Comparação da propriedade antimicrobiana da clorexidina e do hipoclorito de sódio como irrigantes endodônticos: revisão integrativa / Comparison between the antimicrobial properties of chlorhexidine and sodium hypochlorite as endodontic irrigants: an integrative review / Comparación de la propiedad antimicrobiana de la clorhexidina y el hipoclorito de sodio como irrigantes endodónticos: revisión integradora

Introdução:Durante o tratamento endodôntico, devido às complexidades anatômicas dos canais radiculares, a ação mecânica dos instrumentos não é suficiente para a completa desinfecção dos condutos. Dessa forma, se faz necessário o uso de soluções irrigadoras que possampotencializar a desinfecção do sistema de canais radiculares. Objetivo:Realizar uma revisão integrativa da literatura para comparar as propriedades antimicrobianas da clorexidina com o hipoclorito de sódio.Metodologia:A busca na literatura foi realizada no período de setembro de 2019 a agosto de 2021, nas seguintes bases de dados: PUBMED/MEDLINE, LILACS e SCIELO. Utilizando os descritores: clorexidina, hipoclorito de sódio, irrigante do canal radicular e limpeza. Utilizou-se como critérios de busca, trabalhos experimentais laboratoriais in vitro, publicados entre os anos de 2017 e 2021.Resultados:Foram encontrados 165 artigos, dos quais 15 foram selecionados ao final do processo. 8 trabalhos não encontraram diferença estatisticamente significativa entre a clorexidina e o hipoclorito,5 artigos apresentaram resultados superiores dohipoclorito de sódioem 2 a clorexidina foi superior. Conclusões:Após análise da literatura, observamos semelhança entre a ação antimicrobiana do hipoclorito de sódioe da clorexidina, e podemos concluir que ambas apresentam boa ação antimicrobiana, justificando seu uso clinicamente (AU).

Introduction:During endodontic treatment, due to the anatomical complexities of the root canals, the mechanical action of the instruments is not sufficient for the complete disinfection of the canals. Thus, it is necessary to use irrigating solutions that can makethe disinfection of the root canal system.Objective:Conduct an integrative literature review to compare the antimicrobial properties of chlorhexidine with sodium hypochlorite.Methodology:The literature search was carried out from September 2019 to August 2021, in the following databases: PUBMED/MEDLINE, LILACS and SCIELO. Using the descriptors: chlorhexidine, sodium hypochlorite, root canal irrigant and cleaning. As search criteria, in vitro laboratory experimental works published between 2017 and 2021 were used.Results:A total of 165 articles were found, of which 15 were selected at the end of the process. 8 studies did not find a statistically significant difference between chlorhexidine and hypochlorite, 5 articles showed superior results for NaOCl and in 2 chlorhexidine was superior.Conclusions:After analyzing the literature, we observed a similarity between the antimicrobial action of sodium hypochlorite and chlorhexidine, and we can conclude that both have good antimicrobial action, justifying their clinical use (AU).

Introducción:Durante el tratamiento endodóntico, debido a las complexidades anatómicas de los conductos radiculares, la acción mecánica de los instrumentos no es suficiente para la desinfección completa de los conductos. Por lo tanto, es necesario utilizar soluciones de irrigación que puedan mejorar la desinfección del sistema de conductos radiculares.Objetivo: Realice una revisión integradora de la literatura para comparar las propiedades antimicrobianas de la clorhexidina con el hipoclorito de sodio.Metodología: La búsqueda bibliográfica se realizó desde septiembre de 2019 hasta agosto de 2021, en las siguientes bases de datos: PUBMED/MEDLINE, LILACS y SCIELO. Usando los descriptores: chlorhexidine, sodium hypochlorite, root canal irrigant and cleaning. Como criterio de búsqueda se utilizaron trabajos experimentales de laboratorio in vitro publicados entre 2017 y 2021.Resultados: Se encontraron un total de 165 artículos, de los cuales 15 fueron seleccionados al final del proceso. 8 estudios no encontraron diferencia estadísticamente significativa entre clorhexidinae hipoclorito, 5 artículos mostraron resultados superiores para NaOCl y en 2 la clorhexidina fue superior.Conclusiones: Después de analizar la literatura, observamos una similitud entre la acción antimicrobiana del hipoclorito de sodio y la clorhexidina,y podemos concluir que ambos tienen una buena acción antimicrobiana, lo que justifica su uso clínico (AU).

Effect of Passive Ultrasonic Irrigation on Enterococcus faecalis from Root Canals: An Ex Vivo Study.

