Evaluación in vitro de la filtración coronaria empleando dos materiales de obturación / Coronal microleakage of two temporaty reatorative materials. In vitro study provisoria

Objetivo: en este trabajo se comparó la filtración coronaria en cavidades de acceso irrigadas con soluciones empleadas solas y combinadas obturadas con ionómero vítreo con y sin acondicionamiento de la dentina y con guta plástica secando o lavando y secando las cavidades de acceso. Material y Métodos: Se emplearon 148 molares, se realizaron cavidades de acceso de 4 mm de profundidad. Se irrigaron con NaOCl 2% (n=24), CHX 2% (n=24), ETA 17% (n=24), NaOCl 2% + EDTA 17% (N=24), NaOCl 2% + CH 2% (n=24), EDTA 17% + CHX 2% (n=24). 2 piezas se prepararon como control positivo y 2 como control negativo. Luego de irrigadas 72 cavidades de acceso se obturaron con guta plástica (Provis. Favodent, Germany) y 72 se obturaron con ionómero vítreo (Riva, SDI, Australia). Dentro de las obturadas con guta plástica la mitad de las cavidades de acceso sólo se secaron, la otra mitad se lavaron para eliminar el irrigante y luego se secaron previo a la colocación del material. La que se obturaron con ionómero vítreo, la mitad sólo se secaron y en la otra mitad de las piezas se acondicionó la dentina conácido poliacrílico al 11,5% DLF (Brasil), durante 1 minuto, luego se lavaron con spray de agua y secaron, previo a la colocación del material. Posteriormente se realizó el termociclado (300 ciclos), sumergiendo las piezas dentarias en baños de Fucsina Básica a 5ºC y 55ºC (±2). Se penetración del colorante en milímetros. Los datos fueron analizados estadísticamente. Resultados: La filtración coronaria fue significativamente menor al emplear guta plástica test t (p<0,0001). Al comparar la filtración del ionómero con y sin acondicionamiento de superficie, hubo menor filtración cuando se trató la dentina Test Mann-Whitney (p<0,0001). Al comparar la filtración cuando se empleó guta plástica en cavidades secadas, con las que fueron lavadas y secadas, no se observaron diferencias significativas Test Mann-Whitney (p=0,075). Conclusiones: La menor filtración se observó al emplear guta plástica. Dentro del grupo obturado con ionómero vítreo, la filtración fue menor al acondicionar la dentina. Parcialmente subsidiado por el CIUNT (AU)

Aim: The purpose of this in vitro study was to compare the coronal microleakage with the glass ionomer with and without dentin conditioning and cavit dried and the other half rinsed and dried. Material and Methods: 138 human molars were used. Coronal access to the pulp chambers was prepard by using diamond burns. Final access cavities of approximately 4 mm were standardized. After rising for 10 min. with 2% NaOCl (n=24), 2% CHX (n=24), 17% EDTA (n=24), 2% NAOCl + 17% EDTA were filled with glass ionomer proceeding in two ays: the middle pieces of group were dried and the other half were conditioned with polyacrylic acid, rinsed and dried. The another group were filled with cavit, the middle pieces of group were dried and the other half were rinsed and dried. The tooth surfaces were covered with nail varnish, the access were left unfilled. After 48 h. the specimes were thermocycled for 200 cycles in Basic Fucsina at 5ºC and 55ºC with a dwell time 30 s, in each bath. After the teeth were longitudinally sectioned in a bucolingual direction using diamond burn. The accesses were observed in binocular microscope and dye penetration was measure. Data were analyzed statistically. Results: Coronal microleakage was significantly lower with cavit test (p<0,001). Cavit showed no differences in cavities dried and washed and dried by Mann-Whitney Test (p=0,075). Conclusions: The lowest microleakage was observed with cavit. With glass ionomer, the lower microleakage was glass ionomer using diamond burn. The accesses were observed in binocular microscope and dye penetration was measured. Date were analyzed statistically. Results: Coronal microleakage was significantly lower with cavit t test (p<0,0001). Cavit showed no differences in cavities dried and washed and dried by Mann-Whitney Test (p=0,075). Conclusions: The lowest microleakage was observed with cavit. With glass ionomer, the lower microleakage was glass ionomer using dentin conditioning. Partially subsidized by CIUNT (AU)

