Bacterial sealing ability of calcium silicate-based sealer for endodontic surgery: an in-vitro study.

BACKGROUND: Apical surgery with standard retrograde maneuvers may be challenging in certain cases. Simplifying apical surgery to reduce operating time and streamline retrograde manipulation is an emerging need in clinical endodontics. AIM OF THE STUDY: The aim of the study was to compare the bacterial sealing ability of a calcium silicate-based sealer with the single cone technique combined with root end resection only, and calcium silicate-based sealer as a retrograde filling versus MTA retrofilling, and to analyze bacterial viability using confocal laser scanning microscope (CLSM). MATERIALS AND METHODS: In this in vitro experimental study, 50 extracted human maxillary incisor teeth were instrumented and randomly divided into five groups: three experimental groups, a positive control group, and a negative control group (n = 10/group). In the experimental groups, the roots were obturated using the single cone technique (SCT) and a calcium silicate-based sealer. In group 1, the roots were resected 3 mm from the apex with no further retrograde preparation or filling. In groups 2 and 3, the roots were resected, retroprepared, and retrofilled with either a calcium silicate-based sealer or MTA, respectively. Group 4 (positive control) was filled with a single gutta-percha cone without any sealer. In group 5 (negative control), the canals were left empty, and the roots were sealed with wax and nail varnish. A bacterial leakage model using Enterococcus faecalis was employed to assess the sealing ability over a 30-day period, checking for turbidity and analyzing colony forming units (CFUs) per milliliter. Five specimens from each group were examined using CLSM for bacterial viability. Data for the bacterial sealing ability were statistically analyzed using chi-squared and Kruskal-Wallis tests. RESULTS: The three experimental groups did not show significant differences in terms of bacterial leakage, or bacterial counts (CFUs) (P > 0.05). However, significant differences were observed when comparing the experimental groups to the positive control group. Notably, the calcium silicate-based sealer, when used as a retrofilling, yielded the best sealing ability. CLSM imaging revealed viable bacterial penetration in all the positive control group specimens while for the experimental groups, dead bacteria was the prominent feature seen. CONCLUSION: Within the limitations of this study, it could be concluded that the bacterial sealing ability of calcium silicate-based sealer with the single cone technique combined with root end resection only and calcium silicate-based sealer as a retrograde filling were comparable with MTA retrofilling during endodontic surgical procedures.

Effect of sodium hypochlorite and calcium hypochlorite on the apical sealing ability of endodontic sealers

Aim: This study aimed to compare the influence of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2 ] on the apical sealing capacity of AH Plus (Dentsply Maillefer) and Bio-C Sealer (Angelus) endodontic sealers. Methods: Sixty permanent human lower incisors were randomly allocated (http://www.randomized.org), according to the irrigant used, into three groups (n=20): 0.9% sodium chloride (NaCl/Control); 2.5% NaOCl; and 2.5% Ca(OCl)2 . The root canal was prepared with rotary files under 10 mL of the solution corresponding to the experimental group. Each group was subdivided into two (n=10) according to the sealer used for filling: AH Plus (Dentsply Maillefer) or Bio-C Sealer (Angelus). Then, all samples were immersed in black India ink for one week. After the storage period, the roots were then grooved longitudinally and split, and the ink penetration was measured from the apical part to the coronal part of the root canal into which the ink penetrated using a stereomicroscope. Data were analyzed by one-way ANOVA and Tukey's post-hoc tests. Results: There was no statistical difference in ink penetration between the different endodontic sealers tested for the same irrigating solution (p > 0.05). However, when the Bio-C Sealer (Angelus) was used, the group treated with 2.5% Ca(OCl)2 was associated with lower values of apical leakage, compared to 2.5% NaOCl (p < 0.05). For the AH Plus sealer (Dentsply Maillefer), there was no difference between the irrigants (p > 0.05). Conclusions: Associating Ca(OCl)2 irrigant with Bio-C Sealer (Angelus) seems to be a good option to reduce apical leakage

Evaluación de la filtración apical al utilizar dos selladores biocerámicos / Evaluation of apical leakage when using two bioceramic sealers

Objetivo: Evaluar con técnica de diafanización el gra-do de filtración apical al utilizar dos selladores bio-cerámicos y la técnica de cono único con taper ex vivo. Materiales y métodos: Se utilizaron 60 premola-res inferiores humanos uniradiculares extraídos. La instrumentación se realizó con lima Primary 25/.07 (WaveOne Gold, Dentsply Maillefer), según protocolo del fabricante. Se irrigó con NaOCl 2,5% y EDTAC 17%. Para la obturación, la muestra se dividió aleatoria-mente en 4 grupos (n=15). Grupo 1: Cono único y Bio C Sealer. Grupo 2: Cono único y MTA Fillapex. Grupo control negativo: no se obturó. Grupo control positi-vo: Cono único y AH Plus. En todas las muestras se aplicaron dos capas de esmalte para uñas en toda la superficie dentaria con excepción del tercio apical y del grupo control positivo, que se esmaltó en su tota-lidad. Medio de filtración: tinta china negra por difu-sión pasiva. Se diafanizó con técnica de Robertson. Se usó programa AutoCad 2022, para medir filtración en milímetros lineales. Los datos se analizaron me-diante prueba de Kruskal-Wallis seguida por compa-raciones post hoc empleando el método de Conover (p<0,05, significativo). Resultados: La filtración con Bio C Sealer, MTA Fillapex, control negativo y control positivo tuvo una media (mínimo-máximo) de 0 (0-2), 1 (0-3), 6 (2-12) y 0 (0-0); sin diferencias significativas entre Bio C Sealer y MTA Fillapex (p>0,05), ni entre Bio C Sealer y control positivo (p>0,05); pero con di-ferencias significativas entre MTA Fillapex y control positivo (p<0,05), y entre control negativo y cual-quiera de los otros tres grupos (p<0,05). Conclusión: La obturación con Bio C Sealer lograría un nivel de sellado similar al que se obtiene con el control po-sitivo; mientras que la obturación con MTA Fillapex produciría un sellado ligeramente menos efectivo que el control positivo. Sin embargo, la filtración no variaría sustancialmente entre obturaciones con Bio C Sealer y MTA Fillapex (AU)

