Microbial identification in teeth with pulpar necrosis and periapical abscess and the antimicrobial susceptibility of some anaerobic bacteria

Orientadores: Brenda Paula Figueiredo de Almeida Gomes, Rogerio de Castilho JacintoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Os objetivos do presente estudo foram analisar a microbiota endodôntica em dentes que se apresentavam com necrose pulpar e abscesso periapical; investigar a presença de enterococos, fungos e enterobactérias na saliva e nos canais radiculares; e, determinar in vitro a suscetibilidade antimicrobiana de bactérias anaeróbias estritas isoladas com método de E-test e produção de _-Lactamases. Coletas microbiológicas de 30 canais radiculares e 30 amostras de saliva dos mesmos pacientes foram processadas e identificadas empregando-se métodos de cultura microbiana e testes bioquímicos. Análise estatística foi realizada através dos testes Qui-quadrado de Pearson ou de Fisher. Dos 159 microrganismos isolados nos canais radiculares, predominaram anaeróbios estritos e bactérias Gram-positivas, sendo Peptostreptococcus micros a espécie mais freqüentemente isolada. Fungos, enterobactérias e enterococos foram pouco isolados dos canais radiculares, sendo mais freqüentemente observados em amostras de saliva. Associações de espécies e sinais e sintomas de origem endodôntica foram encontrados. Penicilina G, amoxicilina, amoxicilina + ácido clavulânico, metronidazol foram bastante efetivos frente aos microrganismos testados. Todas as cepas de P. buccae, P. intermedia/nigrescens, P. disiens, P. micros e P. propionicum foram sensíveis à amoxicilina e ao metronidazol. F. nucleatum demonstrou ser bastante resistente aos antibióticos lactâmicos. Observou-se proporção variável de cepas capazes de produzir lactamases. Os resultados sugerem que a infecção endodôntica primária associada a casos sintomáticos é mista, com predomínio de anaeróbios estritos. A presença de fungos, enterococos e enterobactérias não foi significativa tanto nos canais radiculares quanto nas amostras de saliva. Os antibióticos testados mostraram-se efetivos, no entanto resistência microbiana foi detectada em taxas variáveis de acordo com a espécie estudada.Abstract: The aim of the present study was to analyze the endodontic microbiota of teeth with pulp necrosis and spontaneous pain; detect the presence of enterococci, fungi and enteric bacteria in saliva and root canals; and, to determine, in vitro the antimicrobial sensitivity of anaerobic isolates by E-test and _-lactamasis production. Thirty samples were collected from both root canals and saliva, and processed using strict microbiological techniques. Statistical analysis was performed with Persons X2 test or Fisher's Exact Test, as appropriated. A hundred and fifty nine strains were isolated from the root canals, with a predominance of strict anaerobes and gram-positive bacteria, and Peptostreptococcus micros was the most frequently isolated species. Fungi, enterobacteria and enterococci were seldom found in root canals. There were no Enterobacteria in both places. Positive associations between specific species and signs and symptoms of endodontic origin were present. Penicillin G, amoxicillin, amoxicilin + clavulanate, and metronidazole were effective against the tested microorganisms. All strains of P. buccae, P. intermedia/nigrescens, P. disiens, P. micros e P. propionicum were susceptible to amoxicillin and metronidazole. About 12% to 33% of the isolates were able to produce beta-lactamasis. The present results suggested that the primary endodontic infection in symptomatic teeth was mixed, and was predominantly formed by strict anaerobic strains. Fungi, enterococci and enterobacteria were not significantly found in root canals and saliva. The tested antibiotics were effective, however resistance was detected in several clinical isolates.MestradoEndodontiaMestre em Clínica Odontológic

Cost-related variables in the public purchase of dental materials for endodontic application : 10-year analysis

