Presence of Voids after Continuous Wave of Condensation and Single-cone Obturation in Mandibular Molars: A Micro-computed Tomography Analysis.

INTRODUCTION: The objective of this study was to assess the presence of voids in mesial root canals of mandibular molar teeth obturated by using the single-cone (SC) and continuous wave of condensation (CWC) obturation techniques, and results were analyzed by using micro-computed tomography. METHODS: Twenty-four mandibular molars with fully developed roots and mesial root curvature ranging from 25° to 35° were instrumented by using Reciproc R25 files, and then they were obturated by using the SC and CWC techniques. Specimens were scanned before and after obturation for micro-computed tomography analysis (voxel size, 17.42 µm). After volumetric analysis and tridimensional reconstruction of the root canals, data were analyzed by using analysis of variance and the Tukey test. RESULTS: No significant differences were observed between the 2 techniques in terms of total percentage volume of voids: CWC = 3.91% ± 0.72%; SC = 6.52% ± 1.16% (P > .05). Only in the cervical third, CWC showed a significantly lower percentage of voids when compared with SC, namely 2.86% ± 0.94% vs 8.00% ± 1.86%, respectively (P < .05). CONCLUSIONS: The percentage volume of voids was similar in the 2 groups and was influenced by the obturation technique only in the cervical third.

Ozone therapy as an adjuvant for endondontic protocols: microbiological – ex vivo study and citotoxicity analyses

ABSTRACT Objectives This study evaluated the antimicrobial efficacy of ozone therapy in teeth contaminated with Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus using a mono-species biofilm model. Parallel to this, the study aimed to evaluate the cytotoxicity of ozone for human gingival fibroblasts. Material and Methods: One hundred and eighty single-root teeth were contaminated with a mono-species biofilm of Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus. Groups were formed: Group I – control; Group II – standard protocol; Group III – standard protocol + ozone gas at 40 µg/mL; and Group IV – standard protocol + aqueous ozone at 8 µg/mL. In parallel, human gingival fibroblasts were submitted to the MTT test. Cells were plated, then ozone was applied as follows: Group I (control) – broth medium; Group II – aqueous ozone at 2 µg/mL; Group III – aqueous ozone at 5 µg/mL; and Group IV – aqueous ozone at 8 µg/mL. Data were submitted to the Kruskal Wallis test and Bonferroni post hoc analyses to assess microbiology and cytotoxicity, respectively (p<0.05%). Results The results revealed antimicrobial efficacy by Group IV with no CFU count. The cytotoxicity assay showed Groups III and IV to be the most aggressive, providing a decrease in cell viability at hour 0 from 100% to 77.3% and 68.6%, respectively. Such a decrease in cell viability was reverted, and after 72 hours Groups III and IV provided the greatest increase in cell viability, being statistically different from Groups I and II. Conclusion According to the applied methodology and the limitations of this study, it was possible to conclude that ozone therapy improved the decontamination of the root canal ex vivo. Ozone was toxic to the cells on first contact, but cell viability was recovered. Thus, these findings suggest that ozone might be useful to improve root canal results.

Ozone therapy as an adjuvant for endondontic protocols: microbiological - ex vivo study and citotoxicity analyses.

