Desenvolvimento e fabricação de moldes flexíveis (TPU) de baixo custo por manufatura aditiva para produção de próteses cranianas de PMMA

Abstract

Cranial defects result from trauma, tumors, infections, or decompression procedures. In most cases, a corrective cranial surgery called Cranioplasty may be required. The SUS (Unified Health System) provides the simplest Cranioplasty procedure, through manual molding during surgery. This process is time consuming, exposing the patient to risks of infection, and the aesthetic outcome will depend on the physician's ability. The present study presents the stages of the development of a solution aimed at the production of customized cranial prostheses in PMMA (Polymethyl methacrylate). This solution is based on a flexible TPU (Thermoplastic Polyurethane) mold that is cost-effectively manufactured by Additive Manufacturing (AM), whereby, by press forming, a prosthesis can be made that can be used for Cranioplasty. From the acquisition of tomographic data of patients, the reconstruction of the 3D virtual models is performed, later the prototypes of the prosthesis geometry and the fault contour are printed for preliminary verification. Next, the mold is modeled and manufactured by AM for PMMA prosthesis fabrication. In addition, the work presents a detailed analysis, from the 3D digitization of the molded prostheses and subsequent dimensional evaluation in the GOM Inspect program, the results show a dimensional deviation between 0.16 mm and 0.43 mm. At the end of the work, the main costs of the process, estimated at US$ 168, were calculated, attesting its feasibility.