Comparative analysis of bacterial content, levels of lipopolysaccharides and lipoteichoic acid in symptomatic and asymptomatic endodontic infections at different stages of endodontic treatment.

OBJECTIVES: This study aimed to detect the presence of specific bacteria and to evaluate the levels of lipopolysaccharides (LPS) and lipoteichoic acid (LTA) in symptomatic necrotic root canals associated with acute apical abscess (symptomatic group - GI). It also aimed to compare the findings with those presented by asymptomatic necrotic root canals (asymptomatic group - GII) in the different stages of the endodontic treatment. MATERIALS AND METHODS: Microbiological samples were collected from 20 root canals, including purulent collection from acute apical abscesses, before and after chemo-mechanical preparation (CMP) preparation (CMP) with chlorhexidine gel 2% and after 30 days of intracanal medication (ICM) with (Ca[OH]2) + chlorhexidine. The culture method was used to evaluate the efficacy of CMP and ICM. Nested PCR was used to detect the presence of 17 specific bacteria. Levels of LPS were measured by using limulus amebocyte lysate, whereas enzyme-linked immunosorbent assay was used for the quantification of LTA. RESULTS: CMP was effective in reducing the microbial load in both groups (P < 0.05). LPS levels were higher in GI than in GII (P < 0.05). There was a significant reduction in the LPS levels after CMP and ICM (P < 0.05) in GI and GII. LTA levels were significantly reduced in GI after ICM and in GII after CMP and ICM (both P < 0.05). Fusobacterium nucleatum and Enterococcus faecalis were frequently identified in both groups, alone or in combination with each other. CONCLUSION: Different species were detected in all stages of the endodontic treatment. CMP was able to reduce bacterial content and the levels of LPS, but not of LTA in the symptomatic group. High levels of LPS were correlated with spontaneous pain and pain to percussion in the symptomatic group. CLINICAL RELEVANCE: This clinical study showed that chemo-mechanical preparation was able to reduce bacterial load and levels of LPS, but not of LTA in the symptomatic group. Elevated levels of LPS were correlated with the presence of symptomatology.

Efficiency of a digital electrofulguration system in contaminated root canals in vitro.

Decontamination of the root canal (RC) system is essential for successful endodontic therapy. In this in vitro study, it was evaluated the disinfection potential of an electrofulguration device, the Endox® Endodontic System (EES), in RC infected with Enterococcus faecalis. Sixty-five human lower premolars were instrumented with MTwo® system. The specimens were distributed into six experimental groups (n = 10), according to the irrigation protocol: 2% chlorhexidine gel (CHX); CHX + EES; 5.25% sodium hypochlorite (NaOCl); NaOCl + EES; saline solution (SS); and SS + EES. Five specimens were untreated (control). RC samples were collected before (C1) and after EES treatment (C2), after chemo-mechanical preparation (CMP) (C3), and after final EES treatment (C4). All samples were plated for colony forming units (CFU/mL) onto solid media. The data were analyzed by Wilcoxon and Friedman tests for intragroup comparisons and by Kruskal Wallis test followed by Dunn's test for intergroup comparisons (α = 0.05). Treatment with the EES did not significantly reduce the number of CFU/mL as compared to baseline levels (C1 vs. C2, p> 0.05). After CMP (C3), all groups showed a significantly reduced amount of CFU/mL (p <0.05), with no difference between CHX- and NaOCl-treated samples (p >0.05). Lastly, treatment with the EES following CMP (C4) did not significantly reduce the amount of CFU/mL (C3 vs. C4, p> 0.05). To conclude, the use of the Endox® Endodontic System did not result in considerable bacterial reduction at all operative times, while treatment with NaOCl and CHX was equally efficient for this purpose.

