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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Avaliação microbiológica do canal radicular e da reparação apical e periapical após tratamento endodôntico de dentes de cães com vitalidade pulpar e sem vitalidade pulpar com ou sem reação periapical crônica /

Pappen, Fernanda Geraldes. January 2004 (has links)
Orientador: Mário Tanomaru Filho / Banca: Mario Roberto Leonardo / Banca: Ana Paula Vieira Colombo / Resumo: O objetivo deste estudo foi a avaliação da microbiota dos canais radiculares de dentes de cães sem vitalidade pulpar, com e sem reação periapical crônica por meio dos métodos de cultura microbiológica e hibridação DNA-DNA checkerboard, além da análise da reparação dos tecidos apicais e periapicais após o tratamento endodôntico de dentes sem vitalidade pulpar sem ou com lesão periapical e dentes com vitalidade pulpar. Foram utilizados 60 pré-molares de 3 cães. No grupo I foram realizados os casos de biopulpectomia; no grupo II, após a abertura coronária, os canais radiculares permaneceram expostos por 30 dias, visando a contaminação dos mesmos (necropulpectomia I); e no grupo III, os canais radiculares permaneceram expostos ao meio bucal por 7 dias, sendo a seguir, selados por 60 dias, quando as lesões periapicais foram evidenciadas radiograficamente (necropulpectomia II). Anteriormente ao preparo biomecânico foi realizada a colheita de material dos canais radiculares para análise microbiológica dos dentes sem vitalidade pulpar. O tratamento endodôntico foi realizado em todos os grupos, em uma única sessão, e após 180 dias os cães foram mortos e as peças preparadas para análise histopatológica. Os resultados da análise microbiológica por meio da técnica de cultura demonstraram o predomínio de anaeróbios estritos e aeróbios em relação aos microrganismos facultativos. A técnica de checkerboard demonstrou o predomínio de anaeróbios estritos nas duas situações avaliadas. Nos dois métodos de análise microbiológica foi possível observar maior número de células bacterianas no Grupo II, onde os canais radiculares permaneceram expostos ao meio bucal por 30 dias. Os resultados histopatológicos demonstraram presença de infiltrado inflamatório severo, reabsorção apical e óssea nos grupos II e III, com aspectos semelhantes para... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The aim of this study was to evaluate the microbiota of root canals from dog's teeth, with no pulp vitality, with or without radiographic chronic periapical lesion, using a culture microbiologic method and checkerboard DNA-DNA hybridization technique. The repair of apical and periapical tissues was evaluated after the endodontic treatment of root canals, with no pulp vitality, with or without chronic periapical lesion and with vital pulp. It were used dog's premolars from 3 animals, divided into three groups: group I, treatment of teeth with vital pulps; group II, after coronal opening the root canals were exposed to oral environment during 30 days (teeth with no pulp vitality without chronic periapical lesion); and in group III, the root canals were exposed to oral environment during 7 days, and after this, sealed during 60 days, until the radiographic observation of the presence of periapical lesion. Before the biomechanical preparation, the microbiologic samples were obtained from groups II and III. Endodontic therapy was conducted in three groups, in one-visit treatment, and after 180 days, the dogs were killed and the obtained histological sections were stained with hematoxylin-eosin for optical microscopic analysis of the apical and periapical repairing. The results of microbiologic evaluation using culture technique, showed the predominance of obligate anaerobic and aerobic bacteria in both groups, when compared to facultative species. The method checkerboard demonstrated the predominant occurrence of obligate anaerobes in the both clinical situations that were evaluated. For the two microbiological methods used it was possible to observe a greater number of cells in group II, where the root canals were kept exposed to oral environment during 30 days. The histhological results showed inflammatory... (Complete abstract, click electronic address below). / Mestre
62

Presença de genes de resistência a agentes antimicrobianos em saliva, biofilme supragengival e canais radiculares infectados / Presence of antimicrobial resistance genes in saliva, supragingival biofilm and infected root canals

