Lysozyme antimicrobial activity against Enterococcus Faecalis - a pilot study / Atividade antimicrobiana da lisozima contra Enterococcus Faecalis - um estudo piloto

O preparo químico-mecânico (PQM) do sistema de canais radiculares é essencial para eliminar tecidos infectados e garantir uma desinfecção adequada. O Hidróxido de Cálcio (HC) combinado com o propilenoglicol é frequentemente utilizado como uma pasta intracanal para desinfecção e medicação intraoperatória. No entanto, algumas bactérias, como o Enterococcus faecalis (E. faecalis), podem resistir aos efeitos do hidróxido de cálcio. O Ultracal® é uma medicação de hidróxido de cálcio de alta qualidade e radiopaco usado em procedimentos endodônticos. Já a lisozima é uma substância com propriedades antimicrobianas encontrada em várias partes do corpo humano e tem sido estudada como uma opção promissora para o tratamento de infecções endodônticas. O objetivo do presente estudo foi avaliar e comparar a atividade antimicrobiana do HC com propilenoglicol, Ultracal® e Lisozima contra E. faecalis. Foram realizadas escavações em placas de petri contaminadas com E. faecalis. Após, foi adicionado as medicações intracanais e as placas foram levadas a estufa a 37°C em aerobiose. Os halos de inibição formados foram medidos em 2, 4 e 7 dias. HC apresentou halos de inibição maiores quando comparado as outras medicações e com maior crescimento com o passar dos dias. A lisozima apresentou apenas ação nas primeiras 48 horas, perdendo seu efeito após esse período. Ambas as medicações com hidróxido de cálcio apresentaram valores crescentes. Baseado nos resultados obtidos, conclui-se que as medicações a base de hidróxido de cálcio demonstraram melhor ação contra E. faecalis em ação direta.

The chemical-mechanical preparation (CMP) of root canals system is essential to eliminate infected tissues and ensure adequate disinfection. Calcium hydroxide (CH) combined with propylene glycol is often used as an intracanal medication for intraoperative disinfection and medication. However, some bacteria, such as Enterococcus faecalis (E. faecalis), may resist the effects of calcium hydroxide. Ultracal® is a high-quality radiopaque calcium hydroxide medication used in endodontic procedures. Lysozyme, on the other hand, is a substance with antimicrobial properties found in various parts of the human body and has been studied as a promising option for the treatment of endodontic infections. The aim of this study was to evaluate and compare the antimicrobial activity of CH with propylene glycol, Ultracal®, and Lysozyme against E. faecalis. Petri plates contaminated with E. faecalis were excavated, intracanal medications were added, and the plates were incubated at 37°C in aerobic conditions. The inhibition halos formed were measured at 2, 4, and 7 days. CH showed larger inhibition halos compared to the other medications and exhibited increased growth over the days. Lysozyme showed activity only in the first 48 hours, losing its effect after this period. Both medications with calcium hydroxide showed increasing values. Based on the results obtained, it is concluded that calcium hydroxide-based medications demonstrated better action against E. faecalis in direct action.

Cytocompatibility and Antibiofilm Activity of Calcium Hydroxide Mixed with Cyperus articulatus Essential Oil and Bio-C Temp Bioceramic Intracanal Medicament.

Calcium hydroxide represents the most commonly used intracanal dressing between sessions; however, it may not be effective against all types of microorganisms. Several compounds of plant origin have attracted increasing attention from researchers in recent years. The objective of this study was to evaluate the cytocompatibility and antimicrobial activity of calcium hydroxide associated with the essential oil of Cyperus articulatus and the new bioceramic intracanal medicament Bio-C Temp®. Five experimental groups were designed: group Ca-C. articulatus essential oil; group CHPG-calcium hydroxide associated with propylene glycol; group CHCa-essential oil of C. articulatus associated with calcium hydroxide; and group U-UltraCal® XS; group BCT-Bio-C Temp®. The control group was a culture medium. Cytocompatibility was assessed by the methyltetrazolium (MTT) assay after exposure of the Saos-2 human osteoblast-like cell line to dilutions of commercial products/associations for 24 h and 72 h. The antimicrobial activity against mature Enterococcus faecalis biofilm was evaluated by the crystal violet assay. All commercial products/associations showed a cell viability similar to or even higher than the control group (p > 0.05) for both periods evaluated. C. articulatus essential oil associated or not with calcium hydroxide showed better antibiofilm capacity. C. articulatus associated or not with calcium hydroxide showed superior cytocompatibility and antimicrobial capacity, representing a promissory intracanal medicament.