Efficiency of a digital electrofulguration system in contaminated root canals in vitro

Abstract Decontamination of the root canal (RC) system is essential for successful endodontic therapy. In this in vitro study, it was evaluated the disinfection potential of an electrofulguration device, the Endox® Endodontic System (EES), in RC infected with Enterococcus faecalis. Sixty-five human lower premolars were instrumented with MTwo® system. The specimens were distributed into six experimental groups (n = 10), according to the irrigation protocol: 2% chlorhexidine gel (CHX); CHX + EES; 5.25% sodium hypochlorite (NaOCl); NaOCl + EES; saline solution (SS); and SS + EES. Five specimens were untreated (control). RC samples were collected before (C1) and after EES treatment (C2), after chemo-mechanical preparation (CMP) (C3), and after final EES treatment (C4). All samples were plated for colony forming units (CFU/mL) onto solid media. The data were analyzed by Wilcoxon and Friedman tests for intragroup comparisons and by Kruskal Wallis test followed by Dunn's test for intergroup comparisons (α = 0.05). Treatment with the EES did not significantly reduce the number of CFU/mL as compared to baseline levels (C1 vs. C2, p> 0.05). After CMP (C3), all groups showed a significantly reduced amount of CFU/mL (p <0.05), with no difference between CHX- and NaOCl-treated samples (p >0.05). Lastly, treatment with the EES following CMP (C4) did not significantly reduce the amount of CFU/mL (C3 vs. C4, p> 0.05). To conclude, the use of the Endox® Endodontic System did not result in considerable bacterial reduction at all operative times, while treatment with NaOCl and CHX was equally efficient for this purpose.

Resumo A descontaminação do sistema do canal radicular (CR) é essencial para o sucesso da terapia endodôntica. Neste estudo in vitro, foi avaliado o potencial de desinfecção de um dispositivo de eletrofulguração, o Endox® Endodontic System (EES), em CR infectado com Enterococcus faecalis. Sessenta e cinco pré-molares inferiores humanos foram instrumentados com o sistema MTwo®. As amostras foram distribuídas em seis grupos experimentais (n = 10), de acordo com o protocolo de irrigação: clorexidina gel a 2% (CHX); CHX + EES; Hipoclorito de sódio 5,25% (NaOCl); NaOCl + EES; solução salina (SS); e SS + EES. Cinco amostras não foram tratadas (controle). As amostras de CR foram coletadas antes (C1) e após o tratamento com EES (C2), após preparo químico-mecânico (PQM) (C3) e após o tratamento final com EES (C4). Todas as amostras foram plaqueadas para unidades formadoras de colônias (CFU / mL) em meio sólido. Os dados foram analisados pelos testes de Wilcoxon e Friedman para comparações intragrupos e pelo teste de Kruskal Wallis, seguidos pelo teste de Dunn para comparações intergrupos (α = 0,05). O tratamento com o EES não reduziu significativamente o número de CFU / mL em comparação com os níveis basais (C1 vs. C2, p> 0,05). Após PQM (C3), todos os grupos apresentaram uma quantidade significativamente reduzida de CFU / mL (p <0,05), sem diferença entre as amostras tratadas com CHX e NaOCl (p> 0,05). Por fim, o tratamento com o EES após PQM (C4) não reduziu significativamente a quantidade de CFU / mL (C3 vs. C4, p> 0,05). Concluindo, o uso do Endox® Endodontic System não resultou em redução bacteriana considerável em todos os momentos operatórios, enquanto os tratamentos com NaOCl e CHX foram igualmente eficientes para esse fim.

Effectiveness of passive ultrasonic irrigation on periapical healing and root canal disinfection: a systematic review.