Objective: To evaluate the degree of apical filtration with diaphanization technique, using two bioceramic sealers and single cone technique with taper, ex vivo. Materials and methods: 60 extracted single-root human mandibular premolars were used. The instrumentation was carried out with primary file 25/.07 (WaveOne Gold, Dentsply Maillefer), according to the manufacturer's protocol. Irrigation was done with 2.5% NaOCl and 17% EDTAC. For obturation, the sample was randomly divided in 4 groups (n=15). Group 1: Single cone and Bio C Sealer. Group 2: Single cone and MTA Fillapex. Negative control group: it was not obturated. Positive control group: Single cone and AH Plus. In all samples, two layers of nail polish were applied to the entire tooth surface with exception of apical third and the positive control group, which was completely glazed. Filtration medium: black Chinese ink by passive diffusion. It was diaphanized with Robertson technique. AutoCad 2022 program was used to measure filtration in linear millimeters. Data were analyzed using Kruskal-Wallis test, followed by post hoc comparisons using Conover method (p < 0.05, significant). Results: Filtration with Bio C Sealer, MTA Fillapex, negative control and positive control had a mean (minimum-maximum) of 0 (0-2), 1 (0-3), 6 (2-12) and 0 (0-0); no significant differences between Bio C Sealer and MTA Fillapex (p > 0.05), nor between Bio C Sealer and positive control (p > 0.05); but with significant differences between MTA Fillapex and positive control (p < 0.05), and between negative control and any of the other three groups (p < 0.05). Conclusion: Obturation with Bio C Sealer would achieve a level of sealing similar to obtained with the positive control; while obturation with MTA Fillapex would produce a slightly less effective seal than the positive control. However, filtration would not vary substantially between fillings with Bio C Sealer and MTA Fillapex (AU)

Protocolo para la medición de espacios vacíos dentro de la obturación endodóntica con microtomografía / A protocol for the measurement of voids within the endodontic filling with microtomography

La microtomografía es un estudio que utiliza la ra-diación X para obtener imágenes de tamaños de mi-lésimas de milímetros y de alta resolución. Las imá-genes 2D son procesadas por diferentes softwares para lograr obtener volúmenes capaces de ser ana-lizados tridimensionalmente. La microtomografía es el estudio de elección a la hora de evaluar caracte-rísticas muy pequeñas con gran precisión. La obtu-ración endodóntica buscar lograr un sellado que no tenga espacios vacíos dentro de la masa de obtura-ción. Esto es importante debido a que los poros pue-den permitir, si están en contacto con la pared den-tinaria, la entrada de microorganismos al conducto radicular. El objetivo de este trabajo fue describir el procedimiento para el análisis y visualización de los espacios vacíos dentro de la obturación endodónti-ca, utilizando la microtomografía de rayos x, y esta-blecer un protocolo para ser utilizado por cualquier investigador(AU)

Microtomography is a study that uses X-radiation to obtain high-resolution images of sizes of thousandths of millimeters. The 2D images are processed by different software to obtain volumes capable of being analyzed three-dimensionally. Microtomography is the study of choice when evaluating very small features with great precision. Endodontic filling seeks to achieve a seal that does not have voids within the filling obturation. This is important because the voids can allow, if they are in contact with the dentin wall, the entry of microorganisms into the root canal. The objective of this work was to describe the procedure for the analysis and visualization of voids within the endodontic filling using microtomography and to establish the protocol to be used by any researcher (AU)

In vitro comparison of marginal infiltration between a conventional resin and a bulk-fill resin, in the relocation of cervical margins technique / Comparación in vitro de la infiltración marginal entre una resina convencional y una resina bulk-fill, en la técnica de reubicación de márgenes cervicales

Introduction: Proximal lesions that exceed the cement enamel limit (ACE) under the gingival margin complicate impressions and the adhesive technique. Compare the magnitude of micro infiltration between conventional resin and bulk fill resin in the cervical margin relocation technique. Materials and Methods: 48 samples of human teeth re-ceived two preparations: occluso-mesial (OM) and occluso-distal (OD) under LAC; first they received the cervical margin relocation technique (RMC) with bulk fill and conventional resin; then restored with semi-direct resinous inlays. Sample analysis: immersion in 50% colloidal silver nitrate solution, 24 hours, 37°C and cut mesiodistally. Observed under a stereoscopic magnifying glass to assess dye penetration and digitally photographed, analyzed with "Image J" software. Results: Sample of 96 cavities in two groups of 48 units; control group restored with conventional resin with incremental technique and study group restored with bulk fill resin, mono-incremental technique. Probabilistic sampling. No statistically significant diffe-rences in percentage of microinfiltrated area between Filtek™ Z250™ and Filtek™ Bulk Fill™ (p-value= 0.68). Discussion: Various studies show that the presence of marginal microinfiltration exist independent of: restorative technique, consistency, adhesive mechanism and polyme-rization technique. The research carried out is no exception, observing a similar degree for both systems. Conclusions: Results allow us to conclude that conventi-onal resin and bulk fill resin did not show significant differences in microleakage percentages for the RMC technique. Outside the study framework, bulk fill resins would have comparative advantages; better behavior against light in depths greater than 2 mm, less sensitivity to the "C" factor, and less clinical time.

Introducción: Las lesiones proximales que superan el límite cemento esmalte (ACE) por debajo del margen gingival complican las impresiones y la técnica adhesiva. Comparar la magnitud de la microinfiltración entre la resina convencional y la resina de relleno en la técnica de reubicación del margen cervical. Materiales y Métodos: 48 muestras de dientes humanos recibieron dos preparaciones: ocluso-mesial (OM) y ocluso-distal (OD) bajo LAC, primero recibieron la técnica de reubicación del margen cervical (RMC) con relleno en bloque y resina convencional; luego restaurado con incrustaciones resinosas semidirectas. Análisis de la muestra: inmersión en solución de nitrato de plata coloidal al 50%, 24 horas, 37°C y corte mesiodistal. Observado bajo una lupa estereoscópica para evaluar la penetración del tinte y fotografiado digitalmente, analizado con el software "Image J". Resultados: Muestra de 96 cavidades en dos grupos de 48 unidades; grupo control restaurado con resina convencional con técnica incremental y grupo estudio restaurado con resina bulk fill, técnica mono-incremental. Muestreo probabilístico. No hubo diferencias estadísticamente significativas en el porcentaje de área microinfiltrada entre Filtek™ Z250™ y Filtek™ Bulk Fill™ (p-value = 0,68) Discusión: Diversos estudios evidencian presencia de microinfiltración marginal, independiente de técnica restauradora, consistencia, mecanismo adhesivo y técnica polimerizadora. La investigación realizada no es excepción, observándose grado similar para ambos sistemas. Conclusiones: Los resultados permiten concluir que resina convencional y resina bulk fill no presentaron diferencias significativas en porcentajes de microinfiltración para técnica RMC. Fuera del marco del estudio, resinas bulk fill tendrían ventajas comparativas; mejor comportamiento frente a la luz en profundidades superiores a 2 mm, menor sensibilidad al factor "C", y menor tiempo clínico.

