Estudo da viabilidade do processo de reciclagem do material descartado do sistema Zirkonzanh® de produção de próteses dentárias

At present, the material of choice for performing aesthetic dental prosthetic work is in the ceramic. Among them, the ceramic base of stabilized zirconia with 3% yttria (3Y - TZP) stand out for having excellent physical and mechanical properties. During the machining of blocks of zirconia in the laboratory to prepare the various types of prostheses, much of the material is given off in the form of powder, which is subsequently discarded. The waste of this material results in financial loss, reflecting higher final cost treatment for patients, as well as damage to the environment, thanks to the processes involved in the manufacture and disposal of the ceramic. This research, pioneered the recycling of zirconium oxide powder obtained during milling of dental crowns and bridges, we highlight the social and environmental aspects and aims to establish a protocol for the reuse of waste (powder of zirconia Zirkonzahn® system) discarded to obtain a new block of compacted zirconia to maintain the same mechanical and microstructural properties of commercial high-cost imported material. To compare with the commercial material, samples were uniaxially (20 MPa) and isostatically (100 MPa), and its mechanical and microstructural characterization was performed through tests of density, porosity, dilatometry, X-ray diffraction (XRD), hardness, fracture toughness, resistance to fracture electron microscopy (SEM) and analysis of grain size. The results observed in the samples were isostatically pressed similiares those obtained with samples from the commercial material demonstrating the viability of the process

Efetividade do uso tópico de fluoreto e da escovação no controle de cáries produzidas "in vivo"

The objective of this clinical study was to evaluate the effectiveness of the toothbrushing with and without fluoride and the daily fluoride rinse (NaF 0.05%) on produced white spot, in vivo. This was a clinical study, controlled, randomized and triple blind. Thirty patients were selected for orthodontics reasons from Orthodontics Specialization Course at the Brazilian Dental Association - Section of Rio Grande do Norte. In this study it was used 4 bicuspid upper and lower. They had orthodontic reason for extractions, in 35 days, at least. The sample had one hundred and twenty teeth that received orthodontic bands. The bands were fixed with polycarboxylate cement, and there was a space standardized between bands and one surface of teeth. The four bicuspid of each patients were randomized and nominated as A, B, C and D. These nominations determinated the sequence of the extractions and what was done in each tooth. All the patients had been submitted to the toothbrushing with or without fluoride for 35 days. After this period, the A tooth of each patient was extracted to serve as control. The others teeth (B, C and D) were extracted one by each week. The entire sample was analyzed through the clinical examination and by laser fluorescence (DIAGNOdent®) in three different times: before orthodontic bands, 28 days after fixed and then removed the bands and, the last one, 07 days after one of the three treatments (toothbrushing with or without fluoride, tooth paste with fluoride and mouth rinse with fluoride). At the beginning all groups (A, B, C and D) had the same conditions, no significant difference was found. The same situation was found in a clinical examination. The results of the DIAGNOdent® for the groups that used tooth paste without fluoride, with fluoride and mouth rinse with fluoride, after 28 days, there was no significant difference. Clinically, the white spot was formed in all teeth after 28 days. When it was compared the three treated groups, the group without fluoride in tooth paste had worst result than the others groups. But there was no significant association between the number of active and inactive white spots and the type of treatment that the teeth had received. The demineralization of the enamel surface, under the orthodontic bands, it happened in a few weeks. The exposition of the white spots in oral environmental resulted in an improvement, but it was not enough to return to the values from the base line, either for the toothbrushing and/or the use of fluorite mouth rinse. Mouth rinse and toothpaste with fluoride have showed to reduce the incidence of demineralization in the enamel, but none seems to be superior to another one in an in vivo study

