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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

Remoção parcial de tecido cariado em lesões de cárie profundas de dentes permanentes / Partial removal of carious dentine in deep caries lesion in the permanent dentition

Jardim, Juliana Jobim January 2010 (has links)
The partial removal of carious dentine was studied by means of a literature review and a multicenter randomized controlled clinical trial. The clinical trial compared the effectiveness of an alternative treatment for deep caries lesions and the stepwise excavation in Public Health Services in Brazil. The treatment consists of partial removal of carious dentine followed by restoration in one session. A cost-effectiveness analysis the two treatments was performed. The clinical performance of amalgam and resin restorations placed in deep caries lesions with or without decayed tissue beneath them was also evaluated. Inclusion criteria: patients with ≥ nine years old, permanent molars with deep caries lesions and absence of periapical alterations, pulp sensitivity; absence of spontaneous pain; negative percussion test. The subjects were assigned to: test-group - partial removal of carious dentine (PDR) and restoration, and control-group - stepwise excavation (SW). SW consists of partial removal of carious tissue, indirect pulp capping with calcium hydroxide cement; temporary filling; cavity re-opening after 60 days, removal of the remaining soft carious tissue and filling. Clinical and radiological exams were performed annually. The outcomes were: (1) pulp sensitivity to cold test and absence of periapical alterations, assuming those parameters as indicators of pulp vitality; and (2) success of the restoration. To determine the cost-effectiveness of the treatments, the discounted cash flow method was adopted. The data were submitted to Kaplan-Meier, Log-rank test and logistic regression analysis, P<0.05. There were performed 299 treatments, 146 SW and 153 tests. There were no differences between the groups regarding baseline characteristics - age, gender and family income. The number of teeth evaluated after one and two years were 180 and 122. After one year of treatment performance, the therapy success rates were 97.9% and 74.1% of success in test and control groups respectively (P<0.000). After 2 years of follow-up, therapy survival rates of PDR and SW were 93.7% and 73.3% respectively (P=0.000). A total of 29 therapeutic failures were observed: PDR group - pulpitis (n=3), osteitis (n=1), hyperemia (n=2); SW group - pulpitis (n=15), necrosis (n=6), extraction (n=1) and restoration fracture (n=1). None of the variables studied showed a significant causal influence on the success rate, besides the type of treatment. After two year of follow-up, 181 restorations had been evaluated, 86 from the SW group and 95 from the PDR group; 65.8% were from the resin composite group and 34.2% were amalgam restorations. The survival analysis of the treatment associated with the filling material showed no difference in the rate of success (P=0.564). Regarding the treatment, both groups presented a similar rate of success: SW=95.3% and PDR=94.7% (P=0.928). Resin composite restorations presented 96.8% of success and amalgam restorations presented 94.1% of success (P=0.446). The reason for failure was fracture of filling material. The PDR provides an economy of R$ 143.37 (67.78%) per treatment compare to SW and 2.39% in the overall economy in the annual cost of the public health center. Partial caries removal could be performed as definitive treatment and the procedure of re-opening the cavity to remove the residual infected dentine is not necessary. The maintenance of carious dentine does not interfere in the maintenance of pulp vitality. The presence of decayed tissue in deep caries lesions does not seem to interfere with the survival of the restorations. Performing the partial removal of carious dentine in one session generates benefits for the public finances (direct economy), for the public health services (increase in number of treatments performed) and for the patients (comfort and time).
62

La porosité des résines composites utilisées en odontologie : étude de son origine et évaluation de son influence sur différentes propriétés / The porosity of resin composites used in dentistry : study of its origin and evaluation of its influence on various properties

Balthazard, Rémy 11 December 2015 (has links)
Depuis plus de 60 ans, les résines composites à usage dentaire n’ont cessé d’évoluer vers des matériaux toujours plus fonctionnels et esthétiques. Toutefois, l’obtention du matériau de restauration idéal présentant des propriétés mécaniques et physico-chimiques optimales reste encore aujourd’hui un défi de taille. La nature et la proportion des monomères, le type, la taille et le taux de charges, la qualité des liens entre charges et matrice et la présence de porosités au sein des matériaux apparaissent comme des éléments pouvant influencer ces propriétés. Afin d’avancer dans le compréhension de l’impact de ces différents facteurs, plusieurs études ont été entreprises à l’aide de trois résines composites commerciales de viscosités différentes : une résine de viscosité élevée (Filtek P60 – 3M ESPE), une résine de viscosité moyenne (Grandio – Voco) et une résine de viscosité faible (Filtek Supreme XTE – 3M ESPE). L’influence de la manipulation clinique des matériaux sur le taux et le volume des porosités a été évaluée à l’aide de la tomographie 3D à rayons X. La manipulation augmente le pourcentage et diminue le volume moyen des porosités. En outre, plus le matériau est fluide et plus il présente de porosités en son sein. Deux groupes d’échantillons ont été réalisés afin d’évaluer l’influence de la porosité sur le comportement mécanique et physico-chimique des matériaux : l’un à partir des matériaux simplement extrudés des seringues et l’autre au sein duquel nous avons réalisé une adjonction artificielle de porosités. La contrainte de polymérisation à été déterminée à l’aide d’une machine de traction, l’absorption/solubilité a été mesurée en respectant le cadre ISO 4049, le comportement mécanique vrai a été évalué en traction à l’aide du système VidéoTractionTM, les comportements apparents en compression et flexion ont été étudiés respectivement à l’aide d’une machine de compression et d’une machine de flexion 3 points. Les différents constituants organiques et minéraux apparaissent comme des éléments déterminants dans le comportement physico-chimique et mécanique des matériaux. La porosité initiale est également un facteur prépondérant dans l’explication dudit comportement. Son influence n’est cependant pas proportionnelle à son taux puisque l’ajout de porosités artificielles n’influence pas significativement les résultats / For the past 60 years, dental resin composites have been constantly evolving, becoming increasingly functional and aesthetic materials. However, obtaining the ideal dental restorative material, with optimum mechanical and physicochemical properties, is still a significant challenge today. The nature and proportion of the monomers, the type, size and content of fillers, the quality of the bonds between the fillers and the matrix and the presence of porosities inside materials all emerge as aspects that can influence these properties. To improve our understanding of the impact of these various factors, a number of studies have been undertaken using three commercially-available resin composites with different viscosities: one high-viscosity resin (Filtek P60 – 3M ESPE), one moderate-viscosity resin (Grandio – Voco) and one low-viscosity resin (Filtek Supreme XTE – 3M ESPE). The influence of clinical handling of materials on the rate and volume of porosities has been evaluated by 3D X-ray computed tomography. Handling increases the porosity percentage and reduces the average porosity volume. Furthermore, the more flowable the material is, the more porosities it has within it. Two groups of samples were prepared in order to evaluate the influence of porosity on the mechanical and physicochemical behavior of materials: one group of samples consisted of materials simply extruded from syringes, while additional porosities were added artificially in the other samples. The polymerization stress was determined using a tensile testing machine, the absorption/solubility was measured in accordance with ISO 4049, the true tensile mechanical behavior was assessed using the VidéoTractionTM system, and the apparent compressive and flexural behaviors were studied using a compression test machine and a 3-point flexural test machine, respectively. The various organic and mineral components appear to be key elements in the physicochemical and mechanical behavior of materials. The initial porosity is also a predominant factor in terms of explaining this behavior. However, its influence is not proportional to its rate, since the addition of artificial porosities does not significantly affect the results
63

