Influence of graft quality and marginal bone loss on implants placed in maxillary grafted sinus: a finite element study

Abstract

The purpose of this study was to investigate the biomechanical effects of graft stiffness and progression of marginal bone loss (MBL) in the bone surrounding an implant placed in a maxillary grafted sinus based on the finite element method. The simulating model of graft stiffness as well as depth of MBL was varied to simulate nine different clinical scenarios. The results showed that the high-level strain distributions in peri-implant tissue increased with the increase in MBL depth when the stiffness of the graft was less than that of the cancellous bone (less stiffness graft models). The strain energy density (SED) value showed that a slight MBL depth (1.3 mm) with medium stiffness of grafted bone can reach the optimal load sharing due to the exhibited similar values of SED in the crestal cortical, cancellous, and grafted bone. With progression of MBL and the decrease in graft quality, maximal displacement of the implant increased considerably. Our results demonstrated that the effects of the two investigated factors (progression of MBL and graft stiffness) on the biomechanical adaptation are likely to be interrelated. The results also reveal that for clinical situations with poor grafted bone quality and progression of MBL, it is critical to consider implant stability.

Sinus Floor Augmentation Using Straumann® BoneCeramic™ and Bio‐Oss® in a Split Mouth Design and Later Placement of Implants: A 5‐Year Report from a Longitudinal Study

“…In the present study, the marginal bone level decreased significantly in the BCP group after 3 years and the significant decrease sustained after 5 years of loading in contrast to the DBB group where there was no significant marginal bone decrease. It has been suggested, based on the finite element method, that load distribution and marginal bone loss around dental implants placed in augmented sinuses may be associated with the characteristics of the grafting materials . Furthermore, a stiffer graft may result in stress reduction in the residual bone .…”

“…It has been suggested, based on the finite element method, that load distribution and marginal bone loss around dental implants placed in augmented sinuses may be associated with the characteristics of the grafting materials. 56 Furthermore, a stiffer graft may result in stress reduction in the residual bone. 57 Bone formation seems to take place mainly between the BCP particles rather than on the particle surfaces in the early healing phase 15,58,59 resulting in a lower bone to particle contact compared with DBB.…”

Maxillary sinus augmentation by crestal access: a retrospective study on cavity size and outcome correlation

“…In WS, a greater area is grafted and subjected to a greater and a longer graft resorption and replacement with new bone than in NS. This particular "active" bone substratum in conjunction with the peculiarity of each patient may lead to a different distribution of loading forces at the crestal level, which may produce a different MBL around the implant neck (Inglam et al 2010). Nevertheless, further investigation will be necessary to recognize the exact process involving the MBL around implants placed in an augmented sinus and maxillary sinus size.…”

Marginal Bone Loss in Implants Placed in Grafted Maxillary Sinus

“…While the osseous support of implants in pristine maxillae is exclusively native bone, peri‐implant tissues may also contain remnant graft particles after maxillary sinus floor elevation. Finite element analyses have suggested that the load distribution and MBL around implants placed in grafted sinus cavities may be strongly conditioned by the characteristics of the grafting material . Thus, it was observed that when the grafted volume was less stiff than the native bone, functional loading increased the concomitant stress at crestal bone level, which is typically associated with MBL .…”

“…Finite element analyses have suggested that the load distribution and MBL around implants placed in grafted sinus cavities may be strongly conditioned by the characteristics of the grafting material. [31][32][33] Thus, it was observed that when the grafted volume was less stiff than the native bone, functional loading increased the concomitant stress at crestal bone level, 33 which is typically associated with MBL. 34 With regard to the biomaterial composite used in the present study, anorganic bovine bone material behaves in a similar way to autologous chin bone particles in augmented sinus areas except for a much slower resorption rate in comparison with autogenous grafts.…”