Efecto de soluciones de irrigación y sus combinaciones sobre la microdureza de la dentina radicular / Effects of irrigation solutions and their combinations on the microhardness of root canal dentin

Objetivo: en este trabajo se comparó la microdureza de la dentina radicular antes y después de la irrigación con soluciones empleadas solas y combinadas. Material y métodos: 35 dientes humanos anterosuperiores fueron instrumentados, sus raíces fueron cortadas en tercios, incluidas individualmente en resina acrílica y pulidas. Las piezas fueron divididas al azar en grupos de 5 raíces cada uno. Se pusieron en contacto durante 15 minutos con las siguientes soluciones: grupo1: EDTA 17%, grupo 2: hipoclorito de sodio (NaOCI) 1%, grupo 2: gluconato de clorhexidina (CHX) 05%, grupo 4: solución fisiológica, grupo 5: NaOCl 1% + EDTA 17%, grupo 6: NaOCl 1% + CHX 0,5%, Grupo 7: EDTA 17% + CHX 0,5%. La microdureza Vickers fue medida inicialmente y post irrigación a 0,5mm y 1mm, del conducto radicular, empleando 300 g, durante 15 segundos. Resultados: Mediante Variancia de tres vías con medidas repetidas en dos factores y comparaciones múltiples con ajuste de Bonferroni, se observaron diferencias significtativas (p<0,05) en la reducción de la microdureza al emplear EDTA 17% + NaOCl 1%, EDTA 17% + CHX 0,5% en los tercios apical, medio y cervical y con NAOCl 1% en los tercios medio y cervical. Conclusiones: EDTA 17% y sus combinaciones fueron más efectivas en reducir la microdureza dentinaria (AU)

Objective: The purpose of this study was to compare the root dentin microhardness before and after irrigation with alone and combined solutions. Material and Methods: Thirty-five human maxillary anterior teeth were used in this study. The crowns were removed at the cement-enamel junction, the root canals were enlarged. Each root was transversally sectioned into cervical, middle and apical segments and were mounted in an individual silicon device with acrylic resin. The dentin surface was polished. Prior to application of thest solutions, the Vicker´s hardness values of the specimens were measures. The roots were irrigated: group 1 (n=5) EDTA 17% Ç(n=5), group 2: sodium hypochlorite (NaOCl) 1% (n=5), group 3: chlorhexidine gluconate (CHX) 0,5% (n=5) group 4: saline solution (n=5) group 5: NaOCl 1% + EDTA 17% (n=5), group 6: NaOCl 1% + CHX 0,5% (n=5), group 7; EDTA 17% + CHX 0,5% (n=5). Microhardness measurements were performed on each section at 0,5 mm, and 1mm, from the pulp-dentin interface using 300 g. load perpendicular to the surface for 15 seconds. Results: With three-way Variance with repeated measures on two factors and multiple comparisons Bonferroni, significant differences (p<0,05) in the reduction of microhardness when using 17% EDTA, 17% EDTA + 1% NAOCl, EDTA 17% + CHX 0,5% in the apical, middle and cervical thirds and 1% NaOCl in the cervical and middle thirds. Conclusions: EDTA 17% and theis combinations were more effective than other solutions in microhardness reduction (AU)

Pastas de hidróxido de calcio preparadas con diferente soluciones. Acción solvente / Calcium hydroxide pastes mixed with different wehicles. Solvent action

