Current trends in technological armamentarium and treatment among Brazilian endodontists

Aim: To determine the current trends in technological armamentarium and endodontic treatment among Brazilian endodontists. Methods: A total of 279 endodontists answered a web-based survey questionnaire about their region of activity in Brazil and years as a specialist, average number of endodontic cases treated per month, number of visits to complete the treatment, use of rubber dam for isolation, type of irrigant, obturation technique and device used for this purpose, temporary filling materials, and greater difficulty encountered during treatment and technological armamentarium. A descriptive analysis, expressed in terms of frequency and percentage, was performed and the data were correlated using the chi-square test (p<0.05). Results: Most of the respondents had up to 10 years as specialists. More than 50% of endodontists preferred to complete the endodontic treatment in a single visit. Ninety-nine percent of endodontists used rubber dam for isolation. NaOCl was the most widely used irrigant. Most of the respondents associated different techniques for root canal filling. Lateral condensation and Continuous wave of condensation were the isolated technique most reported. Filling devices (thermocompactors) were used by 53% of endodontists. Glass ionomer was the preferred temporary filling material. The answers for the use of technological armamentarium revealing that 94% of endodontists used an apex locator; 67.38% utilized magnification (loupe: 23.66%; microscope: 35.48%; microscope and loupe: 8.24%); 58% reported to digital radiography; and 47.31% used computed tomography as a complementary tool. About mechanized instrumentation, 44.44% endodontists employed rotary and reciprocating files. The difficulties encountered during endodontic treatment were classified as preparation > access > obturation > anesthesia > isolation. Conclusions: Most endodontists have implemented new technologies, such as mechanical instrumentation, apex locators, magnification, digital radiography, computed tomography, ultrasound, and obturation tools, in their clinical practice (AU)

Investigation in vivo of Enterococcus faecalis in endodontic retreatment by phenotypic and genotypic methods / Investigação in vivo de Enterococcus faecalis em retratamento endodôntico por meio de métodos fenotípicos e genotípicos

This study aimed to investigate the prevalence of E. faecalis in root-filled canals using culture and molecular approaches. It was evaluated the antimicrobial susceptibility to different antibiotics and the virulence factors of E. faecalis isolates. Microbial samples were taken from thirty root-filled canals. Culture methods and 16S rDNA assay were used to identify E. faecalis. The antimicrobial susceptibility of E. faecalis was determined by MIC values using the E test. Cultivable strains of E. faecalis were investigated for virulence factors by PCR technique. E. faecalis were detected by culture (7/30), traditional PCR assay (13/30) and nested PCR (23/30). Both PCR were significantly more effective than culture in detecting E. faecalis (p < 0.05). All tested E. faecalis were highly sensitive to amoxicillin. Some strains of E. faecalis were resistant to antibiotics such as rifampicin (4/12), erythromycin (3/12) and azythromycin (8/12). The genes efaA and ace were detected in all isolates. The other virulence genes were found in 91.6 (gelE), 83.3 (asa), 25 (esp) and 16.6% (cylA). Strains of E. faecalis isolated from root-filled canals showed virulence factors related to adherence. They also showed resistance to some antibiotics commonly used in dentistry.

O objetivo deste estudo foi investigar a prevalência de E. faecalis em dentes tratados endodonticamente utilizando as técnicas de cultura e molecular. Foram avaliados a suscetibilidade antimicrobiana frente a diferentes antibióticos e os fatores de virulência de E. faecalis isolados. As amostras foram coletadas de 30 dentes tratados endodonticamente. Métodos de cultura e 16S rDNA foram utilizados para identificar E. faecalis. A suscetibilidade antimicrobiana de E. faecalis foi determinada por valores de MIC, utilizando o E test. Os fatores de virulência de cepas de E. faecalis cultiváveis foram investigados pela técnica de PCR. E. faecalis foram detectados por cultura (7/30), PCR tradicional (13/30) e nested PCR (23/30). Ambas as técnicas de PCR foram significativamente mais eficazes do que a cultura na detecção de E. faecalis (p < 0,05). Todos os E. faecalis testados foram altamente sensíveis à amoxicilina. Algumas cepas de E. faecalis foram resistentes a antibióticos, como a rifampicina (4/12), eritromicina (3/12) e azitromicina (8/12). Os fatores de virulência efaA e ace foram detectados em todos os isolados. Os outros genes de virulência foram encontrados em 91,6 (gelE), 83,3 (asa), 25 (esp) e 16,6% (cylA). As cepas de E. faecalis isoladas em dentes tratados endodonticamente mostraram fatores de virulência relacionados à adesão. Eles também apresentaram resistência a alguns antibióticos comumente utilizados na odontologia.