Estudo psicossocial das perdas dentárias na terceira idade

The present study seeks to understand tooth loss by investigating the social representations in the daily life of elderly individuals, thus characterizing itself as a comparative and analytic research. It is known that tooth loss is a common occurrence in elderly individuals, interfering at the psychosocial and biological levels, through its functional, esthetical and social implications. The area of oral health in Brazil is lacking studies on this topic, especially with respect to the psychosocial aspects of the elderly. The Theory of Social Representations and the Central Nucleus Theory were selected for theoretical-methodological support. The Free Association of Words Test was used, whose inducing stimulus were the words tooth loss , in which each subject was asked to associate 3 words, to respond to a questionnaire related to socio-economic conditions and containing an investigation of tooth loss, access to odontological services and the need for dental treatment, and to undergo a focus group interview. The study sample consisted of 120 individuals 60 years of age or over, resident in Natal, RN, Brazil and participants of the Live Together to Live Better group of the Basic Health Unit of Felipe Camarão Residential District and Unati (Open University of the Elderly); an interview was performed with 36 subjects. Data analysis was performed by Evoc 2000, SPSS/99, Graph Pad and Alceste softwares. The results demonstrate that the central nucleus of the social representations of tooth loss for the Live Together group emerged from the difficulty in eating categories, showing a relation between physiologic necessity, desire and pleasure from eating, not to mention the pain that resulted from justifying the tooth loss. Besides the central discourses, the following peripheral elements were gathered: difficulty in adapting to the prosthesis, treatment and difficulty in speaking. All of these categories, except the last, also comprised the class themes of the group interview. For the Unati group the central nucleus emerged from the socio-economic difficulties categories, demonstrating a narrow relation between poverty, access to health and education and esthetics, confirming in the discourse of common sense, the association between tooth loss and aging. At the margin of the central discourses was collected the peripheral element difficulty in adapting to the prosthesis, found both in the Live Together and Unati groups, which expresses the resistance of the subject to this new situation and the failure of the rehabilitation treatment in the sense of reviving the memory of their natural teeth. All of these categories also constitute the class themes of the of the group interview. Thus, through the study of the social representations, we can reveal a reality in the perspective of the social subjects, contemplating the multiple facets of the social-cultural reality experienced by these individuals

A produção das perdas dentárias: narrativas de usuários do SUS

For a complete comprehension of the effect of tooth loss is necessary to listen to the patients that have it. This study, of qualitative approach, investigate, in the dental history of users of SUS, listening to his/her experiences with the services of dental care, the reason that lead his/her to dental lost and the repercussion of this in his/her life. The collect of data was made by narrative interview, obeying to a pre-defined schema. The subjects interviewed were six (three of urban zone and three of rural zone), all of them were users of Family Health Units. The criterions of inclusion were the followings: the presence of tooth lost (total lost in both dental arch or in one of them, or partial lost in at least six elements in one of the arches); age between 25 and 59; male or female; to live in municipal district of São Tomé/RN or Natal/RN. Based on previous interviews was elaborated the odontological history of each patient. Such narratives, systemized in odontological history, were analyzed taking as base the studies of Souza71 and the proposal of Schutze, suggested for Jovchelovitch, Bauer34. The results show that toothache was the main reason for the search of odontological care. The patients confront the ache with home-made medicaments, allopathic ones, and searching for dental care. The searching for exodontics was stimulated for geographic access difficulties or for repressed demand, which as a result produced the aggravation of the lesions and the discredit in restoration s treatment. The self-care practice of tooth-brush with juá or toothpaste and the controlled ingestion of sugar was not sufficient to avoid dental lost. Guilty sentiments were identified in relation with lack of care with teeth. The acceptance of dental lost as a natural factor is an important motivation in lack of pain and in the belief that it was a simple part of life in old age. Life with dental prosthesis makes clear the difference between which was natural and which was unnatural, and difficulties with the prosthesis appeared. The limitation of the prosthesis in its functional aspect can be compensated by esthetic restitution, making possible smiling expression. Starting with this study and considering the high number of dental lost, mainly in low-rent population, which live with toothless limitations or bad-quality prosthesis which do not rehabilitate adequately, we suggested the realization of qualitative researches which include, also, another actors in heath care services such as professionals and administrators

Estudo da viabilidade do processo de reciclagem do material descartado do sistema Zirkonzanh® de produção de próteses dentárias

At present, the material of choice for performing aesthetic dental prosthetic work is in the ceramic. Among them, the ceramic base of stabilized zirconia with 3% yttria (3Y - TZP) stand out for having excellent physical and mechanical properties. During the machining of blocks of zirconia in the laboratory to prepare the various types of prostheses, much of the material is given off in the form of powder, which is subsequently discarded. The waste of this material results in financial loss, reflecting higher final cost treatment for patients, as well as damage to the environment, thanks to the processes involved in the manufacture and disposal of the ceramic. This research, pioneered the recycling of zirconium oxide powder obtained during milling of dental crowns and bridges, we highlight the social and environmental aspects and aims to establish a protocol for the reuse of waste (powder of zirconia Zirkonzahn® system) discarded to obtain a new block of compacted zirconia to maintain the same mechanical and microstructural properties of commercial high-cost imported material. To compare with the commercial material, samples were uniaxially (20 MPa) and isostatically (100 MPa), and its mechanical and microstructural characterization was performed through tests of density, porosity, dilatometry, X-ray diffraction (XRD), hardness, fracture toughness, resistance to fracture electron microscopy (SEM) and analysis of grain size. The results observed in the samples were isostatically pressed similiares those obtained with samples from the commercial material demonstrating the viability of the process