Assessment of Drying Protocol on the Bond Strength and Tag Penetration of Two Different Sealers to the Root Dentin: An In Vitro Study.

Accomplishment of an ideal root canal treatment is attributed to various essential factors such as proper instrumentation, chemomechanical preparation, obturation and post endodontic restoration. The main aim of this study is to test the null hypothesis that is the moisture condition of root dentin would not affect the bond strength and sealer penetration. This is an in vitro study conducted in Department of Conservative Dentistry and Endodontics, M A Rangoonwala Dental College, Pune, India over a period of two years (from 2021 to 2023). One hundred and twenty single-rooted Premolars with fully formed apices and similar root morphology were obtained and stored in 0.1% thymol solution. The specimens were randomly assigned to 3 broad experimental groups (n=40) according to the drying protocol such as Group A- Paper points (P), Group B- diode laser (L) and Group C- isopropyl alcohol (A). For each drying protocol, the specimens were further assigned to 2 subgroups (n=20) with respect to the sealers used: AH Plus (AH) and Apexit Plus sealers (APx). The effect of drying protocol using paper points, isopropyl alcohol and diode-lasers on the bond strength and tag penetration of two different sealers to the root dentin was evaluated. Maximum overall push-out Bond strength was seen in group AH+L and least in group APx+ L. Inter-site push-out bond Strength was highest in the coronal third followed by the middle and least in the apical third of all the groups. Maximum over all depth of penetration was seen in group AH+L and minimum in group APx+L. AH plus sealer showed better bond strength, sealer penetration and adaptation to the dentinal walls compared to Apexit plus sealer, irrespective of the drying protocol followed. All the drying protocols used did not show statistically significant results in the apical thirds of root canals of all the groups.

Decoloración coronaria inducida por la utilización de Biodentine y MTA blanco en procedimientos de regeneración pulpar: estudio ex vivo / Coronal discoloration induced by the use of Biodentine and white MTA in pulp regeneration procedures: an ex-vivo study

Se comparó el grado de decoloración de la corona clínica en piezas dentarias anteriores humanas ex-traídas, sometidas a procedimientos de regeneración endodóntica, utilizando MTA blanco o sustituto bioac-tivo de la dentina (Biodentine) como barrera cervical, en presencia de coágulo sanguíneo como andamio. En total se prepararon 24 piezas dentarias anterio-res superiores humanas que fueron divididas en dos grupos control (GC) y dos grupos experimentales (GE). Cada uno incluía 6 piezas dentarias. En los GE se colo-có sangre humana fresca en el interior del conducto, y se confeccionó una barrera de Biodentine (GE3) o MTA (GE4). En los GC se colocó una torunda de algo-dón estéril saturada con solución fisiológica estéril, y se confeccionó una barrera de Biodentine (GC1) o MTA (GC2). El color se evaluó de acuerdo con el espa-cio de color CIE L* a* b* utilizando imágenes fotográfi-cas digitales estandarizadas en dos puntos de tiempo: día 0 (T0) y día 35 (T35). La descripción de los datos in-cluyó mediana (Md), primer cuartil (Q1), tercer cuartil (Q3), media y desviación estándar (DE). Se emplea-ron las pruebas de los rangos con signo de Wilcoxon (RSW) y ANOVA de una vía; p < 0,05 fue considerado significativo. Cuando se comparó ∆E se observaron diferencias significativas entre GC1 y el resto de los materiales (p < 0,05). ∆E fue menor en GC1 (media ± DE; 2,1 ± 1,6) que en los grupos restantes que no pre-sentaron diferencias significativas entre sí. En base a estos resultados, la estabilización del coágulo san-guíneo, como así la limpieza de la cavidad previa a la colocación del Biodentine y el uso de barreras cervi-cales, es imprescindible para evitar la coloración de la corona clínica (AU)

