Abstract Objectives This study aimed to investigate patterns and risk factors related to the feasibility of achieving technical quality and periapical healing in root canal non-surgical retreatment, using regression and data mining methods. Methodology This retrospective observational study included 321 consecutive patients presenting for root canal retreatment. Patients were treated by graduate students, following standard protocols. Data on medical history, diagnosis, treatment, and follow-up visits variables were collected from physical records and periapical radiographs and transferred to an electronic chart database. Basic statistics were tabulated, and univariate and multivariate analytical methods were used to identify risk factors for technical quality and periapical healing. Decision trees were generated to predict technical quality and periapical healing patterns using the J48 algorithm in the Weka software. Results Technical outcome was satisfactory in 65.20%, and we observed periapical healing in 80.50% of the cases. Several factors were related to technical quality, including severity of root curvature and altered root canal morphology (p<0.05). Follow-up periods had a mean of 4.05 years. Periapical lesion area, tooth type, and apical resorption proved to be significantly associated with retreatment failure (p<0.05). Data mining analysis suggested that apical root resorption might prevent satisfactory technical outcomes even in teeth with straight root canals. Also, large periapical lesions and poor root filling quality in primary endodontic treatment might be related to healing failure. Conclusion Frequent patterns and factors affecting technical outcomes of endodontic retreatment included root canal morphological features and its alterations resulting from primary endodontic treatment. Healing outcomes were mainly associated with the extent of apical periodontitis pathological damages in dental and periapical tissues. To determine treatment predictability, we suggest patterns including clinical and radiographic features of apical periodontitis and technical quality of primary endodontic treatment.
Abstract Satisfactory biological behavior is a necessary requirement for clinical application of endodontic materials. In this study, the connective tissue responses to silicone (GuttaFlow 2), epoxy resin (AH Plus) and zinc oxide and eugenol (Endofill) based sealers were compared. Twelve Wistar rats had polyethylene tubes (four per animal) containing one of the tested sealers and empty tubes (negative control) implanted in their subcutaneous tissue. The tubes were randomly placed 2 cm from the spine and at least 2 cm apart from one another. Tissue samples with implants were processed for histological analysis after 7 or 60 days (n=6 animals per period). Inflammatory cells, fibrous condensation and abscess were scored according to their intensity. Friedman, followed by Dunn's post hoc, was used to compare sealers. Differences between the two experimental periods were verified using Mann-Witney U test (p<0.05). At 7 days, most of the histological parameters showed no significant differences amongst groups. Endofill group scored higher than the others for giant cells (o<0.05) and promoted a greater number of samples presenting abscess formation. GuttaFlow 2 tended to show a less intense inflammatory infiltrate compared to the other materials. At 60 days, there were no significant differences between groups in most of the histological parameters evaluated. However, it was observed that Endofill scored higher for macrophages (p<0.05) compared to the control group, and GuttaFlow 2 tended to present lower scores than the others for neutrophils and abscess. GuttaFlow 2 showed proper biological behavior and should be considered adequate for clinical practice.