Objectives To evaluate the effectiveness of passive ultrasonic irrigation (PUI) compared with non-activated irrigation (NAI) on periapical healing and root canal disinfection.Data source A comprehensive search without restrictions was performed in the following systematic electronic databases: PubMed, Scopus, Cochrane, Web of Science, ScienceDirect and OpenGrey. Additional studies were sought through hand-searching in the main endodontic journals.Data selection We included clinical trials that compared PUI and NAI clinical success and root canal disinfection outcomes. The risk of bias was assessed based on the Cochrane Collaboration common scheme for bias assessment. The power analysis of each study was calculated based on the disinfection rates and sample size, and the evidence was qualified using the GRADE tool.Data synthesis A total of 346 non-duplicated studies were retrieved in the systematic search. One study that assessed the clinical success rate through periapical radiographic healing evaluation and two studies that evaluated root canal disinfection through bacterial growth were considered eligible. These three studies were classified as low risk of bias. The study evaluating radiographic treatment outcome showed no statistical difference (P >0.05). The studies demonstrated large variability among methodology and, in general, low power and moderate evidence. Inconclusive results were reported regarding root canal disinfection when comparing PUI to NAI strategies.Conclusions Based on the findings, there was no evidence of effectiveness improvement on periapical healing and bacterial disinfection that supports the use of PUI over the NAI in clinical practice.

Periodontal and endodontic infectious/inflammatory profile in primary periodontal lesions with secondary endodontic involvement after a calcium hydroxide-based intracanal medication.

OBJECTIVE: The aim of the present study was to investigate the effects of a calcium hydroxide-based intracanal medication (ICM) on periodontal and endodontic infectious/inflammatory contents and on periodontal clinical parameters in teeth with primary periodontal lesion and secondary endodontic involvement. MATERIALS AND METHODS: Ten patients with abnormal pulp test results and deep probing depth derived from primary periodontal disease with secondary endodontic involvement were included. Samples were collected from root canals (RC) and periodontal pockets (PP) in order to investigate the microbiological status, levels of endotoxin (LPS), cytokines, and matrix metalloproteinases (MMP), before and after ICM. PCR was used for microbiological assessment. The kinetic-chromogenic LAL assay was used for LPS quantification. Quantikine ELISA kits were used for measurement of IL-1 α, IL-1 ß, TNF-α, PGE2, MMP-2, MMP-3, MMP-8, MMP-9, and MMP-13 levels. The statistical analyses were made using the Friedman and Wilcoxon tests (p < 0.05). T test was used to compare data on periodontal characteristics. RESULTS: ICM did not reduce the number of microorganisms in PP and RC, except for Fusobacterium nucleatum in RC. There was a significant reduction in LPS, MMPs, IL-1 ß, and TNF-α levels in PP after ICM. In RC, LPS, MMP13, PGE2, and IL-1ß levels remained unaltered (p > 0.05); however, the levels of the other MMPs and cytokines were reduced (p < 0.05). After 1 year of the root canal treatment, tooth mobility was significantly reduced (p ≤ 0.05). CONCLUSIONS: The use of a calcium hydroxide-based ICM showed positive effects for periodontal treatment prognosis, as it reduced LPS, cytokine, and MMP levels in periodontal pockets. CLINICAL SIGNIFICANCE: Patients presenting deep probing depth and undergoing periodontal treatment for at least 6 months, with no positive response to periodontal therapy, might benefit with the endodontic treatment.

Evaluation of photodynamic therapy using a diode laser and different photosensitizers against enterococcus faecalis.

Photodynamic therapy (PDT) has been proven to be effective in disinfecting root canals. The aim of this present study was to evaluate the effects of PDT on the viability of Enterococcus faecalis using methylene blue (MB) and malachite green (MG) as photosensitizers. Solutions containing E. faecalis (ATCC 29212) were prepared and harvested by centrifugation to obtain cell suspensions, which were mixed with MB and MG. Samples were individually irradiated by the diode laser at a distance of 1mm for 30, 60, or 120 seconds. Colonyforming units (CFU) were determined for each treatment. PDT for 60 and 120 seconds with MG reduced E. faecalis viability significantly. Similar results were obtained when MB was used as photosensitizer. PDT using MB and MG have antibacterial effect against E. faecalis, showing potential to be used as an adjunctive antimicrobial procedure in endodontic therapy.

Repair of apical root resorption associated with periodontitis using a new intracanal medicament protocol.