Estudo da radiopacidade de materiais odontológicos indicados como base e forramento de restaurações. Análise através da radiografia digital / Study of the radiopacity of dental materials used as base and liner of restorations. Analysis by digital radiographic

Lachowski, Karina Monteleone 03 June 2011 (has links)
A radiopacidade é um importante pré-requisito para materiais utilizados como base e forramento de restaurações, pois possibilita que o profissional identifique a presença do material e permita sua diferenciação com a estrutura dental adjacente. O objetivo desse estudo foi avaliar a radiopacidade de materiais indicados como base e forramento e comparar com a radiopacidade do esmalte, dentina e escala de alumínio. Para isso, foram analisadas 16 marcas comerciais de cimento de ionômero de vidro, 8 marcas de resina composta flow e 4 marcas de cimento de hidróxido de cálcio. Foram confeccionados três conjuntos de três corpos de prova de 4 mm de diâmetro, com espessuras de 1, 2 e 3 mm para cada cimento de ionômero de vidro e resina composta flow e de 1 mm para cada cimento de hidróxido de cálcio. Foram feitas secções transversais de coroas de três terceiros molares humanos para obtenção de espécimes de esmalte e dentina com espessura de 1, 2 e 3 mm. Como controle, uma escala de alumínio padrão com nove degraus de espessura foi utilizada. As tomadas radiográficas foram feitas com o sistema digital RVG 5000 Kodak (Kodak Company, França) e tempo de exposição de 0.32 segundos. As imagens obtidas foram trabalhadas no programa Image Tool® para obtenção dos valores médios de cinza. A análise estatística ANOVA, seguida pelo teste de Tukey (p0.05) detectou diferenças consideráveis entre os materiais da mesma categoria e entre as espessuras. Algumas marcas comerciais apresentaram radiopacidade inadequada segundo as normas ISO 4049 e 9917 (Ionomaster, Maxxion, Bioglass R, Bioglass F, Vidrion R e Vidrion F), apresentando radiopacidade inferior à da dentina, insuficiente para um correto diagnóstico. Todas as resinas compostas flow e cimentos de hidróxido de cálcio estudados apresentam radiopacidade superior a da dentina. As marcas comerciais Vitro Fil, Magic Glass, Vitrebond, Riva SC, Riva LC, Fill Magic, Opallis, Surefil Tetric N, Tetric, Hydro C, Hydcal e Liner apresentaram radiopacidade igual ou superior a do esmalte, em todas as espessuras. De um modo geral, o aumento de espessura dos materiais estudados aumenta significativamente sua radiopacidade. Conclui-se que existem materiais indicados como base e forramento de restaurações com radiopacidade inadequada para serem detectados radiograficamente. / Radiopacity is an important pre-requisite for base and liner materials, once it allows the professional to identify the presence of the material and makes its differentiation from the adjacent tooth structure possible. The aim of this study was to evaluate the radiopacity of liner and base materials and compare to the radiopacity of enamel, dentin and aluminum stepwedge. For this, 16 glass ionomer cements, 8 flowable resin composites and 4 calcium hydroxide cements were analysed. It was prepared three sets of three test specimens with 4 mm in diameter and thicknesses of 1, 2 and 3 mm for each glass ionomer cement and flowable composite and 1 mm for each calcium hydroxide cement. Cross sections were made from crowns of three third molars to obtain specimens of enamel and dentin with thickness of 1, 2 and 3 mm. As a control, a standard aluminum stepwedge with nine steps was used. Radiographs were taken with digital Kodak RVG 5000 (Kodak Company, France) and exposure time of 0.32 seconds. The images were analysed through the program Image Tool ® to obtain the mean grey values. Statistical test ANOVA followed by Tukey test (p 0.05) detected significant differences between the materials of the same category and between the thicknesses. The commercial brands Ionomaster, Maxxion, Bioglass R, Bioglass F, Vidrion R and Vidrion F, presented radiopacity lower than the radiopacity of dentin, insufficient for a correct diagnostic. All flowable resin composites and calcium hydroxide cements studied showed radiopacity superior than dentin. Vitro Fil, Magic Glass, Vitrebond, Riva SC, Riva LC, Fill Magic, Opallis, Surefil, Tetric N, Tetric, Hydro C, Hydcal and Liner showed radiopacity equal to or greater than the enamel for all thicknesses. In general, the increased thickness of the materials studied increases its radiopacity significantly. It was concluded that some materials indicated as base and liner for restorations have and inadequate radiopacity to be detected radiographically.
64

