The Effect of Under-Drilling and Osseodensification Drilling on Low-Density Bone: A Comparative Ex Vivo Study

Abstract

The aim of this study is to identify a method that can maximize implant primary stability (IPS) and bone density under the controlled drilling conditions of the same diameter and length in low-density bones through an ex vivo study. A total of 87 dental implants were placed with standard drilling, under-drilling, and osseodensification drilling in 13 fresh porcine sternums. The Periotest value and the implant stability quotient were measured to evaluate the primary stability. The difference in the Hounsfield unit (HU) between the hole and peripheral bone up to a distance of 1 mm was measured. Osseodensification and under-drilling technique increased the IPS, compared with conventional drilling technique with statistical significance under the drilling conditions of the same diameter and length. Osseodensification technique with the counter-clockwise direction had higher HU gaps than the standard drilling and osseodensification technique with clockwise direction. Due to the effect of bone densification, the gap of HU was increased by a minimum of 43 HU and a maximum of 180 HU. Within the limitations of this ex vivo study, it was found that the osseodensification technique with counter-clockwise direction is effective to increase IPS and bone mineral density in low-density bone.