Luiz Carlos Feitosa Henriques

Cytokine Analysis in Lesions Refractory to Endodontic Treatment

INTRODUCTION Failure in endodontic treatment is often caused by the persistence of microorganisms in the root canal after therapy. When treatment fails, an immune response develops that is characterized by an extensive network of immunologic mechanisms that lead to the production of cytokines and chemokines. METHODS The objective of this study was to determine the relative messenger RNA (mRNA) expression of IFN-γ, TNF-α, IL-1β, IL-17A, IL-10, and MCP-1 in periapical dental lesions refractory to treatment. Clinical samples were taken from teeth presenting periapical lesions refractory to endodontic treatment (the experimental group) or from healthy teeth with pulp vitality (the control group). Three paper points passing through the root apex (2 mm) were used to collect the samples. The total RNA was extracted from each sample, complementary DNA was synthesized, and quantitative polymerase chain reaction analysis was performed. The Mann-Whitney U test was used to determine the statistical significance of our findings (P < .05). RESULTS Significant differences in the levels of IFN-γ, TNF-α, IL-17A, and MCP-1 mRNA expression were observed in cases refractory to endodontic treatment as compared with the control group. The expression of IL-1β mRNA was not significantly different between the groups. The expression of IL-10 mRNA was insignificant in both the experimental and control groups. CONCLUSIONS A significantly increased expression of TNF-α, IFN-γ, IL-17A, and MCP-1 mRNA was observed in the periapical immune response in cases of endodontic failure. These results suggest that a proinflammatory cytokine profile predominates in these types of dental lesions.

Effects of calcium hydroxide on cytokine expression in endodontic infections.

INTRODUCTION The use of calcium hydroxide is an effective step in killing bacteria that remain after cleaning and shaping procedures. It also induces hard-tissue formation and is effective for stopping inflammatory exudates. METHODS The aim of this study was to assay and to compare the influence of calcium hydroxide on periapical interstitial fluid from human root canals. The mRNA expression levels of the cytokines interferon (IFN)-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-17A, and IL-10 as well as the chemokine MCP-1 were assayed by real-time polymerase chain reaction immediately after root canal cleaning and 15 days later. RESULTS Levels of IL-1β, IFN-γ, IL-10, and the chemokine CCL2/MCP-1 were increased in teeth without endodontic dressings. With calcium hydroxide interappointment dressings, no statistically significant changes were observed in cytokine mRNA expression. However, when comparing teeth that received the medication with those that did not, expression levels of IL-1β, IFN-γ, and IL-10 were statistically lower in those teeth that received calcium hydroxide. CONCLUSIONS Analyses of cytokines and the chemokine CCL-2/MCP-1 demonstrated the benefits of calcium hydroxide as a root canal dressing because it impedes the increase of all mediators during the experimental time.

The Impact of Chlorhexidine-based Endodontic Treatment on Periapical Cytokine Expression in Teeth

INTRODUCTION Root canal treatment typically involves cleaning and shaping procedures followed by treatment with antibacterial endodontic dressing between appointments and, ultimately, 3-dimensional,hermetic filling. Chlorhexidine (CHX) is effective as an irrigation solution and is used as an endodontic dressing. The aim of this study was to examine the influence of CHX on periapical cytokine expression. METHODS Expression levels of the cytokines interferon γ, tumor necrosis factor α, interleukin (IL)-1β, IL-17A, IL-10, and the chemokine monocyte chemoattractant protein-1 (CCL2/MCP-1) were assayed by real-time polymerase chain reaction immediately after root canal cleaning and 15 days later. RESULTS Messenger RNA expression of IL-1β, interferon γ, IL-10, and CCL2/MCP-1 was increased on day 15 in teeth without endodontic dressing. No statistical change was observed in the messenger RNA expression of cytokines when comparing sampling times for teeth that received endodontic dressing. CONCLUSIONS The results show that CHX application between appointments prevented the increase of both proinflammatory and immunoregulatory cytokines 15 days after the dental procedure.

A Eficácia do Hidróxido de Cálcio no Tratamento Endodôntico de Decíduos: Seis Anos de Avaliação

Resumen pt: Objetivo: avaliar os resultados clinicos e radiograficos da utilizacao do hidroxido de calcio no tratamento endodontico em deciduos (com necrose pulpar, ...

Guided Endodontic Access of Calcified Anterior Teeth

&NA; Pulp canal calcification is characterized by the deposition of calcified tissue along the canal walls. As a result, the root canal space can become partially or completely obliterated. Recently, “guided endodontics” has been reported as an alternative solution in cases of partial or completed canal obliteration. Although this technique can enhance minimally invasive access to the calcified canal, it has been shown that the incisal surfaces are often removed during the access of anterior teeth. This report describes 2 cases of guided endodontics using conventional palatal access in calcified anterior teeth and discusses the applicability of this approach in cases of pulp canal calcification with apical periodontitis and acute symptoms. The method demonstrated high reliability and permitted proper root canal disinfection expeditiously, without the unnecessary removal of enamel and dentin in the incisal surface.