Microscopic analysis of surgical drill plastic deformation available in implantology

Objectives: The purpose of this study was to evaluate the wear of 03 different brands of drills(nobel biocare,ankylos Dentsply and Conexão) at scanning eletron microscope(SEM). Methods: Twelve 02mm drills underwent 30 sucessive osteotomies in bovine bone rib. All drill composition was made of stainless steel alloy. They were analysed at SEM( 35X and 50X) starting baseline, 10, 20 and 30 perforation interval. Results: Neither plastic deformation was exhibited at the cutting edge nor drill fracture occurred. The conexão drills exhibited at baseline a curling aspect at the cutting edge. SEM before and after cutting revealed 03 basic patterns of wear. Conexão showed a varying degree of blunting and curling wear of the cutting edges. Nobel showed only abrasive wear and ankyloss presented no deformation of drills, although it demand higher pressure when at the osteotomies and higher temperature generated. There were no correlation between drill wear and temperature increase. Conclusions: The Ankylos and Nobel drills don't showed a significant deformation and the Conexão drills have leaved a many of fragments of metal on the bone perforation.