Apicificação, apicogênese e revascularização, conceitos e conduta clínica: uma revisão de literatura / Apexification, apexogenesis and revascularization, concepts and clinical management: a literature review

O tratamento endodôntico de dentes com rizogênese incompleta requer uma atenção especial, uma vez que o tratamento convencional é inviável e devemos evitar a perda dos dentes permanentes. Na maioria das vezes, as causas que interrompem a formação radicular são os traumatismos dentários e as cáries extensas, que podem atingir a polpa coronária, podendo levar, inclusive, à necrose pulpar. Atualmente, esses casos têm sido tratados por meio da apicificação, apicogênese e da revascularização pulpar, com uso de medicações a base de hidróxido de cálcio, antibiótico e MTA (Agregado trióxido mineral). Nessas técnicas, a intenção é induzir o desenvolvimento radicular completo ou o fechamento apical por tecido duro calcificado. O objetivo deste trabalho foi realizar uma breve revisão de literatura, utilizando artigos científicos disponíveis nas plataformas Café (UFF), Scielo e PubMed, a fim de descrevermos os conceitos de apicificação, apicogênese e revascularização, expondo as suas indicações e condutas clínicas ideais para a realização destes tratamentos. Pode-se concluir que são procedimentos clínicos simples e de conhecimento extremamente importantes para qualquer cirurgião-dentista, uma vez que são tratamentos emergenciais bastante comuns no dia a dia. Além disso, sabe-se da necessidade de manter um dente permanente sadio na boca, que pode evitar grandes problemas no futuro.

Endodontic treatment on teeths with incomplete rhizogenesis requires special attention, since conventional treatment is infeasible and we must avoid the loss of permanent teeth. Most often, the causes that interrupt root formation are dental trauma and extensive caries, which can reach the coronary pulp and may even lead to pulpal necrosis. Currently, these cases have been treated through apexification, apexogenesis and pulpal revascularization, with the use of calcium hydroxide, antibiotic and MTA (Aggregate mineral trioxide) base medications. In these techniques, the intent is to induce complete root development or apical closure by calcified hard tissue. The objective of this work was to carry out a review of literature, using scientific articles available on the Café platform (UFF), Scielo and PubMed, in order to describe the concepts of apexification, apexogenesis and revascularization, exposing their indications and ideal clinical procedures for the realization of these treatments. It can be concluded that they are simple clinical procedures and of knowledge extremely important for any dentist, since they are emergency treatments that are quite common day by day. In addition, it is known that one needs to maintain a permanent healthy tooth in the mouth, which can avoid major problems in the future.

Comparative Analysis of AH Plus Bond Strength to Root Canal Dentin and Adhesive Interface Quality after Calcium Hydroxide Removal using Different Irrigation Protocols.

INTRODUCTION: To evaluate the push-out bond strength (POBS) of AH Plus sealer to root dentin and the adhesive interface quality after calcium hydroxide (Ca(OH)2) intracanal dressing removal with different final irrigation protocols. METHOD: After root canal instrumentation and irrigation, 40 root canals were filled with Ca(OH)2 and sealed. After 14 days, the specimens were randomly distributed according to the irrigation protocols for Ca(OH)2 removal (n = 10): GH2O (control) - distilled water; GNaOCl - 1% NaOCl; GEDTA - 17% EDTA; GEDTA + NaOCl - 17% EDTA + 1% NaOCl. The root canals were filled with AH Plus sealer and gutta-percha. After 7 days, the roots were sectioned into dentin slices and submitted to POBS test and analysis of the adhesive interface under scanning electron microscope. The POBS data were statistically evaluated (analysis of variance and Tukey test). The Kruskal-Wallis and Mann-Whitney tests were used to analyze the adhesive interface (α = 0.05). RESULTS: GH2O, GNaOCl, and GEDTA + NaOCl had similar POBS values, with higher values on the apical third, in comparison with other thirds (P < .05). A homogeneous and free-of-gaps adhesive interface was observed for GH2O, GNaOCl, and GEDTA + NaOCl, with difference between GH2O and GEDTA (P < .05). GH2O and GEDTA + NaOCl presented higher sealer tags formation (P < .05). CONCLUSION: The final rinse with EDTA for Ca(OH)2 dressing removal had a negative effect on the POBS of the filling material to root dentin. The use of EDTA followed by NaOCl had results similar to the distilled water, providing uniform and free-of-gaps adhesive interface, and a higher number of sealer tags.

Effect of Calcium Hydroxide and Antioxidant Agents Filling the Pulp Chamber after Internal Bleaching.