Endodontic therapy is indicated for cases of traumatic tooth dislocation associated with pulp necrosis and/or inflammatory resorption. Here we describe the management of a maxillary left lateral permanent incisor that suffered lateral luxation, leading to pulp necrosis and root resorption, in a 13-year-old boy. The traumatized tooth was treated successfully by intracanal medication with calcium hydroxide, 2% chlorhexidine gel and zinc oxide for 12 months without any need to change the dressing, followed by conventional root canal filling. The postoperative course was uneventful and a stable clinical outcome was obtained with evidence of periapical lesion repair and stabilization of the resorption process.

Assessment of coronal leakage of a new temporary light-curing filling material in endodontically treated teeth.

INTRODUCTION: The aim of this study was to evaluate the sealing ability of a new temporary filling material X-Temp LC (DFL, São Paulo, SP, Brazil) compared with that obtained for Coltosol (Vigodent, Rio de Janeiro, RJ, Brazil) and Vitro Fill (DFL, Rio de Janeiro, RJ, Brazil), using a dye penetration test. METHODS: Standard endodontic access cavities were prepared in 75 human premolars. The teeth were divided into five groups (n = 15 for each group), including a positive (no sealing of access cavity) and a negative control (Filtek Z350 XT, 3M, São Paulo, SP, Brazil). In the experimental groups, the access cavities were sealed with one of the three tested materials. After that, the teeth were immersed in 10% Indian ink for 14 days. The teeth were then rinsed, dried, sectioned in bucco-lingual direction and evaluated under a stereomicroscope using scores for dye penetration. Data were analyzed using Kruskall-Wallis and Student-Newman-Keuls tests (α =0.05). RESULTS: Positive control sections exhibited complete dye penetration and negative control had no specimen showing marginal leakage. X-Temp LC and Coltosol showed similar results, with no statistical difference between them. Vitro Fill exhibited the highest dye penetration among the experimental groups. CONCLUSION: The results of this in vitro study suggest that all temporary restorative materials exhibit some degree of marginal leakage. X-Temp LC and Coltosol, however seal better than Vitro Fill glass ionomer cement.

Efficacy of ethylene-diamine-tetra-acetic acid associated with chlorhexidine on intracanal medication removal: a scanning electron microscopy study.

The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid (EDTA) used alone or associated with 2% chlorhexidine gel (CHX) on intracanal medications (ICM) removal. Sixty single-rooted human teeth with fully formed apex were selected. The cervical and middle thirds of each canal were prepared with Gates Glidden drills and rotary files. The apical third was shaped with hand files. The specimens were randomly divided into two groups depending on the ICM used after instrumentation: calcium hydroxide Ca(OH)(2) +CHX or Ca(OH)(2) +sterile saline (SS). After seven days, each group was divided into subgroups according to the protocol used for ICM removal: instrumentation and irrigation either with EDTA, CHX+EDTA, or SS (control groups). All specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy. Two calibrated evaluators attributed scores to each specimen. The differences between the protocols for ICM removal were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between the score of debris obtained in each root canal third. Remains of Ca(OH)(2) were found in all specimens independently of the protocol and ICM used (P > 0.05). Seventeen percent EDTA showed the best results in removing ICM when used alone (P < 0.05), particularly in those associated with CHX. It was concluded that the chelating agent 17% EDTA significantly improved the removal of ICM when used alone. Furthermore, the type of the vehicle associated with Ca(OH)(2) also plays a role in the ICM removal.

Evaluation of photodynamic therapy using a diode laser and different photosensitizers against enterococcus faecalis. / Evaluation of photodynamic therapy using a diode laser and different photosensitizers against enterococcus faecalis.

Photodynamic therapy (PDT) has been proven to be effective in disinfecting root canals. The aim of this present study was to evaluate the effects of PDT on the viability of Enterococcus faecalis using methylene blue (MB) and malachite green (MG) as photosensitizers. Solutions containing E. faecalis (ATCC 29212) were prepared and harvested by centrifugation to obtain cell suspensions, which were mixed with MB and MG. Samples were individually irradiated by the diode laser at a distance of 1mm for 30, 60, or 120 seconds. Colonyforming units (CFU) were determined for each treatment. PDT for 60 and 120 seconds with MG reduced E. faecalis viability significantly. Similar results were obtained when MB was used as photosensitizer. PDT using MB and MG have antibacterial effect against E. faecalis, showing potential to be used as an adjunctive antimicrobial procedure in endodontic therapy.

