Mechanostat-Informed Strain Mapping of Osseodensification-Inspired Peri-Implant Densification Versus Conventional Drilling in Osteoporotic-like Low-Density Cancellous Bone: A 3D Static Linear Finite Element Analysis

Low-density cancellous bone results in reduced trabecular support and may increase crestal cortical strain around implants. Osseodensification (OD) compacts trabecular bone and may create a peri-osteotomy densified zone, but its strain-level effects in osteoporotic-like bone are unclear. This study evaluated whether an OD-inspired peri-implant densified trabecular zone reduces crestal cortical strain compared with conventional drilling (CD) in an osteoporotic-like model. A three-dimensional finite element model of a mandibular posterior segment with a 2.0-mm cortical shell and D4 cancellous core was constructed with a 4.3 × 11.4-mm titanium implant and a cemented monolithic zirconia crown. CD used a 4.0-mm osteotomy in D4 bone. The OD model used the same osteotomy plus a concentric peri-implant densified shell with radial density gradation from D1 to D3. The implant-bone interface was defined as bonded. Static 100 N axial and 45° oblique loads were applied. Outcomes were ε_eq, ε_max, and ε_min, summarized as mean top-10 nodal values. OD reduced crestal cortical strains under both loads. Under axial loading, ε_eq, ε_max, and |ε_min| decreased by 17.7%, 19.0%, and 24.1%, respectively. Under oblique loading, the corresponding reductions were 9.8%, 8.0%, and 8.9%. Oblique loading produced higher cortical strains than axial loading in both models. OD-inspired peri-implant densification reduced crestal cortical strain in this osteoporotic-like model, whereas oblique loading remained the main driver of elevated strain. These findings support occlusal/prosthetic strategies that minimize oblique forces and warrant experimental and clinical validation.