Discoloration remains an unfavorable complication of otherwise successful regenerative endodontic procedure of immature teeth with necrotic pulp. Objective: Compare the degree of discoloration of extracted human teeth after regenerative endodontic procedures, using MTA or Biodentine as a cervical barrier with a blood clot as a scaffold. In total 24 human upper anterior teeth were prepared and divided into two control groups (CG) and two experimental groups (EG). In the EG, fresh human blood was placed inside the root and a Biodentine (GE3) or MTA (GE4) barrier was made in. A sterile cotton swab saturated with sterile physiological solution was placed in the GCs and a Biodentine (GC1) or MTA (GC2) barrier was made in. The color was evaluated according to the CIE L* a* b* color space using standardized digital photographic images at two time points: day 0 (T0) and day 35 (T35). The description of the data included median (Md), first quartile (Q1), third quartile (Q3), means, and standard deviation (SD). Wilcoxon signed rank tests (RSW) and one-way ANOVA were used. p < 0.05 was considered significant. When ∆E was compared, significant differences were observed between GC1 and the rest of the materials (p < 0.05). ∆E was lower in CG1 (mean ± SD; 2.1 ± 1.6) than in the remaining groups, which did not present significant differences between them. There was no significant difference between tooth discolorations with materials in the presence of blood. However, in the absence of blood, Biodentine exhibited less tooth discoloration than MTA (AU)

Comparison of Fracture Resistance of Endodontically Treated Teeth Restored with FiberSite Postsystem and Glass Fiber, Combined with Different Root Canal Sealers.

This study is aimed at evaluating the effects of FiberSite and glass fiber postsystems on the fracture resistance of endodontically restored teeth, when combined with various root canal sealers. Forty human mandibular premolar teeth, each having a single root with anatomically comparable dimension and length, were selected. The teeth in each experimental group (n = 10) were instrumented, obturated, and restored with the following procedures: in group 1, AH Plus root canal sealer and a glass fiber post with a composite core; in group 2, AH Plus root canal sealer and a FiberSite postsystem; in group 3, Sure-Seal Root canal sealer and a glass fiber post with a composite core; and in group 4, Sure-Seal Root canal sealer and a FiberSite postsystem. The specimens were placed on a universal test machine. The fracture resistance of all specimens was tested using generic test equipment, and the value of the force in newton (N) during fracture was measured for each root. A statistical analysis was conducted through the Kruskal-Wallis test as well as the post hoc test. The tests showed a significant difference between groups 2 and 3, with group 3 producing load values that were significantly higher than group 2. In contrast, no significant differences were found to exist between the other groups. Regardless of postsystems, groups 3 and 4 showed higher mean fracture values (but no statistically significant differences) than groups 1 and 2.

Intratubular penetration of endodontic sealers depends on the fluorophore used for CLSM assessment.

Root canal filling aims at eliminating empty spaces into the root canal system using biologically compatible materials. Three-dimensional root canal obturation must prevent or minimize the reinfection caused by microorganisms' leakage. This study aimed at evaluating whether fluorophore (Rhodamine or Fluo-3) influences the CLSM images of intratubular penetration of four endodontic sealers. Eighty bovine teeth were prepared using K files up to a size #70 and irrigated with 2.5% sodium hypochlorite. All roots were divided into eight groups (n = 10) according to the sealer and fluorophore used: AH Plus/Rhodamine, AH Plus/Fluo-3, Sealer Plus/Rhodamine, Sealer Plus/Fluo-3, Sealer Plus BC/Rhodamine, Sealer Plus BC/Fluo-3, Endosequence/Rhodamine, and Endosequence/Fluo-3. All roots were filled using cold lateral compaction technique. After 7 days, the roots were transversely sectioned, and three slices, one of each canal third, were obtained. Intratubular penetration was evaluated using CLSM. Sealer Plus BC/Rhodamine and Endosequence BC/Rhodamine presented higher intratubular penetration than AH Plus/Fluo-3 and Sealer Plus/Fluo-3 (p ˂ .05). The intragroup analysis showed similar intratubular penetration, regardless of the root third, except for the apical third in AH Plus/Fluo-3 and Sealer Plus BC/Fluo-3 groups. The type of fluorophore influences the calcium silicate sealers' tubular penetration but not of epoxy resin-based ones using CLSM. Bioceramic sealers should not be used associated with Rhodamine for CLSM evaluation. RESEARCH HIGHLIGHTS: The type of fluorophore influences the calcium silicate sealers' tubular penetration but not of epoxy resin-based ones when CLSM is used for assessment. Bioceramic sealers should not be used associated with Rhodamine.