Capacidad de sellado apical entre dos técnicas de obturación con instrumentos rotatorios fracturados en tercio apical / Apical sealing capacity between two obturation techniques with rotary instruments broken in third apical

Introducción: La finalidad del tratamiento de conductos es conseguir la máxima desinfección, conformación y sellado tridimensional. Objetivo: Comparar la capacidad del sellado apical entre dos técnicas de obturación en conductos mesiales de molares inferiores con limas fracturadas en tercio apical. Material y métodos: Se utilizaron 60 raíces mesiales de molares inferiores, instrumentados con Protaper Universal, se desgastó 4 milímetros la parte activa del instrumento y se fracturó intencionalmente en tercio apical. Se formaron dos grupos de 30 raíces mesiales (n = 30) cada uno y se utilizaron dos técnicas de obturación: grupo 1: condensación lateral clásica y grupo 2: Obtura II. Las muestras se sumergieron en tubos de ensayo y en su interior contenían 5 mL de tinta china, se diafanizaron y observaron con un microscopio estereoscópico (LEICA, EZ4D) a 35x para medir la penetración de tinta china dentro del conducto radicular. Resultados: Se encontró una mayor microfiltración apical con suficiente evidencia estadística en el grupo de Obtura II comparado con el grupo de condensación lateral clásica (p < 0.002). Conclusiones: Ambos grupos presentaron microfiltración apical; sin embargo, en el grupo que se utilizó el sistema de obturación termoplastificada Obtura II se detectó mayor filtración apical comparada con el grupo de condensación lateral clásica (AU)

Introduction: The purpose of root canal treatment is to achieve maximum disinfection, shaping and three-dimensional sealing. Objective: To compare the apical sealing capacity between two obturation techniques in mesial canals of mandibular molars with broken files in the apical third. Material and methods: 60 mesial roots of lower molars were used, instrumented with Protaper Universal, the active part of the instrument was worn by 4 millimeters and it was intentionally broken in the apical third. Two groups of 30 mesial roots (n = 30) each were formed and two filling techniques were used: group 1: classic lateral condensation and group 2: Obtura II. The samples were immersed in test tubes and contained 5 mL of Chinese ink inside, they were clear and observed with a stereomicroscope (LEICA, EZ4D) at 35x to measure the penetration of Chinese ink into the root canal. Results: A higher apical microfiltration with sufficient statistical evidence was found in the Obtura II group compared to the classic lateral condensation group (p < 0.002). Conclusions: Both groups presented apical microfiltration, however, in the group that used the Obtura II thermoplastic obturation system, greater apical filtration was detected compared to the classic lateral condensation group (AU)

Effect of liners on composite resin microleakage after selective carious lesion removal: an experimental study / Efecto de los recubrimiento en la microfiltración de resina compuesta después de la eliminación selectiva de lesiones cariosas: un estudio experimental

Objetive: To evaluate microleakage of composite resins (CR) placed over different cavitary liners after managing deep caries lesions through selective removal of soft carious tissue to soft dentin (SRCT-S). Material and Methods: Fifty four human teeth were collected for microleakage testing. Each assay comprised ICDAS 5 or ICDAS 6 carious lesions and sound teeth for controls. Sound teeth were prepared with cavities that mirrored the carious teeth cavities, which were prepared with SRCT-S. Sound and carious teeth were further randomly assigned to one of the three experimental groups: Group A: universal adhesive (UA) + CR, Group B: glass ionomer cement liner + UA + CR, and Group C: calcium hydroxide + UA+ CR. Occlusal microleakage (OM) and cervical microleakage (CM) was classified within one of 5 depth categories. ANOVA and Chi-square tests were computed (p<0.05). Results: OM and CM were similarly distributed across subgroups (p>0.05). All Group C samples with carious lesions presented some degree of microleakage. However, no statistically significant differences were observed between groups and within each group (p>0.05). Conclusion: Teeth restored with CR after SRCT-S using calcium hydroxide as a liner material seem to exhibit higher microleakage than those restored using glass ionomer or UA alone. Further clinical research is needed to deepen these findings. Clinical significance: The application of calcium hydroxide as a liner under a composite resin may reduce the longevity of a restoration after performing selective or partial removal of carious tissues. Clinicians should rethink the need of using calcium hydroxide for this application, albeit the lack of clinical evidence.

Objetivo: Evaluar la microfiltración de resinas compuestas (RC) colocadas sobre diferentes liners cavitarios después del manejo de lesiones de caries profundas mediante la remoción selectiva de tejido cariado blando hasta dentina blanda (SRCT-S). Material y Métodos: Se recolectaron 54 dientes humanos para pruebas de microfiltración. Cada ensayo comprendía lesiones cariosas ICDAS 5 o ICDAS 6 y dientes sanos para los controles. Se prepararon dientes sanos con cavidades que reflejaban las cavidades de los dientes cariados, que se prepararon con SRCT-S. Los dientes sanos y cariados se asignaron al azar a uno de los tres grupos experimentales: Grupo A: adhesivo universal (AU) + RC, Grupo B: revestimiento de cemento de ionómero de vidrio + AU + RC, y Grupo C: hidróxido de calcio + AU+ RC. La microfiltración oclusal (MO) y la microfiltración cervical (MC) se clasificaron dentro de una de las 5 categorías de profundidad. Se calcularon las pruebas ANOVA y Chi-cuadrado (p<0,05). Resultados: La MO y MC se distribuyeron de manera similar en los subgrupos (p> 0,05). Todas las muestras del Grupo C con lesiones cariosas presentaron algún grado de microfiltración. Sin embargo, no se observaron diferencias estadísticamente significativas entre grupos y dentro de cada grupo (p>0,05). Conclusión: Los dientes restaurados con RC después de SRCT-S usando hidróxido de calcio como material de revestimiento parecen exhibir una mayor microfiltración que aquellos restaurados usando ionómero de vidrio o AU solo. Se necesita más investigación clínica para profundizar estos hallazgos. Relevancia clínica: la aplicación de hidróxido de calcio como revestimiento debajo de una resina compuesta puede reducir la longevidad de una restauración después de realizar la eliminación selectiva o parcial de los tejidos cariados. Los médicos deberían reconsiderar la necesidad de usar hidróxido de calcio para esta aplicación, aunque no haya evidencia clínica.

Sealing ability of two root-end filling materials at different retro-preparation lengths.

