Objective: To investigate drill wear and consequent intraosseous temperature elevation during freehand and guided bone drilling, with attention to the effect of metal-on-metal contact during guided drilling.
Materials and methods: Osteotomies were performed on bovine ribs, with 2.0 mm diameter stainless steel drill bits of the SMART Guide System, under 3 sterilization protocols, at 800, 1200, 1500, and 2000 rpm. Sterilization was performed after every 3 drilling. Temperature was measured after every 30 drilling.
Results: The studied contributing factors had a cumulative effect, and each contributed significantly to temperature elevation. Whether guide use led to a near-necrotic (47°C) temperature increment depended largely on the applied sterilization protocol.
Conclusion: The metal sleeve is a significant contributing factor to heat generation during guided osteotomy, but its effect can be offset by keeping the other studied factors under control.