Remoción de hidróxido de calcio del canal radicular con irrigación manual, sónica y ultrasónica / Calcium hydroxide removal from the root canal by manual, sonic and ultrasonic irrigation

Introducción: Resulta fundamental la remoción por completo del hidróxido de calcio previo a la obturación del canal radicular que podría impedir la penetración de los selladores en los túbulos dentinarios. Objetivo: Determinar la efectividad de la eliminación de la medicación con hidróxido de calcio del canal radicular de dientes utilizando diferentes sistemas de irrigación. Métodos: Se irrigaron con hipoclorito de sodio 148 conductos radiculares rectos de dientes humanos. Se utilizó Ca(OH)2 mezclado con tinta negra para rellenar los canales radiculares y facilitar la visualización. Los dientes se dividieron en 5 grupos de acuerdo al protocolo de eliminación. En cada uno de los grupos, la extrusión apical se midió durante la etapa de irrigación por el método Huang X, después de la eliminación del Ca(OH)2, se seccionaron longitudinalmente y luego, en un portaobjetos, se observaron las muestras bajo un microscopio óptico. Finalmente, se analizó el contenido para cuantificar el grado de extrusión causado durante el procedimiento clínico. Se utilizó el test de ANOVA para el análisis estadístico Resultados: Se encontró diferencias significativas entre los grupos 1-2, 1-3, 1-4 y 1-5. El promedio de remanecía fue superior (66,4 por ciento). Los grupos 2 (41,6 por ciento) y 5 (34,8 por ciento) obtuvieron mayor eficacia en la remoción. ANOVA (α = 0,05) determina que no existieron diferencias significativas entre los 5 grupos. Conclusiones: Los dispositivos de activación ultrasónica mostraron una mayor eliminación de la medicación con hidróxido de calcio desde las paredes dentinarias a las técnicas manuales, sin embargo, demostró ser una terapia más invasiva debido a una mayor extrusión de detritus(AU)

Introduction: Root canal sealing should indispensably be preceded by complete calcium hydroxide removal, otherwise the latter might prevent the penetration of the sealers into the dentinal tubules. Objective: Determine the effectiveness of eliminating calcium hydroxide medication from the root canal of teeth using various irrigation systems. Methods: Preparation was conducted of 148 straight root canals of human teeth irrigating with sodium hypochlorite. The root canals were filled with Ca(OH)2 mixed with black ink to facilitate visualization. The teeth were divided into 5 groups in compliance with the removal protocol. Apical extrusion was measured in each group during the irrigation stage using the Huang X method. After Ca(OH)2 removal they were sectioned longitudinally and placed on a slide for observation of the samples under an optical microscope. Finally the content was analyzed to quantify the degree of extrusion obtained during the clinical procedure. The ANOVA test was used for statistical analysis. Results: Significant differences were found between the groups 1-2, 1-3, 1-4 and 1-5. Average remanence was above 66.4 percent. Groups 2 (41.6 percent) and 5 (34.8 percent) displayed higher removal efficacy. ANOVA (α = 0.05) did not determine any significant differences between the 5 groups. Conclusions: Ultrasonic activation obtained greater calcium hydroxide removal from the dentinal walls than manual techniques. However, it proved to be a more invasive therapy due to the greater detritus extrusion(AU)

Disinfection and surface changes of gutta-percha cones after immersion in sodium hypochlorite solution containing surfactant.

In this study, we evaluated the effectiveness of 1 and 5.25% NaOCl solutions, with or without surfactant, in disinfecting gutta-percha cones. Surface changes of the gutta-percha cones after disinfection were also assessed under scanning electron microscopy (SEM). One-hundred and eight gutta-percha cones previously contaminated with Enterococcus faecalis were left in contact for 30 s or 1 min with the following solutions (n = 12): 1% NaOCl; 1% NaOCl + 2% cetrimide; 5.25% NaOCl; 5.25% NaOCl + 2% cetrimide. Positive control group was composed by the remaining contaminated cones (n = 12), and the negative control group by noncontaminated cones (n = 12). The cones were kept in Eppendorf tubes containing Trypticase Soy Broth at 37°C for 24 hr, and then, the presence of turbidity was analyzed. Ten additional cones (n = 2) were observed under SEM to evaluate surface changes after 1 min of disinfection. The data analysis (Kruskal-Wallis test, α = 5%) demonstrated that regardless the presence of surfactant, the NaOCl solutions used were effective in the disinfection when cones were immersed for 1 min. However, at the 30-s period, only the 5.25% NaOCl solution was effective. SEM analysis demonstrated that NaOCl solutions promoted the formation of sodium chloride crystals on cones surface, less visible when the 1% NaOCl associated to surfactant was used. The addition of surfactant did not affect the disinfection capacity of NaOCl solutions. However, the surfactant has apparently inhibited the sodium chloride crystals deposition on the cones surface when associated to 1% NaOCl solution.