Moraes, Ludmila Coutinho January 2013 (has links)
Embora diferentes estudos indiquem que há um aumento da resistência dos microrganismos aos agentes antimicrobianos prescritos, pouco se sabe a respeito da sua distribuição na cavidade oral. A presente dissertação está dividida em dois capítulos, representados por dois diferentes manuscritos. No manuscrito I, uma revisão sistemática foi realizada e teve como objetivo determinar quais genes de resistência a antimicrobianos foram pesquisados em saliva (S), no biofilme supragengival (SB) e canal radicular (RC). Os termos foram usados em várias combinações nas seguintes bases de dados eletrônicas (MEDLINE, EMBASE, ISI, SCOPUS e OPENGREY). Após seleção dos títulos e análise dos resumos, o texto integral de cada estudo foi obtido. Foram estabelecidos critérios de inclusão e exclusão. Dados epidemiológicos, características metodológicas e os resultados foram obtidos a partir dos estudos. Devido à falta de padronização da metodologia entre os trabalhos, não foi possível realizar uma meta-análise. Realizou-se análise descritiva dos dados. Um total de 151 títulos foram identificados para análise preliminar. Quarenta e nove resumos foram selecionados e 22 textos completos foram obtidos. Sete artigos contemplavam aos critérios de inclusão (S = 2; SB = 0 , e RC = 5). Vinte e seis diferentes genes-alvo foram avaliados. Os genes de resistência mais frequentemente descritos foram os relacionados às tetraciclinas e lactâmicos (5/7). Observa-se que poucos artigos foram selecionados pela estratégia de busca adotada para esta revisão sistemática. Este fato demonstra a falta de padronização nas metodologias dos estudos que utilizam técnicas moleculares para a detecção de genes de resistência bacteriana, tanto em condições de saúde ou doença. No manuscrito II, um estudo de observação clínica e laboratorial foi desenvolvido para detectar a presença de espécies-alvo de Prevotella e o gene cfxA/cfxA2 em amostras de saliva (S), biofilme supragengival (SB) e canais radiculares infectados (RC). Amostras pareadas de S, SB e RC foram coletadas de 42 indivíduos. Os pacientes foram divididos em três grupos: Grupo I - sem infecção aguda/crônica primária do canal radicular (n = 15), Grupo II - presença de infecção aguda primária no canal radicular (n = 12 ) e Grupo III - presença de infecção crônica no canal radicular (n = 15). Foram coletadas amostras de RC apenas para os Grupos II e III. Após o isolamento do DNA, a presença de Prevotella intermedia, Prevotella nigrescens, Prevotella tannerae e do gene cfxA/cfxA2 foi detectada através de PCR. Comparou-se a frequência das espécies e do gene de resistência, considerando diferentes ambientes e condições clínicas. A análise estatística foi realizada. Todas as amostras de S, SB e RC foram positivos para a detecção de DNA bacteriano. As taxas de detecção para espécies de Prevotella foram: S= 53,97%; SB=47,62%, e RC=34,56%. O gene cfxA não foi detectado simultaneamente em três ambientes do mesmo paciente. A presença ou ausência de sintomas espontâneos não influenciou as taxas de detecção para as espécies-alvo e para o gene cfxA/A2 em amostras de RC (teste exato de Fisher , P> 0,05). Espécies de Prevotella e o gene cfxA/cfxA2 foram frequentemente detectados na saliva, placa dental e amostras de canais radiculares. / Although different studies indicate that there is an increased resistance of microorganisms to antimicrobial agents prescribed in Endodontics, little is known about their distribution in the oral cavity. The present dissertation was divided into two chapters, represented by two different manuscripts. In manuscript I, a systematic review was conducted and aimed to determine which antimicrobial resistance genes were investigated in saliva (S), the supragingival biofilm (SB) and root canal (RC). The terms were used in various combinations in the following electronic databases (MEDLINE, EMBASE, ISI, SCOPUS and OPENGREY). After title screening and abstract analysis, the full text of each study was obtained. The relevance of each study to the question of interest was determined through inclusion and exclusion criteria. Epidemiologic data, methodological characteristics and results were collected from the studies. Due to lack of methodology standardization among the papers, it was not possible to perform a meta-analysis. Descriptive data analysis was performed. A total of 151 titles were identified for preliminary analysis. Forty-nine abstracts were selected, and full texts of 22 studies were obtained. Seven articles matched the inclusion criteria (S=2; SB= 0; and, RC=5). Twenty-six different targeted genes have been evaluated. The most frequently investigated groups of resistance genes were related to tetracycline and lactamics (5/7). Few articles in the literature fit in the search strategy adopted by this systematic review, demonstrating the lack of standardization in the methodologies of studies using molecular techniques for the detection of bacterial resistance genes to antibiotics in oral cavity, either in health or disease conditions. In the manuscript II, an observational clinical and laboratorial study was developed to identify the presence of targeted Prevotella species and the cfxA/cfxA2 gene in samples from saliva (S), supragingival biofilm (SB) and infected root canals (RC). Paired samples of S, SB and RC were collected from 42 subjects. Patients were divided into three groups: Group I - no acute or chronic root canal infection (n = 15); Group II - presence of acute root canal infection (n = 12), and Group III - presence of chronic root canal infection (n=15). RC samples were collected for Groups II and III. After DNA isolation, the presence of Prevotella intermedia, Prevotella nigrescens, Prevotella tannerae and the cfxA/cfxA2 gene was detected through gene-specific PCR. The frequency of the species and of the resistance was compared, considering different environments and clinical conditions. Statistical analysis was carried out. All samples from S, SB and RC were positive for the presence of bacteria. The overall detection rates for Prevotella species were: S = 53.97%; SB = 47.62%; and, RC = 34.56%. The cfxA gene was not detected simultaneously in the three environments from the same patient. The presence of absence of spontaneous symptoms had not influenced the detection rates for the targeted species and for the cfxA/A2 gene in RC samples (Fisher Exact Test, P>.05). Prevotella species and the gene cfxA/cfxA2 were frequently detected in saliva, dental plaque and root canal samples.
63

Desvio apical : comparação in vitro de três técnicas de preparo dos canais radiculares