Endodontic irrigation aims to clean and disinfect the root canal system. Passive ultrasonic irrigation (PUI) is based on the use of an ultrasound-activated instrument into the root canal filled with irrigant. The aim of this study was to evaluate, ex vivo, the effectiveness of PUI in eliminating Enterococcus faecalis from root canals. Seventy-five extracted human single-root teeth were used. After root canal preparation, specimens were inoculated with E. faecalis and incubated at 37 °C for 21 days. Specimens were distributed into five groups (n=15), according to the irrigation method: PUI + saline solution (PUI/SS); PUI + 1% NaOCl (PUI/NaOCl); conventional needle irrigation (CNI) + saline solution (CNI/SS); CNI + 1% NaOCl (CNI/NaOCl); No irrigation (control). Microbiological samples were collected at three time points: initial (21 days after inoculation), post-irrigation (immediately after irrigation), and final (7 days after irrigation). Data were obtained in CFU mL-1 and subjected to analysis by ANOVA and Tukey's tests at 5% significance level. The post-irrigation samples did not demonstrate statistical difference between PUI/SS and CNI/SS nor between PUI/NaOCl and CNI/NaOCl (p>0.05), but PUI/NaOCl and CNI/NaOCl had lower CFU mL-1 number than the other groups (p>0.05). Statistically significant difference was observed between the initial and post-irrigation samples and between the post-irrigation and final samples (p<0.05) in all groups, except in the control. The final samples of all groups presented bacterial counts similar to the initial samples. PUI or CNI with 1% NaOCl contribute to disinfection, but are unable to eradicate E. faecalis from the root canal system.

Effect of Passive Ultrasonic Irrigation on Enterococcus faecalis from Root Canals: An Ex Vivo Study

Endodontic irrigation aims to clean and disinfect the root canal system. Passive ultrasonic irrigation (PUI) is based on the use of an ultrasound-activated instrument into the root canal filled with irrigant. The aim of this study was to evaluate, ex vivo, the effectiveness of PUI in eliminating Enterococcus faecalis from root canals. Seventy-five extracted human single-root teeth were used. After root canal preparation, specimens were inoculated with E. faecalis and incubated at 37 °C for 21 days. Specimens were distributed into five groups (n=15), according to the irrigation method: PUI + saline solution (PUI/SS); PUI + 1% NaOCl (PUI/NaOCl); conventional needle irrigation (CNI) + saline solution (CNI/SS); CNI + 1% NaOCl (CNI/NaOCl); No irrigation (control). Microbiological samples were collected at three time points: initial (21 days after inoculation), post-irrigation (immediately after irrigation), and final (7 days after irrigation). Data were obtained in CFU mL^-1 and subjected to analysis by ANOVA and Tukey's tests at 5% significance level. The post-irrigation samples did not demonstrate statistical difference between PUI/SS and CNI/SS nor between PUI/NaOCl and CNI/NaOCl (p>0.05), but PUI/NaOCl and CNI/NaOCl had lower CFU mL^-1 number than the other groups (p>0.05). Statistically significant difference was observed between the initial and post-irrigation samples and between the post-irrigation and final samples (p<0.05) in all groups, except in the control. The final samples of all groups presented bacterial counts similar to the initial samples. PUI or CNI with 1% NaOCl contribute to disinfection, but are unable to eradicate E. faecalis from the root canal system.

A irrigação endodôntica visa à limpeza e desinfecção do sistema de canais radiculares. A irrigação ultrassônica passiva (IUP) baseia-se na utilização de um instrumento ultrassônico ativado no interior do canal radicular preenchido com a solução irrigadora. O objetivo deste estudo foi avaliar, ex vivo, a eficácia da IUP na eliminação de Enterococcus faecalis dos canais radiculares. Foram usados 75 dentes humanos unirradiculares extraídos. Após o preparo biomecânico dos canais radiculares, foram inoculados com E. faecalis e incubados a 37 °C por 21 dias. Os espécimes foram distribuídos em cinco grupos (n=15), de acordo com o método de irrigação: IUP + solução salina (IUP/SS); IUP + NaOCl a 1% (IUP/NaOCl); irrigação manual convencional (IMC) + solução salina (IMC/sol); IMC + NaOCl a 1% (IMC/NaOCl); Sem irrigação (controle). Foram realizadas três coletas microbiológicas: inicial (21 dias após a inoculação), pós-irrigação (imediatamente após a irrigação), e final (7 dias após a irrigação). Os dados foram obtidos em UFC mL^-1 e submetidos aos testes de ANOVA e Tukey. A coleta pós-irrigação não demonstrou diferença estatisticamente significante entre IUP/SS e IMC/SS nem entre IUP/NaOCl e IMC/NaOCl (p>0,05), mas IUP/NaOCl e IMC/NaOCl apresentaram menor número de UFC mL^-1 comparado aos outros grupos (p>0,05). Diferença estatisticamente significante foi observada entre as coletas iniciais e pós-irrigação e entre a pós-irrigação e a coleta final (p<0,05) em todos os grupos, exceto no controle. Na coleta final, todos os grupos apresentaram contagem bacteriana similar à coleta inicial. IUP ou IMC com NaOCl a 1% contribuem para a desinfecção, mas não eliminam E. faecalis do sistema de canais radiculares.