Remoção parcial de tecido cariado em lesões de cárie profundas de dentes permanentes / Partial removal of carious dentine in deep caries lesion in the permanent dentition

Jardim, Juliana Jobim January 2010 (has links)
The partial removal of carious dentine was studied by means of a literature review and a multicenter randomized controlled clinical trial. The clinical trial compared the effectiveness of an alternative treatment for deep caries lesions and the stepwise excavation in Public Health Services in Brazil. The treatment consists of partial removal of carious dentine followed by restoration in one session. A cost-effectiveness analysis the two treatments was performed. The clinical performance of amalgam and resin restorations placed in deep caries lesions with or without decayed tissue beneath them was also evaluated. Inclusion criteria: patients with ≥ nine years old, permanent molars with deep caries lesions and absence of periapical alterations, pulp sensitivity; absence of spontaneous pain; negative percussion test. The subjects were assigned to: test-group - partial removal of carious dentine (PDR) and restoration, and control-group - stepwise excavation (SW). SW consists of partial removal of carious tissue, indirect pulp capping with calcium hydroxide cement; temporary filling; cavity re-opening after 60 days, removal of the remaining soft carious tissue and filling. Clinical and radiological exams were performed annually. The outcomes were: (1) pulp sensitivity to cold test and absence of periapical alterations, assuming those parameters as indicators of pulp vitality; and (2) success of the restoration. To determine the cost-effectiveness of the treatments, the discounted cash flow method was adopted. The data were submitted to Kaplan-Meier, Log-rank test and logistic regression analysis, P<0.05. There were performed 299 treatments, 146 SW and 153 tests. There were no differences between the groups regarding baseline characteristics - age, gender and family income. The number of teeth evaluated after one and two years were 180 and 122. After one year of treatment performance, the therapy success rates were 97.9% and 74.1% of success in test and control groups respectively (P<0.000). After 2 years of follow-up, therapy survival rates of PDR and SW were 93.7% and 73.3% respectively (P=0.000). A total of 29 therapeutic failures were observed: PDR group - pulpitis (n=3), osteitis (n=1), hyperemia (n=2); SW group - pulpitis (n=15), necrosis (n=6), extraction (n=1) and restoration fracture (n=1). None of the variables studied showed a significant causal influence on the success rate, besides the type of treatment. After two year of follow-up, 181 restorations had been evaluated, 86 from the SW group and 95 from the PDR group; 65.8% were from the resin composite group and 34.2% were amalgam restorations. The survival analysis of the treatment associated with the filling material showed no difference in the rate of success (P=0.564). Regarding the treatment, both groups presented a similar rate of success: SW=95.3% and PDR=94.7% (P=0.928). Resin composite restorations presented 96.8% of success and amalgam restorations presented 94.1% of success (P=0.446). The reason for failure was fracture of filling material. The PDR provides an economy of R$ 143.37 (67.78%) per treatment compare to SW and 2.39% in the overall economy in the annual cost of the public health center. Partial caries removal could be performed as definitive treatment and the procedure of re-opening the cavity to remove the residual infected dentine is not necessary. The maintenance of carious dentine does not interfere in the maintenance of pulp vitality. The presence of decayed tissue in deep caries lesions does not seem to interfere with the survival of the restorations. Performing the partial removal of carious dentine in one session generates benefits for the public finances (direct economy), for the public health services (increase in number of treatments performed) and for the patients (comfort and time).
65

Lesões de cárie adjacentes a restaurações de resina composta em molares decíduos e a sua relação com a atividade cariosa da criança

