Implant Site Reaction clinical trials

Bone Particles Sizes and the Stability of Soft and Hard Tissue in Aesthetic Area

After implant restoration, the surrounding tissue, including the gingiva and alveolar bone, will inevitably reconstruct. The study found that gingival recession was easy to occur in the aesthetic area of upper anterior teeth within 1 year after implantation, which was mainly due to the absorption of labial alveolar bone. In order to avoid absorption, the thickness of the labial bone plate should not be less than 2mm, which is difficult to achieve in the anterior tooth area. Therefore, guided bone regeneration (GBR) should be performed in the implant area, which can provide more than 5mm bone increment in the vertical and horizontal positions with long-term stability, being beneficial for the maintenance of the buccal contour and the stability of the soft and hard tissues in the aesthetic area. In this study, the inorganic bone matrix extracted from bovine bone (Geistlich, Gegreen, Haiao, etc.) was used for GBR in the area with insufficient bone volume in the anterior dental implant area. The commercially available xenogeneic bone graft substitutes can be divided into large particles (1-2mm) and small particles (0.25-1mm) according to the particle size. Previous studies have found that in 6 months after implantation, the change of vertical bone height around the implant (i.e. the height from the top of alveolar ridge to the shoulder of the implant) is related to the particle size of bone powder, and large particles of bone powder may have better performance in maintaining the vertical bone height due to the following reasons: 1. Large bone particles may show better mechanical properties and better mechanical compression resistance. 2. Large bone particles may show more reasonable pore size and porosity, which may provide better environment for the growth of new bone. 3. Large bone particles may achieve more reasonable and balanced bone remodeling. However, the effect of bone particle sizes on the maintenance of soft and hard tissue around the bone graft area is still inconclusive. Thus, the purpose of this study is to compare the effects of large and small bone particle sizes on the stability of soft and hard tissues around the bone graft area within 3 years after implant restoration in the anterior tooth area.