, 20, 30, and 30 N and then sealed. The samples were submitted to cycles of occlusal loads and thermocycling, then one sample of each group was observed by micro TC, while the rest were mounted on devices according to the bacterial leakage model with Porphyromonas gingivalis. RESULTS: Bacterial leakage was observed only in the <10 and 10 N torque samples, and the same groups presented poor abutment/implant adjustment as determined by micro-CT. CONCLUSION: The different torques applied to the abutment-implant system condition the bacterial leakage at the implant interface. No microleakage was observed at 20 and 30 N.

Criterios de selección de marca comercial de implantes dentales más usados por especialistas / Brand selection criteria for specialists most used dental implants

RESUMEN: Objetivo: Determinar los criterios de selección más usados al elegir una marca comercial de implantes dentales según odontólogos especialistas. Material y método: Se identificaron los parámetros para escoger una marca de implantes, estos se clasificaron en técnicos y mercadológicos, ordenándose en un cuestionario de tipo cerrado, valorándose por medio de escala psicométrica Likert del 1 al 5, además se incluyó una pregunta abierta. Se tomó una muestra por conveniencia de veinte odontólogos especialistas con experiencia al menos en tres marcas de implantes. Para el análisis estadístico descriptivo se usó Microsoft Excel 2011 versión para Mac, utilizando medidas de tendencia central como la Media Aritmética y Moda. Los parámetros técnicos se clasificaron de 1a hasta 1i, mercadológicos del 2a hasta el 2f y los sugeridos de p1 a p7. Resultados: La variabilidad en pilares de retención protésica, disponibilidad adecuada de los productos ofertados por la empresa y la compatibilidad de los aditamentos entre marcas comerciales, fueron los factores más relevantes considerados por especialistas a la hora de elegir un determinado sistema de implante. Conclusión: Las razones que más influyen en la elección de un sistema de implante son la variedad y disponibilidad de productos junto a la compatibilidad entre marcas.

ABSTRACT: Objective: The aim of this study is to determine the most used selection criteria when choosing a commercial brand of dental implant according to specialist. Material and methods: We identified the parameters to choose an implant brand, these were classified as technical and marketing, ordered in a closed questionnaire, assessed by means of a Likert psychometric scale from 1 to 5, plus an open question was included. A convenience sample of twenty specialists with experience in at least three implant brands. For the descriptive statistical analysis, Microsoft Excel 2011 version for Mac was used, using measures of central tendency such as Arithmetic Media and Fashion. For this same purpose, the technical parameters were classified from 1a to 1i, marketing parameters from 2a to 2f and suggested parameters from p1 to p7. Results: The variability in prosthetic retention pillars, adequate availability of the products offered by the company and the compatibility of the abutments between trademarks, were the most relevant factors considered by specialists when choosing a specific implant system. Conclusion: The arguments that most influence the choice of an implant system are variety and availability of products, as well as the compatibility between brands.

Efecto del consumo de anticonceptivos orales en el flujo salival no estimulado, PH y capacidad buffer / Effect of oral contraceptive use in unstimulated salivary flow, pH and buffer capacity

La saliva, un elemento esencial en la preservación de salud oral, puede verse alterada por diversos factores, como el consumo de fármacos, en cuanto al flujo, pH o capacidad buffer, constituyendo un factor predisponente a diversas patologías (1). Comparar el flujo salival no estimulado, pH y capacidad buffer entre consumidoras y no consumidoras de anticonceptivos orales combinados. Cincuenta y seis mujeres sanas, entre 21 y 26 años de edad, con bajo riesgo cariogénico, dividida en dos grupos, consumidoras y no consumidoras de anticonceptivos orales. Para determinar el flujo salival no estimulado, se tomó una muestra de saliva durante 15 minutos. Para determinar los pH se utilizó un potenciómetro (PL-600Lab PH meter) y para determinar capacidad buffer se utilizó el método de Ericsson. Para analizar la significancia estadística de las diferentes pruebas se realizó la prueba U Mann-Whitney utilizando el software SPSS versión 14.0. El promedio de flujo salival no estimulado observado en este estudio, es mayor entre consumidoras de anticonceptivos orales, con un p<0.005. En cuanto a capacidad buffer, se obtuvieron valores levemente superiores en el grupo consumidor, mientras que los valores de pH resultaron similares entre ambos grupos. El flujo salival no estimulado se ve aumentado en las consumidoras de anticonceptivos orales combinados, mientras que la capacidad buffer presenta un incremento no significativo, mientras que el pH salival arroja valores similares para ambos grupos

Saliva is an essential element in oral health preservation and its pH, buffer capacity and flow rate, have a fundamental role. These factors may be altered by, among others, drug consumption which predisposes to several diseases (1). To compare the non-stimulated salivary flow rate, pH and buffer capacity between patients under Oral contraceptives medication and not taking any medication. Fifty six healthy women, aged 21 to 26 years, with low cariogenic risk, divided into two groups: under oral contraceptives medication and without medication. To determine the non-stimulated salivary flow rate, was taken a saliva sample during 15 minutes. To determine the pH, was used a potentiometer (PL 600Lab PH-meter) and buffer capacity was measured by Ericsson's method. Mann-Whitney test was performed using SPSS software version 14.0 to determine statistical significance. Mean of stimulated salivary flow rate is not statistically significantly in subjects under oral contraceptives medication (p <0.005). Buffer capacity showed slightly higher values in study group, while the pH values were similar in study and control groups. The stimulated salivary flow rate is not increased by consuming the Oral contracetives, the salivary pH shown similar values for both groups, and finally, the salivary buffer capacity, shown increased in the consumer group, however, it does not statistically significant