To evaluate the effect of calcium hydroxide (CH), sodium ascorbate (SA) and sodium thiosulfate (ST) filling the pulp chamber on color stability and longevity of teeth after internal bleaching. Crowns of bovine incisors were submitted to internal bleaching and divided into groups according the material used in the pulp chamber: Control, CH, SA, ST. Each group was divided into two subgroups according to the time to perform restorative procedures (7 or 15 days). Color measurement was performed with a spectrophotometer at nine periods. The darkening (ΔE) values were calculated. The Mann-Whitney test was used to statistically analyze the data (p ⟨ 0.05). After bleaching, ΔE values were higher than 3.5, showing that the procedure was effective. After 24 hours, no difference was observed between groups. After 7 days, SA showed higher ΔE than the control group (p ⟨ 0.05). CH and TS did not differ from the control group. In restorations performed after 7/15 days, SA group showed higher values of darkening after 1 and 4 months than the control group (p ⟨ 0.05). SA induced perceptible darkening after bleaching and should not be used to fill the pulp chamber. ST and CH show color stability and longevity after 12 months.

Biological response to endodontic treatment in one versus two-visit: a systematic review and meta-analysis of animal studies.

OBJECTIVES: To perform a systematic review of animal studies that compared the histopathological characteristics between teeth with apical periodontitis after endodontic treatment in one or two visits. MATERIALS AND METHODS: This systematic review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) - CRD42022340849. Studies were collected from PubMed/MEDLINE, LILACS, EMBASE, Livivo, SciELO, Web of Science, Scopus, and Cochrane Library and manual and gray literature searches. Animal studies that evaluated histological characteristics after endodontic treatment of teeth with apical periodontitis in one or two visits were included. Risk of bias analysis of the included studies was performed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool. Data synthesis of the included studies with quantitative data was performed, and meta-analysis was conducted with the Comprehensive Meta-Analysis software, using the random effects model and odds ratio (OR). RESULTS: Eighteen studies met the inclusion criteria (Kappa = 0.891). Meta-analyses indicated values in inflammatory infiltrate intensity with effect size of 5.5% (95% CI: 0.020-0.148; p < 0.001), periodontal ligament thickness: 25.6% (95% CI: 0.134-0.487; p < 0.001), dentin resorption: 13% (95% CI: 0.015-1.141; p = 0.066), cementum resorption: 7.1% (95% CI: 0.015-0.325; p = 0.001), bone resorption: 1.4% (95% CI: 0.002-0.130; p < 0.001), mineralized tissue resorption: 42.8% (95% CI: 0.110-1.671; p = 0.222), biological apical sealing: 13.1% (95% CI: 0.055-0.314; p < 0.001), and presence of microorganisms: 10.3% (95% CI: 0.014-0.747; p = 0.025). CONCLUSIONS: When considering animal studies, the two-visit endodontic treatment, using calcium hydroxide-based intracanal medication, resulted in better biological repair characteristics. CLINICAL RELEVANCE: A two-visit endodontic treatment with calcium hydroxide-based intracanal medication yields superior histopathological outcomes.

Effect of EGCG-based paste as intracanal dressing, in MMPs 2 and 9 expression in dog's periapical lesions

Abstract High expression of MMP-2 and MMP-9 in periapical lesions plays an important role in the degradation of the extracellular matrix. This study aimed to investigate the effect of epigallocatechin-3-gallate (EGCG)-based endodontic paste as an intracanal dressing on the expression of MMP-2 and MMP-9 in periapical lesions. Periapical lesions were experimentally induced in 35 mature beagle dog premolars randomly divided into healthy teeth, untreated periapical lesions, periapical lesions treated in a single session (control groups), and periapical lesions treated in two sessions with EGCG or calcium hydroxide-based pastes (experimental groups). After 120 days, specimens were obtained for histopathologic and immunofluorescence analyses to assess the expression of MMP-2 and MMP-9. The statistical analysis was performed using a p-value of 0.05. Endodontic treatment in two sessions using medication with EGCG and calcium hydroxide-based pastes provided similar repair of the apical and periapical tissues and neoformation of periodontal ligament fibers, cementum, and alveolar bone (p>0.05). The experimental groups treated in two sessions with both medications presented expression of MMP-2 and MMP-9 similar to that in healthy teeth (p>0.05), and significantly lower than teeth treated in a single session or untreated periapical lesions (p <0.001). Expression of MMP-2 and MMP-9 was observed in the cytoplasm of fibroblasts, osteoblasts, cementoblasts, cementocytes, and vascular endothelium. The use of EGCG-based endodontic paste reduced the expression of MMP-2 and MMP-9 and allowed repair of periapical lesions, similar to calcium hydroxide-based paste, and superior to treatment performed in a single session.