López, Fernanda Ullmann January 2007 (has links)
O desvio apical é um fator bastante relevante na terapia endodôntica pela possibilidade de conduzir o tratamento proposto ao insucesso. Este estudo se propôs a realizar uma avaliação in vitro da ocorrência de desvio apical e sua magnitude nas instrumentações manual com limas de aço-inoxidável, rotatória de giro contínuo com o sistema K3 e rotatória de giro alternado com contra-ângulo NSK e limas de aço-inoxidável, em raízes mésio-vestibulares de molares superiores. A amostra foi formada por 60 raízes que, após a inclusão numa modificação da mufla de Bramante, foram seccionadas longitudinalmente. De acordo com o ângulo e raio da curvatura do seu canal, as raízes foram paritariamente divididas em três grupos. Uma das metades de cada raiz teve sua face interna digitalizada por scanner de mesa. As raízes foram remontadas nas muflas e seus canais instrumentados. A mesma metade de cada raiz teve sua face interna novamente digitalizada em três momentos distintos: primeiro, na confecção do preparo apical com a lima 30, após com a lima 35 e, por fim, com a lima 40. Cada imagem pós operatória (limas 30, 35 e 40) foi sobreposta à imagem pré-opertória no programa Adobe Photoshop. Após, foram transferidas ao programa AutoCad, onde o desvio apical foi mensurado. Para a comparação entre as limas dos três grupos foram utilizados os testes nãoparamétricos de Friedman e Wilcoxon que encontraram diferença significativa. (p=0,000) Para a comparação entre os três grupos foi utilizado o teste não-paramétrico Kruskal-Wallis (p=0,000) que demonstrou haver diferença significativa entre os grupos estudados. / Apical transportation has considerable relevance in endodontic therapy, as it may lead to treatment failure. This study conducted an in vitro comparative analysis of apical transportation produced in mesiobuccal roots of upper molars by (i) manual instrumentation using stainless steel files, (ii) K3 rotary Ni-Ti system, and (iii) a reciprocating NSK handpiece, also with stainless steel files. The sample comprised 60 roots that were inserted in a Bramante muffle and then longitudinally sectioned. Roots were subdivided pair-wise into three groups according to canal angle and radius. The inner surface of one root half was digitized using a scanner. Roots were then reassembled onto the muffles and had their canals instrumented. The same root half had its inner surface digitized again after instrumentation with three different file sizes: 30, 35 and 40. Each image obtained therefrom was superimposed over the pre-operative image using the Adobe Photoshop software. After, images were transferred to the AutoCad software for apical transportation measurements. The non-parametric Friedman and Wilcoxon tests were adopted to compare results for the three different file sizes, and showed the statistically significant differences between the results obtained (p=0,000). Similarly, the comparison between the three treatment groups by the nonparametric Kruskal-Wallis test revealed statistically significant differences.
64

Presença de genes de resistência a agentes antimicrobianos em saliva, biofilme supragengival e canais radiculares infectados / Presence of antimicrobial resistance genes in saliva, supragingival biofilm and infected root canals