PURPOSE: The aim of the present study was to evaluate the sealing performance, expressed as microleakage (ML), of two root-end filling materials when used at different retro-preparation lengths. METHODS: Fifty single-rooted human teeth were collected for the study. The teeth were cut at the cement-enamel junction and endodontic treatment was performed. Each root was cut at 3 mm from the apex and then stored in wet condition. The teeth were divided into three groups according to the retro-preparation length: control group (no retro-preparation); group 1 (retro-preparation of 3 mm); group 2 (retro-preparation of 9 mm). The teeth were equally allocated to either Biodentine or Super EBA treatment group. The teeth were immersed in 3% methylene blue dye solution for 24 h. The samples were split longitudinally and the depth of dye penetration was examined through light microscopy. RESULTS: No significant statistical differences were found at different retro-preparation lengths (P > 0.05). Differences were found between materials (P > 0.05). CONCLUSION: Biodentine showed significantly lower ML when compared to Super-EBA and no statistical significative differences were observed when samples were retro-prepared at 3 mm or 9 mm.

Evaluation of Microleakage at the Junction Between Combined Amalgam/Composite Resin Restorations Using Different Bonding Systems in Class II Cavities

Abstract Objective: To evaluate the microleakage at the junction between amalgam-composite resin restorations using different bonding systems. Material and Methods: In this in-vitro study, standard class II cavities were prepared on 40 human maxillary premolars. The axial and gingival floor depths of the cavities were 2 mm and 1 mm below (cementoenamel junction), respectively. The samples were divided into 4 groups (n = 10). In all groups, a layer of 1-mm thick amalgam was used as a coating for the initial part of the gingival floor. In group 1, no bonding system was used for amalgam restoration. In group 2, G-Premio Bond was applied. G-Premio bond + alloy primer and single bond + alloy primer were used in group 3 and group 4, respectively. The rest of the cavities in all groups were then repaired using FiltekZ250 composite. The samples were thermocycled at 500 rpm and immersed in 1% methylene blue solution for 24 hours to allow dye penetration. Once cut, the samples were placed under a stereomicroscope (40X) to determine the microleakage rate. Data analysis was carried out using post-hoc and Chi-square tests (p<0.05). Results: The highest and lowest microleakage rate was related to groups 1 and 3, respectively. There was a significant difference between groups (1,2) and (1,3), and (1,4), and groups (2,3) (p<0.05). Conclusion: The use of alloy primer and bonding could reduce the microleakage between the two restorations (AU).

Effect of resin infiltration and bleaching on surface roughness and microhardness of human enamel with induced white spot lesions / Efeito do infiltrante resinoso e do clareamento na rugosidade e microdureza de superfície do esmalte humano com lesões de mancha branca induzidas

Objective: To comparatively evaluate the effect of resin infiltration, bleaching and bleaching followed by resin infiltration on the surface roughness and microhardness of human enamel with induced white spot lesions (WSLs) and their resistance to acidic challenge. Material and Methods: Sixty human specimens were randomly divided into three groups (n=20) according to the treatment modality applied; group I Icon® resin infiltration, group II bleaching and group III bleaching followed by Icon® resin infiltration. For each treatment modality, 10 specimens were tested for surface roughness and another 10 for microhardness. WSLs were artificially induced in all specimens and after treatment, all specimens were subjected to acidic challenge. Surface roughness was measured by the tapping mode of the atomic force microscope (AFM) and microhardness was measured by digital Vickers hardness tester at baseline, after induction of WSLs, after treatment and after acidic challenge. Results: Groups I and III showed significant reduction in surface roughness after treatment, while group II showed significant increase. Groups I and III showed significant increase in the microhardness after treatment, while group II showed insignificant increase. The three tested groups showed significant increase in surface roughness values and significant reduction in microhardness after acidic challenge. Conclusion: Resin infiltration and bleaching followed by resin infiltration reduced the surface roughness and enhanced the microhardness of the WSLs. The three treatment modalities failed to resist acidic challenge resulting in increasing surface roughness and reducing microhardness. (AU)

Objetivo: Avaliar comparativamente o efeito do infiltrante resinoso, clareamento e clareamento seguido de infiltração resinosa sobre a rugosidade e microdureza superficial do esmalte humano com lesões de manchas brancas induzidas (WSLs) e sua resistência ao desafio erosivo. Material e Métodos: Sessenta espécimes humanos foram divididos aleatoriamente em três grupos (n = 20) de acordo com a modalidade de tratamento aplicada; grupo I infiltrante resinoso Icon®, grupo II clareamento e grupo III clareamento seguido de infiltração resinosa Icon®. Para cada modalidade de tratamento, 10 corpos-de-prova foram testados para rugosidade superficial e outros 10 para microdureza. WSLs foram artificialmente induzidos em todas as amostras e, após o tratamento, todas as amostras foram submetidas ao desafio erosivo. A rugosidade de superfície foi medida por microscopia de força atômica em modo de contato intermitente (AFM) e a microdureza Vickers foi medida inicialmente, após a indução de WSLs, após o tratamento e após o desafio ácido. Resultados: Os grupos I e III apresentaram redução significativa da rugosidade superficial após o tratamento, enquanto o grupo II apresentou aumento significativo. Os grupos I e III apresentaram aumento significativo na microdureza após o tratamento, enquanto o grupo II apresentou aumento insignificante. Os três grupos testados mostraram aumento significativo nos valores de rugosidade superficial e redução significativa na microdureza após o desafio erosivo. Conclusão: O infiltrante resinoso e o clareamento seguido de infiltração resinosa reduziram a rugosidade de superfície e aumentaram a microdureza dos WSLs. As três modalidades de tratamento falharam em resistir ao desafio erosivo, resultando em aumento da rugosidade de superfície e redução da microdureza.(AU)

Effectiveness of local and topical anesthesia during gingival retraction / Eficácia da anestesia local e tópica durante a retração gingival

Objective: To compare the effectiveness of local and topical anesthesia during gingival retraction in prepared abutment teeth. Material and Methods: 72 patients desiring full mouth rehabilitation or bilateral fixed partial denture in the same arch were selected based on the inclusion criteria framed and were randomly allocated into Groups A and B of 36 each. Patients in Group A received gingival retraction with topical anesthesia and Group B received gingival retraction with infiltration anesthesia. All the patients were tested for pain, discomfort and bleeding during gingival retraction. Results: There was no significant difference in pain, discomfort and gingival bleeding (P >.05) during gingival retraction using topical and local anesthetic agents. Conclusion: Topical anesthesia was equally effective as infiltration anesthesia in managing the pain, discomfort and bleeding during gingival retraction by cord packing in prepared abutment teeth. (AU)