Resumo A alta expressão de MMP-2 e MMP-9 em lesões periapicais desempenha um papel importante na degradação da matriz extracelular. Este estudo teve como objetivo investigar o efeito de uma pasta à base de epigalocatequina-3-galato (EGCG) como curativo intracanal na expressão de MMP-2 e MMP-9 em lesões periapicais. Lesões periapicais foram induzidas experimentalmente em 35 pré-molares de cães da raça beagle, maduros, divididos aleatoriamente em dentes saudáveis, lesões periapicais não tratadas, lesões periapicais tratadas em uma única sessão e lesões periapicais tratadas em duas sessões com a pasta de EGCG ou pasta à base de hidróxido de cálcio. O operador monitorou os animais e realizou a eutanásia após 120 dias para análises histopatológicas e de imunofluorescência para avaliar a expressão de MMP-2 e MMP-9. A análise estatística foi realizada utilizando p=0,05. O tratamento endodôntico em duas sessões com pasta à base de EGCG e pasta à base de hidróxido de cálcio proporcionou níveis semelhantes de reparação dos tecidos apicais e periapicais e neoformação de fibras do ligamento periodontal, cemento e osso alveolar. Em ambos os grupos, a expressão de MMP-2 e MMP-9 foi mínima, sendo observada no citoplasma de fibroblastos, osteoblastos, cementoblastos, cementócitos e endotélio vascular. Em ambos os grupos tratados em duas sessões, a expressão de MMP-2 e MMP-9 foi semelhante à dos dentes hígidos e significativamente menor do que nas lesões periapicais tratadas em sessão única ou não tratadas (p < 0,001). O uso da pasta à base de EGCG reduziu a expressão de MMP-2 e MMP-9 e permitiu o reparo de lesões periapicais, semelhante à pasta à base de hidróxido de cálcio, e foi superior ao tratamento realizado em sessão única.

CTZ and Calcium Hydroxide Pastes Did Not Cause Hepatic and Renal Alterations in Mice

ABSTRACT Objective: To evaluate the possible renal and hepatic alteration by root canal filling pastes in mice. Material and Methods: Fifty-four mice were divided into nine groups and received one polyethylene tube implant containing two filling pastes (CTZ or calcium hydroxide pastes). Empty polyethylene tubes were used as a negative control. All tubes were implanted subcutaneously in the back of the mice. After time intervals of 7, 21, and 63 days, 1.5 mL of blood was collected by cardiac puncture, and serum samples were used for serological testing. Urea, creatinine, aspartate transferase (AST), alanine transferase (ALT), alkaline phosphatase (ALP), and gamma-glutamyltransferase (GGT) were evaluated. Data were analyzed by 2-way ANOVA (p<0.05). Results: When comparing CTZ and calcium hydroxide pastes and empty tubes and experimental time intervals, no significant differences in the results were found for any of the biochemical parameters analyzed (p>0.05). No differences were observed in the interactions (material*experimental time intervals) and the biochemical parameters analyzed (p>0.05). Conclusion: CTZ and calcium hydroxide pastes did not cause hepatic and renal alterations in mice, demonstrating the pastes' safety.

Evaluation of different methods of calcium hydroxide removal from root canals with simulated internal resorptions / Avaliação de diferentes métodos de remoção de hidróxido de cálcio de canais radiculares com reabsorções internas simuladas

Objective: This study evaluated different methods of calcium hydroxide (CH) removal from root canals with simulated internal resorptions using microcomputed tomography (micro-CT). Material and Methods: Sixty acrylic resin blocks with simulated root canals and internal resorptions were prepared using a Reciproc R25 file and then filled with CH. The blocks were divided into five test groups (n=12) according to the method used for CH removal: hand files (HF), Easy Clean (EC), passive ultrasonic irrigation (PUI), XP-Endo Finisher (XP), XP-Endo Finisher + PUI (XP+PUI). The blocks were scanned using a SkyScan 1172 scanner before and after CH removal to measure the volume and percentage of CH removal. The OriginPro 2017 software was used for statistical analyses. The level of significance was set at p<0.05 for all tests. Results: No method under study removed all CH. All methods had similar results in the cervical third (P>0.05). The percentage of CH removal was significantly greater in the area of internal resorption and along the total length of the canal in the XP+PUI group (P<0.05). The best results of CH removal were found in the apical third of roots in the XP+PUI and PUI groups (P>0.05). Conclusion: No method removed all CH from the root canals, but the combined XP+PUI method removed more CH than the other methods, especially from the area of the internal resorption(AU)