Moraes, Ludmila Coutinho January 2013 (has links)
Embora diferentes estudos indiquem que há um aumento da resistência dos microrganismos aos agentes antimicrobianos prescritos, pouco se sabe a respeito da sua distribuição na cavidade oral. A presente dissertação está dividida em dois capítulos, representados por dois diferentes manuscritos. No manuscrito I, uma revisão sistemática foi realizada e teve como objetivo determinar quais genes de resistência a antimicrobianos foram pesquisados em saliva (S), no biofilme supragengival (SB) e canal radicular (RC). Os termos foram usados em várias combinações nas seguintes bases de dados eletrônicas (MEDLINE, EMBASE, ISI, SCOPUS e OPENGREY). Após seleção dos títulos e análise dos resumos, o texto integral de cada estudo foi obtido. Foram estabelecidos critérios de inclusão e exclusão. Dados epidemiológicos, características metodológicas e os resultados foram obtidos a partir dos estudos. Devido à falta de padronização da metodologia entre os trabalhos, não foi possível realizar uma meta-análise. Realizou-se análise descritiva dos dados. Um total de 151 títulos foram identificados para análise preliminar. Quarenta e nove resumos foram selecionados e 22 textos completos foram obtidos. Sete artigos contemplavam aos critérios de inclusão (S = 2; SB = 0 , e RC = 5). Vinte e seis diferentes genes-alvo foram avaliados. Os genes de resistência mais frequentemente descritos foram os relacionados às tetraciclinas e lactâmicos (5/7). Observa-se que poucos artigos foram selecionados pela estratégia de busca adotada para esta revisão sistemática. Este fato demonstra a falta de padronização nas metodologias dos estudos que utilizam técnicas moleculares para a detecção de genes de resistência bacteriana, tanto em condições de saúde ou doença. No manuscrito II, um estudo de observação clínica e laboratorial foi desenvolvido para detectar a presença de espécies-alvo de Prevotella e o gene cfxA/cfxA2 em amostras de saliva (S), biofilme supragengival (SB) e canais radiculares infectados (RC). Amostras pareadas de S, SB e RC foram coletadas de 42 indivíduos. Os pacientes foram divididos em três grupos: Grupo I - sem infecção aguda/crônica primária do canal radicular (n = 15), Grupo II - presença de infecção aguda primária no canal radicular (n = 12 ) e Grupo III - presença de infecção crônica no canal radicular (n = 15). Foram coletadas amostras de RC apenas para os Grupos II e III. Após o isolamento do DNA, a presença de Prevotella intermedia, Prevotella nigrescens, Prevotella tannerae e do gene cfxA/cfxA2 foi detectada através de PCR. Comparou-se a frequência das espécies e do gene de resistência, considerando diferentes ambientes e condições clínicas. A análise estatística foi realizada. Todas as amostras de S, SB e RC foram positivos para a detecção de DNA bacteriano. As taxas de detecção para espécies de Prevotella foram: S= 53,97%; SB=47,62%, e RC=34,56%. O gene cfxA não foi detectado simultaneamente em três ambientes do mesmo paciente. A presença ou ausência de sintomas espontâneos não influenciou as taxas de detecção para as espécies-alvo e para o gene cfxA/A2 em amostras de RC (teste exato de Fisher , P> 0,05). Espécies de Prevotella e o gene cfxA/cfxA2 foram frequentemente detectados na saliva, placa dental e amostras de canais radiculares. / Although different studies indicate that there is an increased resistance of microorganisms to antimicrobial agents prescribed in Endodontics, little is known about their distribution in the oral cavity. The present dissertation was divided into two chapters, represented by two different manuscripts. In manuscript I, a systematic review was conducted and aimed to determine which antimicrobial resistance genes were investigated in saliva (S), the supragingival biofilm (SB) and root canal (RC). The terms were used in various combinations in the following electronic databases (MEDLINE, EMBASE, ISI, SCOPUS and OPENGREY). After title screening and abstract analysis, the full text of each study was obtained. The relevance of each study to the question of interest was determined through inclusion and exclusion criteria. Epidemiologic data, methodological characteristics and results were collected from the studies. Due to lack of methodology standardization among the papers, it was not possible to perform a meta-analysis. Descriptive data analysis was performed. A total of 151 titles were identified for preliminary analysis. Forty-nine abstracts were selected, and full texts of 22 studies were obtained. Seven articles matched the inclusion criteria (S=2; SB= 0; and, RC=5). Twenty-six different targeted genes have been evaluated. The most frequently investigated groups of resistance genes were related to tetracycline and lactamics (5/7). Few articles in the literature fit in the search strategy adopted by this systematic review, demonstrating the lack of standardization in the methodologies of studies using molecular techniques for the detection of bacterial resistance genes to antibiotics in oral cavity, either in health or disease conditions. In the manuscript II, an observational clinical and laboratorial study was developed to identify the presence of targeted Prevotella species and the cfxA/cfxA2 gene in samples from saliva (S), supragingival biofilm (SB) and infected root canals (RC). Paired samples of S, SB and RC were collected from 42 subjects. Patients were divided into three groups: Group I - no acute or chronic root canal infection (n = 15); Group II - presence of acute root canal infection (n = 12), and Group III - presence of chronic root canal infection (n=15). RC samples were collected for Groups II and III. After DNA isolation, the presence of Prevotella intermedia, Prevotella nigrescens, Prevotella tannerae and the cfxA/cfxA2 gene was detected through gene-specific PCR. The frequency of the species and of the resistance was compared, considering different environments and clinical conditions. Statistical analysis was carried out. All samples from S, SB and RC were positive for the presence of bacteria. The overall detection rates for Prevotella species were: S = 53.97%; SB = 47.62%; and, RC = 34.56%. The cfxA gene was not detected simultaneously in the three environments from the same patient. The presence of absence of spontaneous symptoms had not influenced the detection rates for the targeted species and for the cfxA/A2 gene in RC samples (Fisher Exact Test, P>.05). Prevotella species and the gene cfxA/cfxA2 were frequently detected in saliva, dental plaque and root canal samples.
65

Estudo in vitro da anatomia dos canais radiculares de molares permanentes de humanos / In vitro study of the anatomy of the root canals of permanent human molar teeth