OBJECTIVES: This study evaluated the antimicrobial efficacy of ozone therapy in teeth contaminated with Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus using a mono-species biofilm model. Parallel to this, the study aimed to evaluate the cytotoxicity of ozone for human gingival fibroblasts. Material and Methods: One hundred and eighty single-root teeth were contaminated with a mono-species biofilm of Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus. Groups were formed: Group I - control; Group II - standard protocol; Group III - standard protocol + ozone gas at 40 µg/mL; and Group IV - standard protocol + aqueous ozone at 8 µg/mL. In parallel, human gingival fibroblasts were submitted to the MTT test. Cells were plated, then ozone was applied as follows: Group I (control) - broth medium; Group II - aqueous ozone at 2 µg/mL; Group III - aqueous ozone at 5 µg/mL; and Group IV - aqueous ozone at 8 µg/mL. Data were submitted to the Kruskal Wallis test and Bonferroni post hoc analyses to assess microbiology and cytotoxicity, respectively (p<0.05%). RESULTS: The results revealed antimicrobial efficacy by Group IV with no CFU count. The cytotoxicity assay showed Groups III and IV to be the most aggressive, providing a decrease in cell viability at hour 0 from 100% to 77.3% and 68.6%, respectively. Such a decrease in cell viability was reverted, and after 72 hours Groups III and IV provided the greatest increase in cell viability, being statistically different from Groups I and II. CONCLUSION: According to the applied methodology and the limitations of this study, it was possible to conclude that ozone therapy improved the decontamination of the root canal ex vivo. Ozone was toxic to the cells on first contact, but cell viability was recovered. Thus, these findings suggest that ozone might be useful to improve root canal results.

Histological analysis of the biocompatibility of calcium hydroxide associated with a new vehicle.

BACKGROUND: Several substances have been researched to act as vehicles associated with calcium hydroxide. The specific type of vehicle is directly related to the effectiveness of the ionic dissociation, antimicrobial action, and biocompatibility of this medication. AIM: To make a histological evaluation of the biocompatibility of calcium hydroxide associated with a new vehicle (triethanolamine), compared with polyethylene glycol, saline solution, and olive oil. MATERIALS AND METHODS: Fifty mice of guinea pig species were randomly divided into five groups (n = 10) according to each vehicle used--Group 1: calcium hydroxide, Group 2: triethanolamine, Group 3: polyethylene glycol, Group 4: saline solution, and Group 5: olive oil--and further divided into subgroups according to the two analysis periods--(a) 30 and (b) 90 days. Teflon carriers filled with the evaluated substances were placed in standardized bone cavities in the anterior mandible region. The animals were euthanized to perform a histological analysis after the time periods analyzed. RESULTS: In 30 days, specimens from Groups 1, 3, and 5 showed a very pronounced inflammatory response. Specimens from Group 2 showed an inflammatory reaction ranging from mild to severe, with rapid resorption of the material and progressive advancement of osteoid tissue into the teflon carriers. Specimens from Group 4 showed a moderate inflammatory reaction. In 90 days, specimens from Group 1 showed a very pronounced fibrous replacement. In regard to Group 2 specimens, the tested material was solubilized and replaced by newly formed bone tissue. For Groups 3 and 5 specimens, the inflammatory reaction went from acute to moderate. In relation to Group 4 specimens, an organized bone formation process was observed. CONCLUSIONS: Specimens from Group 2 showed higher biocompatibility, especially as compared with the specimens from Groups 3 and 5.

Teleodontologia no processo de divulgação e implementação de Bancos de Dentes Humanos / Teleodontology in the process of dissemination and implementation of Human Teeth Banks

Na era da colaboração, surge o Ensino a Distância (EaD) como poderosa ferramenta de divulgação de realidades, permitindo que a importância do BDH seja divulgada adequadamente. Diversas iniciativas estão sendotomadas de modo articulado, a fim de facilitar a criação e a consolidação de uma rede de colaborativa detrabalho em Telessaúde e Teleodontologia para a divulgação e implementação de Bancos de Dentes Humanosem sua faculdade ou centro de pesquisasbaseado no caminho trilhado pela Faculdade de Odontologia da USP (AU).

In the era of collaboration, arises Distance Education (DE) as a powerful tool for the dissemination of realities, allowing the importance of BDH is disclosed properly. Several initiatives are being taken in an articulate manner in order to facilitate the creation and consolidation of a network of collaborative working in Telehealth and Teledentistry for the dissemination and implementation of Banks Human Teeth at your college or research center based on the path followed by School of Dentistry, USP (AU).

