Katia Olmedo Braun

Reducing the negative effects of chemical polishing in acrylic resins by use of an additional cycle of polymerization

STATEMENT OF PROBLEM The chemical polishing of dentures and orthodontic appliances is an efficient and time-saving technique. However, the process may adversely affect the physical properties of resin. PURPOSE This study evaluated the effect of an additional polymerization cycle in a microwave or water bath on the physical properties of an autopolymerized acrylic resin submitted to chemical polishing. MATERIAL AND METHODS Control groups comprised acrylic resin specimens submitted to mechanical (group 1) and chemical (group 2) polishing. Experimental groups comprised chemically polished specimens submitted to an additional cycle of polymerization in a microwave at 450 W for 3 minutes (group 3) or in a hot water bath at 65 degrees C for 1 hour (group 4). For the residual monomer test, 10 standardized half-disc specimens (30 x 3 mm) were fabricated for each of the test groups, and daily ultraviolet spectrophotometric (206 nm) analyses were assessed for 13 days (microg/cm(2)). For transverse strength and internal Knoop hardness (KH) tests, 10 (65 x 10 x 2.5 mm) and 5 (32 x 10 x 2.5 mm) specimens were fabricated for each test group, respectively. Internal Knoop hardness (kg/mm(2)) was assessed at depths of 100, 700, and 1500 microm. Transverse strength (MPa) was measured with a 3-point bending test in a universal testing machine with a 10-kg load cell at a crosshead speed of 5 mm/min. The data were analyzed with 1-way analysis of variance, and the means were compared with Students t test and Tukey-Kramer intervals (P<.05). RESULTS At the end of the first day of the test, all groups showed significantly different residual monomer levels (P<.05). The groups in order of decreasing residual monomer were: group 2 (1315.7 +/- 225.5 microg/cm(2)), group 3 (848.2 +/- 150.4 microg/cm(2)), group 4 (295.1 +/- 81.6 microg/cm(2)), and group 1 (136.6 +/- 45.5 microg/cm(2)). After 13 days of water storage, the lowest residual monomer levels were recorded for group 1 (4.6 +/- 1.6 microg/cm(2)). There were no significant differences among group 2 (11.3 +/- 3.1 microg/cm(2)), group 3 (9.6 +/- 1.5 microg/cm(2)), and group 4 (12.3 +/- 1.7 microg/cm(2)). Group 1 demonstrated the highest transverse strength (78.1 +/- 6.1 MPa); the other groups were not significantly different from each other. All groups exhibited lower KH values at the 100-microm depth than at 700- and 1500-microm depths. At the latter depths, group 4 specimens demonstrated the highest hardness values (18.0 +/- 0.5 and 18.8 +/- 0.7 kg/mm(2), respectively). CONCLUSION Within the limitations of this study, additional polymerization with hot water reduced residual monomer content of chemically polished acrylic resins on the first day. Although additional polymerization increased the internal hardness of the material, however, it did not recover the transverse strength that was decreased by the chemical polishing.

In vitro antifungal action of different substances over microwaved-cured acrylic resins.

Objective: The presence of Candida albicans on the surfaces of denture-base acrylic resins is strongly related to the development of oral stomatitis. This study evaluated the antifungal action of different agents over microwave-cured acrylic resin without polishing specimens previously contaminated with Candida albicans. Material and Methods: Sixty specimens were immersed in BHI broth previously inoculated with the yeast and stored for 3 h at 37°C. They were divided into 5 experimental groups (n=10): G1: 2% chlorhexidine solution (10 min); G2: 0.5% sodium hypochlorite (10 min); G3: modified sodium hypochlorite (10 min); G4: effervescent agent (5 min); G5: hydrogen peroxide 10v (30 min). The specimens of the control group 1 (C1) were not disinfected. Ten additional specimens of the control group 2 (C2) were not infected with the yeast, aiming to check the asepsis during the experiment. The disinfection agents were neutralized and the acrylic resin specimens were immersed in BHI Broth for 24 h. Culture media turbidity was evaluated spectrophotometrically according to the transmittance degree, i.e. the higher the transmittance the stronger the antimicrobial action. Statistical analysis was performed (Kruskal-Wallis Test, p<0.05). Results: The results, represented by the medians, were: G1 = 40; G2 = 100; G3 = 100; G4 = 90; G5 = 100; C1 = 40; C2 = 100. Conclusions: This in vitro study suggested that sodium hypochlorite-based substances and hydrogen peroxide are more efficient disinfectants against C. albicans than 2% chlorhexidine solution and the effervescent agent.