Objetivo: Comparar a eficácia da anestesia local e tópica durante a retração gengival previa a moldagem em dentes pilares preparados. Material e Métodos: Foram selecionados 72 pacientes indicados para reabilitação bucal total ou prótese parcial fixa bilateral na mesma arcada com base nos critérios de inclusão formulados e alocados aleatoriamente nos Grupos A e B com 36 pacientes cada. Os pacientes do Grupo A receberam retração gengival com anestesia tópica e no Grupo B receberam retração gengival com anestesia infiltrativa. Todos os pacientes foram testados para dor, desconforto e sangramento durante o procedimento. Resultados: Não houve diferença significativa na dor, desconforto e sangramento gengival (P>. 05) durante a retração gengival com anestésicos tópicos e locais. Conclusão: A anestesia tópica foi tão eficaz quanto a anestesia de infiltração no controle da dor, desconforto e sangramento durante a retração gengival com fio retrator gengival em dentes pilares preparados.(AU)

Influence of laser deproteinization of acid-etched dentin on marginal microleakage of class V composite restoration

Aim: Recent reports indicate that deproteinization of acid-etched dentin surface can extend penetration depth of adhesive agents. The main goal of the present research was to investigate the deproteinization effect of Nd:YAG and diode 940 lasers on acid-etched dentin and microleakage grade in class V composite restorations. Methods: 36 extracted human premolar teeth were selected to make standard buccal and lingual class V cavities. These samples were randomly split into three sub-groups: 1.Control group, in which composite was applied for restoration after etch and bonding process without deproteinization; 2.Nd:YAG laser group, in which the teeth were deproteinized with Nd:YAG laser after etching and painting internal surfaces of cavities with Van Geison stain and then composite restorations applied just as control group; 3.Diode laser group, in which the process was similar to Nd:YAG laser group, but instead, diode 940 laser was irradiated. The teeth were bisected into two equal longitudinal buccal and lingual halves. Marginal microleakage of samples was scored by using a stereomicroscope. Kruskal- Wallis, Mann-Whitney U and Fisher's statistical tests were employed for analysis of the obtained data. Results: A significant reduction in marginal microleakage was observed for both groups treated with laser (Nd:YAG and diode 940)compared to control (p=0.001 & p=0.047). There was no significant difference in marginal microleakage between Nd:YAG laser and diode 940groups (P = 0.333). Conclusion: Nd:YAG and diode 940 laser deproteinization of acid-etched dentin decreased the marginal microleakage of in-vitro class V resin composite restorations

Comparison of microleakage of an alkasite restorative material, a composite resin and a resin-modified glass ionomer

Aim: To compare the microleakage of Cention N, a subgroup of composite resins with a resin-modified glass ionomer (RMGI) and a composite resin. Methods: Class V cavities were prepared on the buccal and lingual surfaces of 46 extracted human molars. The teeth were randomly assigned to four groups. Group A: Tetric N-Bond etch-and-rinse adhesive and Tetric N-Ceram nanohybrid composite resin, group B: Cention N without adhesive, group C: Cention N with adhesive, and group D: Fuji II LC RMGI. The teeth were thermocycled between 5°-55°C (×10,000). The teeth were coated with two layers of nail vanish except for 1 mm around the restoration margins, and immersed in 2% methylene blue (37°C, 24 h) before buccolingual sectioning to evaluate dye penetration under a stereomicroscope (×20). The data were analyzed by the Kruskal-Wallis and Wilcoxon tests (α=0.05). Results: Type of material and restoration margin had significant effects on the microleakage (p<0.05). Dentin margins showed a higher leakage score in all groups. Cention N and RMGI groups showed significant differences at the enamel margin (p=0.025, p=0.011), and for the latter group the scores were higher. No significant difference was found at the dentin margins between the materials except between Cention N with adhesive and RMGI (p=0.031). Conclusion: Microleakage was evident in all three restorative materials. Cention N groups showed similar microleakage scores to the composite resin and displayed lower microleakage scores compared with RMGI

Capacidad de sellado de los conductos laterales con distintas técnicas de obturación del conducto radicular / Sealing capacity of lateral canals with different root canal obturation techniques

Objetivo: Estimar y comparar la eficacia de diferentes técnicas de obturación para impedir el flujo de colorante a través de los conductos laterales. Materiales y métodos: Se emplearon 50 premolares inferiores extraídos y conservados en formol neutro al 5% hasta el momento de su uso, a los cuales se les realizaron conductos laterales artificiales. Una vez instrumentados los conductos principales, los dientes fueron divididos al azar en 5 grupos (n=10) para ser obturados con cuatro técnicas distintas: A) System B + inyección de gutapercha termoplástica del sistema Elements, Extruder; B) obturadores de Thermafil, ProTaper Universal; C) técnica híbrida y D) obturación con inyección de gutapercha termoplástica del sistema Elements, Extruder. Inmersos en tinta china y diafanizadas las raíces, se evaluó la longitud de penetración de la tinta en los conductos laterales. Se empleó el análisis de la varianza para detectar diferencias significativas (P<0,05) entre los niveles medios de penetración del colorante según las técnicas de obturación y las zonas del diente, y se efectuaron pruebas de rango múltiple (HSD de Tukey) para realizar comparaciones dos a dos, manteniendo fija la tasa de error por familia. Resultados: A la técnica B le correspondió el valor medio más bajo (30,63%) de penetración de tinta china. Los valores medios más elevados (54,52% y 51,74%) correspondieron a las técnicas A y C, respectivamente. Conclusión: Ninguna de las técnicas de obturación del conducto radicular empleadas ha sido capaz de impedir la filtración del colorante en los conductos laterales (AU)

Aim: To estimate and compare the different obturation techniques to avoid the flow of colorant through lateral canals. Materials and methods: 50 extracted lower premolars preserved in 5% neutral formol until the moment of use, had artificial lateral canals made. Once canals were instrumented, the teeth were randomly divided into 5 groups (n=10) to be filled with four different techniques: A) System B + injection of thermoplastic gutta-percha, Elements system, Extruder; B) Thermafil, ProTaper Universal obturators; C) hybrid technique, and D) injection of thermoplastic gutta-percha, Elements system, Extruder. Having immersed the premolars in India ink and diaphanized the roots, the penetration length of the India ink inside the canals was assessed. Analysis of variance was used to detect significant differences (P<0.05) between the mean levels of dye penetration according to the filling techniques and tooth areas, and multiple range tests (Tukey's HSD) were performed for two-to-two comparisons, keeping the error rate per family fixed. Results: Technique B had the lowest mean value (30.63%) of penetration. The highest mean values (54.52% and 51.74%) corresponded to techniques A and C, respectively. Conclusion: No obturation technique of the root canal used was able to avoid filtration of colourant in the lateral canals (AU)

[Effect of different pretreatment methods on dentin microleakage and bonding effect in caries].