Objetivo: Este estudo avaliou diferentes métodos de remoção de hidróxido de cálcio (CH) de canais radiculares com reabsorções internas simuladas por meio de microtomografia computadorizada (micro-CT). Material e Métodos: Sessenta blocos de resina acrílica com canais radiculares simulados e reabsorções internas foram preparados com lima Reciproc R25 e posteriormente preenchidos com CH. Os blocos foram divididos em cinco grupos de teste (n=12) de acordo com o método utilizado para remoção de CH: limas manuais (HF), Easy Clean (EC), irrigação ultrassônica passiva (PUI), XP-Endo Finisher (XP), XP -Endo Finalizador + PUI (XP + PUI). Os blocos foram escaneados usando um scanner SkyScan 1172 antes e depois da remoção do CH para medir o volume e a porcentagem de remoção do CH. O software OriginPro 2017 foi utilizado para análises estatísticas. O nível de significância foi estabelecido em p<0,05 para todos os testes. Resultados: Nenhum método em estudo removeu todos o CH. Todos os métodos tiveram resultados semelhantes no terço cervical (P>0,05). A porcentagem de remoção de CH foi significativamente maior na área de reabsorção interna e ao longo do comprimento total do canal no grupo XP+PUI (P<0,05). Os melhores resultados de remoção de CH foram encontrados no terço apical das raízes nos grupos XP+PUI e PUI (P>0,05). Conclusão: Nenhum método removeu todo o CH dos canais radiculares, mas o método combinado XP+PUI removeu significativamente mais CH do que os outros métodos, especialmente da área de reabsorção interna (AU)

Does the liner material influence pulpal vitality in deep carious cavities submitted to selective caries removal? A network meta-analysis review.

OBJECTIVES: To evaluate whether the restorative material in direct contact with the dentin influences pulp vitality in primary and permanent teeth with deep carious lesions restored after selective caries removal (SCR). MATERIAL AND METHODS: Systematic searches of databases MEDLINE via PubMed, Scopus and ISI Web of Science were performed for primary and permanent teeth. Inclusion criteria were applied for title and abstract reading of databases search results. After full texts review of included studies, those that did not meet exclusion criteria were excluded from meta-analysis. RESULTS: For meta-analysis, 2 studies were included for permanent teeth and 6 for primary teeth. The failure events reported were meta-analyzed using two statistical methods: standard pairwise meta-analysis (SPMA) and network meta-analysis (NMA). The SPMA identified similar failure occurrence of restorations performed with calcium hydroxide (CH) and other liner materials (RR 0.84, 95% CI 0.41, 1.74; p = 0.64), no significant difference between the use of alternative liners or CH regardless deciduous or permanent teeth (RR 0.79, 95% CI 0.36, 1.71; p = 0.55) and similar risk of failing at different follow-ups for all liner materials tested (RR 0.77, 95% CI 0.35, 1.70; p = 0.52). Probabilistic analysis indicated GIC as liner material with the highest probability of clinical success (SUCRA = 72.76%), and CH ranked as the worst liner material (SUCRA = 21.81%). CONCLUSION: Pulpal vitality was not affected by material used as liner after selective caries removal in deep carious cavities. CLINICAL RELEVANCE: Current clinical evidence supports the weak recommendation to not use calcium hydroxide as liner after SCR.

Biocompatibility, Biomineralization and Induction of Collagen Maturation with the Use of Calcium Hydroxide and Iodoform Intracanal Dressing.

Biocompatibility and biomineralization of root canal dressings are important requirements for periapical healing. This study evaluated the inflammatory response, biomineralization and tissue repair by collagen fiber maturation in the subcutaneous tissue of rats. Eighteen Wistar rats (n = 6) received subcutaneous implants: calcium hydroxide + propylene glycol [CH+P], calcium hydroxide + propylene glycol + iodoform [CH+P+I], iodoform + carbowax [I+Cwax] and carbowax [Cwax]. Extra empty tubes were used as a control [C]. After 7, 15 and 30 days, the implants were removed with surrounding tissue for staining of hematoxylin-eosin, Von Kossa, picrosirius red and without staining for analysis under polarized light. Results were analyzed via Kruskal-Wallis followed by Dunn testing for nonparametric data and ANOVA followed by a Tukey post hoc test for parametric data (p < 5%). At 7 days, all groups showed a moderate inflammatory reaction and thick fibrous capsule, except the [Cwax] group, with a severe inflammatory infiltrate (p < 0.05). After 15 days, all groups but control had a decrease in inflammatory response. At 30 days, all groups presented a mild reaction and thin fibrous capsule (p > 0.05). Only groups containing calcium hydroxide were found to be positive using Von Kossa staining and polarized light in all periods. At 7 days, all groups showed a higher proportion of immature fibers. At 15 days, the [CH+P] and [Cwax] groups increased their proportion of mature/immature fibers. At 30 days, only the [CH+P] group presented a significant prevalence of mature collagen fibers (p < 0.05). All groups showed biocompatibility, but only groups containing calcium hydroxide induced biomineralization. The addition of iodoform delayed tissue healing.

