From Subtraction to Expansion: The Evolution of Osteotomy through Osseodensification

Abstract Osseodensification (OD) has emerged as a non-subtractive site preparation method that aims to preserve and compact bone tissue. This article aims to provide a comprehensive overview of the principles, biomechanical rationale, clinical applications and outcomes associated with OD in implant dentistry. It critically synthesises the existing literature to evaluate the efficacy of OD in enhancing implant primary stability and improving bone quality at the implant site. The review explores the unique design and mechanism of OD burs, which operate in a non-cutting, counter-clockwise direction to compact and autograft bone along the walls of the osteotomy. It delves into the biomechanical evidence, comparing key stability metrics such as insertion torque value and implant stability quotient between OD and conventional drilling. Histological findings related to bone-to-implant contact (BIC) and bone area fraction (BAF) are examined. Furthermore, the review details major clinical applications, including lateral ridge expansion, crestal sinus augmentation and use in immediate implant placement scenarios, addressing the technique’s advantages and limitations. The available evidence strongly suggests that OD significantly enhances primary implant stability, particularly in low-density (D3 and D4) bone. By preserving bone tissue and increasing bone density at the implant interface, OD presents a predictable and effective alternative to subtractive methods. It offers a minimally invasive approach to managing challenging clinical situations like narrow ridges and reduced vertical height below the maxillary sinus. While current findings are promising, long-term, randomised controlled trials are necessary to fully establish its impact on long-term implant survival and crestal bone stability.