Penetrability of a new endodontic sealer: A confocal laser scanning microscopy evaluation.

This study aimed to evaluate the penetration of a new endodontic sealer into the dentinal tubules. Twenty single-rooted teeth were selected. The crown was sectioned, and the canals were instrumented with a reciprocating system. Irrigation was performed with 2 mL of 2.5% sodium hypochlorite between each file change. After instrumentation, the root canals were irrigated with 2 mL of17% EDTA for 3 min followed by saline solution. The specimens were randomized into two groups (n =10) according to the endodontic sealer: AH Plus (AP) or Sealer Plus (SP). All specimens were filled using the lateral compaction technique. Rhodamine B dye (red) was incorporated to the sealers to provide the fluorescence which will enable confocal laser scanning microscopy (CLSM) assessment. The roots were sectioned 2, 4, and 6 mm from the apex and assessed by CLSM. The root canal level affected the penetration of the sealer, but no statistical significant differences were found between the two experimental groups (p > .05). SP presented similar dentinal penetration and perimeter integrity to the gold standard (AP). RESEARCH HIGHLIGHTS: Sealer Plus presents dentinal penetrability and perimeter integrity similar to the gold standard sealer (AH Plus), demonstrating excellent ability of filling areas of difficult access.

Evaluation of 17% EDTA and 10% citric acid in smear layer removal and tubular dentin sealer penetration.

The purpose of this study was to compare the efficacy of different chelating solutions (17% EDTA and 10% citric acid) on the smear layer removal, and their effect on tubular dentin sealer penetration. Sixty root canals were prepared and distributed into four groups (n = 15) according to the final irrigation protocol: G1, final irrigation with 2.5 mL of distilled water; G2, final irrigation with 2.5 mL of 2.5% sodium hypochlorite solution; G3, final irrigation with 2.5 mL of 17% EDTA; and G4, final irrigation with 2.5 mL of 10% citric acid. Five specimens from each group were not filled to assess smear layer removal by scanning electron microscopy. Ten specimens from each group were filled for analysis of sealer penetration into dentinal tubules by confocal laser scanning microscopy. Smear layer removal (Kruskal-Wallis and Dunn's tests) and sealer penetration (F and Tukey's tests) were statistically analyzed with 95% of significance level. G3 and G4 had greater smear layer removal rates in the cervical and middle thirds, in comparison with G1 and G2 (p < .05). G3 and G4 had the highest percentages of sealer penetration in all thirds, in comparison with G1 and G2 (p < .05). Smear layer removal was effective only at the cervical and middle thirds when the chelating solutions were used. Sealer penetration into the dentinal tubules significantly increased in all root thirds when the specimens were treated with both chelating solutions.

Análisis morfométrico de conos de gutapercha Mtwo / Morphometric analysis of Mtwo gutta-percha cones