Gomes, Márcia January 2008 (has links)
Na dentição decídua, as restaurações adesivas apresentam uma longevidade média de 2 a 3 anos, contudo, muitas vezes, essas restaurações são substituídas antes deste período médio. Dentre os motivos mais prevalentes para substituição de restaurações, a lesão de cárie secundária é o mais freqüentemente citado. Esta dissertação teve como objetivo avaliar clinicamente, através de um estudo transversal, o comportamento de lesões cariosas adjacentes a restaurações de resina composta em molares decíduos, relacionando-o com a atividade de cárie da criança e com a integridade marginal da restauração. O estudo envolveu 64 pacientes infantis, de ambos os sexos, com idades variando entre 7 a 11 anos, que possuíam restauração oclusal (n = 33) ou ocluso-proximal (n = 31) de resina composta em molares decíduos. Nos pacientes com mais de uma restauração, a randomização dos dentes foi realizada para seleção de apenas uma restauração por criança, totalizando 64 restaurações avaliadas (média de idade em meses das restaurações = 29, 31 ± 16,85, mediana 31,5 meses). Como critério de inclusão, todos os indivíduos deveriam ter sido submetidos a tratamento odontológico para atividade cariosa. Os profissionais responsáveis por tal tratamento eram orientados para seguir um protocolo de atendimento clínico a crianças cárie-ativas. Um examinador treinado e calibrado (valor de Cohen’s kappa dicotômico = 1) avaliou a atividade de doença cárie (ativo ou inativo) do paciente e a presença radiográfica de imagens radiolúcidas relacionadas às margens oclusais das restaurações. Outros dois examinadores, também treinados e calibrados, avaliaram a restauração quanto ao comportamento da lesão cariosa adjacente à restauração (ausência de lesão, lesão ativa sem cavidade, lesão ativa com cavidade, lesão inativa sem cavidade, lesão inativa com cavidade; valor de Cohen’s kappa de múltiplos critérios = 0,844) e quanto à integridade marginal (presença ou ausência; valor de Cohen’s kappa dicotômico = 1). Todos os três examinadores realizaram as avaliações de forma independente e seguindo o princípio de cegamento. As variáveis explicativas foram relacionadas ao desfecho através dos testes estatísticos Qui-quadrado e Exato de Fisher (α=5%). Mais da metade das crianças apresentava-se como cárie–ativa durante a avaliação, sendo a prevalência de lesão cariosa adjacente à restauração (LCAdj) de 40,63% (maioria lesões inativas). Não houve associação entre a presença de LCAdj e a atividade cariosa da criança (p = 0,237). Houve associação estatisticamente significativa entre ausência de LCAdj e a presença de integridade marginal (p = 0,013). Com relação ao dente restaurado, foi constatada associação estatisticamente significativa entre a presença de LCAdj e o segundo molar decíduo (p = 0,033). Verificou-se também que a presença de LCAdj ocorreu preferencialmente nas restaurações mais antigas (p = 0,044). A partir dos resultados, pôde-se concluir que mesmo em pacientes inseridos em um programa de manutenção periódica profissional há uma grande ocorrência de lesões cariosas adjacentes a restaurações adesivas, predominando lesões inativas. A presença de integridade marginal da restauração mostrou estar relacionada à ausência desse tipo de lesão, contudo ausência de integridade marginal não foi completamente relacionada à LCAdj. Embora, não tenha sido possível observar correlação entre a atividade cariosa das crianças e a presença da LCAdj, futuros ensaios clínicos são necessários para observar o comportamento desse tipo de lesão. / In the deciduous teeth the adhesive restorations last from 2 to 3 years although sometimes replacement takes place before the mean time. Among the most prevalent reasons for replacement of restorations, the secondary caries lesion is mentioned more often. The aim of this study was to evaluate clinically, through a transversal study, the behavior of adjacent caries lesion to composite resin restorations in deciduous molars, considering the relationship of the new lesion to the caries activity of the child and the marginal integrity of the restoration. Sixty four male and female pediatric patients mean age from 7 to 11years and with oclusal (n = 33) or occlusoproximal (n = 31) composite resin restoration in the deciduous molars were used. In the patients where more than one restoration fit the profile, a randomized selection was performed to assure that only one tooth was used per person, in the total 64 appraised restorations (mean of the age in month of the restorations = 29, 31 ± 16,85; median 31,5 months). As inclusion criteria, all patients must have been submitted to dental treatment for disease activity. The professional who performed such treatment was oriented to follow a clinical protocol for children with an active disease. A calibrated and trained examiner (Cohen’s kappa =1) evaluated the activity of the patient’s disease (active or non active), the presence of radiolucent images on dental occlusal surface of the restoration. Another 2 examiners, also trained and calibrated, evaluated the filling as for the behavior of the adjacent caries lesion to the restoration (absence of the lesion, non-cavitated active lesion, cavitated active lesion, non-cavitated inactive lesion, cavitated inactive lesion; Cohen’s kappa = 0,844) and marginal integrity (presence or absence; Cohen’s kappa =1). All the examiners performed the evaluation independently and following blindness principles. The variables were relation to outcome through by Chi-square and Fisher’ Exact analysis (α=5%). More than half of the patients were caries active during the evaluation period. The prevalence of adjacent caries lesion to the restoration (AdjCL) was 40.63% (most inactive lesions). There was no association among the presence of AdjCL and the caries activity of the child (p=0,237). The association of the absence of AdjCL and the presence of marginal integrity was statistically significant (p=0,013). Considering the restorated tooth, there was an association statistically significant among the presence of AdjCL and the second deciduous molar (p=0,033). Also, the presence of AdjCL occurred specially around older restorations (p=0,044). Analyzing the results, it was concluded that even patients submitted to standardized individual professional controlled treatment there is great occurrence of adjacent caries lesion to adhesive restorations, most inactive lesion. The presence of marginal integrity showed to be related to the absence of this lesion, but the absence of marginal integrity was not entirely related to AdjCL. Even though the correlation between caries activity and presence of AdjCL haven’t been observed, future clinical studies are necessary to observe the behavior of this type of lesion.
66

Remoção parcial de tecido cariado em lesões de cárie profundas de dentes permanentes / Partial removal of carious dentine in deep caries lesion in the permanent dentition

Jardim, Juliana Jobim January 2010 (has links)
The partial removal of carious dentine was studied by means of a literature review and a multicenter randomized controlled clinical trial. The clinical trial compared the effectiveness of an alternative treatment for deep caries lesions and the stepwise excavation in Public Health Services in Brazil. The treatment consists of partial removal of carious dentine followed by restoration in one session. A cost-effectiveness analysis the two treatments was performed. The clinical performance of amalgam and resin restorations placed in deep caries lesions with or without decayed tissue beneath them was also evaluated. Inclusion criteria: patients with ≥ nine years old, permanent molars with deep caries lesions and absence of periapical alterations, pulp sensitivity; absence of spontaneous pain; negative percussion test. The subjects were assigned to: test-group - partial removal of carious dentine (PDR) and restoration, and control-group - stepwise excavation (SW). SW consists of partial removal of carious tissue, indirect pulp capping with calcium hydroxide cement; temporary filling; cavity re-opening after 60 days, removal of the remaining soft carious tissue and filling. Clinical and radiological exams were performed annually. The outcomes were: (1) pulp sensitivity to cold test and absence of periapical alterations, assuming those parameters as indicators of pulp vitality; and (2) success of the restoration. To determine the cost-effectiveness of the treatments, the discounted cash flow method was adopted. The data were submitted to Kaplan-Meier, Log-rank test and logistic regression analysis, P<0.05. There were performed 299 treatments, 146 SW and 153 tests. There were no differences between the groups regarding baseline characteristics - age, gender and family income. The number of teeth evaluated after one and two years were 180 and 122. After one year of treatment performance, the therapy success rates were 97.9% and 74.1% of success in test and control groups respectively (P<0.000). After 2 years of follow-up, therapy survival rates of PDR and SW were 93.7% and 73.3% respectively (P=0.000). A total of 29 therapeutic failures were observed: PDR group - pulpitis (n=3), osteitis (n=1), hyperemia (n=2); SW group - pulpitis (n=15), necrosis (n=6), extraction (n=1) and restoration fracture (n=1). None of the variables studied showed a significant causal influence on the success rate, besides the type of treatment. After two year of follow-up, 181 restorations had been evaluated, 86 from the SW group and 95 from the PDR group; 65.8% were from the resin composite group and 34.2% were amalgam restorations. The survival analysis of the treatment associated with the filling material showed no difference in the rate of success (P=0.564). Regarding the treatment, both groups presented a similar rate of success: SW=95.3% and PDR=94.7% (P=0.928). Resin composite restorations presented 96.8% of success and amalgam restorations presented 94.1% of success (P=0.446). The reason for failure was fracture of filling material. The PDR provides an economy of R$ 143.37 (67.78%) per treatment compare to SW and 2.39% in the overall economy in the annual cost of the public health center. Partial caries removal could be performed as definitive treatment and the procedure of re-opening the cavity to remove the residual infected dentine is not necessary. The maintenance of carious dentine does not interfere in the maintenance of pulp vitality. The presence of decayed tissue in deep caries lesions does not seem to interfere with the survival of the restorations. Performing the partial removal of carious dentine in one session generates benefits for the public finances (direct economy), for the public health services (increase in number of treatments performed) and for the patients (comfort and time).
67

