Agua y Suero Fisiológico para Prevenir la Formación de Paracloroanilina

Indexación: Web of Science; Scielo.ABSTRACT: This study determined if p-chloroaniline (PCA) can be minimized by using distilled water and physiological saline solution following sodium hypochlorite but before chlorhexidine. Hypochlorite 5%, 0.5%, 0.05%, 0.005% and 0.0005% dissolved in 0.9% NaCl and in distilled water were mixed with 2% chlorhexidine for the formation of PCA. The PCA was determined using UV-VISIBLE spectrometry, with spectral curve was determined the wavelength of maximum absorption of PCA. Formed PCA absorbance was measured between 0.025%, 0.02%, 0.015%, 0.01%, 0.005% and 0.0025% hypochlorite and 2% chlorhexidine. 2% chlorhexidine and hypochlorite with physiological saline form a white precipitate which prevents the measurement of PCA. Colored PCA is formed with 0.05%, 0.005% hypochlorite aqueous dilutions and 2% chlorhexidine. The lwavelength of maximum absorption obtained was 470 nm and absorbance of PCA showed a linear decrease. 0.005% NaClO produces the least amount of PCA. The best solvent to prevent the formation of PCA during the interaction of sodium hypochlorite with chlorhexidine is distilled water.Este estudio determinó si la p-cloroanilina (PCA) puede ser minimizada mediante el uso de agua destilada y solución salina fisiológica seguido de la aplicación de hipoclorito de sodio, previo a la aplicación de clorhexidina. Hipoclorito al 5%, 0,5%, 0,05%, 0,005% y 0,0005% fue disuelto en 0,9% de NaCl y en agua destilada se mezcló con 2% de clorhexidina para la formación de PCA. El PCA se determinó mediante espectrometría UV-Visible, y con curva espectral se determinó la longitud de onda máxima del PCA. La absorbancia del PCA formado se midió con 0,025%, 0,02%, 0,015%, 0,01%, 0,005% y 0,0025% de hipoclorito y 2% de clorhexidina. La combinación de 2% de clorhexidina e hipoclorito en solución salina fisiológica forman un precipitado blanco que impide la medición del PCA. El PCA coloreado es formado con 0,05%, 0,005% diluciones acuosas de hipoclorito y 2% de clorhexidina. La longitud de onda máxima obtenida fue de 470 nm y la absorbancia del PCA mostró una disminución lineal. NaClO al 0,005% produce menor cantidad de PCA. El mejor disolvente para evitar la formación de PCA durante la interacción de hipoclorito de sodio con clorhexidina es agua destilada.http://ref.scielo.org/2kpw6

Effect of endodontic ultrasound on 2% chlorhexidine in the formation of parachloraniline. In vitro study

Resumen Introducción: La clorhexidina (CHX) en solución acuosa se hidroliza generando paracloroanilina (PCA), proceso acelerado por el aumento de temperatura y pH. El uso de ultrasonido endodóntico (USE), basado en fenómenos de oscilación, cavitación, microcorriente acústica, genera calor afectando la CHX. Objetivo: Identificar y cuantificar in vitro cambios fisicoquímicos, temperatura y pH, y la cantidad de PCA formada con el uso de ultrasonido endodóntico sobre soluciones de CHX al 2%. Materiales y métodos: La CHX 2% se activó durante 30, 60, 90 y 120 seg con USE a 24.500 Hz, midiendo antes y después de activación: pH, temperatura y cantidad de PCA, leyendo a 375 nm en curva de calibración de estándares de PCA y formación, registrando el espectro de absorción mediante espectrofotómetro UV-visible. Resultados: El USE aumentó la temperatura en 1 ◦C independiente del tiempo de aplicación y acidificó la solución de CHX 2%, sin variaciones significativas en pH y temperatura. No se observó coloración ni formación de precipitado en muestras activadas por USE a los diferentes tiempos. Las muestras no presentaron valores medibles de PCA a 375 nm. Los espectros de absorción de CHX 2% y activadas por USE por más de 60 seg presentaron curvas espectrales, peaks y valores de absorbancia diferentes

