Aim: The purpose of this study is to compare the marginal fit crowns manufactured using different CAD/CAM materials on 2 types finish line design.Material and Method: Tooth preparations were made by creating lines (rounded shoulder, chamfer) an acrylic mandibular second premolar model. Impressions taken each preparation polyvinylsiloxane impression material, blocks with three compositions inclu...

This paper compares two methods for object localization from contours: shape context and chamfer matching of templates. In the light of our experiments, we suggest improvements to the shape context: Shape contexts are used to find corresponding features between model and image. In real images it is shown that the shape context is highly influenced by clutter, furthermore even when the object is...

Parametric chamfer alignment (PChA) is commonly employed for aligning an observed set of points with a corresponding set of reference points. PChA estimates optimal geometric transformation parameters that minimize an objective function formulated as the sum of the squared distances from each transformed observed point to its closest reference point. A distance transform enables efficient compu...

The aim of this study was to evaluate the fracture strength of teeth with different cavosurface margin cavity preparations and restored with composite resin and different adhesive systems. Eighty premolars were randomly divided in 8 groups, as follow: G1- sound teeth; G2- MOD preparation (no restoration); G3- Adper Single Bond without bevel preparation (butt joint); G4- Adper Single Bond with b...

Various acquisition, analysis, visualization and compression approaches sample surfaces of 3D shapes in a uniform fashion, without any attempt to align the samples with sharp edges or to adapt the sampling density to the surface curvature. Consequently, triangle meshes that interpolate these samples usually chamfer sharp features and exhibit a relatively large error in their vicinity. We presen...

Building facade extraction is the primary step in the recognition process in outdoor scenes. It is also a challenging task since each building can be viewed from different angles or under different lighting conditions. In outdoor imagery, regions, such as sky, trees, pavement cause interference for a successful building facade recognition. In this paper we propose a knowledge based approach to ...

This study examined the effect of four margin designs on marginal adaptation of Captek crowns during selected processing steps. Twenty-four Captek crowns were fabricated, six each of four margin designs: shoulder (Group A), chamfer (Group B), chamfer with bevel (Group C), and shoulder with bevel (Group D). Marginal discrepancies between crowns and matching dies were measured at selected points ...

This paper proposes an approach to investigate the influencing factors of the brake pad on the disc brake squeal by integrating finite element simulations with statistical regression techniques. Complex eigenvalue analysis (CEA) has been widely used to predict unstable frequencies in brake systems models. The finite element model is correlated with experimental modal test. The ‘input-output’ re...