Lima, Fernando Jose Camello de 19 July 2005 (has links)
Orientador: Brenda P. F. A. Gomes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-04T21:56:23Z (GMT). No. of bitstreams: 1 Lima_FernandoJoseCamellode_M.pdf: 4661786 bytes, checksum: 585044641889708ea8ca89cc73fd7064 (MD5) Previous issue date: 2005 / Resumo: O presente estudo teve como objetivo investigar a moriologia dos canais radiculares dos molares permanentes de humanos, identificando a configuração dos canais radiculares (classificação de WEINE modificada), os istmos, canais em C, e a correlação entre anatomia externa e interna. Foram utilizados 131 dentes: primeiros e segundos molares superiores (1°Se 2°SMS) e primeiros e segundos molares inferiores (1°Se 2°8 MI), obtidos em Maceió, AL. Os dentes tiveram as suas características externas registradas, para aí serem seccionados na junção amelo-cementária (JAC), para a visualização dos soalhos e das entradas dos canais radiculares. As raízes foram seccionadas transversalmente a 1; 2,5; 4; 5,5 e 7 mm do ápice e examinadas pelo lado apical no estereomicroscópio. Os dados obtidos foram submetidos ao teste do qui-quadrado com significância de 5%. Encontraram-se todos os tipos estudados de canais radiculares nas raízes mésiovestibulares (MV) dos MS. As raízes palatinas (P) dos 1°SMS e distais (O) de 2°S MI só tiveram um canal, enquanto que esta configuração não foi encontrada nas raízes mesiais (M) de 1°SMI. Os istmos estiveram presentes nas raízes MV dos MS em 98,5%, disto-vestibulares (OV) de MS em 10,4% e nos MI, em 91,1% das raizes mesiais (M) e 46,4% das raizes (O). Seis dentes tiveram canais em C, desses, só um não apresentava fusionamento radicular. O soalho da câmara pulpar nos 1°SMS foi trapezoidal em 75% dos casos e triangular no 2° MS em 53,6% dos casos. Os MS com projeções de cúspides MV apresentaram 81,3% de casos nos 1°SMS e 60,7% nos 2°SMS com mais de um canal na raiz MV. Pode-se concluir que as raizes MV de MS e M de MI têm maior probabilidade de possuírem dois canais. Quanto aos istmos, exceto as raízes P e eventuais raízes V dos MS, todas as outras raízes apresentaram istmos nos canais radiculares, porém a maior incidência apareceu nas raizes MV dos 1°SMS, e nas raízes M dos MI. Quanto ao canal em C, todos os molares, exceto os 1°SMI, mostraram esta configuração anatômica ao nível de raiz, sendo isto mais encontrado nas raízes fusionadas. Os MS, principalmente os primeiros molares, com projeções de cúspides MV apresentam maior possibilidade de ter mais de um canal na raiz MV / Abstract: The aim of this study was to investigate the root canais morphology of permanent human molars, to identify the root canal configuration (Weine modified), to verify the presence of isthmus and C-shapes configuration in root canais, and to establish a correlation between internal/external anatomies. One hundred and thirty-one first and second upperllower molars obtained from Maceio, AL, Brazil, were used. Teeth were sectioned in the enamel- cement junction to investigate pulp canal chamber floar and orifice shapes. Then, the roots were transversally sectioned at 1; 2,5; 4; 5,5 and 7 mm from the apex. Afterwards, they were investigated in stereomicroscopy from an apex side view. Data obtained were submitted to chi-square test. The major diversity of root canal types was found in mesial-buccalroots of the uppermolars. Palatal roots of 1st upper molar and distal roots of 2nd lower molars presented only one root canal, while it did not happen in mesial roots of 1st lower molars. Isthmus were presentin mesial-buccalrootsof the upper molars (98,5%), distal-buccal roots of the upper molars (10,4%), mesial root of the lower molars (91,1%) and distal root of the lower molars (46,4%) of the cases. C-shape root canais were found in 6 teeth, in which, only one did not show root-fusion. Most chamber floar shapes were trapezoidal in 1st (75%) and triangle in the 2nd upper molars (53,6%). First upper molars presented in 81,3% a projection of the mesial-buccal cusps, and 60,7% of the 2nd upper molars showed greater possibility of presenting more than one canal in the mesial-buccal root. In conclusion, mesial-buccal roots in upper molars and mesial roots in lower molars presented more often two root canais. Isthmus was found in ali root canais, except from palatine and eventually buccal roots of upper molars. C-shape root canal morphology were found in ali molars besides first lower ones; being frequently found in teeth with fusioned roots. First upper molars with an overprojected mesial buccal cusp showed more frequently two root canais / Mestrado / Endodontia / Mestre em Clínica Odontológica
66

Influencia do sistema adesivo na microdureza do cimento resinoso dual na cimentação de pinos pre-fabricados de fibra de vidro em diferentes profundidades / Influence of adhesive system on hardening of dual-cured resin cement at different depths in restorations with fiber posts