Lesões de cárie adjacentes a restaurações de resina composta em molares decíduos e a sua relação com a atividade cariosa da criança

Gomes, Márcia January 2008 (has links)
Na dentição decídua, as restaurações adesivas apresentam uma longevidade média de 2 a 3 anos, contudo, muitas vezes, essas restaurações são substituídas antes deste período médio. Dentre os motivos mais prevalentes para substituição de restaurações, a lesão de cárie secundária é o mais freqüentemente citado. Esta dissertação teve como objetivo avaliar clinicamente, através de um estudo transversal, o comportamento de lesões cariosas adjacentes a restaurações de resina composta em molares decíduos, relacionando-o com a atividade de cárie da criança e com a integridade marginal da restauração. O estudo envolveu 64 pacientes infantis, de ambos os sexos, com idades variando entre 7 a 11 anos, que possuíam restauração oclusal (n = 33) ou ocluso-proximal (n = 31) de resina composta em molares decíduos. Nos pacientes com mais de uma restauração, a randomização dos dentes foi realizada para seleção de apenas uma restauração por criança, totalizando 64 restaurações avaliadas (média de idade em meses das restaurações = 29, 31 ± 16,85, mediana 31,5 meses). Como critério de inclusão, todos os indivíduos deveriam ter sido submetidos a tratamento odontológico para atividade cariosa. Os profissionais responsáveis por tal tratamento eram orientados para seguir um protocolo de atendimento clínico a crianças cárie-ativas. Um examinador treinado e calibrado (valor de Cohen’s kappa dicotômico = 1) avaliou a atividade de doença cárie (ativo ou inativo) do paciente e a presença radiográfica de imagens radiolúcidas relacionadas às margens oclusais das restaurações. Outros dois examinadores, também treinados e calibrados, avaliaram a restauração quanto ao comportamento da lesão cariosa adjacente à restauração (ausência de lesão, lesão ativa sem cavidade, lesão ativa com cavidade, lesão inativa sem cavidade, lesão inativa com cavidade; valor de Cohen’s kappa de múltiplos critérios = 0,844) e quanto à integridade marginal (presença ou ausência; valor de Cohen’s kappa dicotômico = 1). Todos os três examinadores realizaram as avaliações de forma independente e seguindo o princípio de cegamento. As variáveis explicativas foram relacionadas ao desfecho através dos testes estatísticos Qui-quadrado e Exato de Fisher (α=5%). Mais da metade das crianças apresentava-se como cárie–ativa durante a avaliação, sendo a prevalência de lesão cariosa adjacente à restauração (LCAdj) de 40,63% (maioria lesões inativas). Não houve associação entre a presença de LCAdj e a atividade cariosa da criança (p = 0,237). Houve associação estatisticamente significativa entre ausência de LCAdj e a presença de integridade marginal (p = 0,013). Com relação ao dente restaurado, foi constatada associação estatisticamente significativa entre a presença de LCAdj e o segundo molar decíduo (p = 0,033). Verificou-se também que a presença de LCAdj ocorreu preferencialmente nas restaurações mais antigas (p = 0,044). A partir dos resultados, pôde-se concluir que mesmo em pacientes inseridos em um programa de manutenção periódica profissional há uma grande ocorrência de lesões cariosas adjacentes a restaurações adesivas, predominando lesões inativas. A presença de integridade marginal da restauração mostrou estar relacionada à ausência desse tipo de lesão, contudo ausência de integridade marginal não foi completamente relacionada à LCAdj. Embora, não tenha sido possível observar correlação entre a atividade cariosa das crianças e a presença da LCAdj, futuros ensaios clínicos são necessários para observar o comportamento desse tipo de lesão. / In the deciduous teeth the adhesive restorations last from 2 to 3 years although sometimes replacement takes place before the mean time. Among the most prevalent reasons for replacement of restorations, the secondary caries lesion is mentioned more often. The aim of this study was to evaluate clinically, through a transversal study, the behavior of adjacent caries lesion to composite resin restorations in deciduous molars, considering the relationship of the new lesion to the caries activity of the child and the marginal integrity of the restoration. Sixty four male and female pediatric patients mean age from 7 to 11years and with oclusal (n = 33) or occlusoproximal (n = 31) composite resin restoration in the deciduous molars were used. In the patients where more than one restoration fit the profile, a randomized selection was performed to assure that only one tooth was used per person, in the total 64 appraised restorations (mean of the age in month of the restorations = 29, 31 ± 16,85; median 31,5 months). As inclusion criteria, all patients must have been submitted to dental treatment for disease activity. The professional who performed such treatment was oriented to follow a clinical protocol for children with an active disease. A calibrated and trained examiner (Cohen’s kappa =1) evaluated the activity of the patient’s disease (active or non active), the presence of radiolucent images on dental occlusal surface of the restoration. Another 2 examiners, also trained and calibrated, evaluated the filling as for the behavior of the adjacent caries lesion to the restoration (absence of the lesion, non-cavitated active lesion, cavitated active lesion, non-cavitated inactive lesion, cavitated inactive lesion; Cohen’s kappa = 0,844) and marginal integrity (presence or absence; Cohen’s kappa =1). All the examiners performed the evaluation independently and following blindness principles. The variables were relation to outcome through by Chi-square and Fisher’ Exact analysis (α=5%). More than half of the patients were caries active during the evaluation period. The prevalence of adjacent caries lesion to the restoration (AdjCL) was 40.63% (most inactive lesions). There was no association among the presence of AdjCL and the caries activity of the child (p=0,237). The association of the absence of AdjCL and the presence of marginal integrity was statistically significant (p=0,013). Considering the restorated tooth, there was an association statistically significant among the presence of AdjCL and the second deciduous molar (p=0,033). Also, the presence of AdjCL occurred specially around older restorations (p=0,044). Analyzing the results, it was concluded that even patients submitted to standardized individual professional controlled treatment there is great occurrence of adjacent caries lesion to adhesive restorations, most inactive lesion. The presence of marginal integrity showed to be related to the absence of this lesion, but the absence of marginal integrity was not entirely related to AdjCL. Even though the correlation between caries activity and presence of AdjCL haven’t been observed, future clinical studies are necessary to observe the behavior of this type of lesion.
68