Núcleo de Teleodontologia da Faculdade de Odontologia da Universidade de São Paulo: uma melhor educação para uma melhor saúde em tempos de TIC / The Teledentistry Center of the Dental School of the University of São Paulo: better education for a better health in times of ICT

O Núcleo de Teleodontologia da Faculdade de Odontologia da Universidade de São Paulo (NTO-FOUSP) foi criado em articulação com o Núcleo São Paulo de Telessaúde, como parte do Programa Telessaúde Brasil, pelo Ministério da Saúde. Seu foco: dar suporte aos professores para uso das TIC. Também deverá oferecer teleconsultorias e Segundas Opiniões Formativas aos profissionais de saúde do Sistema Único de Saúde (SUS).

The Teledentistry Center at the Faculty of Dentistry (NTO-FOUSP), University of São Paulo, was created in articulation with the Center of Telehealth of São Paulo, as part of the Brazilian Telehealth Program, by the Ministry of Health. Its first aim was to offer support to the professors for a better use of ICT. It should also offer teleconsulting and the Second Formative Opinion for health professionals working at the Unified Health System (SUS).

Teleodontologia: valores agregados para o clínico/especialista / Teledentistry: oggregote volues for the clinicion/speciolist

A ciência inovadora da Teleodontologia oferece conhecimento odontológico em dois âmbitos principais: a teleassistência e a teleducação. Em se tratando de inovações tecnológicas trazidas pelas Novas Tecnologias de Informação e Comunicação (NTICl, é possível recorrer a esses conhecimentos para aplicação em diversos âmbitos da vida profissional, como uma nova visão de clínica interdisciplinar ou maneiras criativas de se aplicar o marketing profissional. O texto ainda retrata os cuidados devidos à manutenção do sigilo das informações relativas aos pacientes e formas seguras e criativas de se incorporar as NTIC no dia a dia do Cirurgião-Dentista, acrescentando valor à ação profissional e qualificação na atenção à saúde bucal brasileira.

The innovative science of Teledentistry offers dental knowledge in two main areas: the teleducation and teleassistance. Technological innovations brought by the New Information and Communication Technologies (lCTs) offers this knowledge for application in various areas of professional life, as a new vision of interdisciplinary clinical and creative ways to apply in the marketing professional. The text also explores the care of the confidentiality maintenance of information relating to patients and safe and creative ways to incorporate ICT in the dentist day-by-day, adding value to the professional action and qualifying the oral health care in Brazil..

Influence of final rinse technique on ability of ethylenediaminetetraacetic acid of removing smear layer.

INTRODUCTION: There is ongoing debate regarding the ideal sequence, volume, and concentration of irrigants, length of time for irrigation, and irrigation technique to achieve debridement of the root canal system. The aim of this study was to verify the impact of the final rinse technique on smear layer removal ability of 17% ethylenediaminetetraacetic acid (EDTA). METHODS: Sixteen single-rooted human teeth were instrumented and divided into 2 groups at the final rinse step according to the following final rinse techniques used: continuous rinse group, continuous rinse with EDTA during 3 minutes, and rinse and soaking group, rinse with 1 mL of EDTA, soaking of the canal for 2 minutes and 30 seconds, and rinse completion with the remaining 4 mL for 30 seconds. The specimens were split lengthwise and observed under scanning electron microscope. RESULTS: Data were analyzed with Kruskal-Wallis and Dunn tests. The continuous rinse group presented more debris-free surfaces when compared with the rinse and soaking group (P<.01). When the root canal areas were compared within the groups, no statistical differences were found (P>.05). CONCLUSIONS: It can be concluded that a continuous rinse with 5 mL of EDTA for 3 minutes can more efficiently remove the smear layer from root canal walls.

Does a final rinse to remove smear layer interfere on dentin permeability of root canals?