Ozaki, Jansen 02 September 2006 (has links)
Orientador: Luis Alexandre Maffei Sartini Paulillo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-05T23:18:11Z (GMT). No. of bitstreams: 1 Ozaki_Jansen_M.pdf: 4599360 bytes, checksum: ecab3b09dc88aad3d46bc54a8a659ccb (MD5) Previous issue date: 2006 / Resumo: Este trabalho teve como objetivo avaliar a dureza Knoop (KHN) de cimentos resinosos duais na cimentação de pinos de fibra de vidro com diferentes sistemas adesivos e profundidades do canal radicular. Para este estudo foram utilizados 48 incisivos bovinos que tiveram suas coroas seccionadas e as raízes tratadas endodonticamente. Para a restauração utilizando pino de fibra de vidro e os sistemas de cimentação as raízes foram aleatoriamente dividas em 6 grupos: Grupo 1: Single Bond (3M ESPE)/RelyX ARC (3M ESPE), grupo 2: ED Primer (Kuraray)/Panavia F (Kuraray), grupo 3: Single Bond (3M ESPE)/Panavia F (Kuraray), grupo 4: ED Primer (Kuraray)/RelyX ARC (3M ESPE), grupo 5: sem adesivo/RelyX ARC (3M ESPE) e grupo 6: sem adesivo/Panavia F (Kuraray). As raízes restauradas foram armazenadas por 48 horas sob abrigo da luz e seccionados longitudinalmente para se avaliar a KHN nas profundidades cervical, média e apical. Para a microscopia eletrônica de varredura (MEV) foram selecionadas e preparadas 4 hemi-raízes para se observar à qualidade da formação de tags de resina no interior dos túbulos. Os maiores valores de dureza foram encontrados no grupo 6 que não utilizou nenhum tipo de sistema adesivo, e não apresentou nenhuma diferença estatística significativa entre a profundidade média e apical. O grupo 4 apresentou os menores valores de KHN comparado aos demais grupos. O sistema adesivo frasco único para a técnica do condicionamento ácido total apresentou uma camada de lama dentinária na região do terço apical, nas demais regiões demonstrou formação homogênea de tags de resina. O cimento Panavia F apresentou a maior dureza KHN em relação ao Rely X ARC em todas as profundidades testadas e o sistema adesivo influenciou a microdureza KHN dos cimentos resinosos na cimentação de pinos pré-fabricados nas regiões mais profundas do canal radicular / Abstract: The purpose of this study was to evaluate the Knoop hardness (KHN) of dual cure resin cements used to bond fiber posts at different regions of root canal dentin. Forty eight extracted roots of bovine teeth were used. After root canal treatment they were randomly divided into six groups of 8 roots each. Fiber posts were inserted with two different adhesive systems and dual cure luting resin cements. Group 1: Single Bond (3M ESPE)/RelyX ARC/(3M ESPE), group 2: ED Primer (Kuraray)/Panavia F (Kuraray), group 3: Single Bond (3M ESPE)/Panavia F (Kuraray), group 4: ED Primer (Kuraray) RelyX ARC/(3M ESPE), group 5: no adhesive system/RelyX ARC/(3M ESPE) and group 6: no adhesive system/Panavia F (Kuraray). The fixed and bonded specimens were stored for 48 hours, sectioned longitudinally and Knoop hardness measured at coronal, medium and apical regions. Four root halves of each group was then processed for evaluation by SEM of resin tags formation in dentin. The highest KHN were obtained with group 6 that it didn't use adhesive system none, not presenting any significant difference among the medium and apical depth. The group 4 had the lowest KHN compared to the other groups. Conditioning of the root canal dentine with phosphoric acid and use one-bottle bonding systems gave a more uniform penetration of resin tags than observed after the use of ¿self-etching¿ adhesives. Dual cure resin cements used with different adhesive systems and the depth, influenced in the Knoop hardness, which was significantly reduced in the apical region. Panavia F resin cement showed the highest KHN means in all of the tested depths / Mestrado / Dentística / Mestre em Clínica Odontológica
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Analise microbiologica, quantificação de endotoxinas de dentes com infecções endodonticas primarias e suscetibilidade antimicrobiana / Microbiologic investigation, quantification of endotoxin and antimicrobial susceptibility in primary endodontic infection and the salivary carriage of selected endodontic pathogens