Influence of irrigation and obturation techniques on artificial lateral root canal filling capacity.

The aim of this study was to evaluate the influence of two different irrigation protocols on artificial lateral root canal filling capacity using different obturation techniques. Sixty single-root human teeth were used. Two artificial lateral canals were created in the apical third. Root canals were instrumented up to a 45 K-file to the working length. Before each file, root canals were irrigated either with 2 mL of 2.5% NaOCl or 2% chlorhexidine gel with further irrigation with saline solution and 3 mL of 17% EDTA. Specimens were randomly divided into three groups according to the obturation technique: (1) lateral compaction technique; (2) Tagger hybrid technique; and (3) thermoplasticized technique using BeeFill 2 in 1. All groups used AH Plus as the root canal sealer. The specimens were decalcified and cleared in methyl salicylate. The total length of lateral canals was observed under X30 magnification with a stereomicroscope and measured on the buccal and lingual root surfaces using Leica IM50 software. The data were submitted to ANOVA and Tukey test (p < 0.05). Among the obturation techniques, BeeFill 2 in 1 showed deeper penetration into all lateral canals than the lateral compaction or Tagger hybrid techniques (p < 0.05). The lateral compaction group showed the worst results (p < 0.05). Irrigants did not affect the outcome; there was no difference between NaOCl and chlorhexidine when the same obturation technique was used (p > 0.05). Regardless of the irrigant used during endodontic procedures, the thermoplasticized techniques showed higher penetration behavior for filling artificial lateral canals than the lateral compaction technique.

Efficacy of different final irrigant activation protocols on smear layer removal by EDTA and citric acid.

The aim of this study was to evaluate the influence of different activation protocols for chelating agents used after chemo-mechanical preparation (CMP), for smear layer (SL) removal. Forty-five single-rooted human premolars with straight canals and fully formed apex were selected. The specimens were randomly divided into three groups depending on the chelating agent used for smear layer removal: distilled water (DW, control group); 17% ethylenediaminetetraacetic acid (EDTA); and 10% citric acid (CA). Each group was further divided into three subgroups according to the activation protocol used: no-activation (NA), manual dynamic activation (MDA), or sonic activation (SA). After CMP, all specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy (SEM). Two calibrated evaluators attributed scores to each specimen. The differences between activation protocols were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between each root canal third. When chelating agents were activated, either by MDA or SA, it was obtained the best cleaning results with no significant difference between EDTA and CA (P > 0.05). Sonic activation showed the best results when root canal thirds were analyzed, in comparison to MDA and NA groups (P < 0.05). The activation of chelating agents, independent of the protocol used, benefits smear layer removal from root canals.

Evaluation of cytotoxicity and physicochemical properties of calcium silicate-based endodontic sealer MTA Fillapex.

INTRODUCTION: The aim of the study was to evaluate the cytotoxicity, radiopacity, pH, and flow of a calcium silicate-based and an epoxy resin-based endodontic sealer, MTA Fillapex (Angelus, Londrina, PR, Brazil) and AH Plus (Dentsply, Konstanz, Germany), respectively. METHODS: Cytotoxicity, radiopacity, and flow evaluation were performed following ISO requirements. The pH level was measured at periods of 3, 24, 72, and 168 hours. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to check the Balb/c 3T3 cells viability at 1- to 4-week periods. Data were statistically analyzed by analysis of variance and the Tukey test with a significance level of 5%. RESULTS: In all tested periods, MTA Fillapex was more cytotoxic than AH Plus (P < .05). Although AH Plus presented higher radiopacity than MTA Fillapex (P < .05), both sealers showed minimum required values. MTA Fillapex presented alkaline pH in all experimental times, whereas AH Plus cement showed a slightly neutral pH and a flow significantly lower than that of MTA Fillapex (P < .05). CONCLUSIONS: Although MTA Fillapex was more cytotoxic than AH Plus, it showed suitable physicochemical properties for an endodontic sealer.