Aim: This study analyzed public procurements for different endodontic materials used in the Brazilian public health system and evaluated the variables related to their cost. Methods: A time-series study was performed by screening materials for endodontic application in the public Brazilian Databank of Healthcare Prices from 2010 to 2019. Data were categorized according to material composition and clinical application. The collated variables were used in a multiple linear regression model to predict the impact of unit price in procurement processes. Results: A total of 5,973 procurement processes (1,524,693 items) were evaluated. Calcium hydroxides were found in 79% of the observations (4,669 processes). Prices drop each year by US$1.87 while MTAs and epoxy resins are increasingly purchased at higher prices (US$50.87; US$67.69, respectively). The microregion, the procurement modality, and the type of institution had no influence on unit prices in the adjusted model (p > 0.05). Conclusions: Calcium hydroxide-based materials were the cheapest and most frequently purchased endodontic materials in the public health care system. Novel formulations are being implemented into clinical practice over time and their cost may be a barrier to the broad application of materials such as MTAs, despite their effectiveness

Avaliação morfométrica de dentes artificiais polirradiculares utilizados para treinamento endodôntico

Introduction: dental practice professionals encounter several urgency cases, mainly related to endodontic problems. To attend to these, professionals need extensive prior preclinical training, being one of the main difficulties the search for models that simulate dental morphology. Aim: to compare the external morphometry of multirooted artificial teeth to literature. Material and method: the artificial teeth (Upper First Premolar, Upper First Molar and Lower First Molar) were donated by the manufacturers: Fábrica de Sorrisos (FS) and IM do Brasil LTDA (IM), totaling 30 teeth. The total length of the tooth and root, height and buccal-palatal and mesial-distal dimensions of the crown were measured with a digital pachymeter. The data were placed in a spreadsheet and the statistical analysis was performed [ANOVA or Kruskal-Wallis and then, Dunnett's test (α=5%)]. Result: the Upper Molar samples of the company Fábrica de Sorrisos presented all variables within the morphometric patterns described in the literature. The other dental groups presented statistically significant differences, maintaining or not a certain proportionality. Conclusion: of all the dental groups analyzed, the upper molar from the company Fábrica de Sorrisos was the only one that presented all the external morphometric aspects according to literature.Introdução: dentro da prática odontológica, os profissionais podem receber diversos casos de urgência, principalmente relacionados a problemas endodônticos e, para atendê-los, há a necessidade de um extenso treinamento pré-clínico prévio, sendo uma das principais dificuldades a busca por modelos que simulem a morfologia dentária. Objetivo: comparar a morfometria de dentes artificiais polirradiculares à literatura. Material e método: os dentes artificiais (Primeiro Pré-molar Superior, Primeiro Molar Superior e Primeiro Molar Inferior) foram doados pelos fabricantes: Fábrica de Sorrisos (FS) e IM do Brasil Ltda. (IM), totalizando 30 dentes. Foi realizada mensuração do comprimento total do dente e o da raiz, da altura e das dimensões vestíbulo-palatina e mésio-distal da coroa, com paquímetro digital. Os dados foram dispostos em uma planilha de cálculo e realizou-se a análise estatística [ANOVA ou Kruskal-Wallis e, após, teste de Dunnett (α=5%)]. Resultado: a amostra de molares superiores da empresa FS apresentou todas as variáveis dentro dos padrões morfométricos descritos na literatura. Os demais grupos dentários apresentaram diferenças estatisticamente significantes, mantendo ou não certa proporcionalidade. Conclusão: de todos os grupos dentários pesquisados o molar superior da empresa FS foi o único que apresentou todos os aspectos morfométricos externos de acordo com os dados da literatura