Martinho, Frederico Canato, 1981- 30 November 2007 (has links)
Orientador: Brenda Paula Figueiredo de Almeida Gomes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-09T16:41:43Z (GMT). No. of bitstreams: 1 Martinho_FredericoCanato_M.pdf: 2565020 bytes, checksum: d3b12dfab50de25f375d07ea0056245c (MD5) Previous issue date: 2007 / Resumo: O conhecimento das espécies microbianas assim como da suscetibilidade das mesmas à terapia endodôntica é importante para o sucesso do tratamento. Sendo assim, a proposta do presente estudo foi: 1) Analisar a microbiota endodôntica de dentes com necrose pulpar e presença de lesão periapical (C1) e correlacionar com os sinais e sintomas clínicos; 2) investigar mudanças microbiológicas após o preparo químico-mecânico (PQM) (C2); 3) investigar a presença de Entreococcus spp., Candida spp. e enterobactérias na saliva dos pacientes submetidos a terapia endodôntica; 4) quantificar endotoxinas antes (C1) e após PQM (C2); 5) determinar in vitro a suscetibilidade antimicrobiana de algunsmicrorganismos isolados das infecções endodônticas primárias. Amostras microbiológicas foram coletadas da saliva e do canal radicular de 30 pacientes. Foram identificados 182 microrganismos nos canais radiculares, sendo 65,38% anaeróbios estritos. As espécies mais freqüentemente encontradas foram P. micros (63,3%), P. intermedia (50%), S. mitis (30%). Associações positivas foram encontradas entre dor à percussão e E. lentum; dor à palpação e G.haemolysans e E. lentum; fístula e P. micros; exsudato purulento e Bifidobacterium spp. As espécies Peptostreptococcus spp., Fusobacterium spp., Porphyromonas spp., Prevotella spp. foram analisadas e mostraram-se suscetíveis a ação da amoxicilina e da mesma associada ao ácido clavulânico. Maiores concentrações de endotoxinas foram quantificadas nos dentes com sintomatologia clínica. Associação positiva entre LPS e a presença de dor à percussão foi encontrada (p<0,01) Conclusão: A infecção endodôntica primária caracterizou-se ser do tipo mista e polimicrobiana, com predomínio de microrganismos anaeróbios estritos, principalmente bacilos Gramnegativos; a presença de sinais e/ou sintomas clínicos mostrou estar relacionada com determinadas espécies tais como Eubacterium lentum, Gemella haemolysans, Peptostreptococcus micros e Bifidobacterium spp. comumente isoladas em infecções endodônticas primárias; Candida spp. e Enterococcus spp. foram mais freqüentemente isolados da saliva do que as Enterobacteria spp. O isolamento das espécies C. albicans e E. faecalis no canal radicular foram associados com a identificação das espécies na saliva; o PQM dos canais radiculares foi eficaz na redução do número de microrganismos. Mudança na microbiota foi encontrada após PQM. Amoxicilina associada ao ácido clavulânico mostrou ser uma potente combinação contra microrganismos envolvidos na infecção de origem endodôntica. Altas concentrações de endotoxinas nos canais radiculares parecem estar relacionadas com a presença de sintomatologia clínica, particularmente com a dor à percussão. O PQM foi capaz de reduzir a concentração inicial de endotoxinas em todos os canais radiculares, entretanto não foi capaz de eliminá-las / Abstract: Bacteria and their by-products play an important role in the etiology and development of pulp and periapical diseases. The knowledge of endodontic microbiota and its susceptibility to endodontic therapy is important to a successful treatment. Therefore the aims of this study were: 1) to analyse the root canal microbiota in infected teeth with pulp necrosis and periapical lesions (C1) and its correlation with the clinical signs and symptoms; 2) to investigate the variations in the susceptibilities of endodontic microflora to biomechanical procedures (C2); 3) to investigate Candida spp., Enterococcus spp. and enterobacteria in saliva from the patients under endodontic therapy; 4) to quantify endotoxins before (C1) and after chemo-mechanical preparation (CMP) (C2); 5) to determine in vitro the antimicrobial susceptibility rates of the microrganisms recovered from the root canals with primary endodontic infections. Thirty root canals were microbiologically sampled before (C1) and after CMP (C2). At the baseline samples (C1), a total of 182 microrganisms were identified. Strict anaerobic or microphilic species predominated in 65.38%. P. micros (63.3%), P. intermedia (50%), S. mitis (30%) were the most frequent species recovered from the root canals at the baseline samples (C1). Associations between terderness to percussion and the presence of E. lentum; pain on palpation and G. haemolysans and E. lentum; sinus tract and P. micros; Purulent exudate and Bifidobacterium spp. (p<0.05) were found. Peptostreptococcus spp., Fusobacterium spp., Porphyromonas spp., Prevotella spp. were susceptible to amoxicilin and amoxicillin + clavulanate. Higher levels of endodotoxin were detected in teeth with clinical symtphomatology. A positive association was found between the presence of LPS and tenderness to percussion (p<0.01).It was concluded that microbiota from infected root canals with pulp necrosis and periapical lesions was comprised by a mixed and polimicrobial flora, dominated by strict anaerobes, particulary Gram-negative rods. Signs and symptoms seemed to be related to the presence of specific bacteria species Eubacterium lentum, Gemella haemolysans, Peptostreptococcus micros e Bifidobacterium spp.. Candida spp. and Enterococcus were more requently recovered from saliva than Enterobacteria spp. Isolation of C. albicans and E. faecalis from root canals were associated with their identification in the saliva samples. CMP was efficient in reducing the number of microorganisms. Changing in root canal flora was detected after endodontic procedures. Amoxicilin associated with clavulanate was an effective and a strong antimicrobial agent against microorganisms involved in endodontic infections. High contents of LPS seem to be related to the presence of clinical symptomatology, particulary tenderness to percussion. CMP was effective in reducing the initial amount of endotoxin in all root canal samplings but was not able to eliminate it / Mestrado / Endodontia / Mestre em Clínica Odontológica
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Use of Electromagnetic Stimulation in Combination with Low Concentration Sodium Hypochlorite on an In Vitro Enterococcus Faecalis Biofilm on Root Canal Treated Teeth

Brothers, Kara M. January 2021 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: A novel device developed by J. Morita can generate electromagnetic stimulation (EMS) into the root canal. Objectives: The purpose of this study was to determine the anti-biofilm effect of EMS combined with low concentrations of NaOCl against an established biofilm of Enterococcus faecalis in an in vitro human tooth model. Materials and Methods: Single rooted human teeth were standardized and an E. faecalis biofilm was established in the canal. The specimens were subject to six treatment groups: 1) 1.5% NaOCl; 2) 1.5% NaOCl and EMS; 3) 0.25% NaOCl; 4) 0.25% NaOCl and EMS; 5) saline and 6) saline and EMS. Biofilm was collected, plated, and the number of colony forming units (CFU)/mL was used to determine antibacterial activity. Results: The effect of treatment group on bacterial counts were made using one-way ANOVA followed by pair-wise comparisons. Although there was no significant difference between individual groups tested, there was statistically significant difference between the average difference between ‘treatments with EMS’ and ‘treatments without EMS.’ Conclusion: EMS can improve the antibacterial efficacy of NaOCl against an established biofilm of E. faecalis in an in vitro human tooth model
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Comparison of guided endodontic access with and without pin fixation in 3D printed teeth with simulated pulp canal obliteration