PURPOSE：To evaluate the effect of different pretreatment methods on dentin microleakage and bonding effect of caries, so as to provide reference for clinical practice. METHODS: Sixty isolated caries were collected from Department of Oral and Maxillofacial Surgery, Affiliated Stomatological Hospital of Nanchang University from January 2020 to December 2020, and 120 dental samples were obtained by grinding them into two halves along the long axis of the precursor teeth. According to different pretreatment methods, they were divided into group A (2%NaClO), group B (2% chlorhexidine) and group C (75% ethanol). The bond strength, microtensile test and microleakage of the three groups of teeth were compared. SPSS 24.0 software package was used for statistical analysis of the data. RESULTS: The bond strength of the three groups from high to low was group A, group B and group C(P＜0.05); the fracture type of the three groups was compared, mixed damage of group A was lower than that of group B and group C； microleakage of the three groups was compared, and microleakage of group A was better than that of group B and group C(P＜0.05). CONCLUSIONS: Pre-treatment with 2%NaClO can reduce dentin microleakage and significantly improve the bonding strength of teeth, which is conducive to the promotion and application in the treatment of dental diseases.

Effects of magnetic resonance imaging on the microleakage of five restorative materials: An in vitro study.

OBJECTIVE: The objective of this study was to assess the effects of 3 T magnetic resonance imaging (MRI) on the microleakage of 5 restorative materials. METHODS: In total, 100 maxillary molars were randomly assigned to 5 groups (n = 20) for restoration with 5 different materials: amalgam, light-cured glass-ionomer cement, feldspathic porcelain fused to metal, pressed lithium disilicate glass ceramic, and composite resin. In each group, 10 specimens were subjected to MRI, and 10 specimens served as controls with no MRI exposure. Standardized class V cavities were prepared with occlusal margins terminating in enamel and gingival margins terminating in dentin. Microleakage penetration at the enamel and dentin margins was calculated for each group. A chi-square test was used for intergroup comparisons. Statistical significance was established at P < .05. RESULTS: Microleakage penetration did not differ significantly between specimens subjected to MRI and the controls for any restoration (P ≥ .362 for the enamel margin, P ≥ .067 for the dentin margin) or between specimens treated with different restorative materials (P ≥ .355). No significant differences in microleakage were discovered between the enamel and dentin margins of any of the restorative groups (P ≥ .236). CONCLUSION: MRI had no effect on the microleakage of the 5 restorative materials.

Resolução estética de lesões de mancha branca pós-tratamento ortodôntico / Esthetic resolution of white spot lesions after orthodontic treatment

O objetivo deste estudo foi comparar as técnicas de microabrasão de esmalte (ME) e infiltração de resina (IR) em relação à resolução estética de lesões cariosas de mancha branca (LCMB) e avaliar a correlação entre a luminosidade das lesões quando transiluminadas e a resolução do problema (estudo 1); avaliar em um estudo "in vitro", a eficácia do clareamento dental, em amostras de dentes submetidos previamente a IR (estudo 2); avaliar a efetividade do clareamento dental 12 meses após a realização dos protocolos de mínima intervenção, em um estudo de série de casos (estudo 3). Para o estudo 1 foram selecionados 17 pacientes que foram divididos em 2 grupos: ME (N=8) e IR (N=9). Um dente de cada paciente foi fotografado sob condição normal e do mesmo dente com auxilio de dispositivo translume. Em seguida os pacientes foram submetidos às técnicas de mínima intervenção. Após 7 dias de acompanhamento, o mesmo protocolo fotográfico foi realizado. Para resolução estética, foi delimitado a área do dente em relação a área da mancha por software. Para avaliação da cor da mancha quando evidenciada, os valores de luminosidade (L*) das coordenadas L*a*b* foram avaliados antes e após a intervenção, sendo mensurados valores das áreas sadias e área da mancha mais enegrecida. Os dados de correlação foram submetidos ao teste de Person. A resolutividade dos tratamentos foi dada por um Teste t-Student e a diferença de luminosidade antes e após os tratamentos foi dado pelo teste Anova 2 fatores de medidas repetidas (p<0,05). Para o estudo 2, quarenta superfícies de esmalte bovino foram submetidas à desmineralização. Após, foram estabelecidos dois protocolos de manchamento. Vinte espécimes foram imersos em caldo de manchamento por 24 horas (Lab 1) ou 7 dias (Lab 2). Dez corpos-de-prova de cada grupo receberam a aplicação de IR. Todas as amostras foram clareadas com gel de peróxido de carbamida 15% por 14 dias (8 horas diárias). A mensuração da cor foi realizada em espectrofotômetro de refletância em três momentos: inicial, após o manchamento e após o clareamento. Os dados (CIEDE00) foram analisados pelo teste t-Student (p <0,05). Para o estudo 3, foram selecionados 4 voluntários, que tinham LCMB nos dentes anteriores superiores. Os pacientes foram divididos de forma aleatória em dois grupos, sendo estes: ME e IR na área de mancha. Para resolução estética das LCMB, foi determinada a área da mancha em relação a área do dente e a porcentagem da redução pós protocolos. Após 12 meses de acompanhamento, os pacientes receberam clareamento dental, com peróxido de carbamida 10%, durante 21 dias. Os dados do estudo 1 mostram que não houve correlação entre as áreas da mancha (normal e transiluminada) e a resolução estética das mesmas (p>0.05). Em relação a resolutividade, não houve diferença entre os tratamentos (p=0.403). O valor de Luminosidade aumentou após a realização dos procedimentos (p=0.001). Para o estudo 2, nenhuma diferença significativa foi observada no Lab 1 (p=0,560). Para o Lab 2, foram detectadas diferenças significativas (p=0,031). Uma vez que o clareamento foi mais efetivo no grupo não submetido a IR (Lab2). Os resultados do estudo 3 mostram que ambos os protocolos reduziram e/ou suavizaram as áreas das manchas. Após 12 meses de acompanhamento, a técnica de ME apresentou redução no valor da área de mancha. Por fim, o clareamento dental foi efetivo em ambos os protocolos, sem diferenças entre as técnicas. Frente as metodologias propostas, pode-se concluir que: não houve diferenças entre os tratamentos em relação a remoção ou mascaramento das LCMB; a cor das manchas quando transiluminadas não estão relacionadas a resolução estética das mesmas; "in vitro", dentes fortemente manchados, submetidos ao tratamento com RI, o produto parece se comportar como uma barreira semipermeável à penetração do peróxido. Por fim, ambas as técnicas podem ser indicadas para reduzir ou suavizar as áreas de mancha. A ME apresentou redução das áreas de mancha no período avaliado (12 meses). Clinicamente, o clareamento dental pode ser indicado para melhorar a cor dos dentes, independentemente do protocolo pré-estabelecido