Resumo Um dos requisistos para a aplicação clínica de materiais endodônticos é apresentar comportamento biológico satisfatório. Neste estudo, as respostas do tecido conjuntivo a cimentos endodônticos à base de silicone (GuttaFlow 2), resina epóxica (AH Plus) e óxido de zinco e eugenol (Endofill) foram comparadas. Doze ratos Wistar tiveram tubos de polietileno (4 em cada animal) contendo um dos materiais e tubos vazios (controle negativo) implantados no tecido conjuntivo subcutâneo. Os tubos foram randomicamente posicionados pelo menos 2 cm distantes entre si e da espinha dorsal do animal. Amostras de tecido contendo os implantes foram processadas para análise histológica após 7 e 60 dias (n=6 animais por período). Células inflamatórias, condensação fibrosa e formação de abscesso foram classificadas em escores de acordo com sua intensidade. O teste Friedman, seguido por post hoc de Dunn, foi empregado para comparar os cimentos. O teste de Mann-Witney U foi empregado para verificar diferenças entre os períodos experimentais em cada grupo (p<0,05). Após 7 dias, a maior parte dos parâmetros histológicos não mostrou diferenças estatísticas entre os grupos. O cimento Endofill promoveu escores mais altos que os outros materiais para a variável células gigantes (p<0,05), além de apresentar um maior número de amostras com formação de abscesso. O GuttaFlow 2 tendeu a apresentar infiltrado inflamatório menos intenso comparado aos outros materiais. Após 60 dias, não houve diferenças estatisticamente significantes entre os grupos na maioria dos parâmetros avaliados. Entretanto, observou-se que o EndoFill apresentou escores mais altos para os macrófagos em comparação ao controle (p<0,05) e que o GuttaFlow 2 apresentou tendência a escores mais baixos que os demais materiais para as variáveis neutrófilos e abscesso. O GuttaFlow 2 apresentou propriedades biológicas apropriadas e pode ser considerado adequado para a prática clínica.
Abstract The aim of this study was to evaluate whether the modification in the silver component is capable of providing GuttaFlow 2 with antibacterial activity against Enterococcus faecalis compared with epoxy resin-based (AH Plus) and zinc oxide and eugenol-based (Endofill) sealers. The antibacterial activity was evaluated using a reference strain of E. faecalis (ATCC 29212). Freshly mixed sealers were subjected to the agar diffusion test (ADT), while the direct contact test (DCT) was performed after materials setting. ADT results were obtained through measurements, in millimeters, of the inhibition zones promoted by the materials, using a digital caliper. In DCT, values of CFU/mL promoted by the three sealers were compared in three experimental periods (1 min, 1 h, and 24 h). The data were analyzed using Kruskal-Wallis and Dunn post-hoc tests (p < 0.05). In both ADT and DCT, GuttaFlow 2 presented no effect against E. faecalis, while Endofill and AH Plus showed similar inhibition zones. Endofill was the only material capable of reducing bacterial growth in DCT. In conclusion, modifications in the silver particle of GuttaFlow 2 did not result in a sealer with antibacterial effect against E. faecalis.
Abstract The present study aims to verify the effect of ozone gas (OZY® System) and high frequency electric pulse (Endox® System) systems on human root canals previously contaminated with Escherichia colilipopolysaccharide (LPS). Fifty single-rooted teeth had their dental crowns removed and root lengths standardized to 16 mm. The root canals were prepared up to #60 hand K-files and sterilized using gamma radiation with cobalt 60. The specimens were divided into the following five groups (n = 10) based on the disinfection protocol used: OZY® System, one 120-second-pulse (OZY 1p); OZY® System, four 24-second-pulses (OZY 4p); and Endox® System (ENDOX). Contaminated and non-contaminated canals were exposed only to apyrogenic water and used as positive (C+) and negative (C-) controls, respectively. LPS (O55:B55) was administered in all root canals except those belonging to group C-. After performing disinfection, LPS samples were collected from the canals using apyrogenic paper tips. Limulus Amoebocyte Lysate (LAL) was used to quantify the LPS levels, and the data obtained was analyzed using one-way ANOVA. The disinfection protocols used were unable to reduce the LPS levels significantly (p = 0.019). The use of ozone gas and high frequency electric pulses was not effective in eliminating LPS from the root canals.
