Fresadoras odontológicas: avaliação da qualidade de usinagem em material pmma

Abstract

This work presents a methodology to evaluate the machining quality of two similar models of dental milling machines with movement in 5 axes commercialized in Brazil: CORiTEC-250i from the company Imes-Icore and DWX-50 from the company Roland DG. In this study, PMMA discs from 3 different national manufacturers were used, registered with ANVISA, applied to CAD / CAM technology and distributed according to their thickness: 14 mm and 20 mm from the company Provi-CAD; 16 mm and 25 mm from the company Protétic and 16 mm and 25 mm from the company PrimaVita. To make this analysis feasible, two models of drawings with regular geometries were elaborated, in order to evaluate the machining quality using the 4 and 5 axes of the equipment. These drawings were conditioned in a CAM Millbox software and positioned to be machined in all PMMA disks using the reference of the cardinal points: North, East, West, South and Center. Therefore, five samples were machined for each PMMA block, producing twenty samples for machining using the 4 axes of the equipment, and another twenty samples for machining using the five axes of the equipment. That is, for each model of dental milling machine forty pieces were made. These parts were sent to a measurement laboratory accredited by the Brazilian Calibration Network, where reports were prepared informing the values earned for each dimension of each piece. With the analysis of this data, we can inform the scientific environment of the accuracy achieved by the equipment, assist the developer of dental crowns (dentist or prosthetic) in order to mitigate problems and provide accuracy in the adaptation of the dental crown with the implant, improving the well-being as well as generating data that can be compared to validate the development of national dental milling projects.