Novel chlorhexidine-loaded polymeric nanoparticles for root canal treatment

Persistence of microorganisms in dentinal tubules after root canal chemo-mechanical preparation has been well documented. The complex anatomy of the root canal and dentinal buffering ability make delivery of antimicrobial agents difficult. This work explores the use of a novel trilayered nanoparticle (TNP) drug delivery system that encapsulates chlorhexidine digluconate, which is aimed at improving the disinfection of the root canal system. Chlorhexidine digluconate was encapsulated inside polymeric self-assembled TNPs. These were self-assembled through water-in-oil emulsion from poly(ethylene glycol)-b-poly(lactic acid) (PEG-b-PLA), a di-block copolymer, with one hydrophilic segment and another hydrophobic. The resulting TNPs were physicochemically characterized and their antimicrobial effectiveness was evaluated against Enterococcus faecalis using a broth inhibition method. The hydrophilic interior of the TNPs successfully entrapped chlorhexidine digluconate. The resulting TNPs had particle size ranging from 140–295 nm, with adequate encapsulation efficiency, and maintained inhibition of bacteria over 21 days. The delivery of antibacterial irrigants throughout the dentinal matrix by employing the TNP system described in this work may be an effective alternative to improve root canal disinfection

Knowledge of Primary Health Care dentists about endodontic urgencies

Objetivo: avaliar o conhecimento de um grupo de cirurgiões-dentistas que trabalham em Atenção Primária à Saúde acerca de diagnósticos e condutas a serem tomadas diante de urgências em endodontia. Métodos: 24 cirurgiões-dentistas responderam um questionário estruturado, adaptado para o estudo. O instrumento abordava características socioeconômicas e o conhecimento dos cirurgiões-dentistas sobre diagnósticos e condutas perante patologias pulpares e periapicais. Os dados foram submetidos a análises estatísticas descritivas (medidas de variabilidade e de tendência central) e de associação entre os desfechos e as variáveis independentes, pelo Teste t Student e pelo teste de correlação Pearson, todos com α ≤ 0,05. Resultados: a quantidade de acertos dos participantes foi baixa nas perguntas selecionadas, as quais eram vinculadas aos conhecimentos de urgência em endodontia (27,3% – 68,2%). Essa baixa quantidade de acertos foi relacionada às variáveis sexo, idade e tempo de formado. Conclusão: o cirurgião-dentista deve estar preparado para lidar com urgências endodônticas desde a formação acadêmica. Considerando a baixa quantidade de acertos nas questões acerca de urgências endodônticas, atualizações constantes sobre o tema são necessárias, a fim de aprimorar o conhecimento dos profissionais e ampliar a resolutividade dos serviçosObjective: To assess the knowledge of a group of dentists working in Primary Health Care about the diagnostics and behaviors to be adopted to treat endodontic emergencies. Methods: 24 dentists answered a structured questionnaire adapted to the study. The instrument addressed socioeconomic characteristics and the knowledge of dentists about diagnostics and behaviors concerning pulpal and periapical pathologies. The data were subjected to analyses of descriptive statistics (measures of variability and central tendency) and of association between the outcomes and the independent variables using Student’s t-test and Pearson correlation test. Significance was set at α ≤ 0.05. Results: The number of correct answers was low in the questions selected, which were linked to the knowledge of endodontic emergencies (27.3 - 68.2%). The low number of correct answers was related to the variables of sex, age, and time of academic training. Conclusion: Dentists should be prepared to deal with endodontic emergencies since their academic training. The low number of correct answers for questions about endodontic emergencies shows the need for constant updates on the subject, in order to improve the knowledge of the professionals and expand the resoluteness of service

QMix® irrigant reduces lipopolysacharide (LPS) levels in an in vitro model

AbstractThe presence of endotoxin inside the root canal has been associated with periapical inflammation, bone resorption and symptomatic conditions.Objectives To determine, in vitro, the effect of QMix® and other three root canal irrigants in reducing the endotoxin content in root canals.Material and Methods Root canals of single-rooted teeth were prepared. Samples were detoxified with Co-60 irradiation and inoculated with E. coli LPS (24 h, at 37°C). After that period, samples were divided into 4 groups, according to the irrigation solution tested: QMix®, 17% EDTA, 2% chlorhexidine solution (CHX), and 3% sodium hypochlorite (NaOCl). LPS quantification was determined by Limulus Amebocyte Lysate (LAL) assay. The initial counting of endotoxins for all samples, and the determination of LPS levels in non-contaminated teeth and in contaminated teeth exposed only to non-pyrogenic water, were used as controls.Results QMix® reduced LPS levels, with a median value of 1.11 endotoxins units (EU)/mL (