AbstractThe presence of endotoxin inside the root canal has been associated with periapical inflammation, bone resorption and symptomatic conditions.Objectives To determine, in vitro, the effect of QMix® and other three root canal irrigants in reducing the endotoxin content in root canals.Material and Methods Root canals of single-rooted teeth were prepared. Samples were detoxified with Co-60 irradiation and inoculated with E. coli LPS (24 h, at 37°C). After that period, samples were divided into 4 groups, according to the irrigation solution tested: QMix®, 17% EDTA, 2% chlorhexidine solution (CHX), and 3% sodium hypochlorite (NaOCl). LPS quantification was determined by Limulus Amebocyte Lysate (LAL) assay. The initial counting of endotoxins for all samples, and the determination of LPS levels in non-contaminated teeth and in contaminated teeth exposed only to non-pyrogenic water, were used as controls.Results QMix® reduced LPS levels, with a median value of 1.11 endotoxins units (EU)/mL (p<0.001). NaOCl (25.50 EU/mL), chlorhexidine (44.10 EU/mL) and positive control group (26.80 EU/mL) samples had similar results. Higher levels were found with EDTA (176.00 EU/mL) when compared to positive control (p<0.001). There was no significant difference among EDTA, NaOCl and CHX groups. Negative control group (0.005 EU/mL) had statistically significant lower levels of endotoxins when compared to all test groups (p<0.001).Conclusion QMix® decreased LPS levels when compared to the other groups (p<0.001). 3% NaOCl, 2% CHX and 17% EDTA were not able to significantly reduce the root canal endotoxins load.
The present study aimed to determine the feasibility of using bovine teeth as a suitable alternative for human teeth, in experiments involving in vitro endotoxin contamination. Twenty bovine central incisors and 20 human single-root premolars had their dental crowns removed and root lengths set at 16 mm. Root canals were prepared up to #60 K-file size and sterilized with cobalt-60 gamma irradiation (20 kGy, 6 h). The teeth were randomly divided into four groups: G1-bovine teeth (bovine negative control, n = 10), G2-human teeth (human negative control, n = 10), G3-bovine teeth, inoculated withEscherichia coli (055:B55) LPS, and G4-human teeth inoculated with E. coli LPS. The G1 and G2 groups were exposed to apyrogenic water. After the teeth had been incubated at 37 °C and atmospheric humidity for 24 h, the samples of solutions in the main canals were collected with apyrogenic absorbent paper tips. LPS levels were quantified using Limulus Amebocyte Lysate assay. The data obtained were statistically analyzed using one-way ANOVA, with a significance level of 5%. A high amount of endotoxin was detected in the inoculated human teeth (G4) when compared to the sterilized teeth (G2), as well as in the inoculated bovine teeth (G3) when compared to the inoculated human teeth (G4). However, there was no statistical difference between bovine teeth before and after the E. coli endotoxin inoculation. Therefore, under the mentioned experimental conditions, the use of bovine teeth should not be a choice for laboratory research on endotoxin contamination.
Dens invaginatus is a well-known malformation of teeth, which probably results from an invagination of enamel organ into dental papilla during tooth development. The endodontic treatment of invaginated teeth may be challenging due to difficulties in accessing the root canals and also due to complex variations of internal morphology. This article presents the endodontic management and follow-up in a rare case of right mandibular second premolar with Oehlers' type III dens invaginatus. The result of cold pulp testing was positive for this tooth but it was associated to a sinus tract and periapical lesion. Herein, it is described the root canal therapy of this tooth combined with periapical surgery, emphasizing the importance of proper diagnosis and planning by using cone beam computed tomography (CBCT). This case report presents the proper periapical healing 6 months after the combination of nonsurgical and surgical treatments. It also shows that CBCT is an important auxiliary examination to avoid errors in diagnosis and subsequent treatment of dental anomalies.
Dens invaginatus é uma malformação dentária já bem reconhecida, que provavelmente resulta de uma invaginação do órgão do esmalte para dentro da papila dentária durante o desenvolvimento do dente em questão. O tratamento endodôntico de dentes invaginados pode ser um desafio devido às dificuldades de acesso aos canais radiculares e também devido à complexidade da morfologia interna. Este artigo apresenta o manejo endodôntico e o acompanhamento de um caso raro de segundo pré-molar inferior direito com dens invaginatus Tipo III de Oehlers. O resultado do teste de sensibilidade pulpar ao frio foi positivo para este dente, mas o mesmo estava associado a uma fístula e lesão periapical. Relata-se o tratamento de canal deste dente associado à cirurgia periapical, enfatizando a importância de um correto diagnóstico e plano de tratamento, utilizando a tomografia computadorizada de feixe cônico (TCFC). Este relato de caso mostra reparo periapical adequado 6 meses após a combinação dos tratamentos não-cirúrgico e cirúrgico. Mostra também que a TCFC é um importante exame auxiliar para evitar erros no diagnóstico e posterior tratamento de anomalias dentárias.