Objetivo: Evaluar cuantitativamente el calibre y la conicidad de los conos de gutapercha Mtwo (VDW, Munich, Alemania). Materiales y métodos: se seleccionaron al azar 50 conos de gutapercha marca Mtwo (VDW, Munich, Alemania) entre 300, provenientes de 5 cajas de conos surtidos #25 .06, #30 .05, #35 .04, #40 .04 y #25 .07. Fueron descartados aquellos que visualmente tenían algún defecto. Los elegidos se separaron en grupos de 10, según el número. Se midió cada cono en el vértice y a 1 mm, 2 mm, 3 mm, 4 mm y 5 mm, con un especímetro centesimal modelo 7301 (Mitutoyo, Japón). Se realizaron 300 determinaciones, que fueron efectuadas por dos operadores. Cuando hubo diferencias, se repitieron las mediciones hasta hallar coincidencia. Los datos fueron registrados en una planilla de Excel (Microsoft Corporation, Estados Unidos) diseñada al efecto. El análisis estadístico se llevó a cabo con prueba de hipótesis de dos colas, contrastando la media con el valor teórico. Resultados: se hallaron diferencias estadísticamente significativas para los conos #25 .06, en la determinación a 2 mm. En cuanto al resto de las mediciones, no hubo diferencias significativas. Conclusión: de acuerdo a los resultados obtenidos sobre la muestra analizada, en general los conos de gutapercha Mtwo respetan las espcificaciones ISO de fabricación.

Pulpotomy Medicaments used in Deciduous Dentition: An Update.

The aim of this paper was to review the history and the scientific literature published on pulpotomy medicaments and to present the findings of these studies. The review showed that pulpotomy of primary teeth has been treated with many different techniques and medicaments, that some of these approaches are controversial and that their results have presented variables of success rates in term of clinical, radiographic and histologic observation. It is important that all clinicians, particularly for pediatric dentists, be up to date with the recent trends in this area of dental treatment for children.

The effect of blood contamination on dislocation resistance of different endodontic reparative materials.

This study evaluated the retention characteristics of ProRoot mineral trioxide aggregate (MTA), RetroMTA, Supra MTA, and Biodentine biomaterials used to repair furcation perforations contaminated with blood. Furcal perforations measuring 1.3 mm in diameter and 2 mm in height were created in 96 mandibular first molar teeth, which were then randomly divided into the following two groups (n = 48): contaminated (+) or non-contaminated (-) with blood. The groups were subdivided into four groups (n = 12) according to the material used (ProRoot MTA, RetroMTA, Supra MTA, and Biodentine) to seal the perforations. The samples were allowed to set for 14 days and were then subjected to push-out testing. The results were analyzed using ANOVA, and the failure modes were examined using a surgical microscope. ProRoot MTA (+/-) and RetroMTA (+/-) exhibited superior bond strength values; in addition, there were no significant differences among these groups (P > 0.05). Biodentine (+) showed intermediate values that were sometimes statistically similar to the ProRoot MTA (+/-) and RetroMTA (+/-) groups (P > 0.05) and, at other times, the Biodentine (-) and Supra MTA (+/-) groups (P > 0.05). The lowest bond strength values were shown by the Biodentine (-) and Supra MTA groups (P > 0.05). "Adhesive failure mode" was the most frequently observed type for all tested materials. Blood contamination did not affect the dislocation resistance of materials.

Cimento experimental bioativo à base de glicerol salicilato contendo α -fosfato tricálcico para uso endodôntico / Bioactive cement experimental glycerol based salicylate containing α tricalcium phosphate for endodontic use

O tratamento de canal ideal compreende a desinfecção e selamento do sistema de canais radiculares, de forma a impedir a reinfecção e permitir o reparo dos tecidos periapicais. Para isso é necessário o emprego de materiais que promovam um perfeito selamento, o que até o presente momento não foi completamente alcançado. O objetivo do presente estudo in vitro foi desenvolver um cimento endodôntico à base de resina de glicerol salicilato e α-fosfato tricálcico (αTCP), que apresente potencial de estimular a deposição mineral. Os cimentos foram formulados a partir de 70% em massa de uma resina de glicerol salicilato, obtida a partir da reação de transesterificação do salicilato de metila com o glicerol, e 30% em massa de carga inorgânica, composta de hidróxido de cálcio e αTCP, em diferentes proporções: 30% Ca(OH)2, 25% Ca(OH)2 + 5% αTCP, 20% Ca(OH)2 + 10% αTCP, 15% Ca(OH)2 + 15% αTCP. A resina sintetizada foi caracterizada por cromatografia de exclusão por tamanho, ressonância magnética de prótons e espectroscopia Raman. Os cimentos foram caracterizados quanto ao tempo de presa, degradação in vitro, potencial de alcalinização do meio, citotoxicidade e capacidade de estimular a deposição mineral. A resina de glicerol salicilato foi obtida por meio da reação de transesterificação, com 72% de rendimento. Os grupos avaliados apresentaram um tempo de presa de 240 min a 405 min e capacidade de alcalinizar o meio...