Infuence of irrigation and obturation techniques on artificial lateral root canal filling capacity

The aim of this study was to evaluate the influence of two dif-ferent irrigation protocols on artificial lateral root canalfilling capacity using different obturation techniques. Sixtysingle-root human teeth were used. Two artificial lateralcanals were created in the apical third. Root canals wereinstrumented up to a 45 K-file to the working length. Beforeeach file, root canals were irrigated either with 2 mL of 2.5%NaOCl or 2% chlorhexidine gel with further irrigation withsaline solution and 3 mL of 17% EDTA. Specimens were ran-domly divided into three groups according to the obturationtechnique: (1) lateral compaction technique; (2) Taggerhybrid technique; and (3) thermoplasticized technique usingBeeFill 2 in 1. All groups used AH Plus as the root canal seal-er. The specimens were decalcified and cleared in methylsalicylate. The total length of lateral canals was observedunder X30 magnification with a stereomicroscope and meas-ured on the buccal and lingual root surfaces using Leica IM50software. The data were submitted to ANOVA and Tukey test(p<0.05). Among the obturation techniques, BeeFill 2 in 1showed deeper penetration into all lateral canals than the lat-eral compaction or Tagger hybrid techniques (p<0.05). Thelateral compaction group showed the worst results (p<0.05).Irrigants did not affect the outcome; there was no differencebetween NaOCl and chlorhexidine when the same obturationtechnique was used (p>0.05). Regardless of the irrigant usedduring endodontic procedures, the thermoplasticized tech-niques showed higher penetration behavior for filling artificiallateral canals than the lateral compaction technique.

O objetivo do presente estudo foi avaliar a influência de doisdiferentes protocolos de irrigação na capacidade de penetraçãode canais artificiais, utilizando diferente técnicas de obturação.Sessenta dentes humanos unirradiculares foram utilizados. Doiscanais laterais artificiais foram confeccionados no terço apicaldo dente. Os canais foram instrumentados até uma lima K 45 nocomprimento de trabalho. Antes do uso de cada lima, os canaisradiculares foram irrigados com 2 mL de NaOCl 2.5% ou comClorexidina gel 2% seguido de solução salina. Ambos os gruposreceberam no final da instrumentação 3 mL de EDTA 17%. Osespecimes foram randomicamente separados em 3 subgrupos deacordo com a técnica de obturação utilizada: (1) técnica de com-pactação lateral; (2) técnica híbrida de Tagger; e (3) técnicatermoplástica utilizando o BeeFill 2 em 1. Em todos os grupos ocimento utilizado foi o AH Plus. Depois, os elementos foramdiafanizados utilizando metil salicilato. As extensões de pe -netração dos cimentos nos canais laterais foram realizadas uti-lizando estereomicroscópio (X30). Os dados de cada grupoforam analizados utilizando ANOVA e o teste de Tukey (p<0.05).Dentre as técnicas de obturação, a técnica termoplástica uti-lizando o BeeFill 2 em 1 mostrou a maior penetração em canaislaterais (p<0.05). A técnica de compactação lateral apresentouos piores resultados dentes os grupos testados (p<0.05). Os irri-gantes não afetaram a penetração dos canais laterais; não foramobservados diferenças entre NaOCl e clorexidina, quando amesma técnica de obturação foi utilizada (p>0.05). Pode-se con-cluir que independente da substância química auxiliar utilizada,as técnicas termoplásticas de obturação demonstraram maiorpenetração de canais laterais do que a técnica de compactação lateral.

Influence of irrigation and obturation techniques on artificial lateral root canal filling capacity. / Influence of irrigation and obturation techniques on artificial lateral root canal filling capacity.

