PRESS and Piezo Microsurgery (Bony Lid): A 7-Year Evolution in a Residency Program—Part 2: PRESS-Defined Site Location

Introduction: Treatment of a failing endodontic procedure via microsurgical revision presents better outcomes due, in part, to the integration of the surgical operating microscope and cone-beam computed tomography into clinical practice. However, challenges still remain with respect to the operational locations and the techniques required to address them. Posterior sites, with substantial cortical plate thicknesses and sensitive anatomy, present the dichotomy of visualization versus postsurgical regeneration of bone. The bony lid technique bridges the gap between these 2 concepts, and the application of piezosurgery renders a precise and biocompatible osseous incision. The purpose of this article was to outline through case reports the progression of piezo-guided surgery in a resident setting. Methods: The first 2 evolutions of the technique used a surgeon-defined method for site location. This third and final evolution uses a digital workflow to virtually plan the surgical procedure, integrating Standard Tessellation Language and Digital Imaging and Communication in Medicine files to create 3-dimensional guides with exacting resection locations, levels, and angles. Export of the virtually planned guide in postproduction generates the precision endodontic surgical stent to accurately define the site location and parameters of the procedure. All surgeries were executed using the piezosurgical method with increasing levels of guidance and precision throughout the evolution process. Results: Each step in the technique implementation enabled the resident to assimilate a new technique and skill set while maintaining bone architecture and minimizing volume loss postoperatively. The patient benefits were an increase in intraoperative safety and postoperative comfort. The resident benefits were accelerated regeneration timetables and increases in the confidence level of the resident and the number of scheduled posterior surgical procedures. Conclusions: The progression from crude on-site measurements to elegant and precise surgical guides enabled the access and manipulations of difficult surgical sites without compromising visibility, postoperative osseous regeneration, or patient comfort.