This article reports a research on the processes of articulation between the construction of psychological practices and social assistance. The study was carried out through life narratives and professionals of psychology that work or have worked in the field of Social Assistance since the 1990s in the city of Porto Alegre, in the state of Rio Grande do Sul, Brasil. The collection and analysis of these narratives was used as methodological strategy, As a methodological strategy, the collection and analysis of narratives was used, have as referencial theoretician, the social constructionist. Among the obtained results, the mismatch between the training and the professional performance can be highlighted and finally, the idea that the public politics of social assistance is a poorly explored crossing to the other social politics.
Este artigo relata uma pesquisa sobre os processos de articulação entre a construção das práticas do psicólogo e a Assistência Social. O estudo deu-se através das narrativas de vida e profissionais de psicólogos que efetivam ou efetivaram saberes e práticas no campo da Assistência Social, a partir da década de 1990, na cidade de Porto Alegre, Estado do Rio Grande do Sul, Brasil. Como estratégia metodológica utilizou-se a coleta e análise de narrativas tendo, como referencial teórico, o construcionismo. Dentre os resultados, destacam-se o descompasso entre a formação e a prática profissional e a ideia de que a Política Pública de Assistência Social é uma travessia pouco explorada para as demais políticas sociais.
PURPOSE: The purpose of this article is to present three clinical cases of infected immature teeth that were treated by using mineral trioxide aggregate (MTA) as an apical plug. CASES DESCRIPTION: All cases underwent premature interruption of root development as consequence of pulp necrosis. Root canals were instrumented by using chlorhexidine gel 2% (CHX) as auxiliary chemical substance. A paste of calcium hydroxide and CHX was kept for one week as intracanal dressing. In a second appointment, the apical portion of the canals (3-4 mm) was filled with MTA. The remaining portions of the root canals were then obturated by the thermomechanical technique by utilizing gutta-percha condensers and a zinc oxide and eugenol-based root canal sealer. Follow-up periods at both 6 months and 1 year showed radiographic favorable response and absence of symptoms. CONCLUSION: MTA seems to be nowadays, an interesting option of treatment for cases of immature teeth with the advantage of shorter treatment approaches.
OBJETIVO: O objetivo desse artigo é descrever três casos clínicos de dentes com rizogênese incompleta e necrose pulpar tratados com agregado trióxido mineral (MTA) para obtenção de barreira de selamento apical. DESCRIÇÃO DOS CASOS: Todos os casos relatados apresentaram interrupção da formação radicular como consequência da necrose pulpar. Os canais foram instrumentados utilizando gel de clorexidina a 2% como substância química auxiliar e medicados com pasta de hidróxido de cálcio e clorexidina, a qual foi mantida nos canais por uma semana. Em uma segunda consulta, a porção apical dos canais foi selada com barreira apical de MTA, com espessura de aproximadamente 3-4 mm. As demais porções dos canais foram obturadas com técnica de plastificação termomecânica da guta-percha, utilizando cimento à base de óxido de zinco e eugenol. Controle pós-operatório de 6 meses e 1 ano mostraram resposta radiográfica satisfatória e ausência de sintomas. CONCLUSÃO: Atualmente, MTA apresenta-se como uma opção interessante para casos de rizogênese incompleta e necrose pulpar, apresentando como vantagem o menor tempo de tratamento requerido.