Análisis de expedientes dentales endodónticos de pacientes tratados en una universidad pública del sur de Brasil

Dental record has a fundamental role in dentist performance. This study evaluated the standard registration of dental records of patients submitted to endodontic treatment for undergraduate students (CG) and specialists endodontics students (CE) in a public university in the south of Brazil. The sample was obtained by convenience, consecutively and included dental records patients of a public university in the south of Brazil who were treated at CE and clinical records of patients who were treated at CG, during on the year 2014. Was analyzed the description of endodontic treatment, data retrieved was scored and rated using a modification of the scoring system proposed by Streiner & Norman (1996) and quality of radiographs was performed according to the guidelines of “National Radiological Protection Board”. At dental records were analyzed, 223 belong to CG and 219 belong CE. The records from CE and CG had similar information on the evaluated parameters, except for “presence of rubber dam” and “presence of abbreviature in the description” (Mann-Whitney Test, P = 0.386). The absence of periapical radiographs was higher in CE than CG records (CE = 36.77%; CG = 0.46%). (Mann-Whitney test, P<0.0001). There was a predominance of periapical radiographs with the grades “excellent” and “diagnostically acceptable” in both groups.The quality of records generally obtained good results. The incorporation of new science into the educational program like electronic records and digital imaging techniques, facilitating the constant updating of data related to health and treatment of patients improving the record of the evolution of procedures.O prontuário odontológico tem papel fundamental na atuação do cirurgião-dentista. Este estudo avaliou o padrão de registro de prontuários odontológicos de pacientes submetidos ao tratamento endodôntico por alunos de graduação (GC) e alunos especialistas em endodontia (CE) em uma universidade pública do sul do Brasil. Amostra foi obtida por conveniência, de forma consecutiva e incluiu prontuários odontológicos de pacientes atendidos por CE e prontuários de pacientes atendidos por GC, durante o ano de 2014. Foi analisada a descrição do tratamento endodôntico, os dados recuperados foram pontuados e avaliados usando uma modificação do sistema de pontuação proposto por Streiner & Norman (1996) e a qualidade das radiografias foi analisada de acordo com as diretrizes do “National Radiological Protection Board”. Nos prontuários odontológicos foram analisados, 223 pertencentes ao GC e 219 pertencentes ao CE. Os prontuários do CE e do CG apresentaram informações semelhantes sobre os parâmetros avaliados, exceto para “presença de isolamento absoluto” e “presença de abreviaturas na descrição” (Teste de Mann-Whitney, P = 0,386). A ausência de radiografias periapicais foi maior em CE do que os registros do CG (CE = 36,77%; CG = 0,46%) (Teste de Mann-Whitney, P <0,0001). Houve predomínio de radiografias periapicais com notas “excelente” e “diagnóstico aceitável” em ambos os grupos. A qualidade dos registros obteve bons resultados. Conclui-se que a incorporação de novas ciências ao programa educacional como prontuários eletrônicos e técnicas de imagem digital, facilita a atualização constante dos dados relacionados à saúde e tratamento dos pacientes, melhorando o registro da evolução dos procedimentos.El registro dental juega un papel fundamental en el desempeño del odontólogo. Este estudio evaluó el patrón de registro de registros dentales de pacientes sometidos a tratamiento de endodoncia por estudiantes de pregrado (GC) y estudiantes especialistas en endodoncia (EC) en una universidad pública en el sur de Brasil. La muestra se obtuvo por conveniencia, de forma consecutiva, e incluyó registros dentales de pacientes tratados por CE y registros médicos de pacientes tratados por GC durante 2014. La descripción del tratamiento endodóntico, los datos recuperados fueron puntuados y evaluados utilizando una modificación del sistema de puntuación propuesto por Streiner & Norman (1996) y se analizó la calidad de las radiografías de acuerdo con las directrices de la National Radiological Protection Board. En los registros dentales se analizaron 223 pertenecientes al GC y 219 pertenecientes a la CE. Las historias clínicas de la CE y CG presentaron información similar sobre los parámetros evaluados, excepto por “presencia de aislamiento absoluto” y “presencia de abreviaturas en la descripción” (prueba de Mann-Whitney, p = 0,386). La ausencia de radiografías periapicales fue mayor en los registros de EC que en los de GC (EC = 36,77%; GC = 0,46%) (prueba de Mann-Whitney, P <0,0001). Hubo un predominio de radiografías periapicales con puntajes de “excelente” y “diagnóstico aceptable” en ambos grupos. La calidad de los registros en general tuvo buenos resultados. Se concluye que la incorporación de nuevas ciencias al programa educativo, como la historia clínica electrónica y las técnicas de imagen digital, facilita la actualización constante de los datos relacionados con la salud y el tratamiento de los pacientes, mejorando el registro de la evolución de los procedimientos