Autopercepção da perda de dentes em idosos

The objective of this work was to analyze the perceptions of a group of elderly people regarding loss of teeth. A qualitative study was conducted that used the Discourse of the Collective Subject as a methodological technique for ordering the data. The analysis of the interviews and the construction of the Discourse of the Collective Subject disclosed information on the thoughts and values associated with the loss of teeth within this group. The main results suggest that the lack of teeth caused functional and psychological problems, but that these appeared to be offset by solving the aesthetic problem. The justifications disclosed by the collective subject for edentulism predominantly reflect the healthcare model, which focuses on surgical, restorative and rehabilitation procedures, to the detriment of preventive actions and the promotion of health. Thus, the development of initiatives in the field of education and prevention regarding oral health is essential, emphasizing actions that target paying total, overall attention to the elderly, the social dimension of the illnesses standing out, as well as the role of the State as supplier of health and quality of life for all citizens.O objetivo deste trabalho foi analisar as percepcoes de um grupo de idosos sobre a perda de dentes. Realizou-se uma pesquisa qualitativa que utilizou O Discurso do Sujeito Coletivo como tecnica metodologica para a ordenacao dos dados. A analise das entrevistas e a construcao do Discurso do Sujeito Coletivo revelaram informacoes sobre os pensamentos e valores associados a perda de dentes no grupo. Os principais resultados sugerem que a falta de dentes trouxe problemas funcionais e psicologicos, mas que parecem ser compensados pela resolucao do problema estetico. As justificativas reveladas pelo sujeito coletivo para o edentulismo refletem predominantemente o modelo de atencao a saude, em que predominam procedimentos cirurgico-restauradores e reabilitadores, em detrimento de acoes preventivas e educativas. Desta forma, torna-se imprescindivel o desenvolvimento de iniciativas no campo da educacao e prevencao em saude bucal, enfatizando acoes voltadas para a atencao integral do idoso, destacando-se a dimensao social das doencas e o papel do Estado como provedor da saude e da qualidade de vida de todos os cidadaos.

Challenges and barriers to quality oral care as perceived by caregivers in long‐stay institutions in Brazil

OBJECTIVE To describe how caregivers perceive the oral health status in the elderly they care for; the routines for oral hygiene in nursing homes; caregivers perceived barriers for quality oral care; and the caregivers competence and need for training in this area. BACKGROUND The phenomena surrounding ageing has been the subject of worldwide interest, particularly concerning issues related to institutionalised elderly, where several studies have shown the precarious oral health status of such individuals. MATERIALS AND METHODS A qualitative interview study was held in a city in southern Brazil. Study participants were 26 caregivers of elderly people, belonging to seven institutions. Statements were collected through interviews, whose results were interpreted by phenomenological analysis. RESULTS Caregivers of institutionalised elderly reveal contradictions in knowledge and practices of oral health. Although it could be expected that the perception and attitudes of caregivers of their own oral health could influence the care they offer to the elderly, barriers to the implementation of such activities appear to refer to situations outside of their responsibility, especially in the absence of time and staff. CONCLUSIONS The oral care of older people in geriatric institutions requires multidisciplinary and interinstitutional actions capable of reversing the continuing framework of neglect, requiring interventions for health promotion and disease prevention that can and should be implemented in institutions.

Resoluções do Conselho de Saúde: instrumento de controle social ou documento burocrático?

The present study has a documentary character and analyzes the resolutions registered in minutes of meetings of a Health Council, as a form to characterize the social control in health carried through for this instance. The majority of the resolutions were referred to the approval of Programs and Projects, arising from the Secretariat of Health, regarding the reform, material and equipment acquisition for units of health, the qualification of existing services or the creation of new services. The study suggests that the practical one of this council seems to be bureaucratic, without any proposal of politics of health for the council is visualized. The way the resolutions have being legalized does not characterize its guiding not even the visibility of the actions for the population in general. In the studied case, it is signaled that the mere regular functioning of this council does not guarantee that exist effective social control.

