RESUMO
OBJECTIVE: The aim of this in vitro study was to evaluate the changes in friction between orthodontic brackets and archwires coated with aluminum oxide (Al2O3), titanium nitride (TiN), or chromium nitride (CrN). In addition, the resistance of the coatings to intraoral conditions was evaluated. METHODS: Stainless steel canine brackets, 0.016-inch round nickel-titanium archwires, and 0.019 × 0.025-inch stainless steel archwires were coated with Al2O3, TiN, and CrN using radio frequency magnetron sputtering. The coated materials were examined using scanning electron microscopy, an X-ray diffractometer, atomic force microscopy, and surface profilometry. In addition, the samples were subjected to thermal cycling and in vitro brushing tests, and the effects of the simulated intraoral conditions on the coating structure were evaluated. RESULTS: Coating of the metal bracket as well as nickel-titanium archwire with Al2O3 reduced the coefficients of friction (CoFs) for the bracket-archwire combination (p < 0.01). When the bracket and stainless steel archwire were coated with Al2O3 and TiN, the CoFs were significantly lower (0.207 and 0.372, respectively) than that recorded when this bracket-archwire combination was left uncoated (0.552; p < 0.01). The friction, thermal, and brushing tests did not deteriorate the overall quality of the Al2O3 coatings; however, some small areas of peeling were evident for the TiN coatings, whereas comparatively larger areas of peeling were observed for the CrN coatings. CONCLUSIONS: Our findings suggest that the CoFs for metal bracket-archwire combinations used in orthodontic treatment can be decreased by coating with Al2O3 and TiN thin films.
RESUMO
PURPOSE: To assess the need and willing for education of oncology experts for the implementation of the European Educational Programme (EEP) "Learning to live with cancer", and to analyze how participants evaluated the first 3 seminars "Education of educators". MATERIALS AND METHODS: In March, April and May 2003, three 3-day seminars entitled "Education of educators" for implementing the EEP "Learning to live with cancer" were organized by a certified educator team of the Institute for Oncology and Radiology of Serbia, Belgrade. The attendees (n=70) answered a questionnaire specially constructed in order to assess their previous knowledge about the topics of the seminar, their satisfaction with the content of the seminar, their attitude towards implementation of what they learned in daily routine practice, and their willingness to continue such an education in the future. RESULTS: Education of patients and their families was not a part of daily routine practice of 79% of the attendees, and 88.6% of them thought that their patients would benefit from the implementation of the EEP. The knowledge acquired during the seminars was completely or partially new for 76% of the participants, and 96% of them thought that similar seminars should be organized on a regular basis--once a year. Readiness to participate actively in future seminars expressed 64% of the attendees, and all of them suggested topics they thought most interesting for their practice. CONCLUSION: The content of the three seminars satisfied the great majority of the attendees. Their positive attitude and willingness to implement what they have learned in their practice confirmed the need to apply the EEP in the holistic treatment of cancer patients.