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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.
121

Observations of Trends and Successes of Revascularization Therapy at Virginia Commonwealth University: A Retrospective Study

Sedwick, Richard W 01 January 2018 (has links)
The aim of this study was to determine the trends in protocol, success rates, and consistency in follow up of revascularization procedures in a controlled environment. Patients of the Virginia Commonwealth University School of Dentistry were identified who were offered revascularization therapy as a treatment option on immature permanent teeth from January 1, 2010 to May 31, 2017. A total of 77 patients and 78 teeth were evaluated for revascularization therapy. For patients accepting treatment, records were reviewed for outcome assessment and consistency of follow up. A total of 30 patients (31 teeth) were treated following revascularization protocols, with only 20 patients (21 teeth) returning for follow up. Six of the 21 teeth needed some form of additional therapy due to patients remaining symptomatic, however 15/21 exhibited varying levels of success. Recall rate was 67.7%. With a success rate of 71.4%, revascularization therapy should continue to be considered for all patients with teeth having necrotic pulps and immature root apices. However, changes to recall protocols need to be improved in order to better monitor the status of teeth that undergo revascularization therapy.
122

Efeito de probióticos no desenvolvimento de lesão periapical induzida em ratos /

Silva, Leopoldo Cosme. January 2019 (has links)
Orientador: João Eduardo Gomes Filho / Banca: Luciano Tavares Angelo Cintra / Banca: Francine Benetti / Banca: Christiane Men Martins / Banca: Paulo Carvalho Tobias Duarte / Resumo: Objetivo: O objetivo do presente estudo foi avaliar o efeito da administração sistêmica de probióticos nos parâmetros hematológicos, microbiológicos do canal radicular e da saliva e no desenvolvimento da periodontite apical (PA) induzida em ratos. Material e Métodos: Foram utilizados 24 ratos Wistar machos. PA foi induzida nos primeiros molares inferiores e superiores (lado esquerdo e direito). Os animais foram divididos em 3 grupos: controle, Lactobacillus rhamnosus e Lactobacillus acidophilus. Os probióticos foram administrados por gavagem (109 unidades formadoras de colônias (CFU)) diluídas em 5 mL de água durante o período de desenvolvimento da PA (30 dias). No trigésimo dia, foi realizada punção cardíaca para análise de hemograma, cálcio, fósforo e concentração de fosfatase alcalina no sangue. Além disso, foi realizada análise microbiológica do conteúdo do canal radicular e da saliva. Em seguida, os animais foram eutanasiados e a mandíbula e maxila foram removidas para análise da PA através da microtomografia computadorizada; análises histopatológicas (hematoxilina - H&E) e de imunomarcação para interleucina 10 (IL-10), interleucina 1 beta (IL-1β), interleucina 6 (IL-6), ligante do recetor ativador do fator nuclear kappa B (RANKL), osteoprotegerina (OPG) e fosfase ácida resistente ao tataráto (TRAP). Os dados foram estatisticamente analisados com nível de significância de 5%. Resultados: A fosfatase alcalina foi maior nos grupos que consumiram probióticos (p>0.05). A con... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Aim:The objective of the present study was to evaluate the effect of systemic administration of probiotics on haematological, microbiological parameters of the root canal and saliva and on the development of apical periodontitis (AP) induced in ratsMaterials and Methods:Twenty-four male Wistar rats were used. PA was induced in the lower and upper first molars (left and right side). The animals were divided into three groups: control, Lactobacillus rhamnosusand Lactobacillus acidophilus. Probiotics were administered by gavage (109 colony forming units (CFU)) diluted in 5 mL of water during the developmental period of PA (30 days). On the thirtieth day, cardiac puncture was performed for hemogram, calcium, phosphorus and alkaline phosphatase concentration in the blood. In addition, a microbiological analysis of the root canal and saliva contents was performed. Afterwards, the animals were euthanized and the mandible and maxilla were removed for analysis of PA by computerized microtomography; interleukin 10 (IL-10), interleukin 1 beta (IL-1β), interleukin 6 (IL-6), receptor activator of NF-κB ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP). The data were statistically analyzed with significance level of 5%.Results:Alkaline phosphatase was higher in the groups that consumed probiotics (p>0.05). The total count of microorganisms in the root canal/saliva, inflammatory infiltrate and immunolabeling for IL-1β and IL-6 in BP were lower in the probi... (Complete abstract click electronic access below) / Doutor
123

Comparative efficacy of endodontic medicaments against Enterococcus faecalis biofilms.