Avaliação in vitro da efetividade de polimerização da resina acrílica dental ativada através de energia de microondas, quando em contato com metal

The conventional method to process acrylic resin is a time consuming step to construct removable prosthodontics. Microwave energy could provide a solution, but there are still questions regarding this process taking place in the presence of metal. The aim of this study was, therefore, to compare residual monomer, microhardness and porosity of two acrylic resins cured by different methods in the presence of a metal framework. The conditions evaluated were: Group 1 - Acrylic resin Classico, short cycle heatcured for 3 h; Group 2 - Acron MC resin cured in microwave oven for 3 min at 500 W; Group 3 - Acrylic resin Classico cured in microwave oven for 3 min at 500 W. For each group 12 specimens measured were prepared, measuring 30 X 4 mm (diameter X thickness) and containing inside a metal framework of 28 X 8 X 0.5 mm. After curing the samples were individually imersed in 6.0 ml of deionized water. Residual monomer released in the water, which was changed daily, was measured spectrophotometrically for 12 days. The specimens were polished in order to measure microhardness at the distances of 50 to 800 mm of the metal framework. The specimens were cross-sectioned to evaluate the internal and external porosity under the naked eye and using a X100 magnification. Porosity under the naked eye was observed in all of the Group 3 samples and in 50% of those from Groups 1 and 2. Under magnification, porosity was found externally and internally in all of samples. It was concluded that microwave energy can be effectively used to polymerized removable partial denture, and that, when polymerized with microwave energy, conventional resin presents higher porosity.

Self-perception of the loss of teeth among the elderly

The objective of this work was to analyze the perceptions of a group of elderly people regarding loss of teeth. A qualitative study was conducted that used the Discourse of the Collective Subject as a methodological technique for ordering the data. The analysis of the interviews and the construction of the Discourse of the Collective Subject disclosed information on the thoughts and values associated with the loss of teeth within this group. The main results suggest that the lack of teeth caused functional and psychological problems, but that these appeared to be offset by solving the aesthetic problem. The justifications disclosed by the collective subject for edentulism predominantly reflect the healthcare model, which focuses on surgical, restorative and rehabilitation procedures, to the detriment of preventive actions and the promotion of health. Thus, the development of initiatives in the field of education and prevention regarding oral health is essential, emphasizing actions that target paying total, overall attention to the elderly, the social dimension of the illnesses standing out, as well as the role of the State as supplier of health and quality of life for all citizens.O objetivo deste trabalho foi analisar as percepcoes de um grupo de idosos sobre a perda de dentes. Realizou-se uma pesquisa qualitativa que utilizou O Discurso do Sujeito Coletivo como tecnica metodologica para a ordenacao dos dados. A analise das entrevistas e a construcao do Discurso do Sujeito Coletivo revelaram informacoes sobre os pensamentos e valores associados a perda de dentes no grupo. Os principais resultados sugerem que a falta de dentes trouxe problemas funcionais e psicologicos, mas que parecem ser compensados pela resolucao do problema estetico. As justificativas reveladas pelo sujeito coletivo para o edentulismo refletem predominantemente o modelo de atencao a saude, em que predominam procedimentos cirurgico-restauradores e reabilitadores, em detrimento de acoes preventivas e educativas. Desta forma, torna-se imprescindivel o desenvolvimento de iniciativas no campo da educacao e prevencao em saude bucal, enfatizando acoes voltadas para a atencao integral do idoso, destacando-se a dimensao social das doencas e o papel do Estado como provedor da saude e da qualidade de vida de todos os cidadaos.

Evaluation of accessory furcation canals of permanent mandibular molars using radiography and clearing

Purpose: To evaluate the presence of furcation canals of permanent mandibular teeth using radiography and a clearing technique. Methods: The sample comprised 344 extracted mandibular molars. The presence of furcation canals was assessed by a single trained observer using magnifying lens (4x) for the dental radiographs and a dental optical microscope (30x) for the cleared specimens. Scanning electron microscopy (SEM) was used to evaluate morphological differences in the pulp chamber floor. Results: Radiographs showed that 9% of the specimens had radiolucent areas, 2% had an image that suggested a canal, and 89% had no abnormal findings. Clearing techniques did not show any accessory canal. SEM images revealed dentin tubules in recently extracted teeth; the other specimens had small areas with dentin tubules. Conclusion: Radiography was not better than the clearing technique to diagnose furcation canals. The clearing technique can provide three-dimensional visualization of the internal tooth anatomy for in vitro studies.

