Marcos Sergio Endo

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.

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

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

Quantitative and qualitative analysis of microorganisms in root‑filled teeth with persistent infection: Monitoring of the endodontic retreatment

Objective: The aim of this study was to investigate in vivo microorganisms detected in root-filled teeth with post-treatment apical periodontitis and quantify colony-forming units (CFU) during endodontic retreatment. Materials and Methods: Fifteen root-filled teeth had their previous gutta-percha removed and were randomly instrumented before being divided into three groups and medicated with either [Ca (OH) 2 + 2% CHX gel], [Ca (OH) 2 + 0.9% NaCl] or 2% CHX gel. Samples were taken after removal of gutta-percha (S1), after chemomechanical preparation using 2% CHX gel (S2), and after inter-appointment dressing (S3) for 7 or 14 days later. Cultivable bacteria recovered from infected root canals at the three stages were counted and identified by means of culture and PCR assay (16S rDNA). Quantitative data were statistically analyzed by using Mann-Whitney test in which pairs of groups were compared (P < 0.05). Results: CFU counts decreased significantly from S1 to S2 (P < 0.05). No significant difference was found between S2 and S3 (P = 0.3093) for all three experimental groups. Chemomechanical preparation and intra-canal dressing promoted significant median reductions of 99.61% and 99.57%, respectively, in the number of bacteria compared to S1 samples. A total of 110 cultivable isolates were recovered by culture technique from 32 different species and 7 different genera. Out of the 13 target species-specific primer of bacteria analyzed, 11 were detected during endodontic retreatment. Conclusion: The great majority of taxa found in post-treatment samples were Gram-positive bacteria, although Gram-negative bacteria were found by molecular methods. Moreover, our results showed that gutta-percha removal and chemomechanical preparation are effective for root canal disinfection, whereas additional intra-canal dressing did not improve disinfection.

Capsule Locus Polymorphism among Distinct Lineages of Enterococcus faecalis Isolated from Canals of Root-filled Teeth with Periapical Lesions

INTRODUCTION Although Enterococcus faecalis is a member of the normal microbiota, it is also a major cause of nosocomial infections. Some strains of E. faecalis produce capsule, which contributes to pathogenesis through evasion of host defenses, and its production is dependent on the capsule (cps) operon polymorphism. This study investigated cps locus polymorphism in distinct lineages of E. faecalis isolated from canals of root-filled teeth with periapical lesions. METHODS Twenty-two E. faecalis isolates were evaluated regarding the cps operon polymorphism and genetic diversity. The 3 known CPS types were determined by polymerase chain reaction. This information was correlated with multilocus sequence typing data, which were used to define genetic lineages. RESULTS cpsA and cpsB were the only detected genes within the cps operon in 62.5% of E. faecalis strains (14/22), indicative of genotype CPS 1, which lacks capsule expression. The essential genes in the cps operon for capsule production were detected in the remaining strains, whereas 3 belonged to genotype CPS 5 and 5 strains to genotype CPS 2. A total of 14 sequence types (STs) were resolved in 22 E. faecalis isolates. Comparison with the E. faecalis international multilocus sequence typing database revealed that 9 STs were previously found, and that the 5 STs were novel. CONCLUSIONS Certain E. faecalis genotypes from canals of root-filled teeth with periapical lesions belong to lineages associated with capsule expression and production of multiple virulence factors, which might account for their increased pathogenic potential.

Comparison of Fusobacterium nucleatum and Porphyromonas gingivalis Lipopolysaccharides Clinically Isolated from Root Canal Infection in the Induction of Pro- Inflammatory Cytokines Secretion

The aim of this study was to compare the biological activity of lipopolysaccharides (LPS) purified from Fusobacterium nucleatum and Porphyromonas gingivalis strains, both isolated from primary endodontic infection (PEI) in the levels of IL-1β and TNF-α released by macrophage cells. Moreover, LPS was purified from F. nucleatum and P. gingivalis American Type Collection (ATCC) and its biological activity was compared to respectively clinical isolates strains. F. nucleatum and P. gingivalis strains clinically isolated from PEI had their identification confirmed by sequencing the 16S rRNA gene. LPS from F. nucleatum and P. gingivalis and their respective ATCC strains were extracted by using Tri-reagent method. Macrophages (Raw 264.7) were stimulated with LPS at 100 ng/mL for 4, 8 and 12 h. Secretion of IL-1 β and TNF-α was also determined. Paired t-test, repeated measures ANOVA and one-way ANOVA were employed. All LPS induced significant production of IL-1β and TNF-α, with the former being secreted at higher levels than the latter in all time-points. F. nucleatum induced a higher expression of both cytokines compared to P. gingivalis (p<0.05). No differences were observed between clinical and ATCC strains, as both presented the same potential to induce pro-inflammatory response. It was concluded that F. nucleatum and P. gingivalis LPS presented different patterns of activation against macrophages as seen by the IL-1β and TNF-α production, which may contribute to the immunopathogenesis of apical periodontitis. Moreover, clinical and ATCC strains grown under the same in vitro environment conditions presented similar biological activity.

