Influence of Different Jumping Gaps on Socket-Shield Technology: Three-Dimensional Finite Element Analysis

Socket-shield technique expands the indications for immediate implant placement and effectively maintains the contour of the labial bone. However, due to its relatively high incidence of complications, the technique has not become routine. Understanding the biomechanical characteristics among different structures in socket-shield technique has clinical significance. In this study, finite element analysis was conducted to investigate the biomechanical correlations with the exposure, migration and fracture of the root shield. Seven three-dimensional finite element models were constructed with jumping gaps of 0 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm and 3 mm, respectively. The results illustrate deep overbite loading induces unfavorable biomechanical reactions in various structures in socket-shield technique. For normal occlusion, the jumping gap that is too small leads to stress exceeding the yield strength of the root shield and comparatively large displacement in the root shield, possibly causing fracture and migration of the root shield. The jumping gap that is too large causes micro-damages to the cortical bone around the implant, potentially leading to cortical bone resorption and exposure of the root shield. Therefore, the technique should be avoided in patients with deep overbite loading, and the jumping gap of 1.5–2 mm may be a suitable choice.