Fracture resistance of teeth submitted to several internal bleaching protocols.

AIM: The aim of this study was to evaluate the fracture resistance of teeth submitted to several internal bleaching protocols using 35% hydrogen peroxide (35HP), 37% carbamide peroxide (37CP), 15% hydrogen peroxide with titanium dioxide nanoparticles (15HPTiO2) photoactivated by LED-laser or sodium perborate (SP). MATERIALS AND METHODS: After endodontic treatment, fifty bovine extracted teeth were divided into five groups (n = 10): G1-unbleached; G2-35HP; G3-37CP; G4-15HPTiO2 photoactivated by LED-laser and G5-SP. In the G2 and G4, the bleaching protocol was applied in 4 sessions, with 7 days intervals between each session. In the G3 and G5, the materials were kept in the pulp teeth for 21 days, but replaced every 7 days. After 21 days, the teeth were subjected to compressive load at a cross head speed of 0.5 mm/min, applied at 135° to the long axis of the root using an eletromechanical testing machine, until teeth fracture. The data were submitted to ANOVA and Tukey tests (α = 5%). RESULTS: The 35HP, 37CP, 15HPTiO2 and SP showed similar fracture resistance teeth reduction (p > 0.05). All bleaching treatments reduced the fracture resistance compared to unbleached teeth (p < 0.05). CONCLUSION: All bleaching protocols reduced the fracture resistance of endodontically-treated teeth, but there were no differences between each other. CLINICAL SIGNIFICANCE: There are several internal bleaching protocols using hydrogen peroxide in different concentrations and activation methods. This study evaluated its effects on fracture resistance in endodontically-treated teeth.

Fracture resistance of endodontically-treated teeth submitted to bleaching treatment with hydrogen peroxide and titanium dioxide nanoparticles photoactivated by LED-laser / Resistência à fratura de dentes tratados endodonticamente submetidos a tratamento clareador com peróxido de hidrogênio e nanopartículas de dióxido de titânio fotoativado por LED-laser

Objective: The aim of this study was evaluate the fracture resistance of endodontically-treated teeth after bleaching treatment using 15% hydrogen peroxide plus titanium dioxide nanoparticles (15HPTiO2) photoactivated by LED-laser, in comparison with protocols using 35% hydrogen peroxide (35HP), 37% carbamide peroxide (37CP) or sodium perborate (SP). Material and method: After endodontic treatment, fifty bovine extracted incisors were divided into five groups (n = 10): G1- without bleaching; G2- 35HP; G3- 37CP; G4- 15HPTiO2 photoactivated by LED-laser and G5- SP. In G2 and G4, the bleaching protocol was applied in 4 sessions, with a 7 day interval between each session. In G3 and G5, the materials were kept in the pulp chamber for 21 days, but replaced every 7 days. After 21 days, the crowns were subjected to compressive load at a cross head speed of 0.5 mm/min, applied at 135° to the long axis of the root using an eletromechanical testing machine, until fracture. The data were submitted to ANOVA and Tukey tests (p = 0.05). Result: The bleaching treatment in endodontically-treated teeth with 15HP plus TiO2 nanoparticles and photoactivated by LED-laser caused reduction of the fracture resistance similarly provided by 35HP, 37CP or SP (p>0.05). All bleaching treatments reduced the fracture resistance compared to unbleached teeth (p<0.05). Conclusion: All bleaching protocols reduced the fracture resistance of endodontically-treated teeth, but there were no differences between each other. .

Objetivo: Avaliar a resistência à fratura de dentes tratados endodonticamente após tratamento clareador usando peroxido de hidrogênio a 15% com nanopartículas de dióxido de titânio (15HPTiO2) fotoativado por LED-laser, em comparação aos protocolos usando peróxido de hidrogênio 35% (35HP), peróxido de carbamida 37% (37CP) ou perborato de sódio (SP). Material e método: Após tratamento endodôntico, 50 incisivos bovinos extraídos foram divididos em 5 grupos (n = 10): G1- sem clareamento; G2- 35HP; G3- 37CP; G4- 15HPTiO2 fotoativado por LED-laser e G5- SP. Nos grupos G2 e G4, o protocolo de clareamento foi aplicado em 4 sessões, com 7 dias de intervalo entre cada sessão. Nos grupos G3 e G5, os materiais foram inseridos na câmara pulpar por 21 dias e trocados a cada 7 dias. Após 21 dias, as coroas foram submetidas à força de compressão com velocidade de 0,5 mm/min, aplicada a 135º em relação ao longo eixo da raiz. empregando máquina de ensaios mecânicos, até a fratura. Os dados foram submetidos aos testes de ANOVA e Tukey (p = 0.05). Resultado: O tratamento clareador em dentes tratados endodonticamente com 15HP e nanopartículas de TiO2 fotoativado por LED-laser proporcionou redução da resistência à fratura semelhante ao 35HP, 37CP ou SP (p>0,05). Todos os tratamentos clareadores reduziram a resistência coronária à fratura quando comparados aos dentes sem tratamento (p<0,05). Conclusão: Todos os protocolos de clareamento reduziram a resistência à fratura dos dentes tratados endodonticamente, sem diferenças estatisticamente significantes entre os grupos. .