Prevalence of Treponema spp. in endodontic retreatment-resistant periapical lesions.

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum (3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium (2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskii and T. denticola, and between T. maltophilum and T. lecithinolyticum . No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponema spp. are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure.

Prevalence of Treponemaspp. in endodontic retreatment-resistant periapical lesions

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum(3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium(2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskiiand T. denticola,and between T. maltophilumand T. lecithinolyticum. No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponemaspp.are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure.

Eficácia das limas manuais e do sistema MTwo R na redução bacteriana em dentes tratados endodonticamente com lesão periapical crônica / Effectiveness of hand files and the MTwo R system in bacterial reduction in endodontically treated teeth with chronic apical periodontitis

Objetivo: o objetivo desse estudo foi comparar, in vivo,a eficácia de duas técnicas para remoção da guta-percha(limas manuais e o sistema MTwo R) na redução microbianaapós o preparo químico-mecânico em dentes tratadosendodonticamente e com lesão periapical crônica.Material: trinta dentes unirradiculares obturados, comlesão periapical crônica, foram divididos em dois grupos.Um grupo teve a remoção da guta-percha por meiode limas manuais (n = 15), enquanto o outro grupo utilizouas limas rotatórias MTwo R (n = 15). Após a remoçãoda guta-percha, a primeira amostra (S1) foi obtida.Em seguida, foi realizado o preparo químico-mecânico euma segunda coleta (S2). A carga bacteriana foi determinadapor meio da técnica de cultura. Aplicou-se ostestes estatísticos de Wilcoxon e de Mann-Whitney. Resultados:em S1, todos os canais mostraram a presençabacteriana nos grupos manual e MTwo R, com medianade 5,14 x 103 (variação 20-1,7 x 105) e 3,4 x 102 (variação20-3,14 x 103), respectivamente. Em S2, a redução bacterianafoi detectada nos dois grupos (p < 0,05). Conclusão:conclui-se que o MTwo R mostrou significativaredução bacteriana durante o retratamento endodôntico.

Beta-lactamic resistance profiles in Porphyromonas, Prevotella, and Parvimonas species isolated from acute endodontic infections.

INTRODUCTION: Susceptibility to beta-lactamic agents has changed among anaerobic isolates from acute endodontic infections. The aim of the present study was to determine the prevalence of the cfxA/cfxA2 gene in Prevotella spp., Porphyromonas spp., and Parviomonas micra strains and show its phenotypic expression. METHODS: Root canal samples from teeth with acute endodontic infections were collected and Porphyromonas, Prevotella, and Parvimonas micra strains were isolated and microbiologically identified with conventional culture techniques. The susceptibility of the isolates was determined by the minimum inhibitory concentration of benzylpenicillin, amoxicillin, and amoxicillin + clavulanate using the E-test method (AB BIODISK, Solna, Sweden). The presence of the cfxA/cfxA2 gene was determined through primer-specific polymerase chain reaction. The nitrocefin test was used to determine the expression of the lactamase enzyme. RESULTS: Prevotella disiens, Prevotella oralis, Porphyromonas gingivalis, and P. micra strains were susceptible to benzylpenicillin, amoxicillin, and amoxicillin + clavulanate. The cfxA/cfxA2 gene was detected in 2 of 29 isolates (6.9%). Simultaneous detection of the cfxA/cfxA2 gene and lactamase production was observed for 1 Prevotella buccalis strain. The gene was in 1 P. micra strain but was not expressed. Three strains were positive for lactamase production, but the cfxA/cfxA2 gene was not detected through polymerase chain reaction. CONCLUSIONS: There is a low prevalence of the cfxA/cfxA2 gene and its expression in Porphyromonas spp., Prevotella spp., and P. micra strains isolated from acute endodontic infections. Genetic and phenotypic screening must be performed simultaneously to best describe additional mechanisms involved in lactamic resistance for strict anaerobes.