The aim of this study was to compare enamel microabrasion (EM) and resin infiltration (RI) techniques in relation to the esthetic resolution of white spot carious lesions (WSL) and to evaluate the correlation between the luminosity of the lesions when transilluminated and the resolution of the problem (study 1); To evaluate in an "in vitro" study, the effectiveness of dental bleaching in samples of teeth previously submitted to RI (study 2); to evaluate the effectiveness of dental bleaching 12 months after the minimal intervention protocols were performed, in a case series study (study 3). For study 1, 17 patients were selected and divided into 2 groups: ME (N=8) and IR (N=9). One tooth from each patient was photographed under normal condition and the same tooth with the aid of a translume device. Then the patients were subjected to the minimal intervention techniques. After 7 days of follow-up, the same photographic protocol was performed. For esthetic resolution, the area of the tooth was delimited in relation to the area of the stain using software. To evaluate the color of the stain when evidenced, the luminosity values (L*) of the coordinates L*a*b* were evaluated before and after the intervention, being measured values of the healthy areas and area of the darker stain. The correlation data were submitted to Person's test. The resolution by the treatments was analyzed by Student's t-test, and the difference in luminosity before and after treatments was analyzed by 2-way repeated measures Anova (p<0.05). For study 2, forty bovine enamel surfaces were subjected to demineralization. Two staining protocols were established. Twenty specimens were immersed in staining broth for 24 hours (Lab 1) or 7 days (Lab 2). Ten specimens from each group received IR application. All specimens were bleached with 15% carbamide peroxide gel for 14 days (8 hours daily). Color measurement was performed by spectrophotometry at three periods: bselien, after staining, and after bleaching. Data (CIEDE00) were analyzed by Student's T test (p <0.05). For study 3, 4 volunteers with WSL in the maxillary teeth were selected. The patients were randomly divided into EM or RI for treating lesions. For esthetic resolution of WSL, the spot area relative to tooth area and the percentage of reduction after protocols were determined. After 12 months of follow-up, the patients received dental bleaching with 10% carbamide peroxide for 21 days. The data from study 1 show that there was no correlation between the stain areas (transilluminated or not) and the esthetic resolution (p>0.05). Regarding resolution, there was no difference between treatments (p=0.403). The Luminosity value increased after the procedures were performed (p=0.001). For study 2, no significant difference was observed in Lab 1 (p=0.560). For Lab 2, significant differences were detected (p=0.031), and whitening was more effective in the group not subjected to IR (Lab2). The results of study 3 show that both protocols reduced and/or softened the areas of the stains. After 12 months of follow-up, the EM technique showed a reduction in the stain area value. Finally, dental bleaching was effective with both protocols, with no differences between the techniques. Based on the proposed methodologies, it can be concluded that: there were no differences between the treatments regarding the removal or masking of WSL; the color of the stains when transilluminated is not related to their esthetic resolution; "in vitro", heavily stained teeth submitted to treatment with RI, the product seems to behave as a semi-permeable barrier to peroxide penetration. Finally, both techniques can be indicated to reduce or soften stained areas. The EM showed a reduction of stained areas in the evaluated period (12 months). Clinically, dental bleaching can be indicated to improve the color of teeth, regardless of the pre-established protocol

Filtración marginal y contracción en la polimerización en nuevas resinas Bulk Fill: una revisión de la literatura / Marginal leakage and polymerization shrinkage in new Bulk Fill resins: a review of the literature

A pesar de los avances e innovaciones de los materiales dentales, la microfiltración marginal y la contracción durante la polimerización continúan siendo una de las causas principales del fracaso de los tratamientos en odontología restauradora. Un sellado marginal correcto será posible cuando las fuerzas de adhesión superen las fuerzas generadas por la contracción de polimerización y las fuerzas generadas por los cambios dimensionales térmicos posteriores a la polimerización, por lo que investigaciones previas demostraron que estas limitaciones pueden ser superadas con el uso de resinas Bulk Fill como material de relleno de cavidades extensas y profundas de dientes posteriores. Estas resinas. de relleno masivo, están recibiendo atención, principalmente porque se pueden colocar, a diferencia de las resinas convencionales, en incrementos de 4 mm sin afectar la contracción de la polimerización, la adaptación de la cavidad o el grado de conversión. El objetivo de la presente revisión bibliográfica es describir la contracción de polimerización y la consecuente filtración marginal que sufren las resinas compuestas para el sector posterior Bulk Fill con base de datos de la literatura (AU)

Despite advances and innovations in dental materials, marginal microfiltration and shrinkage during polymerization continue to be one of the main causes of treatment failure in Restorative Dentistry. A correct marginal seal will be possible when the adhesion forces exceed the forces generated by polymerization contraction and the forces generated by post-polymerization thermal dimensional changes, for which previous research has shown that these limitations can be overcome with the use of Bulk Fill resins as filling material for large and deep posterior tooth cavities, these massive filling resins are receiving attention mainly because they can be placed, unlike conventional resins, in 4 mm increments without affecting polymerization shrinkage. , cavity adaptation or degree of conversion. The objective of the present bibliographic review is to describe the polymerization contraction and consequent marginal filtration suffered by Composite Resins for the Bulk Fill posterior sector with a literature database (AU)

Infiltration by Streptococcus mutans in provisional crowns fixed by two types of cementing agents ­ pilot double-blind randomized clinical trial / Infiltração por Streptococcus mutans em coroas dentárias provisórias fixadas por dois tipos de agentes cimentantes ­ estudo clínico randomizado duplo-cego piloto

Objective: When provisional acrylic crowns are used for a long time, they become more susceptible to marginal leakage by cariogenic bacteria. The objectives of this pilot clinical study were to compare cement based on zinc oxide-eugenol and calcium hydroxide by contamination with Streptococcus mutans, and calculate the sample size for the continuation of this study. Methods: Individuals receiving provisional crowns and following inclusion/exclusion criteria, were randomly distributed into 2 groups: zinc oxide-eugenol (n=8); calcium hydroxide (n=9). The temporary crowns were made by a blind researcher and cemented by another. Patients were also blinded by the cement used inside their crowns. After 2 months, a cement sample from the crowns' peripheral inner face was collected, placed in a tube containing 1 mL of sterile saline, serially diluted, plated on Mitis Salivarius Bacitracin agar, and incubated for 48 hours. Colony-forming units (CFU/mL) were counted. A statistical power analysis was performed to calculate sample size (1-ß=80%) and the Mann Whitney test to compare both cements (α=0.05). Results: Both cements were contaminated with S. mutans, with an average of 166.6 x 102 CFU/mL for calcium hydroxide and 435.3 x 102 CFU/mL for zinc oxide-eugenol, with no significant difference (p=0.311). The sample size calculated for this study was 36 per group. Conclusion: This pilot study suggests that there is important contamination inside provisional crowns used for two months, independent of the cement. The continuation of this study is needed, with a bigger sample size, to enable a comparison between the cements.