Antimicrobial activity of root canal irrigants associated with cetrimide against biofilm and planktonic Enterococcus faecalis.

AIM: To evaluate the antibacterial activity of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) alone or associated with cetrimide (CTR), and QMiX against biofilm and planktonic Enterococcus faecalis (E. faecalis) [American type culture collection (ATCC) 29212]. MATERIALS AND METHODS: The solutions 2.5% NaOCl, 2.5% NaOCl + 0.2% CTR, 2% CHX, 2% CHX + 0.2% CTR, 0.2% CTR, and QMiX were evaluated. E. faecalis biofilms were induced for 14 days on bovine dentin blocks. The irrigants were evaluated after contact with E. faecalis suspension and biofilm for 1 and 3 minutes. After that, serial decimal dilutions were made and plated on tryptic soy agar (TSA) medium. Plates were incubated for 24 hours at 37°C and the colony-forming unit (CFU) 1 ml was determined. Data were subjected to ANOVA and Tukey's tests at 5% significance. RESULTS: All microorganisms were eliminated by direct contact of the irrigants with planktonic cells. Only NaOCl and NaOCl + CTR were able to completely eliminate the microorganisms by direct contact with E. faecalis biofilm. CHX presented effectiveness similar to CHX + CTR CTR, and QMiX after 1 minute of contact and similar to NaOCl and NaOCl + CTR after 3 minutes (p > 0.05), but was unable to completely eliminate the microorganisms. CTR and QMiX did not differ from each other. CONCLUSION: CTR addition to CHX and NaOCl solutions did not improve the antimicrobial activity against biofilm. All evaluated irrigants and associations presented activity against planktonic E. faecalis. Only NaOCl and NaOCl + CTR eliminated biofilm after 1 and 3 minutes of direct contact.

Evaluation of the interaction between sodium hypochlorite and several formulations containing chlorhexidine and its effect on the radicular dentin--SEM and push-out bond strength analysis.

The aim of the current study was to evaluate the presence of debris and smear layer after endodontic irrigation with different formulations of 2% chlorhexidine gluconate (CHX) and its effects on the push-out bond strength of an epoxy-based sealer on the radicular dentin. One hundred extracted human canines were prepared to F5 instrument and irrigated with 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Fifty teeth were divided into five groups (n = 10), according to the final irrigation protocol with different 2% CHX formulations: G1 (control, no final rinse irrigation), G2 (CHX solution), G3 (CHX gel), G4 (Concepsis), and G5 (CHX Plus). In sequence, the specimens were submitted to scanning electron microscopy (SEM) analysis, in the cervical-medium and medium-apical segments, to evaluate the presence of debris and smear layer. The other 50 teeth were treated equally to a SEM study, but with the root canals filled with an epoxy-based endodontic sealer and submitted to a push-out bond strength test, in the cervical, middle, and apical thirds. G2, G3, G4, and G5 provided higher precipitation of the debris and smear layer than G1 (P < 0.05), but these groups were similar to each other (P > 0.05), in both segments. The values obtained in the push out test did not differ between groups, independent of the radicular third (P > 0.05). The CHXs formulations caused precipitation of the debris and smear layer on the radicular dentin, but these residues did not interfere in the push-out bond strength of the epoxy-based sealer.

Ethanol is inefficient to remove endodontic sealer residues of dentinal surface

Introduction: Endodontic sealer residues on dentinal surface have negative effects on adhesion of adhesives system and/or can cause discoloration of the dental crown. Objective: To evaluate the efficacy of 95% ethanol in removal of residues of epoxy-based (AH Plus), methacrylate-based (Epiphany SE) or calcium-based (Sealapex) sealers on dentinal surface. Material and methods: Thirty-two bovine incisor dental crown fragments (0.5 mm x 0.5 mm) were treated with 17% EDTA and 2.5% NaOCl. The specimens were divided into three experimental groups (n = 10): G1 (AH Plus), G2 (Epiphany SE) and G3 (Sealapex). In each group was applied a coating of one endodontic sealer type and were left undisturbed for 5 minutes. After this period, the specimens were cleaned with 95% ethanol. The control group was composed by two specimens that did not receive any sealer or cleaning treatment. The sealer residues persistence after cleaning with 95% ethanol was evaluated by scanning electron microscopy (x500) and a score system was applied. Data obtained were analyzed by Kruskal-Wallis and Dunn tests (α = 5%). Results: Moderate amount of endodontic sealer residues were observed in all groups, regardless of the endodontic sealer compositions. G1, G2 and G3 presented similar amount of sealer residues on dentinal surface after cleaning with 95% ethanol (p > 0.05). Conclusion: 95% ethanol was inefficiency to remove completely AH Plus, Epiphany SE and Sealapex residues of sealer-contaminated dentin.