OBJECTIVE: The objective of this study was to assess the influence of different final irrigating solutions on dentin permeability and smear layer removal using the same specimens and relate the results obtained. STUDY DESIGN: Forty anterior human teeth were instrumented and divided into 4 groups (n = 10) at the final rinse step, according to the irrigant used: G I (control) - 1% NaOCl; G II - 17% EDTA; G III - 17% EDTAT; and G IV - Biopure MTAD. The canals were filled with 0.5% methylene blue and maintained in bottles for 48 hours. The roots were transversally split in coronal, middle, and apical fragments. The specimens were photographed and analyzed regarding dye penetration. The fragments were then axially split and prepared for SEM. The photomicrographs were analyzed and qualified by scores. RESULTS: Only the EDTA-T group exhibited statistical difference in which the apical third had less dentin permeability (P < .05). When a decalcifying agent was used, smear layer was removed, which did not happen in the NaOCl group. Regarding smear layer removal, differences were found only in the EDTA group in which the apical third presented more smear layer (P < .05). No correlation was found for both studies (r = 0.4207). CONCLUSIONS: There was not an even relationship between the results from both studies, which inferes that higher or lower dentinal permeability does not necessarily correspond to a higher or lower amount of smear layer. The analysis of dentin permeability and smear layer removal was shown to be a feasible procedure using the same specimens.

Coronal and apical leakage analysis of two different root canal obturation systems.

This study compared the coronal and apical leakage of AH Plus with gutta-percha to that of Epiphany with Resilon. Twenty-four single rooted teeth were instrumented and divided into 2 groups according to the solutions for smear layer removal and the obturation materials employed: Group A - 17% EDTA-T and AH Plus with gutta-percha; Group B - primer and Epiphany with Resilon. The Group B specimens were light-cured in the coronal area for 20 s. The external root surfaces were covered with a double layer of ethyl cyanoacrylate, except for the apical foramen and the cavity access. The teeth were immersed in 0.5% methylene blue for 48 h. The specimens were rinsed, dried and axially split for dye penetration measurement with the ImageLab 2.3 software. The t-test showed no significant differences for coronal leakage between the groups, but there were significant differences for apical leakage between the groups (P < 0.05). AH Plus with gutta-percha and Epiphany with Resilon provided the same coronal seal, whereas Epiphany with Resilon provided the best apical seal.

Influence of different volumes of EDTA for final rinse on smear layer removal.

OBJECTIVE: The aim of this study was to analyze the influence of different volumes of 17% EDTA for final rinse on smear layer removal on the different areas of the root canal. STUDY DESIGN: Forty single-rooted teeth were instrumented using rotary instruments. The teeth were divided into 3 test groups according to the EDTA volume for final rinse (5 mL, 10 mL, 15 mL) and 1 control group (10 mL of 1% sodium hypochlorite). The roots were axially split into halves, and the smear layer removal from the canals was determined under scanning electron microscope. The data were analyzed using Kruskal Wallis and Dunn tests. RESULTS: The 3 experimental groups showed no statistical difference (P > .05); however, when the test groups were compared to the control group statistically significant differences were found (P < .01). The root canal wall surfaces of teeth in the control group showed the presence of heavy smear layer through the entire length of the root canals. The other groups showed mainly smear layer-free surfaces or a small amount of debris. When coronal, middle and apical thirds were compared, there was no statistically significant difference (P > .05). CONCLUSIONS: Based on the results, it appears that a final rinse with 5 mL of EDTA per canal provides good smear layer removal, with root canal walls free of debris and mostly open dentinal tubules in all areas.

Coronal and apical leakage analysis of two different root canal obturation systems

This study compared the coronal and apical leakage of AH Plus with gutta-percha to that of Epiphany with Resilon. Twenty-four single rooted teeth were instrumented and divided into 2 groups according to the solutions for smear layer removal and the obturation materials employed: Group A - 17 percent EDTA-T and AH Plus with gutta-percha; Group B - primer and Epiphany with Resilon. The Group B specimens were light-cured in the coronal area for 20 s. The external root surfaces were covered with a double layer of ethyl cyanoacrylate, except for the apical foramen and the cavity access. The teeth were immersed in 0.5 percent methylene blue for 48 h. The specimens were rinsed, dried and axially split for dye penetration measurement with the ImageLab 2.3 software. The t-test showed no significant differences for coronal leakage between the groups, but there were significant differences for apical leakage between the groups (P < 0.05). AH Plus with gutta-percha and Epiphany with Resilon provided the same coronal seal, whereas Epiphany with Resilon provided the best apical seal.

