Rafael Ferrone Andreiuolo

Dual-scan technique for the customization of zirconia computer-aided design/computer-aided manufacturing frameworks.

The use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of 0.3-0.6 mm around the whole tooth preparation. This may not provide uniform thickness or appropriate support for the veneering porcelain. To prevent these problems, the dual-scan technique demonstrates an alternative that allows the restorative team to customize zirconia CAD/CAM frameworks with adequate porcelain thickness and support in a simple manner.

A zircônia na Odontologia Restauradora

A necessidade de melhores propriedades mecânicas dos materiais cerâmicos levou a introducao da zirconia na Odontologia. A zirconia e um polimorfo bem conhecido que existe sob tres formas: monoclinica (m), tetragonal (t) e cubica (c). O notavel desempenho da zirconia, ja explorado em diversas aplicacoes medicas e de engenharia, deve-se principalmente a transformacao da fase tetragonal metaestavel para a fase monoclinica (T → M). O objetivo deste trabalho foi realizar uma revisao da literatura pertinente a zirconia visando um melhor entendimento de sua utilizacao na Odontologia, bem como descrever um caso clinico realizado com este material.

Mechanical behavior of non veneered three unit fixed partial dentures of alumina-zirconia Under cyclic load in wet environment

The aim of this study was to evaluate the fatigue behavior in wet environment of a ZTA three unit FPDs processed via CAD-CAM. Thirty four three unit FPDs (In-Ceram®Zirconia BZ blanks) were grinded through a CEREC In-Lab equipment followed by glass infiltration and sandblasting. Those frameworks were then submitted to different number of load cycles (400 N, 1 Hz). The FPDs that did not fractured by fatigue were submitted to a bending test in order to determine the influence of load cycling on its residual load. The non-parametric Kruskal-Wallis of those tests have shown with a 95% confidence, that there is a clear relation between the number of load cycles and its residual load. The fracture mode most frequently encountered on those FPDs was through the distal connector.

Otimização a estética em restaurações sobre implantes: revisão da literatura

Consideracoes esteticas em Implantodontia tem sido motivo de diversos estudos e publicacoes nos ultimos 15 anos, atentando-se para a existencia de diversos parâmetros que devem ser criteriosamente analisados durante a etapa de planejamento para a instalacao de implantes osseointegrados. Alguns fatores se destacam na busca do resultado estetico ideal, como o posicionamento tridimensional adequado do implante, anatomia do rebordo alveolar, fenotipo periodontal, tipo de material restaurador, perfil emergente da protese, dimensoes do espaco edentulo disponiveis e o momento de instalacao do implante.