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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.
91

Estudo in vivo e in vitro da incidência de bifurcação do canal radicular de incisivos inferiores pelo método radiográfico digital direto

Oliveira, Simone Helena Gonçalves de [UNESP] January 1900 (has links) (PDF)
Made available in DSpace on 2015-12-10T14:24:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2002. Added 1 bitstream(s) on 2015-12-10T14:30:41Z : No. of bitstreams: 1 000183138.pdf: 3546568 bytes, checksum: b8086168504f1d987c48cb7ff6b2b100 (MD5) / A morfologia da raiz dos incisivos inferiores possui um sulco longitudinal mesial e distal que pode condicionar a bifurcação de seu canal radicular. A proposta neste trabalho é estudar in vivo e in vitro a incidência de bifurcação do canal radicular dos incisivos inferiores com a utilização do radiovisiography. No estudo in vivo analisamos quatrocentos dentes, sendo realizadas radiovisiografias ortorradiais da região de incisivos e da região de caninos, onde visualizamos os incisivos com desvio de 20° distalmente. No estudo in vitro foram utilizados duzentos incisivos inferiores posicionados em um modelo, simulando o arco dental inferior, sendo radiovisiografados no sentido vestíbulo-lingual e posteriormente no sentido mésio-distal. As radiovisiografias foram visualizadas no monitor do aparelho onde analisamos a presença de canal único, canal bifurcado e canal com características indicativas de bifurcação, que correspondem à diminuição da radiolucidez cérvico-apical e à presença de linhas radiolúcidas dispostas longitudinalmente à raiz. Os resultados mostraram que 17,5% dos dentes do estudo in vivo e 15% dos dentes do estudo in vitro, que foram radiovisiografados no sentido vestíbulo-lingual, apresentaram bifurcação ou indicativos de bifurcação. No estudo in vitro, no sentido mésio-distal, encontramos 20% de bifurcação. Concluímos que a utilização da técnica de distalização do feixe de raios-X permite detectar grande percentagem dos casos de canais radiculares bifurcados ou com indicativos de bifurcação dos incisivos inferiores com a utilização do radiovisiography / The morphology of the root of the inferior incisors have a longitudinal, meslal and distal furrow that can condition the bifurcation of its root canal. The objetive of this work is to study in vivo and in vitro the incidence of the bifurcation of the root canal of the inferior incisors using radiovisiography. On the in vivo study, four hundred teeth were analyzed and orthoradial radiovisiographles of the incisors region and canines region were done where incisors with a 20º distal deviation could be seen. On the in vitro study, two hundred inferior incisors were used positioned in a mould, simulating the inferior dental arch and were radiovisiographed on the bucco-lingual direction and later, on the mesio-distal direction. The raradiovisiographies were visualized on the device monitor where the presence of an only canal, a bifurcated canal and a canal with bifurcation characteristics were analyzed. They correspond to the decrease in radiolucity and to the presence of radiolucidity lines disposed longitudinally to the root. The results show that 17,5% of the teeth on the in vivo study and 15% of the teeth on the in vitro study that were radiovisiographed on the bucco-lingual direction presented bifurcation or signs of bifurcation. On the in vitro study, on the mesiodistal direction, we found 20% of bifurcation. We can conclude that the use of the dislalization of the X-rays shaft technique allows us to delect a great percentage of cases of bifurcated root canals or cases with signs of bifurcation of the inferior incisors with the use of radiovisiography
92

Avaliação microscópica do preparo apical de canais radiculares curvos pela instrumentação manual rotatória e mecanizada rotatória e oscilatória utilizando o sistema Protaper Universal

