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Introduction : The clinical survival of a dental implant is directly related to its biomechanical behavior. Since short implants present lower bone/implant contact area, their design may be more critical to stress distribution to surrounding tissues. Photoelastic analysis is a biomechanical method that uses either simple qualitative results or complex calculations for the acquisition of quantitative data. In order to simplify data acquisition, we performed a pilot study to demonstrate the investigation of biomechanics via correlation of the findings of colorimetric photoelastic analysis (stress transition areas; STAs) of design details between two types of short dental implants under axial loads. Methods Implants were embedded in a soft photoelastic resin and axially loaded with 10 and 20 N of force. Implant design features were correlated with the STAs (mm2) of the colored fringes of colorimetric photoelastic analysis. Results Under a 10 N load, the surface area of the implants was directly related to STA, whereas under a 20 N load, the surface area and thread height were inversely related to STA. Conclusion A smaller external thread height seemed to improve the biomechanical performance of the short implants investigated.
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Objective: To demonstrate a colorimetric photoelastic analysis of tension distribution around dental implants under axial loads. Material and methods: Eight different designs of implant from two manufacturers were connected to their abutments, placed into epoxy resin blocks and observed under a polariscope coupled to a universal testing machine while subjected to axial loads of 5 N. The obtained images were quantitatively analyzed by image analysis software. Results: A strong correlation was found between the surface area and the implant fringe transition area (magenta color) of most samples (r = 0.908), and a moderate correlation was found between the fringe transition area and the mean thread height of the implants (r = 0.706, or r = 0.768 using a quadratic function). Conclusion: By this biomechanical study, it was possible to demonstrate a correlation of some implant characteristics to the colored fringe areas of tension distribution, a colorimetric method that can be used in comparative studies of photoelastic analysis. Clinical significance: An accurate planning and knowledge of oral implant biomechanics is important so that a safe and long-lasting treatment can be achieved. This biomechanical study presented some correlations of the implant features and its photoelastic behavior, information that could be used by the practitioner while choosing the implant design for each clinical situation.
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Objetivo: Relatar um caso de tratamento de rânula em paciente portador do HIV/AIDS. Discussão: Paciente de 21 anos, sexo feminino, leucoderma, HIV positivo de transmissão vertical, sem hábitos deletérios, não fazia uso de drogas ilícitas, com lesão de rânula indolor, em tratamento há três meses com clindamicina, receitada pelos médicos. A paciente não está na faixa etária mais prevalente da doença, sua contagem de CD4 + estava normal e, pela possível dificuldade de cicatrização, optou-se pela micromarsupialização. Conclusão: Os cirurgiões-dentistas precisam encarar as rânulas e os mucoceles como entidades que podem surgir em pacientes infectados pelo HIV e que o tratamento deverá ser o mais conservador possível.
Objective: Report the treatment of a ranula in a patient with HIV infection. Discussion: A 21-year-old female, caucasian, with HIV infection of vertical transmission, without harmful habits and with no use of illicit drugs, presenting painless ranula lesion from three months ago being treated with clindamycin by doctors. The patient is not in the most prevalent age group, and its CD4+ counting was normal, and for the possible difficulty of healing, micro-marsupialization technique was chosen. Conclusion: Although there are few studies involving this matter, dentists must face ranulae and mucole as entities that can develop in HIV/AIDS infected patients, and treatment should be as conservative as possible.
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Humans , Female , Young Adult , Ranula/surgery , Acquired Immunodeficiency Syndrome/complications , Treatment OutcomeABSTRACT
Introduction: Fluoride plays an important role in oral health promotion and is considered important in dental caries prevention both in children and adults. Fluoride is widely used at high-risk conditions of caries, when the use of fluoride-containing mouthwashes is recommended, considering that fluoride itself reduces the risk of dental caries. Objective: To evaluate the fluoride concentration in solutions prepared at different dispensing pharmacies in the city of Curitiba - PR, Brazil. Material and methods: The analysis of fluoride concentration was preformed through Ion Chromatography method (DIONEX). Results: The results obtained through this analysis showed that all solutions presented fluoride concentration above that required in the dentist's prescription, varying between 5.48% and 24.02% more fluoride, at absolute concentration. Conclusion: This finding highlights the increasing risk of fluoride acute intoxication in cases of accidental ingestion of the solution.
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INTRODUÇÃO E OBJETIVO: O presente estudo teve como objetivo avaliar a prevalência e a severidade de fluorose dental em um grupo de escolares do município de Campo do Tenente (PR), de modo a comparar o teor médio de flúor presente na água de abastecimento público e discutir acerca dos valores efetivos para fluoretação das águas de abastecimento e da necessidade de um controle da concentração de flúor na água de que a população dispõe. MATERIAL E MÉTODOS: Foram examinadas 362 crianças, todas matriculadas em escolas públicas de ensino fundamental, procedimento feito por uma única examinadora previamente calibrada para aplicação do índice de Dean. Das crianças analisadas, 90 estavam acometidas por algum grau de fluorose; dessas 90, 40 retornaram com o termo de consentimento livre e esclarecido assinado pelos pais/responsáveis para assim participar da pesquisa. RESULTADOS: Das crianças que consentiram em fazer parte da investigação, 42,5 por cento apresentaram grau leve de fluorose e 32,5 por cento tinham grau moderado. Observou-se ainda que a média dos teores de flúor das águas de abastecimento público de 2004 foi de 1,7 ppm. CONCLUSÃO: Tais resultados demonstram que é preciso maior atenção para a situação na referida cidade, com a inclusão de heterocontrole e monitoramento constante das condições de saúde bucal da população.
INTRODUCTION AND OBJECTIVE: This study aimed to assess the prevalence and severity of dental fluorosis in a group of school children in the city of Campo do Tenente (Parana, Brazil) in order to compare the mean fluoride concentration in public water supply and discuss the effective values for fluoridation of water supply, as well as, the need of control of fluoride concentration within the water consumed by population. MATERIAL AND METHODS: Firstly, 362 children enrolled in regular public schools, at elementary level, were examined by a single researcher, previously calibrated for Dean's index application. From these, 90 children were affected by some degree of fluorosis, but only 40 returned the signed free and clarified consent form for participating in the research. RESULTS: It was found that 42.5 percent of the children presented mild fluorosis and 32.5 percent moderate fluorosis. Moreover, it was observed that the average fluoride concentration in public water supply, in 2004, was 1.7 ppm of fluoride. CONCLUSION: These results demonstrate the need of a closer supervision of the city situation, by the inclusion of fluoridation external control and constant monitoring of the oral health status of the population.