Plutzer, Barbara January 2009 (has links)
It is well established that bacteria cause pulpal and periradicular disease (Kakehashi et al. 1965). Of the bacteria recovered from failing root canals, Enterococcus faecalis is one of the most prevalent species (Molander et al. 1998; Sundqvist et al. 1998). Many laboratory studies have investigated the effectiveness of root canal irrigants and medicaments against E. faecalis. Most used planktonic cultures, which are not representative of the in vivo growth conditions of an infected root canal system, where bacteria grow as a biofilm adhering to the dentinal wall (Nair 1987). Organisation of bacteria within biofilms confers a range of phenotypic properties that are not evident in their planktonic counterparts, including a markedly reduced susceptibility to antimicrobial killing (Wilson 1996). Objectives: The aims of this study were: 1) To compare the efficacy of commonly used endodontic medicaments against E. faecalis cultured as a biofilm. The medicaments tested were Ledermix paste, calcium hydroxide, Odontopaste, 0.2% chlorhexidine gel and 50:50 combinations of Ledermix/calcium hydroxide and Odontopaste/calcium hydroxide. 2) To compare the antimicrobial effect achieved through exposure to endodontic medicaments with that achieved by exposure to a constant concentration of sodium hypochlorite for varying times. Methods: A biofilm was established using a continuous flow cell. E. faecalis inoculum was introduced into the flow cell and allowed to establish on human dentine slices over 4 weeks. Each test medicament was introduced into the flow cell for a period of 24 or 48 hours, while sodium hypochlorite was evaluated after 1, 10, 30 and 60 minutes. Biofilms were harvested by sonication in sterile PBS. Cellular protein levels were measured to quantitate the amount of biofilm harvested. Cellular viability was determined using serial plating. The number of colony forming units was then adjusted for cellular protein levels to allow treatment protocols to be compared. Qualitative SEM analyses of the biofilm was performed following exposure to each test agent. Results: Sodium hypochlorite was the only agent that achieved total bacterial elimination. Ledermix and Odontopaste had no significant effect on the E. faecalis biofilm, while calcium hydroxide and 50:50 combinations of calcium hydroxide with either Ledermix or Odontopaste were able to reduce viability by > 99%. Conclusion: When used in isolation, antibiotic containing medicaments had no appreciable effect on the viability of Enterococcus faecalis. Sodium hypochlorite remains the gold standard for bacterial elimination in root canal therapy. / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2009
124

Comparative efficacy of endodontic medicaments against Enterococcus faecalis biofilms.

Plutzer, Barbara January 2009 (has links)
It is well established that bacteria cause pulpal and periradicular disease (Kakehashi et al. 1965). Of the bacteria recovered from failing root canals, Enterococcus faecalis is one of the most prevalent species (Molander et al. 1998; Sundqvist et al. 1998). Many laboratory studies have investigated the effectiveness of root canal irrigants and medicaments against E. faecalis. Most used planktonic cultures, which are not representative of the in vivo growth conditions of an infected root canal system, where bacteria grow as a biofilm adhering to the dentinal wall (Nair 1987). Organisation of bacteria within biofilms confers a range of phenotypic properties that are not evident in their planktonic counterparts, including a markedly reduced susceptibility to antimicrobial killing (Wilson 1996). Objectives: The aims of this study were: 1) To compare the efficacy of commonly used endodontic medicaments against E. faecalis cultured as a biofilm. The medicaments tested were Ledermix paste, calcium hydroxide, Odontopaste, 0.2% chlorhexidine gel and 50:50 combinations of Ledermix/calcium hydroxide and Odontopaste/calcium hydroxide. 2) To compare the antimicrobial effect achieved through exposure to endodontic medicaments with that achieved by exposure to a constant concentration of sodium hypochlorite for varying times. Methods: A biofilm was established using a continuous flow cell. E. faecalis inoculum was introduced into the flow cell and allowed to establish on human dentine slices over 4 weeks. Each test medicament was introduced into the flow cell for a period of 24 or 48 hours, while sodium hypochlorite was evaluated after 1, 10, 30 and 60 minutes. Biofilms were harvested by sonication in sterile PBS. Cellular protein levels were measured to quantitate the amount of biofilm harvested. Cellular viability was determined using serial plating. The number of colony forming units was then adjusted for cellular protein levels to allow treatment protocols to be compared. Qualitative SEM analyses of the biofilm was performed following exposure to each test agent. Results: Sodium hypochlorite was the only agent that achieved total bacterial elimination. Ledermix and Odontopaste had no significant effect on the E. faecalis biofilm, while calcium hydroxide and 50:50 combinations of calcium hydroxide with either Ledermix or Odontopaste were able to reduce viability by > 99%. Conclusion: When used in isolation, antibiotic containing medicaments had no appreciable effect on the viability of Enterococcus faecalis. Sodium hypochlorite remains the gold standard for bacterial elimination in root canal therapy. / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2009
125