Culture and molecular detection of Enterococcus faecalis from patients with failure endodontic treatment and antimicrobial susceptibility of clinical isolates / Cultura e detecção molecular de Enterococcus faecalis de pacientes com insucesso no tratamento endodôntico e suscetibilidade antimicrobiana dos isolados clínicos

Objective: The aim of this study was to evaluate the minimal inhibitory concentrations (MIC) of different antibiotic agents against to the most prevalent microorganism found in root-filled canals by culture and molecular approaches. Material and Methods: The microbial samples were taken either from thirty root-filled canals after removal of gutta-percha. Culture methods and 16s rDNA assay were used to identify the E faecails present in the samples. The antimicrobial susceptibilities of the isolates of E faecalis were determined by MIC values using the E test System and interpreted according to the Clinical and Laboratory Standards Institute guidelines. The following antibiotics were used: benzylpenicillin, amoxicillin, amoxicillin-clavulanic acid, erythromycin, azithromycin, vancomycin, chloramphenicol, tetracycline, doxycycline, ciprofloxacin, rifampicin and moxifloxacin. Results: E faecalis were isolated (7/30) and detected (13/30) by culture and PCR assay, respectively. All tested E faecalis (n = 12) were highly sensitive to amoxicillin, moxifloxacin, vancomycin, benzylpenicillin and amoxicillin-clavulanic acid. Isolated E faecalis strains were resistant to some antibiotics such as rifampicin (4/12), tetracycline (2/12), doxycycline (1/12), erythromycin (3/12) and azythromycin (8/12). Conclusion: Amoxicillin, amoxicillin-clavulanic acid, benzylpenicillin, vancomycin and moxifloxacin were the most active antibiotics, in vitro, against E faecalis clinical strains, with all the isolates being susceptible Azithromycin and erythromycin were least effective, with none percentage of isolates being susceptible, during laboratory testing. Moreover, E faecalis were identified more frequently by PCR assay than by culture technique.

Objetivo: O objetivo deste estudo foi avaliar as concentrações inibitórias mínimas (CIM) de diferentes antibióticos contra micro-organismos mais prevalentes em canais radiculares pelos métodos moleculares e de cultura. Material e Métodos: As amostras microbianas foram obtidas de trinta canais radiculares após a remoção da gutapercha. Os métodos de cultura e ensaio 16s rDNA foram utilizados para identificar E. faecalis presente nas amostras. As susceptibilidades antimicrobianas dos isolados de E. faecalis foram determinadas pelos valores de CIM utilizando o sistema E teste e interpretados de acordo com as diretrizes CLSI(Clinical and Laboratory Standards Institute). Foram utilizados os seguintes antibióticos: benzilpenicilina, amoxicilina, amoxicilina com ácido clavulânico, eritromicina, azitromicina, vancomicina, cloranfenicol, tetraciclina, doxiciclina, ciprofloxacina, moxifloxacina e rifampicina. Resultados: E. faecalis foram isolados (7/30) e detectados (13/30) por cultura e pelo método PCR, respectivamente. Todos E. faecalis (n = 12) foram altamente sensíveis à amoxicilina,moxifloxacina,vancomicina, benzilpenicilina e amoxicilina com ácido clavulânico. Cepas isoladas de E. faecalis foram resistentes a alguns antibióticos como a rifampicina (4/12), tetraciclina (2/12), doxiciclina (1/12), eritromicina (3/12) e azitromicina (8/12). Conclusão: Amoxicilina, amoxicilina com ácido clavulânico, benzilpenicilina, vancomicina e moxifloxacina foram os antibióticos mais ativos, in vitro, contra cepas clínicas de E. faecalis, com todos os isolados sendo suscetíveis. Azitromicina e eritromicina foram menos eficazes, com nenhuma porcentagem de isolados suscetível durante os testes laboratoriais. E ainda, E. faecalis foram identificados mais frequentemente pela técnica PCR do que pela técnica de cultura.

Investigation of cultivable bacteria isolated from longstanding retreatment-resistant lesions of teeth with apical periodontitis.