Analysis of pH, calcium ion release, and energy dispersive spectroscopy of a bioceramic root canal dressing

Abstract This study compared the pH and calcium ion release of calcium silicate- (Bio-C Temp) and calcium hydroxide-based (Ultracal XS) medications. Intracanal remnants of both medications were also evaluated using SEM-EDS after the removal protocol. Thirty-five bovine teeth were prepared. Fifteen were filled with Bio-C Temp and 15 with Ultracal XS. Five remained without intracanal medication (control group). Five samples from each experimental time (i.e.. 24, 72, and 168 hours) were used to measure pH and calcium ions release using a digital pH meter and microplate reader, respectively. Afterward, the peaks of the chemical elements composing both medications were analyzed in SEM-EDS. One-way ANOVA and Tukey's post hoc test analyzed the pH and calcium ion release data. Student's t-test compared the medications in each experimental time. SEM-EDS described the percentage of chemical elements in the samples. Bio-C Temp and Ultracal XS showed a significant pH increase from 24 to 168 hours (p<0.05). Ultracal XS showed a higher pH value at 24 hours than Bio-C Temp (p<0.05) but were similar at 72 and 168h (p > 0.05). Calcium ion release did not depend on the experimental period (p > 0.05). Bio-C Temp showed lower calcium ions release than Ultracal XS at 24 hours (p<0.05). SEM-EDS analyses showed the remains of both medications, but the concentration of Si, Al, and W ions was present only in the calcium silicate-based medication. Bio-C Temp presented alkaline pH and a satisfactory calcium ion release over the time. The remaining of both medications were present after the protocols for paste removal.

Resumo Este estudo comparou o pH e a liberação de íons cálcio de medicações intracanais a à base de silicato de cálcio (Bio-C Temp) e à base de hidróxido de cálcio (Ultracal XS). Remanescentes de ambas as medicações também foram avaliados usando microscopia eletrônica de varredura e espectroscopia de dispersão de energia após o protocolo de remoção. Trinta e cinco dentes bovinos foram preparados. Quinze dentes foram preenchidos com Bio-C Temp e 15 com Ultracal XS. Cinco permaneceram sem medicação intracanal (grupo controle). Cinco amostras de cada tempo experimental (ou seja, 24, 72 e 168 horas) foram usadas para medir o pH e a liberação de íons de cálcio usando um medidor de pH digital e um leitor de microplacas, respectivamente. Em seguida, os picos dos elementos químicos que compõem os dois medicamentos foram analisados ​​em microscopia eletrônica de varredura e por espectroscopia de dispersão de energia. Os testes One-way ANOVA e post hoc de Tukey analisaram os dados de pH e liberação de íons cálcio. O teste t de Student comparou as medicações em cada tempo experimental. A microscopia eletrônica de varredura e a espectroscopia de dispersão de energia descreveu a porcentagem de elementos químicos nas amostras. O Bio-C Temp e o Ultracal XS mostraram um aumento significativo de pH de 24 a 168 horas (p<0,05). O Ultracal XS apresentou um valor de pH mais alto em 24 horas do que o Bio-C Temp (p<0,05), mas foi semelhante em 72 e 168h (p > 0,05). A liberação de íons cálcio não dependeu do período experimental (p> 0,05). O Bio-C Temp apresentou menor liberação de íons de cálcio do que Ultracal XS em 24 horas (p<0,05). As análises de microscopia eletrônica de varredura e espectroscopia de dispersão de energia mostraram remanescentes de ambas as medicações, mas a concentração de íons Si, Al e W estavam presentes apenas na medicação à base de silicato de cálcio. O Bio-C Temp apresentou pH alcalino e maior liberação de íons cálcio. Remanescentes de ambas as medicações estiveram presentes após os protocolos de remoção da pasta.

Successful nonsurgical treatment of type II dens invaginatus with 5 root canals using a self-adjusting file: a case report.