Lesões de cárie adjacentes a restaurações de resina composta em molares decíduos e a sua relação com a atividade cariosa da criança

Gomes, Márcia January 2008 (has links)
Na dentição decídua, as restaurações adesivas apresentam uma longevidade média de 2 a 3 anos, contudo, muitas vezes, essas restaurações são substituídas antes deste período médio. Dentre os motivos mais prevalentes para substituição de restaurações, a lesão de cárie secundária é o mais freqüentemente citado. Esta dissertação teve como objetivo avaliar clinicamente, através de um estudo transversal, o comportamento de lesões cariosas adjacentes a restaurações de resina composta em molares decíduos, relacionando-o com a atividade de cárie da criança e com a integridade marginal da restauração. O estudo envolveu 64 pacientes infantis, de ambos os sexos, com idades variando entre 7 a 11 anos, que possuíam restauração oclusal (n = 33) ou ocluso-proximal (n = 31) de resina composta em molares decíduos. Nos pacientes com mais de uma restauração, a randomização dos dentes foi realizada para seleção de apenas uma restauração por criança, totalizando 64 restaurações avaliadas (média de idade em meses das restaurações = 29, 31 ± 16,85, mediana 31,5 meses). Como critério de inclusão, todos os indivíduos deveriam ter sido submetidos a tratamento odontológico para atividade cariosa. Os profissionais responsáveis por tal tratamento eram orientados para seguir um protocolo de atendimento clínico a crianças cárie-ativas. Um examinador treinado e calibrado (valor de Cohen’s kappa dicotômico = 1) avaliou a atividade de doença cárie (ativo ou inativo) do paciente e a presença radiográfica de imagens radiolúcidas relacionadas às margens oclusais das restaurações. Outros dois examinadores, também treinados e calibrados, avaliaram a restauração quanto ao comportamento da lesão cariosa adjacente à restauração (ausência de lesão, lesão ativa sem cavidade, lesão ativa com cavidade, lesão inativa sem cavidade, lesão inativa com cavidade; valor de Cohen’s kappa de múltiplos critérios = 0,844) e quanto à integridade marginal (presença ou ausência; valor de Cohen’s kappa dicotômico = 1). Todos os três examinadores realizaram as avaliações de forma independente e seguindo o princípio de cegamento. As variáveis explicativas foram relacionadas ao desfecho através dos testes estatísticos Qui-quadrado e Exato de Fisher (α=5%). Mais da metade das crianças apresentava-se como cárie–ativa durante a avaliação, sendo a prevalência de lesão cariosa adjacente à restauração (LCAdj) de 40,63% (maioria lesões inativas). Não houve associação entre a presença de LCAdj e a atividade cariosa da criança (p = 0,237). Houve associação estatisticamente significativa entre ausência de LCAdj e a presença de integridade marginal (p = 0,013). Com relação ao dente restaurado, foi constatada associação estatisticamente significativa entre a presença de LCAdj e o segundo molar decíduo (p = 0,033). Verificou-se também que a presença de LCAdj ocorreu preferencialmente nas restaurações mais antigas (p = 0,044). A partir dos resultados, pôde-se concluir que mesmo em pacientes inseridos em um programa de manutenção periódica profissional há uma grande ocorrência de lesões cariosas adjacentes a restaurações adesivas, predominando lesões inativas. A presença de integridade marginal da restauração mostrou estar relacionada à ausência desse tipo de lesão, contudo ausência de integridade marginal não foi completamente relacionada à LCAdj. Embora, não tenha sido possível observar correlação entre a atividade cariosa das crianças e a presença da LCAdj, futuros ensaios clínicos são necessários para observar o comportamento desse tipo de lesão. / In the deciduous teeth the adhesive restorations last from 2 to 3 years although sometimes replacement takes place before the mean time. Among the most prevalent reasons for replacement of restorations, the secondary caries lesion is mentioned more often. The aim of this study was to evaluate clinically, through a transversal study, the behavior of adjacent caries lesion to composite resin restorations in deciduous molars, considering the relationship of the new lesion to the caries activity of the child and the marginal integrity of the restoration. Sixty four male and female pediatric patients mean age from 7 to 11years and with oclusal (n = 33) or occlusoproximal (n = 31) composite resin restoration in the deciduous molars were used. In the patients where more than one restoration fit the profile, a randomized selection was performed to assure that only one tooth was used per person, in the total 64 appraised restorations (mean of the age in month of the restorations = 29, 31 ± 16,85; median 31,5 months). As inclusion criteria, all patients must have been submitted to dental treatment for disease activity. The professional who performed such treatment was oriented to follow a clinical protocol for children with an active disease. A calibrated and trained examiner (Cohen’s kappa =1) evaluated the activity of the patient’s disease (active or non active), the presence of radiolucent images on dental occlusal surface of the restoration. Another 2 examiners, also trained and calibrated, evaluated the filling as for the behavior of the adjacent caries lesion to the restoration (absence of the lesion, non-cavitated active lesion, cavitated active lesion, non-cavitated inactive lesion, cavitated inactive lesion; Cohen’s kappa = 0,844) and marginal integrity (presence or absence; Cohen’s kappa =1). All the examiners performed the evaluation independently and following blindness principles. The variables were relation to outcome through by Chi-square and Fisher’ Exact analysis (α=5%). More than half of the patients were caries active during the evaluation period. The prevalence of adjacent caries lesion to the restoration (AdjCL) was 40.63% (most inactive lesions). There was no association among the presence of AdjCL and the caries activity of the child (p=0,237). The association of the absence of AdjCL and the presence of marginal integrity was statistically significant (p=0,013). Considering the restorated tooth, there was an association statistically significant among the presence of AdjCL and the second deciduous molar (p=0,033). Also, the presence of AdjCL occurred specially around older restorations (p=0,044). Analyzing the results, it was concluded that even patients submitted to standardized individual professional controlled treatment there is great occurrence of adjacent caries lesion to adhesive restorations, most inactive lesion. The presence of marginal integrity showed to be related to the absence of this lesion, but the absence of marginal integrity was not entirely related to AdjCL. Even though the correlation between caries activity and presence of AdjCL haven’t been observed, future clinical studies are necessary to observe the behavior of this type of lesion.
69

