An Ultrasonic Osteotomy Device Enhanced Post-osteotomy Bone Healing Beyond That With a Conventional Rotary Device in a Rat Calvarial Model

Ultrasonic osteotomy devices (UODs) have many clinical benefits; for example, they cause little damage to adjacent tissues in oral surgery. However, few reports have focused on bone healing with UODs. This study aimed to compare bone healing after osteotomy with UODs versus rotary osteotomy devices (RODs) in a rat calvarial defect model. Calvarial bone defects were made with a UOD on the right side and an ROD on the left side. Micro-CT analysis revealed that the bone volume was greater with a UOD than with an ROD at 2-3 weeks. In HE-stained sections and micro-CT images, the bone wound gap was closed earlier on the UOD side than on the ROD side. Bone thickness, the quantity of newly formed bone, and the number of osteocytes were greater on the UOD side than on the ROD side. Scanning electron microscopy (SEM) showed that UOD cuts had smoother surfaces than ROD cuts. Osteoblast-like cells harvested from bone chips cut by the UOD had greater proliferative activity than those harvested from ROD-cut bone chips. The use of a UOD may assist bone regeneration, presumably because of osteoblast activation by ultrasonic microvibration and UODs cause less damage to the bone than RODs.

Research applications and opportunities in power ultrasonics

The first applications in power ultrasonics were largely focused on ultrasonic cleaning baths, which rely on generating inertial cavitation, and the incorporation of ultrasonic excitation in manufacturing processes such as joining of plastics and metals. Since the early days of power ultrasonics there has been a rapid growth in the number of applications, and the diversified range of applications, from microwelding to ultrasonic osteotomy, has been made possible by a combination of advances in experimental techniques for characterizing low ultrasonic frequency vibrations and acoustics, and advances in computational modelling. This article highlights just some of the research in power ultrasonics that aims to exploit the benefits of low ultrasonic frequency high ultrasonic amplitude vibrations. This article reports current research and suggests future opportunities in three different application areas that have seen significant recent advances: joining and shaping of metals, surgical devices, and cavitation cells.