Comparative analysis of Enterococcus faecalis biofilm formation on different substrates.

INTRODUCTION: The aim of this study was to compare Enterococcus faecalis biofilm formation on different substrates. METHODS: Cell culture plates containing growth medium and E. faecalis (ATCC 29212) were used to grow biofilm on bovine dentin, gutta-percha, hydroxyapatite, or bovine bone. Substrates were incubated at 37°C for 14 or 21 days, and the medium was changed every 48 hours. After the growth induction periods, specimens (n = 5 per group and per induction period) were stained by using Live/Dead, and the images were analyzed under a confocal microscope. The total biovolume (µm(3)), live bacteria biovolume (µm(3)), and substrate coverage (%) were quantified by using the BioImage_L software. Results obtained were analyzed by nonparametric tests (P = .05). RESULTS: Biofilm formation was observed in all groups. Gutta-percha had the lowest total biovolume at 14 days (P < .05) and hydroxyapatite the highest at 21 days (P < .05). No significant difference was observed in green biovolume at 14 days. At 21 days, however, hydroxyapatite had the highest volume (P < .05). The percentages of coverage were similar among all substrates at 21 days (P > .05), but at 14 days, bovine bone presented the highest coverage (P < .05). CONCLUSIONS: E. faecalis was capable of forming biofilm on all substrates during both growth periods; hydroxyapatite presented the highest rates of biofilm formation. The type of substrate influenced the biofilm characteristics, according to the parameters evaluated.

Persistence of resinous cement residues in dentin treated with different chemical removal protocols.

The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol-based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1--95% ethanol, G2--70% ethanol, G3--70% isopropyl alcohol, or G4--eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at × 500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal-Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups (P > 0.05), except between the eucalyptol and 70% ethanol groups (P < 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface.

Efficacy of NiTi rotary instruments in removing calcium hydroxide dressing residues from root canal walls.

THE AIM OF THIS STUDY: was to evaluate the efficacy of three rotary instrument systems (K3, ProTaper and Twisted File) in removing calcium hydroxide residues from root canal walls. Thirty-four human mandibular incisors were instrumented with the ProTaper System up to the F2 instrument, irrigated with 2.5% NaOCl followed by 17% EDTA, and filled with a calcium hydroxide intracanal dressing. After 7 days, the calcium hydroxide dressing was removed using the following rotary instruments: G1 - NiTi size 25, 0.06 taper, of the K3 System; G2 - NiTi F2, of the ProTaper System; or G3 - NiTi size 25, 0.06 taper, of the Twisted File System. The teeth were longitudinally grooved on the buccal and lingual root surfaces, split along their long axis, and their apical and cervical canal thirds were evaluated by SEM (×1000). The images were scored and the data were statistically analyzed using the Kruskall Wallis test. None of the instruments removed the calcium hydroxide dressing completely, either in the apical or cervical thirds, and no significant differences were observed among the rotary instruments tested (p > 0.05).

Efficacy of NiTi rotary instruments in removing calcium hydroxide dressing residues from root canal walls

The aim of this study was to evaluate the efficacy of three rotary instrument systems (K3, ProTaper and Twisted File) in removing calcium hydroxide residues from root canal walls. Thirty-four human mandibular incisors were instrumented with the ProTaper System up to the F2 instrument, irrigated with 2.5% NaOCl followed by 17% EDTA, and filled with a calcium hydroxide intracanal dressing. After 7 days, the calcium hydroxide dressing was removed using the following rotary instruments: G1 - NiTi size 25, 0.06 taper, of the K3 System; G2 - NiTi F2, of the ProTaper System; or G3 - NiTi size 25, 0.06 taper, of the Twisted File System. The teeth were longitudinally grooved on the buccal and lingual root surfaces, split along their long axis, and their apical and cervical canal thirds were evaluated by SEM (×1000). The images were scored and the data were statistically analyzed using the Kruskall Wallis test. None of the instruments removed the calcium hydroxide dressing completely, either in the apical or cervical thirds, and no significant differences were observed among the rotary instruments tested (p > 0.05).

Residues of calcium hydroxide-based intracanal medication associated with different vehicles: a scanning electron microscopy evaluation.

