Vinte anos: parabéns IPCA!

art. 73º da Constituição quanto aos fins do conhecimento: “2. O Estado promove a democratização da educação e as demais condições para que a educação, realizada através da escola e de outros meios formativos, contribua para a igualdade de oportunidades, a superação das desigualdades económicas, sociais e culturais, o desenvolvimento da personalidade e do espírito de tolerância, de compreensão mútua, de solidariedade e de responsabilidade, para o progresso social e para a participação democrática na vida colectiva.” § Abstract: art. 73 of the Constitution as to the purposes of knowledge: "2. The State shall promote the democratization of education and the other conditions that enable education, both at school and elsewhere, to contribute to equality of opportunities, overcoming the economic, social and cultural inequalities, the development of personality and spirit tolerance, mutual understanding, solidarity and responsibility, to social progress and to democratic participation in public life. ".

Electromagnetic tracker feasibility in the design of a dental superstructure for edentulous patients

The success of the osseointegration concept and the Brånemark protocol is highly associated to the accuracy in the production of an implant-supported prosthesis. One of most critical steps for long-term success of these prosthesis is the accuracy obtained during the impression procedure, which is affected by factors such as the impression material, implant position, angulation and depth. This paper investigates the feasibility of 3D electromagnetic motion tracking systems as an acquisition method for modeling full-arch implant-supported prosthesis. To this extent, we propose an implant acquisition method at the patient mouth and a calibration procedure, based on a 3D electromagnetic tracker that obtains combined measurements of implant’s position and angulation, eliminating the use of any impression material. Three calibration algorithms (namely linear interpolation, higher-order polynomial and Hardy multiquadric) were tested to compensate for the electromagnetic tracker distortions introduced by the presence of nearby metals. Moreover, implants from different suppliers were also tested to study its impact on tracking accuracy. The calibration methodology and the algorithms employed proved to implement a suitable strategy for the evaluation of novel dental impression techniques. However, in the particular case of the evaluated electromagnetic tracking system, the order of magnitude of the obtained errors invalidates its use for the full-arch modeling of implant-supported prosthesis.