Influence of Nd:YAG and diode laser irradiation on apical sealing when associated with AH plus and EndoREZ endodontic cements.

OBJECTIVE: This study aims to evaluate the influence of Nd:YAG and diode laser irradiation on apical sealing when applied before root canal filling done with two different resin-based cements (AH Plus and EndoREZ). BACKGROUND DATA: Lasers have been widely used in endodontics. The morphologic changes in dentin walls caused by Nd:YAG and diode laser irradiation could improve sealing ability of endodontic cements. METHODS: Eighty canine teeth were analyzed by apical leakage of methylene blue dye and by scanning electron microscope (SEM) images of the filling's adaptation to the apical third dentin walls. The laser irradiation parameters for the Nd:YAG laser were 100 mJ, 15 Hz, and 1.5 W, and for the diode laser was 2.5 W (continuous mode). RESULTS: The apical leakage results showed statistically significant differences at the 5% level of significance (Tukey's test, p < 0.05) among the different root canal wall treatments, independently of the root canal filling cement used. The cements also showed significant differences between them on the lased groups. The SEM analysis revealed better filling adaptation for AH Plus and the Nd:YAG laser group, confirming the microleakage results. CONCLUSION: We concluded that the combination of the Nd:YAG laser and AH Plus showed the best results.

Infecções periapicais agudas com envolvimento sistêmico - preparo químico-cirúrgico de canais radiculares associados ao uso sistêmico da azitromicina (avaliação clínica, microbiológica e tolerabilidade) / Acute periapicais infections with systemic envolvement - chemistry-surgical preparation of root canals associated to the systemic use of the azithromycin (clinical, microbiological evaluation and tolerance)

Introdução - O objetivo deste estudo foi determinar a eficácia clínica, microbiológica e a tolerabilidade de uma dose única diária de 500mg de azitromicina por 3 dias (Zitromax - Pfizer) associada ao preparo químico-cirúrgico em 38 pacientes do Setor de Urgência da Faculdade de Odontologia da Universidade de São Paulo com infecção periapical aguda e antibioticoterapia indicada. Material e Métodos - Os sinais e sintomas da infecção e os exames microbiológicos foram avaliados antes da administração da azitromicina na 1ª consulta (preparo químico-cirúrgico sumário e medicação intracanal), na 2ª consulta, entre o 3º e 5º dia (preparo químico-cirúrgico completo e medicação intracanal) e na 3ª consulta, entre o 8º e 12º dia (obturação do canal). As coletas para os testes microbiológicos foram submetidas a cultivo em tioglicolato de sódio, a uma primeira bacterioscopia, a subcultivo em ágar-sangue de carneiro a 5% e a uma segunda bacterioscopia. Resultados - O desaparecimento total dos sinais e sintomas da infecção deu-se em 93% dos pacientes, parcial em 5,0% e permanência em 2%. Dos 9 pacientes submetidos ao exame microbiológico, aproximadamente 67% apresentaram erradicação completa dos microrganismos na 2ª consulta, 2% na 3ª e persistência de Streptococcus mitis em 11%. Os efeitos adversos da medicação foram dor abdominal em aproximadamente 16% dos pacientes, taquicardia em 5% e diarréia em 5%, todos de intensidade leve a moderada e sem necessidade de interrupção do tratamento. Conclusão - O esquema terapêutico local associado ao uso sistêmico da azitromicina é eficaz e de boa tolerabilidade no tratamento de infecções periapicais agudas com antibioticoterapia indicada, e portanto, a azitromicina é uma boa alternativa para pacientes alérgicos às penicilinas

Avaliação da difusão térmica na dentina e cemento radicular quando da utilização in vitro do Endox® / Evaluation of thermal diffusion on radicular dentin and cementum utilizing Endox® in vitro