INTRODUCTION: The objective of this research was to investigate the presence of viable bacteria in tissue samples from persistent apical lesions and to correlate the microbiological findings with the histopathological diagnosis of the lesion. METHODS: Twenty persistent apical lesions associated with well-performed endodontic retreatment were collected. Tissue samples were processed through culture techniques including serial dilution, plating, aerobic and anaerobic incubation, and biochemical tests for microbial identification followed by histopathological diagnosis. RESULTS: Cysts were more frequently diagnosed (13/20). Strict anaerobic species predominated in both cysts (80.4% of the species detected) and granulomas (65% of the species detected). Viable gram-positive bacteria were frequently recovered from apical lesions (cysts = 70.6%, granulomas = 84.4%). Gemella morbillorum and Propionibacterium acnes were the most frequently recovered species from cysts and granulomas, respectively. At least 1 gram-positive bacterial species was present in almost every sample (cysts = 12/13, granulomas = 7/7). No significant correlation was found between histologic findings and bacterial species. CONCLUSIONS: In conclusion, although cysts were more frequent than granulomas in cases of failure of endodontic retreatment, bacteria were isolated from both types of lesions, with a predominance of gram-positive species, suggesting that these species can survive outside the root canal and might be related to the persistence of the pathological process even after accurate endodontic retreatment.

Clustering behavior in microbial communities from acute endodontic infections.

INTRODUCTION: Acute endodontic infections harbor heterogeneous microbial communities in both the root canal (RC) system and apical tissues. Data comparing the microbial structure and diversity in endodontic infections in related ecosystems, such as RC with necrotic pulp and acute apical abscess (AAA), are scarce in the literature. The aim of this study was to examine the presence of selected endodontic pathogens in paired samples from necrotic RC and AAA using polymerase chain reaction (PCR) followed by the construction of cluster profiles. METHODS: Paired samples of RC and AAA exudates were collected from 20 subjects and analyzed by PCR for the presence of selected strict and facultative anaerobic strains. The frequency of species was compared between the RC and the AAA samples. A stringent neighboring clustering algorithm was applied to investigate the existence of similar high-order groups of samples. A dendrogram was constructed to show the arrangement of the sample groups produced by the hierarchical clustering. RESULTS: All samples harbored bacterial DNA. Porphyromonas endodontalis, Prevotella nigrescens, Filifactor alocis, and Tannerela forsythia were frequently detected in both RC and AAA samples. The selected anaerobic species were distributed in diverse small bacteria consortia. The samples of RC and AAA that presented at least one of the targeted microorganisms were grouped in small clusters. CONCLUSIONS: Anaerobic species were frequently detected in acute endodontic infections and heterogeneous microbial communities with low clustering behavior were observed in paired samples of RC and AAA.

Persistent extraradicular infection in root-filled asymptomatic human tooth: scanning electron microscopic analysis and microbial investigation after apical microsurgery.

INTRODUCTION: Procedural accidents have a negative effect on healing and might contribute to the persistence of infections in inaccessible apical areas, requiring surgical intervention. This report describes a case of persistent apical periodontitis of a lower left first molar associated with the sinus tract and a periapical lesion that required nonsurgical endodontic retreatment and apical surgery for resolution. METHODS: The tooth had received endodontic treatment 3 years ago and had to be retreated using the crown-down technique with chemical auxiliary substance (2% chlorhexidine gel), foramen patency, and enlargement and was filled in a single appointment. The occlusal access cavity was immediately restored with composite resin. After 1 month, it could be observed that the sinus tract persisted and, radiographically, the lesion remained unaltered. Therefore, endodontic microsurgery was indicated. Apical microsurgery was performed under magnification with the use of a dental operating microscope including apicectomy, root end with ultrasound, and sealing with mineral trioxide aggregate. A microbiological sample was collected from the apical lesion. The resected distal root apex was observed by scanning electron microscopy. RESULTS: The following species were detected: Actinomyces naeslundii and Actinomyces meyeri, Propionibacterium propionicum, Clostridium botullinum, Parvimonas micra, and Bacteroides ureolyticus; scanning electron microscopic analysis revealed bacterial biofilm surrounding the apical foramen and external radicular surface. Gutta-percha overfilling at the apex because of a zip caused during initial endodontic treatment could be observed. A 6-month follow-up showed apparent radiographic periapical healing, which progressed after 24 months. CONCLUSION: Gram-positive anaerobic bacteria and extraradicular biofilm seem to participate in the maintenance of persistent periapical pathology, and endodontic retreatment followed by periapical microsurgery proved to be a successful alternative in the resolution of persistent extraradicular infections.