The present report describes the endodontic treatment of an Oehlers type II dens invaginatus in a maxillary lateral incisor with 5 root canals, an extremely rare condition. Apical periodontitis and related symptoms were noted. Cone-beam computed tomography was used to aid the diagnosis, reveal tooth morphology, and assist in canal location. The pulp chamber was carefully accessed, and the root canals were explored under magnification. All root canals were prepared with an R25 Reciproc Blue system and sodium hypochlorite (NaOCl) irrigation. After initial preparation, a self-adjusting file (SAF) with NaOCl and ethylenediaminetetraacetic acid was used to complement the disinfection. Additionally, calcium hydroxide medication was applied. Vertical compaction was used to fill the canals with a calcium silicate-based endodontic sealer and gutta-percha. After 12 months, the patient exhibited healing of the periapical region, absence of symptoms, and normal dental function. In conclusion, this nonsurgical treatment protocol was successful in promoting the cure of apical periodontitis. Both complementary disinfection with an SAF and use of calcium hydroxide medication should be considered when choosing the best treatment approach for dens invaginatus with very complex anatomy.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) - Bio-C Temp and Ultracal - after different activation protocols in teeth with simulated internal root resorption. Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05). There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05). Due to this, it can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

Aims: This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) -Bio-C Temp and Ultracal -after different activation protocols in teeth with simulated internal root resorption.Materials and methods: Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05).Results:There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05).Conclusion:It can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

Aims: This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) -Bio-C Temp and Ultracal -after different activation protocols in teeth with simulated internal root resorption.Materials and methods: Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05).Results:There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05).Conclusion:It can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption

Mechanism of action of Bioactive Endodontic Materials

Abstract A continuous search for bioactive materials capable of supporting the replacement of damaged pulp tissue, with effective sealing potential and biocompatibility, has represented the attention of studies over the last decades. This study involves a narrative review of the literature developed by searching representative research in PUBMED/MEDLINE and searches in textbooks associated with the mechanism of action of bioactive materials (calcium hydroxide, mineral trioxide aggregate (MTA), and calcium silicate cements). The reflective analysis of the particularities of the chemical elements of these materials, considering the tissue and antibacterial mechanism of action, allows a better understanding of the characteristics and similarities in their tissue responses. Calcium hydroxide paste remains the antibacterial substance of choice as intracanal dressing for the treatment of root canal system infections. Calcium silicate cements, including MTA, show a favorable biological response with the stimulation of mineralized tissue deposition in sealed areas when in contact with connective tissue. This is due to the similarity between the chemical elements, especially ionic dissociation, the potential stimulation of enzymes in tissues, and the contribution towards an alkaline environment due to the pH of these materials. The behavior of bioactive materials, especially MTA and the new calcium silicate cements in the biological sealing activity, has been shown to be effective. Contemporary endodontics has access to bioactive materials with similar properties, which can stimulate a biological seal in lateral and furcation root perforations, root-end fillings and root fillings, pulp capping, pulpotomy, apexification, and regenerative endodontic procedures, in addition to other clinical conditions.

Resumo Uma busca contínua de materiais bioativos com capacidade de substituir o tecido pulpar danificado, com efetiva capacidade de selamento e biocompatibilidade, tem representado a atenção e foco de muitos estudos ao longo das últimas décadas. Este estudo envolve uma revisão narrativa da literatura desenvolvida por meio de pesquisas representativas encontradas no PUBMED/MEDLINE e pesquisas em livros didáticos associadas ao mecanismo de ação de materiais bioativos (hidróxido de cálcio, agregado de trióxido mineral (MTA) e cimentos de silicato de cálcio). A presente análise reflexiva das particularidades dos elementos químicos destes materiais bioativos, considerando o mecanismo de ação tecidual e antibacteriano, possibilita um melhor entendimento das características e similaridades no comportamento tecidual. A pasta de hidróxido de cálcio continua sendo a substância antibacteriana de escolha como medicação intracanal para o tratamento das infecções do sistema de canais radiculares. Este fato se deve a disponibilidade química de íons cálcio e hidroxila do hidróxido de cálcio aos tecidos, e a inibição enzimática bacteriana. Os cimentos de silicato de cálcio, dentre os quais inclui o MTA, apresentam uma resposta biológica favorável ao estímulo à deposição de tecido mineralizado nas áreas seladas e em contato com tecido conjuntivo. Este fato é decorrente da similaridade entre os elementos químicos, em especial devido a dissociação iônica, ao potencial estímulo de enzimas teciduais, e a contribuição com um meio alcalino decorrente do pH destes materiais. O comportamento dos materiais bioativos, em especial o MTA e os novos cimentos de silicato de cálcio na atividade de selamento biológico mostraram efetivos. A endodontia contemporânea atualmente conta com o potencial de materiais bioativos com propriedades análogas capaz de estimular o selamento biológico em perfurações radiculares laterais e de furca, em obturações radiculares, capeamento pulpar, pulpotomia, apicificação e procedimentos endodônticos regenerativos, além de outras condições clínicas.