Medicação intracanal sem trocas periódicas como tratamento de dente avulsionado: relato de caso

Posteriormente ao reimplante de dentes avulsionados existe a necessidade da realizacao do tratamento endodontico o mais breve possivel em casos diagnosticados com necrose pulpar. O protocolo de tratamento de dentes avulsionados envolve o uso de medicacao intracanal a base de hidroxido de calcio, entre sessoes, como um fator complementar a reducao de micro-organismos, prevencao e estabilizacao da reabsorcao radicular, inducao de formacao dentinaria e reparo dos tecidos periapicais. O objetivo deste trabalho e apresentar e discutir um protocolo de tratamento frente a reabsorcao radicular externa causado posteriormente ao reimplante de um dente avulsionado, por meio do uso de uma medicacao intracanal sem a necessidade de trocas periodicas. Paciente do genero masculino, 16 anos de idade, sofreu uma queda seguida de avulsao do dente 21. Relatou que o dente foi mantido em agua e reimplantado apos 10 minutos, sendo instalada uma contencao flexivel, a qual foi removida apenas quando se iniciou o tratamento endodontico, 9 meses apos o trauma. Ao exame radiografico, observou-se reabsorcao radicular externa a nivel medio e apical, portanto, foi definido o protocolo terapeutico com o uso de medicacao intracanal a base de hidroxido de calcio, associado ao propilenoglicol e oxido de zinco, a qual foi capaz de permanecer intracanal por um periodo superior a dois anos e estabilizar a reabsorcao radicular externa. Conclui-se que o reimplante dentario associado ao protocolo de tratamento utilizando esta medicacao intracanal sem trocas periodicas, possibilitou a manutencao do dente em funcionalidade e estetica, e evitou possiveis sequelas psicologicas. Descritores: Avulsao Dentaria; Reimplante Dentario; Reabsorcao da Raiz; Hidroxido de Calcio; Oxido de Zinco.

Análise, ex vivo, da e cácia e da acurácia de localizadores apicais eletrônicos na determinação do comprimento de trabalho

Introducao: a utilizacao dos localizadores apicais eletronicos (LAEs) e imprescindivel na obtencao do comprimento real de trabalho (CRT), visto que o metodo radiogra co apresenta limitacoes. Objetivo: o objetivo deste estudo foi comparar a e cacia e acuracia de tres LAEs (Root ZX, NovApex e Justy II), na determinacao do CRT. Metodos: trinta incisivos humanos extraidos foram selecionados. Apos a abertura coronaria e preparo cervical, uma lima tipo K #15 foi introduzida no interior do canal ate sua ponta atingir o forame apical; o comprimento real foi observado utilizando-se um paquimetro digital e magnificacao com microscopio operatorio (25x). O CRT de cada dente foi obtido subtraindo-se 1mm do comprimento da lima. Entao, os dentes foram inseridos, ate o nivel cervical, em uma esponja para arranjos orais, posicionada em uma caixa plastica transparente, embebida em solucao salina a 0,9%. Um endodontista experiente e calibrado realizou 30 mensuracoes com cada aparelho, perfazendo um total de 90 medidas. Resultados: por meio da analise de variância (ANOVA), com a qual se verificou a e cacia, demonstrou-se que nao houve diferenca estatisticamente signi cativa (p = 0,4505) entre os aparelhos. Na comparacao entre os tres LAEs quanto ao CRT, nao houve diferenca estatisticamente signi cativa: Root ZX (p = 0,3418); NovApex (p = 0,3031) e Justy II (p = 0,4080). Entretanto na analise de regressao por meio do gra co de dispersao, o NovApex mostrou melhor acuracia do que os outros localizadores apicais eletronicos, com precisao de 93%. Conclusoes: os LAEs utilizados foram eficazes; contudo, apesar de o NovApex ter apresentado maior acuracia, mais estudos devem ser realizados.