Efeito do retardamento da polimerização da base de cimento de ionômero de vidro modificado por resina na resistência adesiva em restaurações de resina composta / Effect of delaying photoativation of resin modified glass-ionomer cement used as a liner on the bond strength of composite resin restorations

Leslie Caroll Casas Apayco 22 April 2009 (has links)
Durante o processo inicial da reação de presa, o cimento de ionômero de vidro modificado por resina (CIVMR) apresenta baixo módulo de elasticidade, característica importante quando utilizado como base de restaurações com resina composta, por diminuir o estresse de contração de polimerização nas paredes cavitárias. O presente estudo teve como objetivo analisar a influência da técnica de polimerização de uma base CIVMR (VitrebondTM) por resina na interface dente/restauração de resina composta, através de teste de microtração e análise em microscopia confocal. Foram utilizados 30 dentes molares humanos hígidos extraídos, nos quais foram confeccionadas cavidades padronizadas em sua face oclusal (5mm de comprimento x 3mm de largura x 4,5mm profundidade). O sistema adesivo utilizado AdperTM Single Bond 2 foi marcado previamente com Rodamina B (0,16mg/ml), para possibilitar a análise em microscópio confocal. Os dentes foram divididos em 3 grupos: Grupo 1 (controle): base de CIVMR VitrebondTM + fotoativação + sistema adesivo + resina composta FiltekTM Z250; Grupo 2: base de CIVMR VitrebondTM + sistema adesivo + fotoativação por 30 segundos simultânea dos dois materiais + resina composta FiltekTM Z250; Grupo 3: base de CIVMR por resina VitrebondTM + tempo de espera de 60 segundos + fotoativação + sistema adesivo + resina composta FiltekTM Z250. Após a restauração, os dentes permaneceram em água deionizada em estufa a 37 ºC por 24 horas. Em seguida, foram seccionados com disco de diamante em fatias de aproximadamente 0,8mm no sentido vestíbulo-lingual. Uma fatia de cada dente foi separada aleatoriamente para análise da presença de fendas na interface dentina/resina composta em microscopia confocal. As demais fatias foram seccionadas para a confecção de palitos, para os testes de microtração. Os resultados de resistência de união foram submetidos à análise de variância a um critério ANOVA a 5% e teste de qui-quadrado para as variáveis de presença de fendas marginais e tipo de fratura resultante (p<0,05). Não houve diferença estatisticamente significante entre os três grupos (p=0,644) com relação à resistência adesiva e tipo de fratura, predominando a fratura do tipo adesiva para todos os grupos. Quanto à presença de fendas marginais internas, foi evidenciada sua presença nos grupos 2 e 3, sem diferença estatisticamente significante entre os três grupos testados (p=0,082). Conclui-se, portanto, que a técnica de polimerização da base de cimento de ionômero de vidro modificado por resina não influencia na resistência adesiva da interface dente/restauração de resina composta. / During the initial process of setting reaction, the resin-modified glass-ionomer cement (RMGIC) shows low modulus of elasticity, which is an important characteristic when RMGIC is used as a liner in resin composites restorations, because it decreases the polymerization shrinkage stress in cavity walls. The aim of this study was to analyze the influence of polymerization techniques of resin-modified glass-ionomer cement used as a liner on the adhesive interface dentin/resin by microtensile test and confocal microscopic analysis. Standardized occlusal cavity preparations (5mm length x 3mm wide x 4.5mm depth) were prepared in 30 human extracted molars. For the analysis at the confocal microscope, the adhesive system AdperTM Single Bond 2 was previously marked with rodhamine B (0.16mg/ml). The tooth were divided into three groups: Group 1 (control): RMGIC liner VitrebondTM + photoactivation for 30 seconds + adhesive system + resin composite Filtek TM Z250; Group 2: RMGICs liner VitrebondTM + adhesive system + simultaneous photoactivation of both materials + resin composite FiltekTM Z250; Group 3: RMGICs liner VitrebondTM+ 60 seconds delay time + photoativation for 30 seconds + adhesive system + resin composite FiltekTMZ250. Specimens were stored at 37ºC in deionized water for 24 hours. After this period, tooth was sectionated in 0.8mm slices (buco-lingual). One slice of each tooth was randomly selected for confocal microscopy for analysis of the interface resin/dentin. The other slices were sectionated in sticks (mesio-distal) for microtensile test. One-way ANOVA (p<0.05) showed no significant statistical difference among groups 1, 2 and 3 (p=0.644). Quisquare test showed no significant statistical difference of type of fracture (adhesive fracture was predominant) and presence of gap at the interface dentin/resin among groups. (p=0.082). It can be concluded, that polymerization technique of resin-modified glassionomer cement (RMGIC) did not influence bond strength and dentin/resin composite interface.
70