Effects of Calcium Hydroxide Paste in Different Vehicles on Bacterial Reduction during Treatment of Teeth with Apical Periodontitis.

INTRODUCTION: This clinical study evaluated the antibacterial effects of calcium hydroxide associated with different vehicles during the treatment of infected teeth with apical periodontitis. METHODS: Bacteriologic samples were taken from 90 necrotic root canals of teeth with apical periodontitis before (S1) and after preparation with a rotary nickel-titanium instrument system and 2.5% sodium hypochlorite irrigation (S2). The teeth were distributed in 3 groups according to the intracanal medication used, which consisted of a calcium hydroxide paste in glycerin, camphorated paramonochlorophenol/glycerin (CHPG), or 2% chlorhexidine for 1 week, and then another sample was taken (S3). The frequency of bacteria-positive cases and the reduction of bacterial counts were evaluated by quantitative real-time polymerase chain reaction. RESULTS: Substantial intracanal bacterial reduction was observed after preparation in the 3 groups (P < .001). After calcium hydroxide paste in glycerin medication, the number of bacteria-positive cases decreased from 20/29 (69%) to 17/29 (59%); however, the mean bacterial counts increased 8.4% from S2 to S3. Medication with CHPG reduced the number of bacteria-positive cases from 17/29 (59%) to 15/29 (52%), with a significant mean S2-S3 reduction of 71% (P < .05). In the chlorhexidine group, the number of bacteria-positive cases decreased from 21/30 (70%) to 17/30 (57%) after medication, with a mean S2-S3 reduction of 55%, which, however, was not statistically significant (P > .05). Intergroup comparisons showed no significant differences (P > .05). CONCLUSION: Comparison between the 3 calcium hydroxide pastes showed no significant differences in antibacterial effectiveness in the main root canal. However, only the CHPG paste showed a significant reduction in bacterial counts when postpreparation and postmedication samples were compared.

Effect of different activation methods on the intratubular penetration of CaOH2 paste: Ex-vivo analysis by confocal laser scanning microscopy.

The aim of this study was to evaluate the maximum penetration depth (MPD) and penetration area (PA) of CaOH2 paste agitated by different methods and to measure the pH after performing these methods. Fifty-five mandibular premolars were divided into control, GL and 4 experimental groups, GEC, GXP, GEDDY and GI (n = 11), where the paste was agitated with Easy Clean, XP-endo Finisher, EDDY and Irrisonic, respectively. The canals were instrumented and irrigated with NaOCl. The paste was manipulated with propylene glycol and rhodamine B dye. Root sections were examined using confocal laser scanning microscopy. There was no difference between groups regarding PA (p > 0.05). At 5 mm, MPD was greater in GEC than in GL or GEDDY, and greater in GI than in GL (p < 0.05). At 2 mm, MPD was greater in GEC than in the other groups (p < 0.05). In conclusion, both Easy Clean and Irrisonic promoted deeper paste penetration and were associated with higher pH levels.

Investigation of the effect of indirect pulp capping materials on dentin mineral density

Aim: To evaluate the potential of inducing mineral density changes of indirect pulp capping materials applied to demineralized dentin. Methods: A total of 50 cavities were prepared, 5 in each tooth, in extracted ten molars without caries, impacted or semi-embedded. The cavities were scanned by microcomputed tomography (µ-CT) after creating artificial caries by microcosm method (pre-treatment). Each cavity was subjected to one of 5 different experimental conditions: control (dental wax), conventional glass ionomer cement (Fuji IX GP Extra), resin-modified calcium silicate (TheraCal LC), resin-modified calcium hydroxide (Ultra-Blend Plus), MTA (MM-MTA) and the samples were kept under intrapulpal pressure using simulated body fluid for 45 days. Then, the second µ-CT scan was performed (post-treatment), and the change in dentin mineral density was calculated. Afterward, elemental mapping was performed on the dentinal surfaces adjacent to the pulp capping agents of 5 randomly selected samples using energy dispersive X-ray spectroscopy (EDS) apparatus attached to a scanning electron microscope (SEM). The Ca/P ratio by weight was calculated. Friedman test and Wilcoxon Signed Ranks test were used to analyze the data. Results: There was a significant increase in mineral density values of demineralized dentin after treatment for all material groups (p<0.05). Resin-modified calcium silicate had similar efficacy to MTA and conventional glass ionomer cement, but was superior to resin-modified calcium hydroxide in increasing the mineral density values of demineralized dentin. Conclusions: Demineralized dentin tissue that is still repairable can be effectively preserved using materials with remineralization capability