This study evaluated the presence of residues after removal of calcium hydroxide [Ca(OH)(2) ] associated with different vehicles. Thirty single-rooted teeth were instrumented to a master apical file #25 using 2.5% NaOCl as main irrigant and 17% trisodium EDTA (ethylenediaminetetraacetic acid) as final agent irrigant. Then, the root canals were dressed with Ca(OH)(2) associated with silicone oil (Group 1), 2% chlorhexidine gluconate (Group 2), or propylene glycol (Group 3). After coronal sealing, all teeth were kept in a moist environment at room temperature. After 7 days, the teeth were reopened and medicaments were removed using 5 mL of saline solution and instrumentation with master apical file followed by new irrigation with 5 mL of 2.5% NaOCl. Subsequently, teeth were split longitudinally and assessed by scanning electron microscopy. The wall cleanliness of the cervical and apical thirds of the roots were evaluated and scored by three blinded examiners. Statistical analysis was performed using Kruskal-Wallis and Wilcoxon tests at 5% level of significance. All roots had residues of Ca(OH)(2) on the canal walls. All experimental groups had similar results (P > 0.05) regardless of the third evaluated. There was significant difference between the apical and cervical thirds only in Group 3 (P < 0.05). Association of different vehicles to Ca(OH)(2) does not influence the persistence of residues on the root canal walls.

Antibacterial effectiveness of peracetic acid and conventional endodontic irrigants.

This study evaluated the in vitro antibacterial activity of conventional and experimental endodontic irrigants against Enterococcus faecalis. The following substances were evaluated by direct contact test: 2.5% sodium hypochlorite (NaOCl); 2% chlorhexidine (CHX); 1% peracetic acid. After different contact periods (30 s, 1, 3, and 10 min), a neutralizing agent was applied. Serial 10-fold dilutions were prepared and plated onto tryptic soy agar (TSA) and the number of colony-forming units per milliliter (CFU/mL) was determined. Sterile saline was used as a negative control. Both 2.5% NaOCl and 2% CHX eliminated E. faecalis after 30 s of contact. Peracetic acid reduced the bacterial counts by 86% after 3 min and completely eliminated E. faecalis after 10 min. These results allow us to conclude that 1% peracetic acid is effective against E. faecalis, despite its slower action compared with 2.5% NaOCl and 2% CHX.

Antibacterial efficacy of endodontic irrigating solutions and their combinations in root canals contaminated with Enterococcus faecalis.

OBJECTIVE: The objective of this study was to evaluate the antibacterial efficacy of irrigating solutions and their combinations against Enterococcus faecalis. STUDY DESIGN: One hundred ten single-rooted human teeth were inoculated with E. faecalis and incubated for 21 days. Teeth were divided according to the irrigant: Group I (GI), 2.5% sodium hypochlorite solution (NaOCl); GII, 2.5% NaOCl + 10% citric acid; GIII, 2.5% NaOCl + apple cider vinegar; GIV, apple cider vinegar; GV, 2% chlorhexidine solution; GVI, 1% peracetic acid; GVII, saline solution. Microbiological samples were taken after root canal preparation and 7 days later. Data were submitted to ANOVA (5%). RESULTS: All solutions promoted reduction of E. faecalis after instrumentation, but bacterial counts were higher in the final sample. GI, GV, and GVI had lower bacterial counts than the other groups. CONCLUSIONS: The irrigating solutions may present activity but do not eradicate E. faecalis in the root canal system.

Effectiveness of three solvents and two associations of solvents on gutta-percha and resilon.

This study evaluated the effectiveness of 3 solvents (Citrol orange oil, Eucalyptol and Tetrachloroethylene) and 2 associations of solvents (Citrol orange oil+Tetrachloroethylene and Eucalyptol+Tetrachloroethylene) on 3 types of gutta-percha (conventional, thermoplastic and EndoREZ) and Resilon. Ten discs (10 mm diameter x 1 mm thick) from each material were prepared using standard metallic molds. Each specimen was weighed to determinate its initial mass. The specimens were immersed in the solvents for 10 min, followed by immersion in distilled water for 20 min, and were then reweighed to obtain the final mass. The mean weight loss determined the solvent capacity. Data were analyzed by ANOVA and Tukey's test at 5% significance level. Tetrachloroethylene was the most effective on conventional gutta-percha (p<0.05). Tetrachloroethylene was also the most effective on thermoplastic gutta-percha, but it was not significantly different (p>0.05) from Eucalyptol+Tetrachloroethylene, Citrol+Tetrachloroethylene, and Citrol. All solvents and associations presented little effectiveness on Resilon. The association Eucalyptol+Tetrachloroethylene was the most effective on EndoREZ, but it did not differ significantly (p>0.05) from Citrol+Tetrachloroethylene and Tetrachloroethylene. All evaluated substances presented solvent action. Tetrachloroethylene improved the effectiveness of both Citrol and Eucalyptol.