Efeito da base de cimento de ionômero de vidro convencional e modificado por resina na interface adesiva dente/resina composta após termociclagem / Effect of conventional and resin-modified glass ionomer cements base on tooth/composite resin adhesive interface after termocycling

Paula Costa Pinheiro Sampaio 24 April 2009 (has links)
Resinas compostas apresentam contração de polimerização e a tensão gerada durante essa polimerização compete com a força adesiva na interface dente/restauração. A técnica incremental e o uso de bases com alta resiliência e módulo de elasticidade próximo ao das estruturas dentárias são técnicas desenvolvidas para tentar diminuir a tensão originada pela contração de polimerização. O presente estudo teve como objetivo analisar a influência do uso de bases de cimento de ionômero de vidro convencional e modificado por resina na qualidade e adaptação marginal na interface dentina/resina composta, após a ciclagem térmica, usando testes de resistência adesiva e análise em microscopia confocal de varredura a laser. Foram confeccionadas cavidades na face oclusal (4,5mm x 3mm x 5mm) de 60 molares humanos extraídos divididos em 6 grupos: 1 e 4 - sistema adesivo (AdperTM Single Bond; 3M ESPE) + resina composta (Filtek Z250; 3M ESPE); 2 e 5 - base de cimento de ionômero de vidro convencional (Ketac Molar Easymix; 3M ESPE) + sistema adesivo + resina composta; e 3 e 6 - base de cimento de ionômero de vidro modificado por resina (Vitrebond; 3M ESPE) + sistema adesivo + resina composta. Os grupos 4, 5 e 6 sofreram um processo de termociclagem com dois banhos (5ºC 55ºC) durante 30 segundos em 5.000 ciclos. Após 24 horas, os dentes foram seccionados em uma máquina de cortes com disco de diamante em espessura de 0,8mm. Uma fatia de cada dente foi separada aleatoriamente para análise em Microscópio Confocal para observação e mensuração de possíveis fendas marginais internas. As demais fatias foram seccionadas para a confecção de palitos (0,8mm X 0,8mm) que foram submetidos a testes de microtração em uma máquina de ensaios universal EMIC. Os resultados de resistência adesiva foram submetidos à análise de variância a um critério (ANOVA) e ao teste t-Student (p< 0,05). A presença de fendas foi avaliada com o teste da razão de verossimilhança ou teste exato de Fisher e os valores de comprimento das fendas foram avaliados pelo teste não paramétrico de Kruskal-Wallis (p<0,05). Não foram observadas diferenças estatisticamente significantes na resistência adesiva em nenhum dos grupos sem termociclagem (G1 19,28 MPa; G2 16,29 MPa; e G3 15,95MPa) ou com termociclagem (G4 19,74 MPa; G5 16,58 MPa; e G6 16,01 MPa). A análise das medidas das fendas revelou não haver diferença estatisticamente significante entre os grupos G1 (1,4µm), G2 (2,88µm) e G3 (4,63µm) e entre os grupos G4 (4,2µm), G5 (12,5µm) e G6 (5,4µm). No entanto, a termociclagem determinou um aumento do tamanho médio das fendas no grupo com base de CIV convencional (G4 12,5µm). A análise da presença ou ausência de fendas mostrou um aumento na porcentagem do número de fendas quando os espécimes foram termociclados, para os grupos sem base e com base de CIV (G1 - 30%; G2 - 25% G3 25%; G4 - 53,33%; G5 70%; e G6 30%). Os resultados mostraram, ainda, não haver relação entre o comprimento e a formação das fendas com a resistência adesiva. Conclui-se, portanto, que o uso de base de cimento de ionômero de vidro modificado por resina mantém mais estável a qualidade da interface adesiva dentina/resina composta após envelhecimento artificial com termociclagem. / Polymerization shrinkage leads to a tension into dentin/resin composite interface that can cause marginal discoloration, poor marginal adaptation, secondary caries and post-operative sensitivity. The incremental restorative technique and the use of a resilient liner with a modulus of elasticity similar to dental structures are techniques used to decrease the shrinkage polymerization tension. The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the adhesive interface dentin/resin of occlusal restorations after thermocycling aging. Occlusal cavities were prepared sixty human extracted molars, divided into six groups: 1 and 4 with no liner; 2 and 5 glass-ionomer cement (Ketac Molar Easymix); and 3 and 6 resin-modified glass-ionomer cement (Vitrebond). Resin composite (Filtek Z250) was placed after application of adhesive system Adper Single Bond 2. Adhesive system was mixed with fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. After that, the specimens of groups 4, 5, 6 were thermocycled into 2 baths (5ºC 55ºC) of 30s each in 5.000 cycles. After this period, teeth were sectioned in 0,8mm slices. One slice of each tooth was randomly selected for analysis in Confocal Microscopy. The other ones were sectioned in sticks, which were submitted to micro-tensile test. The results of adhesive strength were analyzed by one way ANOVA and t-Student tests. Gap formation were analysed by Fisher test and the gaps size were analyzed by Kruskal-Wallis test (p<0,05). No statistical difference on adhesive resistance was showed between groups. Confocal Microscopy analysis showed gaps with a higher mean sizes for group 4 (12,5µm) and higger percentage of marginal gaps formation for the thermocycled groups (G1 - 30%; G2 - 25%; G4 - 53,33%; G5 70%). Groups 3 (25%) and 6 (30%) showed the lowest percentage of marginal gap formation. The results revealed that gap formation is not related to adhesive strength. It can be concluded, therefore, that the use of a resin-modified-glassionomer cement liner showed less gap formation on dentin/composite adhesive interface after artificial aging compared to conventional glass ionomer cement liner and restorations with no lining.

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