O propósito deste estudo foi avaliar a difusão da temperatura desenvolvida na parede dentinária de raízes pelo uso de um aparelho eletrônico denominado Endox®. Trata-se de um sistema para tratamento endodôntico digital de eletrofulguração com duas finalidades: localização apical e desinfecção do canal radicular por meio de corrente elétrica de alta freqüência e intensidade durante 1/10 de segundo, que resulta na vaporização de seu conteúdo. Foram utilizados 40 caninos com ápices afilados e arredondados, subdivididos em 20 de cada, variando a intensidade da radiofreqüência, 600 kHz padrão e aumento de 20%, 720 kHz, aplicados nos terços cervical, médio, apical e ápice da raiz e medida a temperatura com termômetro digital. Os resultados obtidos foram submetidos à análise de variância ANOVA e ao teste de Tukey (p=0,05). A diferença de temperatura entre as duas raízes afiladas e arredondadas foi de aproximadamente 1°C. Entre os terços radiculares, houve aumento progressivo de cervical para o ápice, com diferenças significantes estatisticamente entre as médias da temperatura, independentemente do formato das raízes e radiofreqüência. A diferença entre as temperaturas iniciais e finais não gerou calor excessivo na superfície radicular. A estatística é significante nas médias das diferenças de temperatura, nas interações de terços, formatos radiculares e intensidades, entre ápice e terço médio. Nas afiladas com aumento de freqüência, houve diferença entre todos os seus terços. No experimento in vitro, o aumento de temperatura variou, em média, 10°C, independentemente do formato radicular e intensidade de freqüência, o que é tolerável para a reparação óssea. É recomendado utilizar a intensidade de freqüência padrão para melhor controle da temperatura em níveis baixos.

Effects of diode laser (810 nm) irradiation on root canal walls: thermographic and morphological studies.

This study investigated the thermal effects and the morphological changes after diode laser irradiation (810 nm) of root canals. Samples were irradiated at 2.5 W, 1,989 W/cm2 (group 2) and 1.25 W, 10 Hz, 994 W/cm2 (group 3), with group 1 being the control group of nonirradiated samples. The temperature rise was evaluated using an infrared thermographic camera, and the morphological changes were assayed by scanning electron microscopy (SEM). The SEM images revealed closed dentinal tubules, especially at the apical regions when compared with the control samples. The maximum temperature variations at the apical region were analyzed, and the resulting 95% confidence intervals of the medians (Wilcoxon) ranged from 1.6 to 8.6 degrees C (group 2) and from 1.2 to 3.3 degrees C (group 3). The results suggest that the diode laser can be used for endodontic purposes and show that the method is safe for periodontal tissues at the investigated parameters.

Análise pela microscopia eletrônica de varredura da remoção de hidróxido de cálcio P.A. como medicação intracanal segundo diferentes técnicas / Scanning electron microscope analysis of P. A calcium hydroxide removal as intracanal medication by diferent techniques

Foi objetivo avaliar a remoção do hidróxido de cálcio P.A, veiculado ao polietilenoglicol 400 quando utilizado como medicação intrancal. Foram utilizados 34 pré-molares inferiores com canal único divididos em 3 grupos. No grupo 1, a medicação foi removida na presença de líquido de Dakin; no grupo 2, acrescentou-se EDTA-T como solução irrigadora final e no grupo 3 utilizou-se creme de Endo-PTC juntamente ao líquido de Dakin durante a reinstruturação e EDTA-T como solução irrigadora final. Após a remoção da medicação, os dentes foram clivados para análise pela microscopia eletrônica de varredura. Os dentes foram avaliados nos terços cervical, médio e apical quantitativamente quanto ao número de túbulos dentinários livres de resíduos por três observadores. Os dados obtidos foram submetidos ao teste estatístico com nível de signficância 5 porcento. Os resultados mostraram que a limpeza do grupo 3 é diferente e melhor do que o grupo 1, não sendo as outras combinações diferentes entre si. Entre os terços, a melhor capacidade de limpeza final ocorreu no terço cervical do grupo 3.