Introduction: Stereolithographic biomodels fabricated using rapid prototyping (RP) offer an undoubted contribution to maxillofacial surgery, especially in the study, planning and solving of complex cases. Not so long ago, these were available in Chile from abroad, however, not mimicking the bone on its physical properties, moreover with a 3D reproduction not always exact.
Objective: To develop the RP technology in our country and to obtained bone biomodels with enhanced physical properties with respect to those imported, taking as a benchmark the properties of cortical bone.
Methodology: The 3D Printing Z-Corporation ® technology was successfully transferred and implemented at the Pontificia Universidad Católica de Chile engineering laboratories. More than 100 testing specimens were 3D printed, at different printing angles, using different powder densities and concentrations of infiltration solutions under several curing conditions. The resulting physical properties were experimentally assessed. The geometric precision was measured globally and locally, using a comparative metric based on a volumetric error index between the original structure and that of its RP biomodel.
Results: Experimental values were compared with respect to cortical bone values:
- (a)
tensile fracture strength: 29%;
- (b)
fracture strength at bending: 110%;
- (c)
elastic modulus: 25%;
- (d)
ShoreD hardness: 88%;
- (e)
mass density: 95%; and
- (f)
geometric precision: 98.8%.
Conclusions: The implementation of a state of the art RP laboratory has allowed today the maxillofacial surgical community to acquire stereolithographic biomodels build in Chile, having physical characteristics near to those of the cortical bone.
Conflict of interest : None declared.