Dynamic properties of nickel-titanium instruments /

Boonrat Sattapan. January 1997 (has links)
Thesis (M.D. Sc.)--University of Melbourne, School of Dental Science, 1998. / Typescript (photocopy). Includes bibliographical references.
126

A study of the structural, dimensional, and physical characteristics of root canal instruments thesis submitted as partial fulfillment ... /

Heuer, Michael A. January 1959 (has links)
Thesis (M.S.)--University of Michigan, 1959.
127

A study of the structural, dimensional, and physical characteristics of root canal instruments thesis submitted as partial fulfillment ... /

Heuer, Michael A. January 1959 (has links)
Thesis (M.S.)--University of Michigan, 1959.
128

Standardized endodontic technique morphometric and clinical studies /

Kerekes, Kasmer. January 1980 (has links)
Thesis (doctoral)--University of Oslo, 1980. / Includes reprints of 7 papers by author.
129

Ação antibacteriana da cetramida associada às solucões irrigadoras sobre Enterococcus Faecalis

Nascimento, Camila Almeida [UNESP] 11 March 2013 (has links) (PDF)
Made available in DSpace on 2014-08-13T14:50:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-11Bitstream added on 2014-08-13T18:01:16Z : No. of bitstreams: 1 000731950_20150311.pdf: 325288 bytes, checksum: 324db53ef4e3d775e299c6c4c92a035e (MD5) Bitstreams deleted on 2015-03-12T12:02:42Z: 000731950_20150311.pdf,Bitstream added on 2015-03-12T12:03:13Z : No. of bitstreams: 1 000731950.pdf: 1695739 bytes, checksum: 36607b7a254d4ab1aee0e89e07392e36 (MD5) / O objetivo do estudo foi avaliar a ação das soluções de hipoclorito de sódio e clorexidina associadas à cetramida e do QMiX, produto comercial que combina clorexidina, EDTA e cetramida, sobre Enterococcus faecalis (ATCC 29212) em fase planctônica e biofilme. As soluções avaliadas foram: G1: Hipoclorito de sódio (NaOCl) a 2,5%; G2: NaOCl a 2,5% + cetramida (CTR) a 0,2%; G3: Clorexidina (CLX) a 2%; G4: CLX a 2% + CTR a 0,2%; G5: CTR a 0,2%; G6: QMiX. Como controle negativo foi utilizada solução salina. O estudo foi dividido em dois capítulos. No capítulo 1, foi realizada a avaliação da atividade antibacteriana sobre os micro-organismos em fase planctônica e biofilme. Para o contato direto com E. faecalis em fase planctônica, 50 μl da suspensão bacteriana foram colocados em tubos contendo 1,45 mL de cada solução irrigadora ou associações e, após os períodos de 1 e 3 minutos foram utilizadas soluções neutralizantes da ação antimicrobiana dos irrigantes. Em seguida, foi realizada diluição decimal seriada e plaqueamento em meio Tryptic Soy agar (TSa). Para a indução dos biofilmes foram utilizados blocos de dentina bovina como substrato no período de 14 dias. Os biofilmes foram colocados em contato com as soluções avaliadas, e transferidos para tubos de ensaio contendo soluções neutralizantes. Após agitação por 60 segundos para a suspensão das células remanescentes, foi realizada diluição decimal seriada e plaqueamento em TSa em triplicata. A incubação foi realizada em microaerofilia a 37°C por 24 horas e a análise efetuada por meio da contagem de UFC mL-1. Os resultados foram submetidos aos testes ANOVA e Tukey, com nível de significância de 5%. Todas as soluções irrigadoras e associações avaliadas eliminaram completamente os micro-organismos em fase planctônica. Sobre biofilme, somente NaOCl e NaOCl+CTR apresentaram 100% de eliminação bacteriana... / The aim of this study was to evaluate the action of conventional endodontic solutions such as sodium hypochlorite and chlorhexidine associated with cetrimide and QMiX, a commercial product composed by chlorhexidine, EDTA and cetrimide, on biofilm and planktonic phase of Enterococcus faecalis (ATCC 29212). The evaluated solutions were: G1: 2.5% Sodium Hypochlorite (NaOCl); G2: 2.5% NaOCl + 0.2% cetrimide (CTR); G3: 2% Chlorhexidine (CLX) 2%; G4: 2% CLX + 0.2% CTR; G5: 0.2% CTR; G6: QMiX. Saline solution was used as negative control. The study was divided into two chapters. In Chapter 1, the antibacterial activity of the solutions on microorganisms in planktonic phase and biofilm was evaluated. For direct contact with E. faecalis in planktonic phase, 50 μL of bacterial suspension were placed in tubes containing 1.45 mL of each irrigation solution or associations and after 1 and 3 minutes, neutralizing solutions were used to stop of the antimicrobial action of endodontic solutions. Decimal serial dilutions were performed and the suspensions were plated in Tryptic Soy agar medium (TSa). Dentin bovine blocks were used as substrate for induction of biofilms for 14 days. The biofilms were placed in contact with the solutions evaluated and transferred to test tubes containing neutralizing solution. After agitation for 60 seconds to suspend the remaining cells, decimal serial dilutions were performed and the suspensions were cultivated in triplicate on TSA plates. The incubation was held in microaerophilic at 37 ° C for 24 hours and the analysis was performed by counting CFU mL-1. The results were submitted to ANOVA and Tukey test, with significance level of 5%. All irrigating solutions and associations evaluated completely eradicated the microorganisms in planktonic phase. On biofilm, only NaOCl and NaOCl+CTR showed 100%- of bacterial elimination. CLX showed similar activity to CLX+CTR, CTR and QMiX after...
130