Long, Jacob Daniel 06 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: In order to successfully treat an infected root canal system (RCS), it is required to locate all root canals and have an access path to the apex of each canal. This can be challenging in teeth with pulp canal obliteration (PCO), often leading to increased chair time and increased risk of iatrogenic errors. Guided endodontic access (GEA) combines information from a cone-beam computed tomography (CBCT) scan with an intra-oral scan to create a stent. GEA stents with or without fixation pins have been shown to be successful in accurately negotiating a RCS with PCO. Objective: Compare the degree of deviation and difference in 3D offset at the base to apical tip of the drill from the designed access path when a GEA stent with and without pin fixation is used to access tooth #8 with PCO. Materials and Methods: A 3-D printed maxillary model of an anonymous patient had a GEA stent designed using coDiagnonstiX software. The stent extended from tooth #3 to tooth #14 with the guide sleeve over tooth #8. Tooth #8 with no calcification, calcification to the cervical third, and calcification to the middle third of the RCS were designed in the coDiagnostiX software. Tooth #8 will be accessed using a 1.3 mm drill that fits a 1.3 mm sleeve used for both access and pin fixation. 15 of the 30 GEA samples will utilized pin fixation, while the other 15 samples did not utilize pin fixation. Following GEA in all 30 samples a CBCT was taken of each sample. Each post-operative CBCT was aligned with the pre-operative CBCT in the coDiagnostiX software. The coDiagnostiX software was able to calculate the degree of deviation and difference in 3D offset between the base and apical tip of the drill during GEA. Paired t-tests were used to test each group for significant differences in 3D offset between base and tip. Two-way ANOVA was used to evaluate the effects of pin fixation and calcification on the degree of deviation and the deviation of 3D offset of the entry point and tip. Results: There was a significant interaction between use of pin fixation and calcification level on the degree of deviation of GEA. GEA with pin fixation had a significantly larger degree of deviation than GEA without pin fixation with calcification extending to the middle third of the RCS. GEA with and without pin fixation did not have a significant difference when calcification extended to the cervical third of the RCS or no calcification was present. There was a significant interaction between use of pin fixation and calcification level on 3D offset difference. GEA with pin fixation had a significantly larger 3D offset difference than GEA with no pin fixation for calcification in the middle third of the RCS. For GEA with and without pin fixation there was no significant difference when calcification extended to the cervical third of the RCS or no calcification was present. Conclusion: The use of pin fixation did not result in a decrease of degree of deviation or difference in 3D offset during GEA access. It can be concluded that the use of pin fixation is not necessary for GEA of teeth with PCO when a full dentition is present to provide stability and retention of the stent. / 2022-06-21
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Evaluating the use of 3D imaging in creating a canal-directed endodontic access

Maru, Avni Mahendra 09 June 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: During root canal treatment (RCT), an opening is made through the crown of the tooth to access and to disinfect the root canal system (RCS). Traditional endodontic access (TEA) may sacrifice tooth structure and weaken the tooth. Cone beam computed tomography (CBCT) provides information about the exact location of the root canals. This information can be used for the design of a canal-directed endodontic access (CDEA). It may also be used for the 3D printing of an acrylic endodontic stent that could help to create a conservative CDEA. Objective: 1) Evaluate the ability of the Dolphin 3D imaging software to assist in creating a CDEA; 2) Compare tooth structure loss in a CDEA to that in a TEA by measuring the volume of remaining tooth structure, surface area of the access opening at the occlusal, and remaining dentin thickness at the CEJ. Materials and Methods: Thirty extracted human mandibular premolars were used. Teeth with large, wide canals were excluded. CBCT images will be taken for all teeth using Kodak 9000. Fifteen teeth were randomly assigned to the TEA group and 15 teeth were assigned to the CDEA group. The CDEA path was mapped using Dolphin 3D imaging software. Acrylic access stents were designed using Rhino 3D software and printed using a 3D printer. The teeth were accessed through the corresponding stents. The 15 teeth that are part of the traditional access group were accessed without a stent. A CBCT scan was taken post-access for all 30 teeth. Wilcoxon Rank Sum Tests were performed to compare the following outcomes for the two groups: the volume of remaining tooth structure, the surface area of the access opening at the occlusal, and remaining dentin thickness at the CEJ. Results: The remaining dentin thickness (percent loss) was not significantly larger for TEA than for CDEA. The surface area (post-treatment) was significantly larger for TEA than for CDEA, and volume (percent loss) was significantly larger for TEA than for CDEA. Conclusion: The use of the CBCT and Dolphin 3D imaging provided an accurate and more conservative CDEA with the guide of an acrylic stent.

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