Izabel Coelho Gomes Camões

Clinical Comparison of the Effectiveness of Single-file Reciprocating Systems and Rotary Systems for Removal of Endotoxins and Cultivable Bacteria from Primarily Infected Root Canals

INTRODUCTION This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria from primarily infected root canals. METHODS Forty-eight primarily infected root canals were selected and randomly divided into 4 groups: WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) (n = 12); Reciproc (VDW, Munich, Germany) (n = 12), ProTaper (Dentsply Maillefer) (n = 12), and Mtwo (VDW) (n = 12). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5% sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts. RESULTS In the baseline samples (ie, samples collected before chemomechanical preparation), endotoxins and cultivable bacteria were recovered from 100% of the root canal samples. No differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems (ie, WaveOne [95.15%] and Reciproc [96.21%]) and with rotary systems (ie, ProTaper [97.98%] and Mtwo [96.34%]) (P < .05). Both single-file reciprocating systems (ie, WaveOne [99.45%] and Reciproc [99.93%]) and rotary systems (ProTaper [99.85%] and Mtwo [99.41%]) were effective in reducing the cultivable bacteria (all P < .05). Moreover, the culture analysis revealed no differences in bacterial load reduction (P > .05). CONCLUSIONS Both single-file reciprocating systems (ie, WaveOne and Reciproc instruments) and rotary systems (ie, ProTaper and Mtwo instruments) showed similar effectiveness in reducing endotoxins and cultivable bacteria from primarily infected root canals, but they were not able to eliminate them from all root canals analyzed.

Diffusion of Ca(OH)2 associated with different vehicles: chromatographic study (high-performance liquid chromatography).

Using high-performance liquid chromatography (HPLC), small amounts of liquid samples in which 25 premolar human teeth were immersed were evaluated. Each tooth was immersed separately in 800-ml flasks with distilled ultra-pure deionized water and remained there for 1678 h after the filling of their canals with Ca(OH)2 associated with different vehicles: group 1: polyethylene glycol and colophon (Calen); group 2: glycerin and camphorated paramonochlorophenol; group 3: camphorated paramonochlorophenol; group 4: glycerin and tricresol formol; and group 5: anesthetic solution (Citanest). Five polyethylene tubes were filled with each of these pastes and placed unsealed in similar flasks. At the end of this period, HPLC analyses of the aqueous medium related to each group were performed to detect other substances that had diffused from the pastes used in the canals of the teeth other than calcium and hydroxyl ions. Although the groups presented different maximum peaks when there was no barrier, they all showed higher values than when the tooth was present. At least 15 substances other than Ca2+ and OH- were detected in the aqueous medium of group 4. Analyzing the HPLC graphs, we concluded that not only Ca2+ and OH-, but also a considerable quantity of other components of the pastes diffused through the dentine and reached the external root surface.

Clinical Influence of Different Intracanal Medications on Th1-type and Th2-type Cytokine Responses in Apical Periodontitis

INTRODUCTION This clinical study assessed the influence of different intracanal medications on Th1-type and Th2-type cytokine responses in apical periodontitis and monitored the levels of bacteria from primarily infection during endodontic procedures. METHODS Thirty primarily infected teeth were randomly divided into 3 groups according to the medication selected: chlorhexidine (CHX), 2% CHX gel; Ca(OH)2/SSL, Ca(OH)2 + SSL; and Ca(OH)2/CHX, Ca(OH)2 + 2% CHX gel (all, n = 10). Bacterial sample was collected from root canals, and the interstitial fluid was sampled from lesions. Culture techniques were used to determine bacterial counts (colony-forming units/mL). Th1 (tumor necrosis factor-α, interferon-γ, and interleukin [IL]-2) and Th2 cytokines (IL-4, IL-5, and IL-13) were measured by enzyme-linked immunosorbent assay. RESULTS All intracanal medication protocols were effective in reducing the bacterial load from root canals (all P < .05) and lowering the levels of Th1-type cytokines in apical lesions (all P < .05), with no differences between them (P > .05). Both Ca(OH)2 treatment protocols significantly increased the levels of Th2-type cytokines (P < .05), with no differences between them (P > .05). Thus, chlorhexidine medication showed the lowest effectiveness in increasing the levels of Th2-type cytokine. After treatment, regardless of the type of medication, the linear regression analysis indicated the down-regulation of Th2-type cytokines by Th1-type cytokines. CONCLUSIONS All intracanal medication protocols were effective in reducing bacterial load and lowering the levels of Th1-type cytokines. Thus, the use of Ca(OH)2 medications contributed to the increase in the Th2-type cytokine response in apical periodontitis.

Estudo Comparativo Entre Duas Técnicas Obturadoras: Condensação Lateral X Híbrida de Tagger

Objective: To compare the quality and the homogeneity of the filling mass of the root canals gotten through two different filling techniques, the Lateral C...