Dental root canal treatment comprises the disinfection and complete filling of root canals in order to prevent the reinfection and allows the healing of periapical tissues. The use of materials that promotes an effective sealing has no achieved at the moment. The aim of this in vitro study was to develop a root canal sealer based on a glycerol salicylate resin and α-tricalcium phosphate (αTCP) that presents potential to stimulate mineral deposition. Sealers were formulated based on 70wt% of a glycerol salicylate resin, obtained by transesterification of methyl salicylate and glycerol, and 30wt% of inorganic filler, composed by calcium hydroxide and αTCP, in different proportions: 30% Ca(OH)2, 25% Ca(OH)2 + 5% αTCP, 20% Ca(OH)2 + 10% αTCP, 15% Ca(OH)2 + 15% αTCP. Synthesized resin was characterized by proton nuclear magnetic resonance spectroscopy, size exclusion chromatography and Raman spectroscopy. Sealers were characterized based on setting time, in vitro degradation over time, pH, cytotoxicity and mineral deposition. The glycerol salicylate resin was obtained by transesterification reaction, with 72% yield. Sealers presented setting time ranging from 240 min to 405 min, and basic pH over 8.21 after 28 days. Higher αTCP concentration leads to sealers with low solubility. Cell viability after 48 h in direct contact with sealers was similar to a commercial sealer (AH Plus) used as reference...

Efecto de la humedad sobre el fraguado del MTA: estudio "in vitro" / The effect of moisture on the setting of MTA: an in vitro study

Objetivo: evaluar el efecto de la humedad sobre el fraguado del ProRoot MTA, en sus superficies intraconducto y apical. Materiales y métodos: se emplearon 20 probetas cilíndricas huecas, de silicona transparente, instaladas sobre un block de gomaespuma humedecido con suero fisiológico. Las probetas fueron obturadas con 4 mm de espesor de ProRoot MTA (Dentsply Tulsa Dental, OK, Estados Unidos) y divididas al azar en dos grupos de 10 probetas cada uno. En el grupo 1 se colocó sobre el material una torunda de algodón seco, mientras que en el grupo 2 el algodón estaba humedecido con agua destilada. Los orificios superiores de las probetas se obturaron con cemento de óxido de zinc reforzado Zoer´s (Laboratorio SL SA, Buenos Aires, Argentina). Los especímenes se mantuvieron a 37ºC de temperatura y 100% de humedad. A las 4 y 6 horas fueron removidos de la gomaespuma, se retiraron el Zoer´s y el algodón y se registró el fraguado en las superficies del MTA intraconducto -subgrupos 1A y 2A- y apical -subgrupos 1B y 2B-, empleando una aguja Gillmore. El procedimiento estadístico fue realizado mediante la prueba de Chi cuadrado. Resultados: a las 4 horas, se encontraba fraguado el 50 por ciento de las muestras del subgrupo 1A, el 80 por ciento de las del subgrupo 1B, el 90 por ciento de las del subgrupo 2A y el 100 por ciento de las del subgrupo 2B. A las 6 horas de control, todas las muestras se encontraban fraguadas (100 por ciento). Se registraron diferencias estadísticamente significativas -a las 4 horas- entre los subgrupos 1A y 2A (P<0,05); entre los subgrupos 1ºB y 2B no las hubo (P>0,05). Tampoco hubo diferencias estadísticamente significativas entre los subgrupos 1A y 1B ni entre los subgrupos 2A y 2B (P>0,05). Conclusión: la presencia de un algodón húmedo en contacto con el MTA acelera el fraguado de la superficie intraconducto del material, en tanto no influye en el fraguado de su superficie apical

Application of microcomputed tomography for quantitative analysis of dental root canal obturations.