Molecular identification of cultivable bacteria from infected root canals associated with acute apical abscess

The objective of this study was to investigate the bacterial composition present in root canals of teeth associated with acute apical abscess by molecular identification (16S rRNA) of cultivable bacteria. Two hundred and twenty strains isolated by culture from 20 root canals were subjected to DNA extraction and amplification of the 16S rRNA gene (PCR), followed by sequencing. The resulting nucleotide sequences were compared to the GenBank database from the National Center of Biotechnology Information through BLAST. Strains not identified by sequencing were submitted to clonal analysis. The association of microbiological findings with clinical features and the association between microbial species were also investigated. Fifty-nine different cultivable bacteria were identified by 16S rRNA gene sequencing, belonging to 6 phyla, with an average number of 6 species per root canal. Molecular approaches allowed identification of 99% of isolates. The most frequently identified bacteria were Prevotella spp., Pseudoramibacter alactolyticus, Parvimonas micra, Dialister invisus, Filifactor alocis, and Peptostreptococcus stomatis. Positive association was found between Prevotella buccae and Pseudoramibacter alactolyticus and between Parvimonas micra and Prevotella nigrescens (both p<0.05). It was concluded that the microbiota of infected root canals associated with acute apical abscess is diverse and heterogeneous, composed mainly of anaerobic Gram-negative bacteria, with the great majority belonging to the phyla Firmicutes and Bacteroidetes273318324CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP302575/2009; 308162/2014-5Sem informação2009/07760-5; 2011/09047-4O objetivo deste estudo foi investigar a composição bacteriana de canais radiculares associados com abscesso apical agudo através de identificação molecular (16S rRNA) de bactérias cultiváveis. Duzentas e vinte cepas, de 20 casos, isoladas por cultura foram submetidas a extração de DNA e amplificação do gene 16S rRNA (PCR), seguido de sequenciamento. As sequências de nucleotídeos obtidas foram comparadas com o banco de dados (GenBank) do National Center of Biotechnology Information através do BLAST. Cepas não identificadas pelo sequenciamento foram submetidas à clonagem. Associação de achados microbiológicos e características clínicas e associação entre espécies bacterianas também foram investigadas. Cinquenta e nove bactérias cultiváveis diferentes foram identificadas pelo sequenciamento do gene 16S rRNA, pertencentes a 6 filos, numa média de 6 espécies por canal. Método molecular permitiu identificação de 99% das cepas isoladas. As bactérias mais frequentes foram Prevotella spp., Pseudoramibacter alactolyticus, Parvimonas micra, Dialister invisus, Filifactor alocis, Peptostreptococcus stomatis. Associação positiva foi encontrada entre Prevotella buccae e Pseudoramibacter alactolyticus, e entre Parvimonas micra e Prevotella nigrescens (p<0,05). Foi concluído que a microbiota de canais radiculares infectados associados com abscesso apical agudo é diversa e heterogênea, composta principalmente por anaeróbios Gram-negativos, pertencentes aos filos Firmicutes e Bacteroidete

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 failure291CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES302575/2009-0sem informaçã