998 resultados para Unground enamel


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dental tooth bleaching is a conservative option for the treatment of tooth stains. It is based on the use of hydrogen peroxide as an active agent. Despite its effectiveness to lighten tooth colour, there is concern regarding its use due to the effects it could have over enamel surface. There is scarce evidence on the subject and contradictions exist between different authors. The aim of this study was to compare enamel surface micromorphology after bleaching teeth with different concentrations of hydrogen peroxide solutions. Method: 50 healthy bovine incisors sectioned horizontally at the cemento-enamel junction were prepared. Contents of pulp chamber and tooth surfaces were cleaned. The buccal surface of each tooth was divided vertically, assigning one half to the control group (CG) and the other randomly to: Group 1: 25 samples treated with 15% hydrogen peroxide with nitrogen doped titanium dioxide. Group 2: 25 samples treated with 35% hydrogen peroxide. Square samples (2x2 mm.) were obtained and observed by SEM (magnification of 5.000x and 10.000x). Results: All treated groups showed longitudinal depressions on the surface and increased surface roughness. Conclusions: Tooth bleaching with hydrogen peroxide produces subclinical alterations over bovine enamel surface. 15% hydrogen peroxide bleaching agent produced less micromorphology alteration over bovine enamel surface than the 35% hydrogen peroxide agent.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The demand for cosmetic dentistry, including teeth whitening, has increased in recent years. The home teeth whitening and in-office, are widely used in dental practice. The mechanism by which it works is by oxidation of the chromogenic existing tooth structure. This is an effective and minimally invasive procedure that achieves tooth lighten the color, however, may cause alterations in the enamel surface, such as a dental permeability increase. Another effect caused by this procedure is tooth sensitivity, being the most common side effect, up to 65% of individuals have had a secondary effect at least once during treatment. This sensitivity and gingival irritation caused by bleaching may vary depending on the patient and used bleaching product

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Hidden caries is a type of lesion visualized in dentin, mainly by means of bitewing radiographs, in which, clinically, the occlusal enamel appears healthy or minimally demineralized and radiographically presents progressive demineralization in dentin, which may progress and compromise the pulp-dentin complex. Although the etiology of hidden caries is unknown, many theories have been studied, including structural and anatomical defects of enamel, their specific microbiota and the use of fluoride, which is most accepted theory. Considering the clinical concern, since these lesions have a silent progression and often are not detected on routine clinical examinations, this study aims to conduct a critical discussion of the etiology, prevalence, diagnostic methods and treatment decision for lesions of hidden caries, alerting professionals about the importance of routine use of bitewing radiographs even in patients considered “cariesfree” or low risk of caries, for more effective diagnosis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Periodontal treatment of teeth with furcation lesions often have unpredictable results due to several factors that may hinder therapy or influence the progress of periodontal disease. Of these, the length of the root trunk may contribute to the early injury of the furcations or even cause complications for the application of the treatment; the opening of the roots can guide the type of treatment to be instituted and cervical enamel projections may hinder the instrumentation of the region or even act as a retention plate niche. Thus, the purpose of this study was measured using a digital caliper, root logs database 400 molar both the 1st and the 2nd and both upper and lower as well as analyze using appropriate index type projection cervical enamel and through appropriate classification the opening of the roots in order to guide the diagnosis and treatment plan. We conclude that there is variation in measures of root trunk between the faces of the teeth examined and that greater cervical enamel projection (ECP) correlates with a decrease in the length of the root trunk in the sample evaluated as the first molars have higher occurrence of roots with a degree of opening larger than the second molars.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The purpose of this study was to evaluate the 12-month clinical performance of glass ionomer restorations in teeth with MIH. First permanent molars affected by MIH (48) were restored with glass ionomer cement (GIC) and evaluated at baseline, at 6 and at 12 months, by assessing tooth enamel breakdown, GIC breakdown and caries lesion associations. The data were analyzed using the chi-square test and actuarial survival analysis. The likelihood of a restored tooth remaining unchanged at the end of 12 months was 78%. No statistically significant difference was observed in the association between increased MIH severity and caries at baseline (p > 0.05) for a 6-month period, or between increased MIH severity and previous unsatisfactory treatment at baseline (p > 0.05) for both a 6- and 12-month period. A statistically significant difference was observed in the association between increased MIH severity and extension of the restoration, involving 2 or more surfaces (p < 0.05) at both periods, and between increased MIH severity and caries at baseline (p < 0.05) at a 12-month period. Because the likelihood of maintaining the tooth structures with GIC restorations is high, invasive treatment should be postponed until the child is sufficiently mature to cooperate with the treatment, mainly of teeth affected on just one face.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Odontologia Restauradora - ICT

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Odontologia Restauradora - ICT

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Pós-graduação em Odontologia Restauradora - ICT

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The aim of this study was to analyze the anticaries potential of pit and fissure sealants containing amorphous calcium phosphate (ACP) by synchrotron microtomography. Bovine enamel blocks (4x4 mm; n=50) were selected through surface hardness (Knoop) analysis. Slabs were obtained through cross-sections taken 1 mm from the border of the enamel. Five indentations, spaced 100 mu m apart, were made 300 mu m from the border. Ten specimens were prepared for each tested material (Ultraseal XT plus TM, Aegis, Embrace, Vitremer and Experimental Sealant). The materials were randomly attached to the sectioned surfaces of the enamel blocks and fixed with sticky wax. The specimens were submitted to pH cycling. After that, the surface hardness (SH1) was determined, and the blocks were submitted to synchrotron microcomputed tomography analysis to calculate the mineral concentration (Delta g(HAp) cm(-3)) at different areas of the enamel. The comparison between the SH1 and DgHAp cm(-3) showed a correlation for all groups (r=0.840; p<0.001). The fluoride groups presented positive values of DgHAp cm(-3), indicating a mineral gain that was observed mainly in the outer part of the enamel. The ACP showed mineral loss in the outer enamel compared with fluoride groups, although it inhibited the demineralization in the deeper areas of enamel. The combination of two remineralizing agents (fluoride and ACP) was highly effective in preventing demineralization.