Aguirre Balseca, Guillermo Mauricio [UNESP] 19 March 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-19Bitstream added on 2014-06-13T18:42:18Z : No. of bitstreams: 1 aguirrebalseca_gm_dr_arafo.pdf: 427440 bytes, checksum: 6a29eee07df8a7450c6daf136c0420c7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo avaliou o preparo apical, em canais curvos de raízes mesiais de molares inferiores humanos, sobre três diferentes aspectos: a área, o perímetro e o deslocamento, a partir da utilização do Sistema Protaper Universal empregando-se três diferentes cinemáticas: instrumentação manual e mecanização rotatória e oscilatória. Para isso, trinta e nove canais de raízes mesiais de molares inferiores humanos foram previamente selecionados. Todos eles apresentavam-se viáveis e não tratados endodonticamente, apresentando curvatura entre 30 e 40 graus e raio de 8 a 10 mm. As amostras foram preparadas, inseridas em blocos de resina, seccionadas transversalmente, na região apical e, em seguida, fotografadas com o auxílio de um microscópio digital (Olimpus Mic-D), para que posteriormente, fosse possível mensurar a variação dos aspectos propostos, pré e pós-instrumentação. Com a análise dos resultados obtidos, pode-se concluir que não foi encontrada nenhuma diferença estatística entre as três cinemáticas: instrumentação manual e mecanização rotatória e oscilatória, empregadas aos instrumentos do Sistema Protaper Universal. O único dado estatisticamente relevante é que o instrumento de acabamento F3, quando empregada a cinemática oscilatória, promoveu um deslocamento maior do que quando a ele foi empregada a cinemática manual. Além disso, recomendamos o emprego da cinemática manual com os instrumentos do Sistema Protaper Universal, visto que sem incidências estatiísticas, foi a que obteve um maior aumento de área e perímetro, promovendo um menor deslocamento apical durante a fase de preparo biomecânico de canais radiculares com curvatura severa. / This study evaluated the apical preparation, in curved mesial root canals of human mandibular molars, through three different features: area, perimeter and displacement (transportation), applying to it three different kinematics to Protaper Universal System: manual instrumentation, mecanically rotatory and oscilatory. Thirty-nine mesial root canals of human mandibular molars were previously selected. All of them were viables and without endodontic treatment, presenting angles of curvature between 30 degrees and 40 degrees, beyond the radius of 8 to 10 mm . The samples were prepared, invested into resin blocks and transversally seccioned in apical region. Afterwards, a digital microscope (Olimpus Mic-D) was used to take pictures, pre and post-instrumentation, for subsequently measurement of the proposed features variation. All results were analysed and there was no statistically difference between three kinematics (manual instrumentation and mecanical rotatory and oscilatory) applyed to the Protaper Universal System´s instruments. Data statistically relevant which should be considered is that the finishing file F3 applyed the oscilatory kinematic, promoved a bigger transportation when compared to this file applyed the manual kinematic. Moreover, the manual kinematic applyed to the instruments of Protaper Universal system is recommended, since there is no statistical evidences it was the one which had a greater increase of area and perimeter, promoving a least apical displacement during the biomecanical prepare in root canal with several curvature.
93

Estudo in vivo e in vitro da incidência de bifurcação do canal radicular de incisivos inferiores pelo método radiográfico digital direto /

Oliveira, Simone Helena Gonçalves de. January 2002 (has links)
Orientador: Luiz Cesar de Moraes / Banca: Mônica Campos Serra / Banca: Emiko Saito Arita / Banca: Horácio Faig Leite / Banca: Julio Cezar de Melo Castilho / Resumo: A morfologia da raiz dos incisivos inferiores possui um sulco longitudinal mesial e distal que pode condicionar a bifurcação de seu canal radicular. A proposta neste trabalho é estudar in vivo e in vitro a incidência de bifurcação do canal radicular dos incisivos inferiores com a utilização do radiovisiography. No estudo in vivo analisamos quatrocentos dentes, sendo realizadas radiovisiografias ortorradiais da região de incisivos e da região de caninos, onde visualizamos os incisivos com desvio de 20° distalmente. No estudo in vitro foram utilizados duzentos incisivos inferiores posicionados em um modelo, simulando o arco dental inferior, sendo radiovisiografados no sentido vestíbulo-lingual e posteriormente no sentido mésio-distal. As radiovisiografias foram visualizadas no monitor do aparelho onde analisamos a presença de canal único, canal bifurcado e canal com características indicativas de bifurcação, que correspondem à diminuição da radiolucidez cérvico-apical e à presença de linhas radiolúcidas dispostas longitudinalmente à raiz. Os resultados mostraram que 17,5% dos dentes do estudo in vivo e 15% dos dentes do estudo in vitro, que foram radiovisiografados no sentido vestíbulo-lingual, apresentaram bifurcação ou indicativos de bifurcação. No estudo in vitro, no sentido mésio-distal, encontramos 20% de bifurcação. Concluímos que a utilização da técnica de distalização do feixe de raios-X permite detectar grande percentagem dos casos de canais radiculares bifurcados ou com indicativos de bifurcação dos incisivos inferiores com a utilização do radiovisiography / Abstract: The morphology of the root of the inferior incisors have a longitudinal, meslal and distal furrow that can condition the bifurcation of its root canal. The objetive of this work is to study in vivo and in vitro the incidence of the bifurcation of the root canal of the inferior incisors using radiovisiography. On the in vivo study, four hundred teeth were analyzed and orthoradial radiovisiographles of the incisors region and canines region were done where incisors with a 20º distal deviation could be seen. On the in vitro study, two hundred inferior incisors were used positioned in a mould, simulating the inferior dental arch and were radiovisiographed on the bucco-lingual direction and later, on the mesio-distal direction. The raradiovisiographies were visualized on the device monitor where the presence of an only canal, a bifurcated canal and a canal with bifurcation characteristics were analyzed. They correspond to the decrease in radiolucity and to the presence of radiolucidity lines disposed longitudinally to the root. The results show that 17,5% of the teeth on the in vivo study and 15% of the teeth on the in vitro study that were radiovisiographed on the bucco-lingual direction presented bifurcation or signs of bifurcation. On the in vitro study, on the mesiodistal direction, we found 20% of bifurcation. We can conclude that the use of the dislalization of the X-rays shaft technique allows us to delect a great percentage of cases of bifurcated root canals or cases with signs of bifurcation of the inferior incisors with the use of radiovisiography / Doutor
94