Análise da Adaptação Marginal de Materiais Retrobturadores

Objetivo: Avaliar a capacidade de adaptacao de diferentes materiais retrobturadores as paredes cavitarias do preparo apical. Metodo: Foram realizadas apicetomia e preparo cavitario empregando-se ultra-som em 24 raizes palatinas de molares superiores (extraidos e conservados em timol a 1%). Para a fase de retrobturacao as raizes foram divididas aleatoriamente em 8 grupos contendo 3 amostras cada: G1 - amalgama, G2 - guta percha, G3 - OZE (Oxido de Zinco e Eugenol), G4 - IRM (Intermediate Restorative Material), G5 - N-Rickert, G6 - Ketac-CEM, G7 - Super-EBA, G8 - MTA (Agregado Trioxido Mineral). A seguir os especimes foram fotografados ao microscopio optico (MO) e eletronico de varredura (MEV) com aumentos de 50x e 150x. Os resultados foram analisados por 3 examinadores calibrados e estabelecidos escores (0- adaptacao do material retrobturador em todas as paredes do preparo apical, 1- ausencia da adaptacao do material retrobturador em uma ou duas paredes do preparo apical, 2-ausencia de adaptacao do material retrobturador em tres ou mais paredes do preparo apical). Os dados foram analisados atraves do teste de Kruskal Wallis. Resultados: A media dos escores entre as amostras foi: Amalgama(MO- 1,22 e MEV- 2), guta percha (MO- 1 e MEV- 2), OZE (MO- 1 eMEV- 1,55), IRM (MO- 2 e MEV- 2), N-Rickert (MO- 1,66 e MEV-1,88), Ketac-CEM (MO- 1,66 e MEV- 1,88), Super-Eba (MO- 0,22 eMEV- 0,55) e MTA (MO- 0 e MEV- 0). Verificou-se diferenca estatisticamente significante entre os grupos (p

Analise microbiologica de cones de guta-percha disponiveis no mercado brasileiro

Objective: To analyze the contaminati on on the surface of gutt apercha cones from diff erent manufacturers available in the nati onal market and to identi f...

Microbiological Analysis of Gutta-Percha Cones Available in the Brazilian Market

Objetivo: Analisar a contaminacao na superficie dos cones de guta-percha de diferentes fabricantes disponiveis no mercado nacional e identificar os microrganismos isolados. Metodo: 34 cones de guta-percha acessorios, provenientes de caixas lacradas ou manipuladas, foram analisados. Trinta cones foram divididos, aleatoriamente, em 6 grupos experimentais com 5 cones cada, diferenciados segundo o fabricante e a sua proveniencia (caixas lacradas ou manipuladas). Quatro cones oriundos de caixas lacrada ou manipulada foram utilizados como controles positivo (contaminado com saliva fresca) e negativo (imerso em solucao de hipoclorito de sodio a 5,25% por 1 minuto). As analises microbiologicas foram realizadas submergindo os cones em tubos contendo caldo Brain-Heart Infusion (BHI) e, posteriormente, semeando uma aliquota deste caldo em Agar sangue. A leitura foi realizada atraves da visualizacao de turvacao no caldo ou crescimento de colonias no meio solido. Os dados obtidos foram analisados pelos testes Kruskal-Wallis e Qui Quadrado com nivel de significância de 5%. Resultados: Observou-se crescimento bacteriano em 2 amostras. Os generos encontrados foram Staphylococcus e Bacillus. Os resultados indicaram que 6,67% dos cones de guta-percha de embalagens lacradas ou manipuladas estavam contaminados, mas nao houve diferenca estatistica entre os grupos experimentais. Conclusao: Existe um risco de contaminacao dos cones de guta-percha. Portanto estes materiais devem ser desinfetados a fim de garantir a seguranca necessaria para o sucesso do tratamento endodontico.

Ação do EDTA e do Ácido Cítrico Sobre a Dentina Radicular

1Professora Mestre da Disciplina de Endodonti a do Departamento de Odontoclinica da Universidade Federal Fluminense (UFF), Niteroi/RJ, Brasil. 2Professora Doutora da Disciplina de Endodonti a do Departamento de Odontoclinica da Universidade Federal Fluminense (UFF), Niteroi/RJ, Brasil. 3Especialista em Endodonti a pela Universidade Federal Fluminense (UFF), Niteroi/RJ, Brasil. 4Professora do Curso de Especializacao em Endodonti a da Universidade Federal Fluminense (UFF), Niteroi/RJ, Brasil. 5Aluna do Curso de Especializacao em Endodonti a da Universidade Federal Fluminense (UFF), Niteroi/RJ, Brasil.