Treatment of extensive cystic lesion in the maxilla associated with dens in dente

Dens in dente is a dental development malformation that involves more commonly the upper lateral incisors. Infection of the canal of these teeth can cause the formation of chronic periapical lesions. The present study aimed to describe an integrated approach between the endodontic therapy and surgical intervention in an upper lateral incisor with dens in dente type II. A female patient, 14 years old, looked for dental care complaining of left palatal and paranasal bulging. Clinical, radiological and histopathological findings suggested periradicular cyst. First, marsupialization was performed to reduce the size of the lesion and to favor its enucleation, with less risk of injuring the tooth and vital structures. After diagnosis of pulp necrosis and in attempt to reduce the infection via canal, we used the reciprocating instrumentation associated with irrigation with sodium hypochlorite, intracanal medication based on calcium hydroxide and filled with a thermoplastic filling. After a year of marsupialization, fistulectomy and complete enucleation of the lesion were performed. Proservation was performed 1, 3, 6 and 12 months following marsupialization. Six months after enucleation, we observed the periradicular repair and remission of symptoms. The extensive apical lesion associated with dens in dente type II can be treated with a combination of surgical and endodontic therapy.

Integração multidisciplinar na reabilitação pós traumatismo dentário

Dentes tratados endodonticamente com extensas perdas de estrutura dentaria causadas por traumatismo dentario representam um desafio clinico. Para a reabilitacao destes dentes, se faz necessaria a utilizacao de meios que promovam retencao e longevidade as restauracoes. O uso de pinos de fibra de vidro pre-fabricados associados as restauracoes diretas tem representado uma alternativa eficaz, que vem alcancando prognosticos favoraveis. O objetivo deste trabalho e descrever um caso clinico relacionado a um traumatismo dos incisivos superiores, e mostrar o tratamento integrado proposto. O tratamento a ser realizado nos dentes 11 e 21 consistiu na obturacao do canal radicular, com posterior cimentacao de pinos de fibra de vidro e realizacao de restauracoes adesivas diretas, auxiliadas por meio de enceramento diagnostico e a utilizacao de guia palatina de silicone. Nos dentes 12 e 22 realizou-se o tratamento restaurador com resina composta. Diante este traumatismo complexo envolvendo grande destruicao coronaria, os pinos de fibra de vidro associados as restauracoes diretas possibilitaram a reabilitacao e mostraram-se como indicacoes viaveis, pois devolveram a funcao, estetica, protegeram o remanescente dental e preveniram possiveis recontaminacoes do canal radicular. Descritores: Endodontia; Traumatismos Dentarios; Pinos Dentarios; Resinas Compostas.

Avaliação da suscetibilidade antimicrobiana de bactérias anaeróbias facultativas isoladas de canais radiculares de dentes com insucesso endodôntico frente aos antibióticos de uso sistêmico

IntroductionBacteria associated with failure endodontic treatment are capable of acquiring and expressing resistance against antimicrobial agents usually used to treat infections, which makes necessary, in some cases, laboratory tests in order to detect the resistance or antimicrobial susceptibility of these microorganisms.Objectiveto evaluate the antimicrobial susceptibility of Enterococcus faecalis, Enterococcus faecium, Actinomyces viscosus and Staphylococcus aureus strains isolated from root canals of teeth with failure endodontic treatment.Material and methodEnterococcus faecalis (n=3), Enterococcus faecium (n=3), Actinomyces viscosus (n=3) and Staphylococcus aureus (n=3) clinical strains collected in vivo from root-filled canals with failure endodontic treatment thad been their antimicrobial susceptibility tested by the E-test method in duplicate using the antibiotics: Amoxicillin (AC), Rifampicin (RI), Moxifloxacin (MX), Vancomycin (VA), Tetracycline (TC), Ciprofloxacin (CI), Chloranphenicol (CL), Benzilpenicillin (PG), Amoxicillin + clavulanic acid (XL), Doxycycline (DC), Erythromycin (EM) e Azithromycin (AZ).Resultall the clinical strains tested were susceptible to AC, XL, PG, DC, MX, TC e VA. All the isolated S. aureus strains were susceptible to the 12 tested antibiotics. E. faecalis, E. faecium and A. viscosus strains showed intermediary susceptibility pattern against EM. Some E. faecalis and E. faecium strains were resistant against AZ and RI.Conclusionclinical strains isolated from radicular canals of teeth with failure endodontic treatment showed different antimicrobial susceptibility profiles, and none of E. faecalis or E. faeciumstrains appeared to be susceptible to AZ or EM.