Influence of 2% chlorhexidine gel on calcium hydroxide ionic dissociation and its ability of reducing endotoxin.

OBJECTIVE: The aim of this study was to evaluate the influence of 2% chlorhexidine gel (CHX) on pH, calcium release, and Ca(OH)(2) capability of reducing endotoxin. STUDY DESIGN: Calcium release was verified by atomic-absorbance spectrophotometry, and pH was measured with a pHmeter. For endotoxin quantification, extracted human teeth previously contaminated with standard endotoxin were filled with: group I, Ca(OH)(2) + saline solution; group II, Ca(OH)(2) + CHX; and group III, CHX for 14 days. The remaining endotoxin was quantified by using chromogenic quantitative test. Statistical analysis was performed with analysis of variance and Tukey post hoc test (P < .05). RESULTS: Group II released more calcium than group I (P < .05) after 15 days. Groups I and II showed alkaline pH in all periods, and group I showed higher pH values than group II (P < .05) after 30 days. Groups II and III showed significantly more decreased endotoxin than group I. CONCLUSIONS: CHX did not interfere with the chemical properties of Ca(OH)(2), in fact even improving its properties of reducing the endotoxin content in root canals in vitro.

Treponema species detected in infected root canals and acute apical abscess exudates.

INTRODUCTION: Different microbial communities have been associated with acute endodontic infections. The majority of the microorganisms are as yet uncultivable or difficult to grow under current laboratory conditions. Treponema species are strict anaerobic bacteria that are involved in several oral diseases. The aim of this study was to detect the presence of Treponema species in infected root canals (RCs) and exudates related to acute apical abscesses (AAAs) as well as to determine positive association between targeted species and clinical signs/symptoms. METHODS: Paired samples of infected RCs and AAAs were collected from 20 subjects. Nested polymerase chain reaction assay with species-specific primers for 16S rDNA and downstream intergenic spacer region was used for microbial detection. The frequency of species and statistical associations between species and signs/symptoms of endodontic origin as well as their simultaneous detection in both milieus were investigated. RESULTS: The most frequently detected species were T. socranskii (RC, 17/20; AAA, 15/20), T. denticola (RC, 8/20; AAA, 11/20); T. medium (RC, 6/20; AAA, 9/20); and T. amylovorum (RC, 5/20; AAA, 9/20). Positive correlation was found for simultaneous presence of T. denticola in both RCs and AAAs (p = 0.01). Positive association was observed between T. medium and T. vincentii (p = .037). No positive statistical association was observed between the targeted species and signs/symptoms. CONCLUSIONS: The high incidence of Treponema species in RC and AAA samples from the same tooth indicated that they are important pathogens in acute endodontic infections.

Frequency, microbial interactions, and antimicrobial susceptibility of Fusobacterium nucleatum and Fusobacterium necrophorum isolated from primary endodontic infections.

This study assessed the prevalence and microbial interactions of Fusobacterium nucleatum and Fusobacterium necrophorum in primary endodontic infections from a Brazilian population and their antimicrobial susceptibility to some antibiotics by the E-test. One hundred ten samples from infected teeth with periapical pathologies were analyzed by culture methods. Five hundred eighty individual strains were isolated; 81.4% were strict anaerobes. F. nucleatum was found in 38 root canals and was associated with Porphyromonas gingivalis, Prevotella spp., and Eubacterium spp. F. necrophorum was found in 20 root canals and was associated with Peptostreptococcus prevotii. The simultaneous presence of F. nucleatum and F. necrophorum was not related to endodontic symptoms (p > 0.05). They were 100% susceptible to amoxicillin, amoxicillin/clavulanate, and cephaclor. Fusobacterium spp. is frequently isolated from primary-infected root canals of teeth with periapical pathologies. Amoxicillin is a useful antibiotic against F. nucleatum and F. necrophorum in endodontic infections and has been prescribed as the first choice in Brazil.