The aim of this study was to evaluate the influence of two different irrigation protocols on artificial lateral root canal filling capacity using different obturation techniques. Sixty single-root human teeth were used. Two artificial lateral canals were created in the apical third. Root canals were instrumented up to a 45 K-file to the working length. Before each file, root canals were irrigated either with 2 mL of 2.5

NaOCl or 2

chlorhexidine gel with further irrigation with saline solution and 3 mL of 17

EDTA. Specimens were randomly divided into three groups according to the obturation technique: (1) lateral compaction technique; (2) Tagger hybrid technique; and (3) thermoplasticized technique using BeeFill 2 in 1. All groups used AH Plus as the root canal sealer. The specimens were decalcified and cleared in methyl salicylate. The total length of lateral canals was observed under X30 magnification with a stereomicroscope and measured on the buccal and lingual root surfaces using Leica IM50 software. The data were submitted to ANOVA and Tukey test (p < 0.05). Among the obturation techniques, BeeFill 2 in 1 showed deeper penetration into all lateral canals than the lateral compaction or Tagger hybrid techniques (p < 0.05). The lateral compaction group showed the worst results (p < 0.05). Irrigants did not affect the outcome; there was no difference between NaOCl and chlorhexidine when the same obturation technique was used (p > 0.05). Regardless of the irrigant used during endodontic procedures, the thermoplasticized techniques showed higher penetration behavior for filling artificial lateral canals than the lateral compaction technique.

Infuence of irrigation and obturation techniques on artificial lateral root canal filling capacity

The aim of this study was to evaluate the influence of two dif-ferent irrigation protocols on artificial lateral root canalfilling capacity using different obturation techniques. Sixtysingle-root human teeth were used. Two artificial lateralcanals were created in the apical third. Root canals wereinstrumented up to a 45 K-file to the working length. Beforeeach file, root canals were irrigated either with 2 mL of 2.5%NaOCl or 2% chlorhexidine gel with further irrigation withsaline solution and 3 mL of 17% EDTA. Specimens were ran-domly divided into three groups according to the obturationtechnique: (1) lateral compaction technique; (2) Taggerhybrid technique; and (3) thermoplasticized technique usingBeeFill 2 in 1. All groups used AH Plus as the root canal seal-er. The specimens were decalcified and cleared in methylsalicylate. The total length of lateral canals was observedunder X30 magnification with a stereomicroscope and meas-ured on the buccal and lingual root surfaces using Leica IM50software. The data were submitted to ANOVA and Tukey test(p<0.05). Among the obturation techniques, BeeFill 2 in 1showed deeper penetration into all lateral canals than the lat-eral compaction or Tagger hybrid techniques (p<0.05). Thelateral compaction group showed the worst results (p<0.05).Irrigants did not affect the outcome; there was no differencebetween NaOCl and chlorhexidine when the same obturationtechnique was used (p>0.05). Regardless of the irrigant usedduring endodontic procedures, the thermoplasticized tech-niques showed higher penetration behavior for filling artificiallateral canals than the lateral compaction technique.(AU)

O objetivo do presente estudo foi avaliar a influÛncia de doisdiferentes protocolos de irrigaþÒo na capacidade de penetraþÒode canais artificiais, utilizando diferente técnicas de obturaþÒo.Sessenta dentes humanos unirradiculares foram utilizados. Doiscanais laterais artificiais foram confeccionados no terþo apicaldo dente. Os canais foram instrumentados até uma lima K 45 nocomprimento de trabalho. Antes do uso de cada lima, os canaisradiculares foram irrigados com 2 mL de NaOCl 2.5% ou comClorexidina gel 2% seguido de soluþÒo salina. Ambos os gruposreceberam no final da instrumentaþÒo 3 mL de EDTA 17%. Osespecimes foram randomicamente separados em 3 subgrupos deacordo com a técnica de obturaþÒo utilizada: (1) técnica de com-pactaþÒo lateral; (2) técnica híbrida de Tagger; e (3) técnicatermoplástica utilizando o BeeFill 2 em 1. Em todos os grupos ocimento utilizado foi o AH Plus. Depois, os elementos foramdiafanizados utilizando metil salicilato. As extens§es de pe -netraþÒo dos cimentos nos canais laterais foram realizadas uti-lizando estereomicroscópio (X30). Os dados de cada grupoforam analizados utilizando ANOVA e o teste de Tukey (p<0.05).Dentre as técnicas de obturaþÒo, a técnica termoplástica uti-lizando o BeeFill 2 em 1 mostrou a maior penetraþÒo em canaislaterais (p<0.05). A técnica de compactaþÒo lateral apresentouos piores resultados dentes os grupos testados (p<0.05). Os irri-gantes nÒo afetaram a penetraþÒo dos canais laterais; nÒo foramobservados diferenþas entre NaOCl e clorexidina, quando amesma técnica de obturaþÒo foi utilizada (p>0.05). Pode-se con-cluir que independente da substÔncia química auxiliar utilizada,as técnicas termoplásticas de obturaþÒo demonstraram maiorpenetraþÒo de canais laterais do que a técnica de compactaþÒo lateral.(AU)