Avaliação de propriedades físico-químicas, mecânicas e antimicrobianos do MTA e cimento Portland associado a solução de nanopartículas de prata /

Vázquez García, Fernando Antonio. January 2014 (has links)
Orientador: Juliane Maria Guerreiro Tanomaru / Banca: Idomeo Bonetti Filho / Banca: Evandro Watanabe / Resumo: A substituição do óxido de bismuto por óxido de zircônio (ZrO2) e a adição de nanopartículas de prata (NPsAg) pode favorecer as propriedades físico-químicas mecânicas e antimicrobianas. Capítulo 1: Foram avaliados pH, solubilidade, tempo de presa, radiopacidade e resistência à compressão. Grupos: G1 - MTA Angelus; G2 - CP/ZrO2; G3 - MTA/NPsAg; G4 -CP/ZrO2/NPsAg. O pH foi analisado em pHmetro digital, a solubilidade pela perda de massa e o tempo de presa pelo teste de Gilmore. A resistência à compressão foi avaliada em ensaio mecânico. Para análise da radiopacidade, as amostras foram radiografadas com uma escala de alumínio. Os resultados foram submetidos aos testes ANOVA e Tukey (p<0,05). O G3 apresentou aumento de pH e diminuição da solubilidade e tempo do presa inicial e final. O G4 apresentou diminuição da solubilidade e aumento da resistência à compressão. A radiopacidade dos materiais foi superior a 4 mmAl. As associações G3 e G4 apresentam propriedades físico-químicas e mecânicas adequadas. Capítulo 2: Bactérias na forma planctônica foram colocadas sobre o cimento fresco e a análise foi realizada em espectrofotômetro. Na avaliação antibiofilme, os materiais foram colocados em contato com biofilme de E. faecalis formado sobre blocos de dentina e analisados pela contagem de unidades formadoras de colônia. Os resultados foram submetidos aos testes ANOVA e Tukey (p<0,05). Na forma planctônica, melhores resultados foram encontrados no G2 e G4. Maior redução de biofilme foi apresentada pelos G3 e G4. A incorporação de NPsAg ao CP e MTA, melhora a atividade antibacteriana e antibiofilme dos materiais à base de silicato de cálcio. / Abstract: The bismuth oxide replacement by zirconium oxide (ZrO2) and the addition of silver nanoparticles may improve the physicochemical, mechanic and antimicrobial properties. Chapter I: It was evaluated pH, solubility, setting time, radiopacity and compressive strength. Groups: G1-MTA Angelus; G2-PC/ZrO2; G3-MTA/NPsAg, G4-PC/ZrO2/NPsAg. The pH was measured with a digital pH meter, the solubility by the weight loss and the setting time was evaluated by Gilmore needle. Compressive strength was tested in universal testing machine. For radiopacity analysis material samples were radiographed alongside an aluminium step-wedge. The results were submitted to ANOVA and Tukey tests (p<0.05). The G3 showed a pH increase and a decrease of solubility and initial and final setting time. The G4 showed a decrease in solubility and an increase of compressive strength. All materials presented radiopacity greater than 4 mmAl. The G3 and G4 associations showed good physicochemical and mechanical properties. Chapter 2: For the first test bacterias in planktonic form were placed over fresh cement, and the analysis was performed in spectrophotometer. Also for the antibiofilm test, the samples were placed in direct contact with E. faecalis biofilm previously induced on bovine dentine and analysed by the counting of colony-forming units. The results were submitted to ANOVA and Tukey tests (p<0.05). On the planktonic form, the best results were showed by G2 and G4. The greater reduction of biofilm were showed by G3 and G4. The incorporation of NPsAg to PC and MTA improves the antibacterial and antbiofilm activity of calcium silicate cements. / Mestre

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