PURPOSE: Internal inflammatory root resorption is a rare condition, characterized by progressive loss of tooth substance which starts on the root canal wall. Usually the process is asymptomatic and diagnosed upon routine radiographic examination. The following report shows the treatment of a case of periapical lesion and apical internal resorption that reached the external root surface. CASE DESCRIPTION: A 16 year-old male was referred for a routine dental treatment for oral rehabilitation. Radiographic examination showed a resorptive lesion in the apical third and periapical lesion on tooth 21. Crown down preparation was performed and calcium hydroxide was placed for 2 weeks. An apical plug with white MTA was condensed into the resorption cavity and then the canal was obturated with gutta-percha and AH Plus sealer. The follow-up radiographs showed satisfactory resolution. CONCLUSION: This report showed the results of the treatment with MTA apical plug. The technique avoided an invasive procedure and presented some advantages, like materials biological properties and capable of sealing.
OBJETIVO: A reabsorção radicular interna inflamatória é uma condição rara caracterizada por progressiva perda de substância dentária, que se inicia nas paredes do canal radicular. Geralmente o processo é assintomático e diagnosticado em exame radiográfico de rotina. O presente relato de caso mostra o tratamento de um caso de lesão periapical e reabsorção interna apical que atingiu a superfície radicular externa. DESCRIÇÃO DO CASO: Um paciente do sexo masculino de 16 anos foi encaminhado para tratamento odontológico de rotina para reabilitação oral. O exame radiográfico mostrou uma lesão de reabsorção no terço apical e lesão periapical no dente 21. O preparo coronário foi realizado e hidróxido de cálcio foi colocado por duas semanas. Um tampão com MTA branco foi condensado na cavidade da reabsorção e então o canal foi obturado com guta-percha e cimento AH Plus. As radiografias de acompanhamento mostraram resolução satisfatória. CONCLUSÃO: Este caso mostrou os resultados do tratamento com tampão apical de MTA. A técnica evitou um procedimento invasivo e apresentou algumas vantagens, tais como propriedades biológicas dos materiais e capacidade de selamento.
OBJECTIVE: This study investigated the pulpal effect of topically applied betamethasone to the dentin of rat molars in the vascular phase of inflammation. MATERIAL AND METHODS: Deep cavities were prepared on the occlusal face of the maxillary right and left 1st molars with non-refrigerated inverted-cone steel burs at low speed. Three groups were formed: Group I was composed of right 1st molars; Group II was composed of left 1st molars that received the application of a drop of betamethasone on dentin surface for 5 min; and Group III (control) was composed of right 2nd molars that received no cavity preparation or betamethasone application. Changes in the vascular characteristics of the pulp tissue were checked by calculating the pulp vascular area in relation to its total area and the number of blood vessels per unit area. Data were subjected to ANOVA and Tukey's test (?=0.05). RESULTS: Group I presented a significantly larger number of vessels (p<0.05) than Group II. Regarding the vascular/total area ratio (%), Group I presented statistically significantly higher values (p=0.01) than Groups II and III. CONCLUSION: Betamethasone applied on the dentin of rat teeth proved to reduce the vascular phase of pulp inflammation regarding vessel diameter and number of blood vessels.
OBJECTIVE: This study evaluated whether smear layer removal has any influence on the filling of the root canal system, by examining the obturation of lateral canals, secondary canals and apical deltas. MATERIAL AND METHODS: Eighty maxillary and mandibular canines were randomly divided into two groups, according to their irrigation regimen. Both groups were irrigated with 1% NaOCl during canal shaping, but only the teeth in Group II received a final irrigation with 17% EDTA for smear layer removal. The root canals were obturated with lateral condensation of gutta-percha and the specimens were cleared, allowing for observation under the microscope. RESULTS: In Groups I and II, 42.5% and 37.5% of the teeth, respectively, presented at least one filled canal ramification. Although a larger number of obturated ramifications was found in Group I, there were no statistically significant differences between the two groups (p = 0.4957). CONCLUSIONS: Smear layer removal under the conditions tested in this study did not affect the obturation of root canal ramifications when lateral condensation of gutta-percha was the technique used for root canal filling.