Una de las sustancias más utlizadas para la desinfección de los conductos radiculares es el hidróxido de calcio. Es un polvo fuertemente alcalino que puede ser mezclado con difrentes vehículos y usado como pasta de obturación intermedia. Se han propuesto diferentes vehículos para formar la pasta de hidróxido de calcio, tales como agua destilada, solución fisiológica, anestesia, propilenglicol, paramonoclorofenol alcanforado entre otros. Estudios recientes han sugerido combinar el polvo del Ca (OH)2 con soluciones de irrigación par amejorar su acción solvente sobre el tejido pulpar y antibacteriana especialmente frete al E. faecalis y Candida albicans que mosraron ser resistentes a las pastas tradicionales. Objetivo: En este trabajo se comparó la acción solvente sobre el tejido pulpar bovino de diferentes pasats de hidroxido de calcio. Material y Métodos: Se usarón pulpas bovinas extraídas de animales jóvenes sobre las que se evaluó la acción de pastas de hidróxido de calcio con hipoclorito de sodio 1% hidróxido de calcio con gluconato de clorhexidina 1%, hidróxido de calcio con solución fisiológica, hasta 21 días. Se evaluó la capacidad de disulación del del tejido pulpar de estas pastas, usando como teztigo los vehículo mendionados. Los datos se analizaron estadísticamente con el test de Kruskal Wallis. Resultados y Conclusiones: Las tres pastas de hidróxdo de calcio se comportaron en forma semejante, con respecto a su acción solvente (AU)

Calcium hydroxide is frequently used as an atiseptic agent of root canals. It is ana alcaline powder and can be mixed with differente vehices to be used as an ntracanal medication. Astes can be developed using distilled water, CI NA 0,7% solution, anesthetics solutions, propylene glycol, camphorated paramonochloreophenol among others. Recent studies suggest using Ca (OH)2 with irrigating solutions to get a paste with better sovent and antibacerial action on pulpar tissue, specially against E. faecalis and Candida albicans. Objective: Comparison of solvent action of different calcium fydroxide pastes on bovine pulpar tissue is the main objectie of our study. Materials and Method.: We have used young boine pulpes and pastes of Ca (OH)2 with 1% sodium hypochlorite, with 1% chlorhexidine gluconate, with 0,7% Cl Na during 21 days. We evaluted disolution o pulpar tissue and each vhicle was our control group. Data was statisically analized using Kruskal Wallis test. Results and concluissions: All three calcium hdroxide pastes had similar solvent action (AU)

Efficacy of two techniques for endodontic instrumentation.

The aim of the present study was to compare the quality of preparation in curved and straight root canals employing 2 techniques, i.e. the step-back technique and the technique of Goerig, Michelich and Schultz. One hundred and thirty single-rooted human teeth were employed throughout. The walls of the root canals of these teeth were painted. Following instrumentation the roots were sectioned longitudinally. The sections were observed under a stereoscopic microscope SZ40 with a grid fitted in the eyepiece. The efficacy of instrumentation was evaluated using area of paint removed as the end-point. Statistical significance of the data was tested with the chi square test employing the Epi Info 5 software. There was no statistically significant difference between techniques for straight canals. The technique of Goerig, Michelich and Schultz was more effective than the step-back technique in the apical third of curved canals.

Efficacy of two techniques for endodontic instrumentation.

The aim of the present study was to compare the quality of preparation in curved and straight root canals employing 2 techniques, i.e. the step-back technique and the technique of Goerig, Michelich and Schultz. One hundred and thirty single-rooted human teeth were employed throughout. The walls of the root canals of these teeth were painted. Following instrumentation the roots were sectioned longitudinally. The sections were observed under a stereoscopic microscope SZ40 with a grid fitted in the eyepiece. The efficacy of instrumentation was evaluated using area of paint removed as the end-point. Statistical significance of the data was tested with the chi square test employing the Epi Info 5 software. There was no statistically significant difference between techniques for straight canals. The technique of Goerig, Michelich and Schultz was more effective than the step-back technique in the apical third of curved canals.

Efficacy of two techniques for endodontic instrumentation

The aim of the present study was to compare the quality of preparation in curved and straight root canals employing 2 techniques, i.e. the step-back technique and the technique of Goerig, Michelich and Schultz. One hundred and thirty single-rooted human teeth were employed throughout. The walls of the root canals of these teeth were painted. Following instrumentation the roots were sectioned longitudinally. The sections were observed under a stereoscopic microscope SZ40 with a grid fitted in the eyepiece. The efficacy of instrumentation was evaluated using area of paint removed as the end-point. Statistical significance of the data was tested with the chi square test employing the Epi Info 5 software. There was no statistically significant difference between techniques for straight canals. The technique of Goerig, Michelich and Schultz was more effective than the step-back technique in the apical third of curved canals.