Adaptação marginal do agregado de trióxido mineral com e sem cloreto de cálcio em retrocavidades / Marginal adaptation of the Mineral Trioxide Aggregate with and without calcium chloride in root-end cavities

Objetivo: Avaliar a adaptação marginal do Agregado de Trióxido Mineral (MTA) com e sem cloreto de cálcio (CaCl2) em retrocavidades. Método: Vinte dentes unirradiculados foram instrumentados e obturados com gutapercha e AH-Plus. Os ápices das raízes foram cortados com uma broca Zekrya e preparos retrógrados foram realizados com pontas ultrassônicas. Réplicas em resina dos ápices preparados foram obtidas, metalizadas com ouro e examinadas em microscopia eletrônica de varredura (MEV). Os espécimes foram divididos em dois grupos experimentais (n = 10 dentes), de acordo com o material retrobturador empregado: G1 ­ MTA e G2 ­ MTA + CaCl2. Após as retrobturações, os dentes foram mantidos em ambiente úmido a 37 °C por 24 horas. Novas réplicas de resina foram obtidas e levadas ao MEV. A adaptação marginal dos cimentos foi classificada como: 1) margem contínua; 2) margem não contínua. Além disso, os percentuais de margem contínua foram calculados. Os resultados foram analisados pelo teste de Mann-Whitney. Resultados: Falhas de adaptação foram observadas em duas raízes no G1 e três raízes no G2. O percentual de margem contínua foi de 95,59% no grupo com MTA e 87,48% no grupo com MTA + CaCl2 . Não houve diferença estatística significativa entre os dois grupos (p > 0,05). Conclusão: A adição do cloreto de cálcio ao MTA não alterou a sua capacidade de adaptação marginal às paredes dentinárias das retrocavidades.

Objective: To evaluate the marginal adaptation of the Mineral Trioxide Aggregate (MTA) with and without calcium chloride (CaCl2) in root-end cavities. Method: Twenty extracted single-rooted teeth were instrumented and obturated with gutta-percha and AH Plus. All roots were resected using a Zekrya bur and root-end cavities were prepared by using ultrasonic retrotips. Epoxy resin replicas of root-end surfaces after root-end cavity preparation were obtained, sputter coated with gold, and examined by using a scanning electron microscope (SEM). The sampleswere divided into two experimental groups (n = 10 teeth) according to the root-end filling material employed: G1 - MTA; and G2 - MTA + CaCl2. After the root-end filling, the teeth were stored in moist gauze at 37 °C for24 hours. New replicas of the root-end surfaces were obtained and examined under a SEM. Marginal adaptation of the filling materials were categorized as: 1) continuous margin; 2) non-continuous margin. Besides, percentages of continuous margin were calculated. The results were analyzed by the Mann-Whitney test. Results: Visible gaps were seen in 2 roots in G1 and in 3 roots in G2. A continuous margin was observed with 95,59% of MTA and 87,48% of MTA + CaCl2 root-end fillings. There was not statistical difference between the two groups (p > 0.05).Conclusion: The addition of CaCl2 to MTA did not alter its marginal adaptation capability to the dentin walls of root-end cavities.

Previsibilidade de implantes curtos: revisão de literatura / Predictability of short dental implants: a literature review

Introdução: Nas situações clínicas em que ocorre severa reabsorção óssea após perda de dentes, as opções de tratamento com implantes incluem a necessidade de reconstrução óssea prévia e instalação de implantes convencionais ou apenas de implantes curtos. Objetivo: Revisar não sistematicamente a literatura com o propósito de sintetizar e discutir alguns itens sobre o uso de implantes curtos, tais como aspectos biomecânicos, índices de sucesso, longevidade e planejamento cirúrgico-protético. Revisão de literatura: Buscou-se selecionar referências atuais e de impacto acerca dos implantes curtos, comparando-os aos convencionais. Diversos estudos destacam a maior importância do diâmetro dos implantes. Para a prática clínica os curtos apresentam altas taxas de sucesso e previsibilidade quando determinados aspectos biomecânicos são levados em consideração. Conclusão: A colocação de implantes curtos torna-se um tratamento viável para pacientes com altura óssea reduzida.

Introduction: In clinical situations where severe bone resorption has occurred following tooth loss, implant treatment options may comprise either a previous bone reconstruction or only the use of short implants. Objective: This non-systematic review summarizes and discusses some aspects of the use of short implants, such as: biomechanical aspects, success rate, longevity and surgical-prosthetic planning. Literature review: Current and relevant references were selected in order to compare short dental implants to conventional ones. Several studies have highlighted the great importance of wide-diameter implants. Dental short implants have shown high predictability and success rates when some biomechanical aspects are taken into consideration. Conclusion: Placement of short dental implants is a viable treatment method for patients with decreased bone height.