Influência do emprêgo de quelantes, seguido ou não de inativadores, na retenção de pinos em canais dentinários artificialmente preparados /

Camargo, Hed Arruda. January 1982 (has links)
Banca: Jaime Maurício leal / Banca: João Humberto Antônio / Banca: Alberto Sansiviero / Banca: Clóvis Monteiro Bramante / Banca: Antonio Fernando Tommasi / Resumo: Não disponível / Abstract: Not available
95

Avaliação microscópica do preparo apical de canais radiculares curvos pela instrumentação manual rotatória e mecanizada rotatória e oscilatória utilizando o sistema Protaper Universal /

Aguirre Balseca, Guillermo Mauricio. January 2008 (has links)
Orientador: Idomeo Bonetti Filho / Banca: Renato de Toledo Leonardo / Banca: Fabio Luiz Camargo Villela Berbert / Banca: Luciana Arantes Porto Carvalho / Banca: Eloi Dezan Junior / Resumo: Este estudo avaliou o preparo apical, em canais curvos de raízes mesiais de molares inferiores humanos, sobre três diferentes aspectos: a área, o perímetro e o deslocamento, a partir da utilização do Sistema Protaper Universal empregando-se três diferentes cinemáticas: instrumentação manual e mecanização rotatória e oscilatória. Para isso, trinta e nove canais de raízes mesiais de molares inferiores humanos foram previamente selecionados. Todos eles apresentavam-se viáveis e não tratados endodonticamente, apresentando curvatura entre 30 e 40 graus e raio de 8 a 10 mm. As amostras foram preparadas, inseridas em blocos de resina, seccionadas transversalmente, na região apical e, em seguida, fotografadas com o auxílio de um microscópio digital (Olimpus Mic-D), para que posteriormente, fosse possível mensurar a variação dos aspectos propostos, pré e pós-instrumentação. Com a análise dos resultados obtidos, pode-se concluir que não foi encontrada nenhuma diferença estatística entre as três cinemáticas: instrumentação manual e mecanização rotatória e oscilatória, empregadas aos instrumentos do Sistema Protaper Universal. O único dado estatisticamente relevante é que o instrumento de acabamento F3, quando empregada a cinemática oscilatória, promoveu um deslocamento maior do que quando a ele foi empregada a cinemática manual. Além disso, recomendamos o emprego da cinemática manual com os instrumentos do Sistema Protaper Universal, visto que sem incidências estatiísticas, foi a que obteve um maior aumento de área e perímetro, promovendo um menor deslocamento apical durante a fase de preparo biomecânico de canais radiculares com curvatura severa. / Abstract: This study evaluated the apical preparation, in curved mesial root canals of human mandibular molars, through three different features: area, perimeter and displacement (transportation), applying to it three different kinematics to Protaper Universal System: manual instrumentation, mecanically rotatory and oscilatory. Thirty-nine mesial root canals of human mandibular molars were previously selected. All of them were viables and without endodontic treatment, presenting angles of curvature between 30 degrees and 40 degrees, beyond the radius of 8 to 10 mm . The samples were prepared, invested into resin blocks and transversally seccioned in apical region. Afterwards, a digital microscope (Olimpus Mic-D) was used to take pictures, pre and post-instrumentation, for subsequently measurement of the proposed features variation. All results were analysed and there was no statistically difference between three kinematics (manual instrumentation and mecanical rotatory and oscilatory) applyed to the Protaper Universal System's instruments. Data statistically relevant which should be considered is that the finishing file F3 applyed the oscilatory kinematic, promoved a bigger transportation when compared to this file applyed the manual kinematic. Moreover, the manual kinematic applyed to the instruments of Protaper Universal system is recommended, since there is no statistical evidences it was the one which had a greater increase of area and perimeter, promoving a least apical displacement during the biomecanical prepare in root canal with several curvature. / Doutor
96