INTRODUCTION: The aim of the study was to apply microcomputed tomography to quantitative evaluation of voids and to test any specific location of voids in tooth's root canal obturations. MATERIALS AND METHODS: Twenty root canals were prepared and obturated with gutta-percha and Tubli-Seal sealer using the thermoplastic compaction method (System B+Obtura II). Roots were scanned and three-dimensional visualization was obtained. The volume and Feret's diameter of I-voids (at the filling/dentine interface) and S-voids (surrounded by filling material) were measured. RESULTS: The results revealed that none of the scanned root canal fillings were void-free. For I-voids, the volume fraction was significantly larger, but their number was lower (P=0.0007), than for S-voids. Both types of voids occurred in characteristic regions (P<0.001). I-voids occurred mainly in the apical third, while S-voids in the coronal third of the canal filling. CONCLUSIONS: Within the limitations of this study, our results indicate that microtomography, with proposed semi-automatic algorithm, is a useful tools for three-dimensional quantitative evaluation of dental root canal fillings. In canals filled with thermoplastic gutta-percha and Tubli-Seal, voids at the interface between the filling and canal dentine deserve special attention due to of their periapical location, which might promote apical microleakage. Further studies might help to elucidate the clinical relevance of these results.

Reacción del tejido celular subcutáneo de la rata a un sellador endodóntico a base de metacrilatos hidrófilos / Response of the subcutaneous connective tissue of the rat to a methacrylate-based endodontic sealer

Analizar la respuesta del tejido celular subcutáneo de la rata a la implantación de Epiphany, un sellador endodóntico a base de metacrilatos hidrófilos. Se implantaron tubos de silicona obturados a ras en ambos extremos con una preparación fresca de Epiphany o AH 26 en el tejido celular subcutáneo de veinte ratas; el AH 26 fue considerado como control positivo. Como control negativo se utilizaron tubos de silicona sin obturar. A los 14 días y a los 84 días posimplantación, los animales fueron sacrificados, los implantes junto con los tejidos circundantes fueron removidos, fijados en solución de formol al 10 por ciento y, finalmente, procesados para su estudio histológico. A los 14 días el análisis histológico reveló la presencia de una reacción inflamatoria severa compuesta por: polimorfonucleares neutrófilos, linfocitos, plasmocitos, macrófagos, fibroblastos y vasos de neoformación en contacto directo con Epiphany y AH 26. A los 84 días posimplantación, la reacción inflamatoria se redujo, pero persistió y fue considerada como moderada. En ambos períodos se observaron numerosas partículas de los dos materiales, dispersas en los tejidos, muchas de ellas fagocitadas por macrófagos, células gigantes multinucleadas y fibroblastos. En contacto con los controles negativos, la reacción de los tejidos fue considerada como mínima a los 14 días posimplantación, pero los tejidos retornaron a la normalidad al finalizar la experiencia. En ambos períodos se observaron diferencias significativas P<0.01 entre Epiphany/AH 26 y el control negativo, mientras que no las hubo P>0.05 entre ambos selladores. Cuando se compararon los resultados obtenidos en cada uno de los períodos experimentales 14 y 84 días, la diferencia fue estadísticamente significativa P<0.05 para cada uno de los materiales analizados.

Endodoncia adhesiva. Fundamentos, desarrollo y utilidad del sellador endodóntico a base de metacrilatos EndoREZ / Adhesive endodontics. Development and usefulness of the methacrylate resin-based endodontic sealer EndoREZ

Durante la última década se han incorporado al mercado una nueva generación de selladores endodónticos a base de metacrilatos hidrófilos, los que permiten obtener una adhesión efectiva a las paredes dentinarias y a los conos estandarizados provistos por el fabricante. El objetivoa de este trabajo es informar acerca de las propiedades, características específicas y utilidades del sellador a base de metacrilatos EndoREZ. Las investigaciones con su capacidad de sellado, biocompatibilidad y aplicación clínica sugieren que el EndoREZ es un material potencialmente efectivo para su uso clínico, y que su perfomance puede equipararse a la de los selladores endodónticos tradicionales.

Analysis of six heavy metals in Ortho mineral trioxide aggregate and ProRoot mineral trioxide aggregate by inductively coupled plasma-optical emission spectrometry.