Antibacterial effectiveness of peracetic acid and conventional endodontic irrigants

This study evaluated the in vitro antibacterial activity of conventional and experimental endodontic irrigants against Enterococcus faecalis. The following substances were evaluated by direct contact test: 2.5 percent sodium hypochlorite (NaOCl); 2 percent chlorhexidine (CHX); 1 percent peracetic acid. After different contact periods (30 s, 1, 3, and 10 min), a neutralizing agent was applied. Serial 10-fold dilutions were prepared and plated onto tryptic soy agar (TSA) and the number of colony-forming units per milliliter (CFU/mL) was determined. Sterile saline was used as a negative control. Both 2.5 percent NaOCl and 2 percent CHX eliminated E. faecalis after 30 s of contact. Peracetic acid reduced the bacterial counts by 86 percent after 3 min and completely eliminated E. faecalis after 10 min. These results allow us to conclude that 1 percent peracetic acid is effective against E. faecalis, despite its slower action compared with 2.5 percent NaOCl and 2 percent CHX.

Este estudo avaliou, in vitro, a atividade antibacteriana de soluções irrigadoras convencionais e experimentais sobre Enterecoccus faecalis. As seguintes substâncias foram avaliadas por teste de contato direto: hipoclorito de sódio (NaOCl) a 2,5 por cento, clorexidina (CHX) a 2 por cento, ácido peracético a 1 por cento. Após diferentes períodos de contato (30 s, 1, 3 e 10 min), um agente neutralizante foi empregado. Diluições decimais seriadas foram realizadas e semeadas em placas de tryptic soy agar (TSA). O número de unidades formadoras de colônia por mililitro (UFC/mL) foi determinado. Solução salina foi utilizada como controle negativo. Ambos, NaOCl a 2,5 por cento e CHX a 2 por cento, eliminaram E. faecalis após 30 s de contato. O ácido peracético reduziu a contagem bacteriana em 86 por cento após 3 min e eliminou completamente E. faecalis após 10 min. Estes resultados permitem concluir que o ácido peracético a 1 por cento é efetivo sobre E. faecalis, apesar de sua ação mais lenta quando comparado ao NaOCl a 2,5 por cento e CHX a 2 por cento.

Effectiveness of three solvents and two associations of solvents on gutta-percha and resilon

This study evaluated the effectiveness of 3 solvents (Citrol orange oil, Eucalyptol and Tetrachloroethylene) and 2 associations of solvents (Citrol orange oil+Tetrachloroethylene and Eucalyptol+Tetrachloroethylene) on 3 types of gutta-percha (conventional, thermoplastic and EndoREZ) and Resilon. Ten discs (10 mm diameter x 1 mm thick) from each material were prepared using standard metallic molds. Each specimen was weighed to determinate its initial mass. The specimens were immersed in the solvents for 10 min, followed by immersion in distilled water for 20 min, and were then reweighed to obtain the final mass. The mean weight loss determined the solvent capacity. Data were analyzed by ANOVA and Tukey's test at 5 percent significance level. Tetrachloroethylene was the most effective on conventional gutta-percha (p<0.05). Tetrachloroethylene was also the most effective on thermoplastic gutta-percha, but it was not significantly different (p>0.05) from Eucalyptol+Tetrachloroethylene, Citrol+Tetrachloroethylene, and Citrol. All solvents and associations presented little effectiveness on Resilon. The association Eucalyptol+Tetrachloroethylene was the most effective on EndoREZ, but it did not differ significantly (p>0.05) from Citrol+Tetrachloroethylene and Tetrachloroethylene. All evaluated substances presented solvent action. Tetrachloroethylene improved the effectiveness of both Citrol and Eucalyptol.

Este estudo avaliou a efetividade de 3 solventes (Citrol, Eucaliptol e Tetracloroetileno) e 2 associações (Citrol+Tetracloroetileno e Eucaliptol+Tetracloroetileno) sobre 3 tipos de guta-percha (convencional, termoplástica e EndoREZ) e Resilon. Dez discos (10 mm x 1 mm) de cada material foram preparados utilizando moldes metálicos. Cada espécime foi pesado para determinar a massa inicial. Os mesmos foram imersos nas soluções testadas por 10 min e em água destilada por 20 min. Os espécimes foram novamente pesados, agora para determinar a massa final. A perda média de peso determinou a capacidade solvente. Os dados foram analisados pelos testes ANOVA e Tukey. O tetracloroetileno foi o mais efetivo sobre a guta-percha convencional (p<0,05). Ele também foi o mais efetivo sobre a guta-percha termoplástica, mas sem diferença significativa para o Eucaliptol+Tetracloroetileno, Citrol+Tetracloroetileno e o Citrol (p>0,05). Todos os solventes e associações apresentaram pequena ação sobre o Resilon. A associação Eucaliptol+Tetracloroetileno obteve o melhor resultado sobre o EndoREZ, mas sem diferença significativa para o Citrol+Tetracloroetileno e o Tetracloroetileno (p>0,05). Todas as soluções apresentam ação solvente. O Tetracloroetileno melhorou a efetividade do Citrol e do Eucaliptol.