Comparison of time taken and breakage of six different endodontic systems to prepare molar teeth

Brittain, Roger January 2006 (has links)
Magister Scientiae Dentium - MSc(Dent) / The purpose of this study was to determine duration time, breakage and apical displacement, whilst using six different endodontic filing systems to prepare molar teeth. A total of 96 molar teeth were used in the study, divided equally, ie 16 teeth per system selected randomly, totalling 48 canals per system. A standardised access cavity was prepared for all the teeth before selection. The canals were filed according to the manufacturers’ guidelines. The result showed that PROTAPER®, K3™ and the combination of: HERO Shaper®, HERO Apical® and Endoflare® (Referred from hereon as HERO System for convenience) were statistically faster than PROFILE® and FlexMaster®, which were in turn faster than AETTM. Although breakage did occur in K3™ and HERO System this was not deemed statistically significant. Apical displacement occurred in the form of Type 1 in the AETTM, PROFILE® and HERO System, but once again this was not statistically significant. It was concluded that more aggressive cutting features such as a positive rake angle, pyramidal shaped tip, progressive taper and absence of radial lands, if present, could have enabled K3™, HERO System and PROTAPER® to have faster times, and in addition these features did not compromise these systems with regard to apical foramina transportation and breakage. / South Africa
97

Bond strength of calcium silicate based bioceramic sealers to dentin

Tomaszewska, Marta Agnieszka 13 June 2021 (has links)
OBJECTIVE: The aim of this study was to compare available bioceramic sealers and resin based sealer on their push out and shear bond strength. MATERIALS AND METHODS: Three calcium silicate based bioceramic sealers: Endosequence BC sealer (Brasseler), BioRoot RCS (Septodont) and Edge Bioceramic Sealer (EdgeEndo) and one resin based sealer (AH Plus) were included in this study. Twelve single rooted teeth were decoronated, treated, and obturated with one of the tested sealers (n=3). After one-week incubation, teeth were sectioned into 1 mm thick slices and submitted to push out bond strength test on a universal testing machine. 48 teeth were sectioned horizontally to uncover the dentin and embedded in epoxy resin (n=12 per sealer). Polyethylene tubes (3 mm diameter) placed on the dentin were filled with one of the tested sealers. After one-week incubation, specimens were submitted to a shear bond strength test. Data was analyzed by one-way ANOVA and all pairs comparison using Tukey-Kramer HSD test with the alpha set as 0.05. RESULTS: The calculated mean push out bond strengths were 4.48±2.23 MPa, 3.19±2.61 MPa, 2.82±1.70 MPa and 7.56±5.09 MPa for BioRoot RCS, Endosequence BC Sealer, Edge Bioceramic Sealer and AH Plus respectively, while the shear bond strengths were 8.56±4.55 MPa, 5.52±4.38 MPa, 3.93±2.64 MPa and 36.71±14.39MPa in the same order. CONCLUSION: With the limitation of this study we concluded that bioceramic sealers present lower bond strength than resin based sealer and that there is no significantly different bond strength to root dentin amongst bioceramic sealers themselves.
98

Development of antibiotic resistance due to chromosomal mutation caused by AH26 endodontic sealer

Hales, Jason J., January 2002 (has links)
Thesis (M.S.)--West Virginia University, 2002. / AH26 is a registered trademark. Title from document title page. Document formatted into pages; contains vii, 55 p. : ill. (some col.). Includes a video file in the AVI format. Vita. Includes abstract. Includes bibliographical references (p. 48-53).
99

An in vitro assessment of an engineered cationic antimicrobial peptide (eCAP) against planktonic strains of E. faecalis

McBride, Kent Alexander. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 33 p. : col. ill. Vita. Includes abstract. Includes bibliographical references (p. 26-31).
100

A model combining fluorescent microscopy and culture inhibition to evaluate bacterial activity of calcium hydroxide medicaments

Connor, Catherine Erwin. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains vii, 82 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 47-52).

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