A nonsurgical technique for the removal of overextended gutta-percha.

AIM: The present report describes and discusses a nonsurgical technique for the removal of overextended gutta-percha. BACKGROUND: Mechanical irritation results from overextension and the overextended material used during root canal obturation could produce an inflammatory reaction with an area of rarefaction in the periapical tissues. The healing process is not affected by the presence of filling materials as it is well tolerate by the periapical tissues, but it is accepted that a higher failure rate is found in overfilled teeth. CASE REPORT: This clinical report describes one case with an overextended gutta-percha cone and a new nonsurgical technique to remove this material. CONCLUSION: The technique described is a conservative, safe and plausible option to remove extruded gutta-percha in periapical area. CLINICAL SIGNIFICANCE: Overextended gutta-percha cones could increase the failure of endodontic therapy. Commonly surgical procedures are indicated to remove this overextended material, but this nonsurgical technique could be a better treatment alternative and could increase the chances of success.

Assessment of the tip surface of gutta-percha cones after different cutting methods.

The surface of gutta-percha cones was evaluated after using five different cutting methods, including a new TipSnip device. The gutta-percha cones were cut off using: 1) TipSnip, 2) a single cut with a scalpel blade using a gauge, 3) two cuts with a scalpel blade using a gauge, 4) a razor blade against a glass slab or 5) scissors. Samples were examined under stereomicroscopy and observed by three highly qualified evaluators. The Kappa coefficient with a 95% confidence interval was used and all scores were tabulated and analyzed statistically using a nonparametric Kruskal-Wallis test with a 5% significance level. Cutting with scissors produced significant irregularities in the cone surface, providing the worst result. TipSnip, two cuts with scalpel blade, and cut with a razor against a glass slab provided the best results. A regular surface on the tips of gutta-percha cones improves apical fit, and may be achieved by means of different cutting methods.

In vitro antimicrobial activity of phytotherapic Uncaria tomentosa against endodontic pathogens.

The aim of this study was to evaluate the antimicrobial activity of Uncaria tomentosa (Willd.) DC (cat's claw) against Enterococcus faecalis, Staphylococcus aureus, and Candida albicans. Suspensions with 10(8) cells/ml of each microorganism were plated in triplicate on Mueller-Hinton agar. Wells in the agar were made and filled with 2% chlorhexidine (CHX) gel, 2% cat's claw (CC) gel, 2% CHX+CC, and 1% hydroxyethylcellulose (NAT) gel. Inhibition halos were measured after 24 h at 37°C and differences were analyzed using one-way ANOVA. The mean diameter of the microbial growth inhibition zones of 2% CHX+CC against the tested microbial strains ranged from 21.7 to 33.5 mm. This was the most effective substance against E. faecalis and C. albicans, followed by CHX and CC. Against S. aureus, CHX+CC, CHX, and CC showed similar antimicrobial activity (P > 0.05). The results indicate that all the investigated compounds had antimicrobial activity against microorganisms frequently found in infected root-filled teeth.