IS SODIUM HEXAMETAPHOSPHATE EFFECTIVE IN PREVENTING METAL DAMAGE IN REMOVABLE DENTURES IMMERSED IN HYPOCHLORITE CLEANER

The aim of this study was to determine the cytotoxicity induced by orthodontic miniscrews as received from manufacturer, after exposure to fluorides, and after exposure to the oral environment. Eighty-four miniscrews from Brazilian manufacturers (SIN, INP, and NEODENT) were divided into seven groups (n=12): G1 – SIN as received from manufacturer; G2 – SIN immersed for fifteen days in NaF 0.05%; G3 – SIN exposed to oral environment; G4 – INP as received from manufacturer; G5 – INP immersed for fifteen days in NaF 0.05%; G6 – Neodent as received from manufacturer; G7 – Neodent immersed for fifteen days in NaF 0.05%. Their cytotoxicity was evaluated by direct and indirect exposure tests using the wild S. cerevisiae. Oxidative stress was also evaluated through colony color assay. The results showed non-significant reduction in cell viability on direct or indirect exposure to miniscrews. Descriptors: Orthodontic Anchorage Procedures. Orthodontic appliances. Saccharomyces cerevisiae. Mariana Marquezan, Tiago Pfaff Fernandes, Liliana Gressler May, Katia Olmedo Braun Odontologia Is sodium hexametaphosphate effective in preventing metal damage in removable dentures immersed in hypochlorite cleaner? O hexametafosfato de sódio é eficaz na prevenção de danos de metal em próteses removíveis imersas em produtos de limpeza de hipoclorito? DOI: 10.5902/2236583422561 Saúde (SANTA MARIA) Como citar este artigo: Marquezan M, Fernandes TP, May LG, Braun KO. Is sodium hexametaphosphate effective in preventing metal damage in removable dentures immersed in hypochlorite cleaner? Revista Saúde (Sta. Maria). 2018; 44(1):1-The aim of this study was to evaluate if sodium hexametaphosphate (NaPO3)n is effective in preventing surface changes in Co-Cr-Mo alloy when immersed in cleansing solutions of 0.5% sodium hypochlorite (NaOCl). Thirty samples were randomly divided in to three groups (n=10) according to immersion solution: G1- distilled water (control), G2- 0.5% NaOCl, and G3- 0.5% NaOCl solution containing (NaPO3)n. Samples were evaluated before immersion (T0), 10 minutes (T1), 20 minutes (T2), and 60 minutes after immersion (T3) through Scanning Electron Microscopy (SEM) and rugosimeter. SEM showed little surface alteration in G1, dark stains in G2 and stains suggestive of a thin white film deposition in G3. The roughness analysis showed statistical significance between G1 and G2 (P≤0.05). There was also an increase in roughness in T2 and T3 (P≤0.05). (NaPO3)n protected the alloy from the harmful effects of 0.5% NaOCl, which caused surface alteration and increased roughness.

Prática de atividades físicas estão relacionadas a motricidade fina de idosos

the weekly practice of physical activities. METHODS: 139 independent elders of both genders, aged 60 and older, who responded to a survey about their weekly practice of physical activities and then, later on were subjected to M1 tests according to EMTI, which final scores determine each individual’s M1. The elderly were categorized into two groups: 60-70 years-old and above 70 years-old. RESULTS: the female gender was predominant in the sample. Most of the elders (46.56%) showed a M1 Mean Normal, followed by Inferior levels (29.50%) and Superior levels (23.74%). About 6.5% of the elders do not practice any physical activity, 5% practice it once a week, 53% twice a week and 35.5% more than two times per week. It could be observed that those practicing physical activity at least three times a week have better score on the M1 test (Mann-Whitney Test; p = 0.039). On the other hand, the group older than 70 years had a worse performance (Mann-Whitney Test, p = 0.001). CONCLUSION: The M1 Normal Medium was the score achieved with the highest percentage in the two age groups analyzed, being the group older than 70 years the one that presented worse performance. In addition, sedentary elderly or those who report having physical activity only once a week also had the worst test results.