Sequential drilling and drill angulation reduce the accuracy of drill hole start location in a synthetic bone model

Abstract

The accuracy of drill hole location is critical for implant placement in orthopaedic surgery. Increasing drill bit size sequentially has been suggested as a method for improving the accuracy of drill hole start location. The aim of this study was to determine whether sequential drilling or drill angulation would alter accuracy of drill hole start location. Three specialist veterinary surgeons drilled holes in synthetic bone models either directly, or with sequentially increasing drill bit sizes. Drilling was performed at 0o, 10o and 20o to perpendicular to the bone models. Three synthetic bone models were used to mimic canine cancellous and cortical bones. Sequential drilling resulted in greater inaccuracy in drill hole location when assessing all drilling angles together. There was no influence of surgeon or synthetic bone density on drilling accuracy. The combination of drill angulation and sequential drilling increased inaccuracy in drill hole start location. We conclude that sequential drilling decreased accuracy of drill hole location in the synthetic bone model when drilling was angled. Inaccuracy associated with the drill hole start location should be taken into account when performing surgery, although the magnitude of inaccuracy is low when compared with other sources of error such as angulation.

Comparative Accuracy Assessment of Dental Surgical Robotics and Dynamic Navigation in Immediate Implant Prosthesis Restoration

“…A smaller angle between the bone wall and the implant axis leads to uneven resistance at various points during implant tip insertion, increasing the likelihood of implant slippage towards the side with less resistance, thereby affecting implant placement accuracy. This finding aligns with the conclusions reached in the study by Bishop et al (22). Secondly, the buccolingual width of the bone ridge in the anterior region is narrower than that in the posterior region, which may contribute to greater implantation deviations (23).…”

Comparing the accuracy of freehand, fluoroscopically guided and aiming device-assisted drilling in veterinary orthopaedic surgery

“…To assess accuracy of drilling, the drill exit hole location was compared to the target at point C using coordinates obtained via ImageJ V.1.51 (National Institutes of Health, Bethesda, Maryland, USA). The drill holes were outlined using the oval function tool, and the centre of hole was identiied using the centroid pixel coordinates of this oval, as previously described by Bishop et al 15 The distance in pixels was then translated to distance in millimetres by calibration using the known distance Figure 1 Underneath the surface of the synthetic bone block. Four marker points were marked in order to align images before and after drilling, and to allow the accurate measurement of drilling inaccuracy from point C (circled in red).…”

Understanding why inaccuracies happen when drilling bone

“…What concerns us as surgeons is not only that increasing angulation decreases our drilling accuracy, but what the magnitude of the error might be. In their data, Bishop and colleagues show that deviation from the expected centre can be up to 1.83 mm 6 . When placing a 4.5 mm transcondylar screw in a typical humeral condyle, a correctly positioned screw will have about 2.5 mm of bone surrounding it at the isthmus.…”

“…In a study summarised on p 383 of this issue of Vet Record , Bishop and colleagues explore the accuracy of direct and sequential drilling in synthetic bone material 6 . The position of the final drill hole was compared to the intended position when drilling perpendicular to the material, as well as drilling at angles of 10 and 20 degrees.…”