Development of a research and innovation network on Fluoride and dental Fluorosis in latin america: Desenvolvimento da rede de pesquisa e inovação em Flúor e Fluorose dentária na américa latina

Dental Fluorosis is a growing public health problem in many parts of the world. Dental Fluorosis in the world youngster population is increasing, as it is highlighted in the latest Latin American epidemiological report. There are few   studies on fluorosis and its prevalence in the region.  These are the basis for the creation of this international network, including Chile, Colombia, Ecuador, Paraguay and Argentina. In these countries there has been a significant increase in Dental Fluorosis, with values between 50% and 60%. A central goal of this network is to understand the “production-consumption source”, environment and the monitoring of systemic fluoride exposure, key to promote the benefits of fluorides and minimize the risks of chronic overexposure, leading to fluorosis. The significant increase in fluorosis in the Latin American region led to the formation of this research network. Its aim is to create a network of research centers in Latin America based on the management of spaces for communication, exchange and generation of knowledge on the subject of fluorides and dental fluorosis, and to generate products that can be used as inputs for public policy in the national health systems of the countries

Effects of chlorophenol / hydrogen peroxide versus xylitol or chlorhexidine as chewing gum on salivary flow rate, pH, buffer capacity and salivary Streptococcus mutans scores

Objectives: A medicated chewing gum is a solid, single-dose preparation intended to be chewed for a certain period of time and deliver the drug. It may contain one or more than one active pharmaceutical ingredient. Whithin this context, we formulated a medicated gum with three active pharmaceutical ingredients: Camphor, p-chlorophenol and hydrogen peroxide, to be evaluated as therapeutic agents in dental caries. The aim of this study was to compare the effects on salivary streptococcus mutans, pH, buffer capacity and secretion rate of three medicated gums containing chlorophenol / hydrogen peroxide, xylitol or chlorhexidine. Methods: Double-blind, randomized crossover treatment in 24 subjects. The patients were randomized and subjected to six different treatment sequences. The subjects used, 1 gum tablet three times a day for 20 minutes, morning, noon and night. At the beginning and end of the three experimental phases saliva samples were obtained for determining the pH, buffer capacity, salivary flow rate and quantitative enumeration of S. mutans. Results: The use of medicated gum with camphor/p-chlorophenol and hydrogen peroxide did not modify the salivary chemical parameters measured, and not significantly reduced the number of S. mutans, after 7 days. Chewing gums with chlorhexidine significantly reduced the quantitative counting of S. mutans salivary and flow rate in a period of 7 days. Conclusions: The use of medicated chewing gums based on camphor/p-chlorophenol and hydrogen peroxide does not alter the chemical salivary parameters and does not significantly reduce the number of S. mutans, after a use over a period of 7 days

Caries and fluorosis in the Santiago metropolitan region in Chile: The impact of the fluoridation of the water

Purpose: To assess the damage and the prevalence of caries and fluorosis in children and adolescents in the metropolitan area after 8 years of drinking water fluoridation and to compare them with the baseline study. Methods: This was a prevalence study. The sample was selected using two-step probability sampling and stratified according to socioeconomic level. Subjects included 2,323 schoolchildren aged 6 to 8 years and 12 years living within the metropolitan region. The parents of all students provided consent and were previously included in the study. The subjects were clinically examined by calibrated dentists, who used World Health Organization (WHO) screening criteria and indicators to determine the presence of caries and dental fluorosis. Results: No cavity damage was found in 23.68% of the children. The average dmft was 3.18 for children aged 6 to 8 years. The DMFT was 0.59 in children aged 6 to 8 years and 2.6 in children 12 years compared with the baseline study. These differences were statistically significant. There were also significant differences in the DMFT index for each socioeconomic status group. The average number of dams was higher among children of low socioeconomic status. Of the studied children, 14.3% of children had dental fluorosis. Fluorosis was very mild in 12.35% of the cases, mild in 1.98% and moderate in 0.26%. There were no cases of severe fluorosis (classified according to Dean’s index). Conclusion: We conclude that after 8 years drinking water fluoridation in the metropolitan area, the number of children with no history of caries has increased by approximately 100%. The number of cases significantly affected by caries has also decreased significantly. The incidence of dental fluorosis has increased, but to milder degrees