Objetivo: Quando coroas dentais provisórias são utilizadas por um longo período, elas se tornam susceptíveis à infiltração marginal por bactérias cariogênicas. O objetivo deste estudo clínico piloto foi comparar os cimentos a base de óxido de zinco e eugenol e hidróxido de cálcio pela contaminação com Streptococcus mutans e calcular o tamanho amostral para continuação deste estudo. Métodos: Indivíduos recebendo coroas provisórias e seguindo critérios de inclusão/exclusão, foram distribuídos aleatoriamente em dois grupos: óxido de zinco e eugenol (n=8); hidróxido de cálcio (n=9). As coroas provisórias foram feitas por um pesquisador cego e cimentadas por outro. Os pacientes também foram cegos quanto ao cimento utilizado dentro de suas coroas. Depois de 2 meses, amostras de cimentos foram coletadas da face interna periférica das coroas, colocadas em um tubo contendo 1 mL de solução salina estéril, diluídas de forma seriada, plaqueadas em ágar Mitis Salivarius Bacitracina e incubadas por 48 horas. Unidades formadoras de colônias (UFC/mL) foram contadas. Um teste de poder estatístico foi realizado para calcular o tamanho amostral (1-ß=80%) e o teste de Mann Whitney para comparar os dois cimentos (α=0.05). Resultados: Os dois cimentos foram contaminados com S. mutans, com uma média de 166.6 x 102 UFC/mL para o hidróxido de cálcio e 435.3 x 102 UFC/mL para o óxido de zinco e eugenol, com nenhuma diferença significativa (p=0.311). O cálculo amostral para este estudo foi 36 indivíduos por grupo. Conclusão: Este estudo piloto sugere que existe importante contaminação dentro de coroas provisórias utilizadas por 2 meses, independente do cimento. A continuação deste estudo é necessária, com maior tamanho amostral, para possibilitar a comparação entre os cimentos.

Estudio in vitro de la relación entre resistencia de unión a esmalte dental y microfiltración en resinas compuestas fotopolimerizables / In vitro study of the relationship between bond strength to dental enamel and microleakage in photopolymerizable composite resins

Objetivos. Evaluar y comparar la relación entre la resistencia de unión inmediata a esmalte y microfiltración de dos sistemas restauradores a base de resina compuesta. Métodos. 40 terceros molares se dividieron aleatoriamente en dos grupos: 20 molares restaurados utilizando el sistema Adper Single bond 2 + Filtek Z250 XT (3M ESPE; ST PAUL, MN, USA); y 20 molares restaurados con el sistema Tetric N Bond + Tetric N Ceram (Ivoclar Vivadent; Schaan, Liechtenstein). La mitad de los dientes de cada grupo se utilizaron para un ensayo de microtracción, mientras que la otra mitad fueron utilizados para un ensayo de microfiltración (n = 10). Resultados. Las medias y el desvío padrón de la resistencia de unión a microtracción fueron de 27.93 (±9.55) para Adper Single bond 2 + Filtek Z250 XT MPa y 33.12 (±8.18) MPa para Tetric N Bond + Tetric N Ceram (p = 0,049). En cuanto a los valores de microfiltración, no hubo diferencias estadísticamente significativas entre los grupos (p = 0,478). No fue observada una correlación significativa entre la resistencia de unión a la microtracción y la microfiltración (R2 = 0.0909; p = 0.196). Conclusiones. No se encontró una relación entre los valores de resistencia de unión y el grado de microfiltración.

Objectives. To evaluate and compare the relationship between enamel bond strength and microleakage of two composite based restorative systems. Methods. 40 third molars were randomly divided into two groups: 20 molars restored with the Adper Single bond 2 + Filtek Z250 XT (3M ESPE; ST PAUL, MN, USA) system and 20 with the Tetric N Bond + Tetric N Ceram (Ivoclar Vivadent; Schaan, Liechtenstein) system. "Half of the teeth" in each group were subjected to a bond strength test, while the others were subjected to the microleakage test. Results. The means and standard deviation of the bond strength resistance were 27.93 (± 9.55) MPa for Adper Single bond 2 + Filtek Z250 XT system and 33.12 (± 8.18) MPa for Tetric N Bond + Tetric N Ceram system (p = 0.049). Regarding microleakage values, there were no statistically significant differences between the groups (p = 0.478). No significant correlation was observed between microtensile bond strength and microleakage (R2 = 0.0909, p = 0.196). Conclusions. No relationship was found between adhesive bond values and degree of microleakage.

Objetivos. Avaliar e comparar a relação entre a resistência de união imediata ao esmalte e a microfiltração de dois sistemas restauradores baseados em resina composta. Métodos. 40 terceiros molares foram divididos aleatoriamente em dois grupos: 20 molares restaurados usando o sistema Adper Single bond 2 + Filtek Z250 XT (3M ESPE; ST PAUL, MN, EUA); e 20 molares restaurados com o sistema Tetric N Bond + Tetric N Ceram (Ivoclar Vivadent; Schaan, Liechtenstein). Metade dos dentes de cada grupo foi utilizada para um teste de resistência de união à microtração, enquanto a outra metade foi utilizada para um teste de microfiltração (n = 10). Resultados. As mídias e o padrão de resistência de união à microtração foram 27,93 (± 9,55) para Adper Single bond 2 + Filtek Z250 XT MPa e 33,12 (± 8,18) MPa para Tetric N Bond + Tetric N Ceram (p = 0,049). Em relação aos valores de microfiltração, não houve diferença estatisticamente significativas entre os grupos (p = 0,478). Não houve correlação significativa observada entre a resistência de união à microtração e a microfiltração (R2 = 0,0909; p = 0,196). Conclusões. Não foi encontrada relação entre os valores de resistência de união e o grau de microfiltração.