Ortho mineral trioxide aggregate (MTA) is a mineral aggregate newly developed for perforation repair, root end filling and pulp capping. The aim of this study was to investigate the levels of cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn) in Ortho MTA and ProRoot MTA. A total of 0.2 g of each MTA was digested using a mixture of hydrochloric and nitric acids and filtered. Six heavy metals in the resulting filtrates were analyzed by inductively coupled plasma-optical emission spectrometry (n = 5). The results were statistically analyzed using the Mann-Whitney U-test. The concentrations of Cd, Cu, Fe, Mn, Ni and Zn in Ortho MTA were 0.10, 7.73, 49.51, 2.58, 0.82 and 10.09 p.p.m., respectively. The concentrations of Cd, Cu, Fe, Mn, Ni and Zn in ProRoot MTA were 0.16, 9.38, 1438.11, 74.51, 18.98 and 4.05 p.p.m., respectively. In conclusion, Ortho MTA had lower levels of Cd, Cu, Fe, Mn and Ni than ProRoot MTA.

Persistence of epoxy-based sealer residues in dentin treated with different chemical removal protocols.

The presence of residual endodontic sealer in the pulp chamber may cause discoloration of the dental crown and interfere with the adhesion of restorative materials. The aim of this study was to compare the efficacy of different solvents in removing residues of an epoxy resin-based sealer (AH Plus) from the dentin walls of the pulp chamber, by scanning electron microscopy (SEM). Forty-four bovine incisor dental crown fragments were treated with 17% EDTA and 2.5% NaOCl. Specimens received a coating of AH Plus and were left undisturbed for 5 min. Then, specimens were divided in four groups (n = 10) and cleaned with one of the following solutions: isopropyl alcohol, 95% ethanol, acetone solution, or amyl acetate solution. Negative controls (n = 2) did not receive AH Plus, while in positive controls (n = 2) the sealer was not removed. AH Plus removal was evaluated by SEM, and a score system was applied. Data were analyzed by Kruskal-Wallis and Dunn tests. None of the solutions tested was able to completely remove AH Plus from the dentin of the pulp chamber. Amyl acetate performed better than 95% ethanol and isopropyl alcohol (p < 0.05), but not better than acetone (p > 0.05) in removing the sealer from dentin. No significant differences were observed between acetone, 95% ethanol, and isopropyl alcohol (p > 0.05). It was concluded that amyl acetate and acetone may be good options for cleaning the pulp chamber after obturation with AH Plus.

Efeito do MTA Fillapex sobre a atividade de macrófagos peritoneais

A obturação do sistema de canais radiculares após a limpeza e modelagem é fundamental para o sucesso do tratamento endodôntico. Os materiais obturadores devem ter propriedades físicas e químicas favoráveis. Além disso, é altamente desejável que sejam biocompatíveis, porque, muitas vezes, são colocados em contato íntimo com os tecidos periapicais, através do forame e das comunicações acessórias apicais...

Assessment of diffusion of hydroxyl and calcium ions of root canal filling materials in primary teeth.

PURPOSE: The purpose of this study was to evaluate the diffusion of hydroxyl (OH-) and calcium (Ca+2) of 2 intracanal calcium hydroxide-based medications through the root dentin and cementum of primary teeth. METHODS: Forty roots were selected and a single operator instrumented the canals. The irrigation was performed with a 1% sodium hypochlorite solution, and a final irrigation used 17% ethylenediaminetetraacetic acid solution. The teeth were divided into 3 groups: (1) group 1 (N=15)- thickened calcium hydroxide paste blended with propylene glycol paste; (2) group 2 (N=15)-Calen; and (3) group 3 (N=10)-no medication. Diffusion of the OH-ions was determined using a digital pH meter, and diffusion of Ca+2 ions was determined through atomic absorption spectrometry at baseline, 24 hours, 7 days, 15 days, and 30 days later. RESULTS: Two-way analysis of variance and Tukey's test revealed that Group 1 achieved significantly higher pH values (P<.01), followed by Groups 2 and 3. There was a statistically significant difference between groups (P<.01) in the amount of Ca+2 ions released; group 1 had the highest diffusion values, followed by group 2, both with peak diffusion at 7 days. CONCLUSIONS: Thickened calcium hydroxide paste blended with propylene glycol paste achieved the greatest diffusion of hydroxyl and calcium through the dentin and cementum of primary teeth.