Additive manufacturing of PLA to mimic the thrust force of mandibular bone during drilling

Abstract

Edentulism is a condition that results in the partial or total loss of teeth. It may lead to problems during chewing and be a cause of self-isolation and low self-esteem. Edentulism can be resolved both with removable prostheses (dentures) and fixed implants, with the latter being more efficient. The installation of a fixed implant involves a real surgical operation in which the jaw/mandibular bone is drilled through a special drill. One of the main cautions the surgeon must have during the operation is not to sever the nerves during the drilling. Given the composition of the bone is different in each person, the drilling thrust force is variable and controlling its movement can sometimes be complicated. Therefore, being able to test the operation on a dummy may reduce the number of errors. Additive manufacturing with its high degree of customization and ability to produce objects with almost no geometrical limitations could provide the required features to realize the dummy. In this work, the drilling properties of samples made in PLA through Fused Filament Fabrication (FFF) were studied. The samples were designed to mimic the composition of the bone. Specifically, a thin, hard, and denser outer layer and a 25% internal filling were adopted. The samples were drilled with a dental drill properly connected to a collaborative robot.