Abstract:

The goal of this study is to generate digital bone replicas, using a handheld 3D scanner, in order to serve for morphological analysis, better conservation and restoration of various bones.

Three-dimensional digitalization of bone pieces was carried out using the non-contact technique, based on the emission of signals that scanned the surface of the original bone piece. After scanning, the noise corresponding to digital distortions manifested in small edges of the original object was eliminated. Due to difficulty in having all bones required for the teaching and practical training in human anatomy as well as deterioration of many of these bones has motivated us to use this new technology to construct bone models for students of different degrees in health sciences. Thanks to Rapid Prototyping Technologies (RPT), we have achieved digital printing of anatomical models, in three dimensions, from a real image or piece, through the process known as stereolithography. This fast manufacturing is based on the deposition of thermoplastic materials by layers, planes or sections, until obtaining the final piece, hence called additive technology.

We used the 3D scanning device, Artec Eva model, with a processing capacity of 40,000,000 triangles/1 GB RAM, allowing 3D models to be manufactured in a fast and precise way with fine texture and high-resolution models. We used Dell Latitude E5440 laptop as a workstation, and the Artec Studio 10 scanning software for data processing, which is equipped with a large battery of tools to manage the scanned 3D models. In addition, Geomagic Desining 3D software was used to process the anatomical model, which allowed us to work with polygonal meshes and point cloud alignment. This software allowed modifying the designs, to eliminate the damaged geometry, to adjust dimensions, among many other possibilities and options. The 3D printing process was carried out on a Colido X3045 3D model printer. Solid three-dimensional bone models were printed by melting PLA (PolyLactic Acid) ABS (Acrylonitrile Butadiene Styrene) filaments. Using the computer software "Repetier-Host" of the printer, the design 3D files were converted into commands to be printed. The printer heats the filament, pushes it towards the extruder to get Fused Deposition Modeling.

The generation of artificial bone materials by 3D printers makes it easier for students to study the bone morphology, with all the anatomical details. In this way, digital images have been reproduced by 3D printers, with all the morphological details, such as points of muscle insertion or other anatomical features in small bones that are not optimally visualized in real pieces. On the other hand, in the near future, these techniques will allow the design of anatomical models that would serve useful in reconstructive surgery. Therefore, in the future the studies will be focused on the creation of biomaterials that are useful for these interventions.

Keywords:

Digital bone 3D replicas, stereolithography, 3D printing, Anatomy teaching.