Guided bone regeneration of chronic non‐contained bone defects using a volume stable porous block TiO2 scaffold: An experimental in vivo study

Abstract

Objectives To evaluate new lateral bone formation and lateral volume augmentation by guided bone regeneration (GBR) in chronic non‐contained bone defects with the use of a non‐resorbable TiO2‐block. Materials and methods Three buccal bone defects were created in each hemimandible of eight beagle dogs and allowed to heal for 8 weeks before treatment by GBR. Each hemimandible was randomly allocated to 4‐ or 12‐week healing time after GBR, and three intervention groups were assigned by block randomization: TiO2 block: TiO2‐scaffold and a collagen membrane, DBBM particles: Deproteinized bovine bone mineral (DBBM) and a collagen membrane, Empty control: Collagen membrane only. Microcomputed tomography (microCT) was used to measure the lateral bone formation and width augmentation. Histological outcomes included descriptive analysis and histomorphometric measurements. Results MicroCT analysis demonstrated increasing new bone formation from 4 to 12 weeks of healing. The greatest width of mineralized bone was seen in the empty controls, and the largest lateral volume augmentation was observed in the TiO2 block sites. The DBBM particles demonstrated more mineralized bone in the grafted area than the TiO2 blocks, but small amounts and less than the empty control sites. Conclusion The TiO2 blocks rendered the largest lateral volume augmentation but also less new bone formation compared with the DBBM particles. The most new lateral bone formation outward from the bone defect margins was observed in the empty controls, indicating that the presence of either graft material leads to slow appositional bone growth.

Impact of simultaneous placement of implant and block bone graft substitute: an in vivo peri-implant defect model

“…The results suggest that the TiO 2 scaffolds hold the basic requirements for a bone substitute; osteoconductive, biocompatible, space-making capability and volume maintenance [ 34 ], also confirmed in previous in vivo studies [ 18 , 19 , 31 ]. However, the TiO 2 scaffolds are lacking osteoinductive properties as bone formation is seen only from the lateral borders of the grafts, originating from the parent bone.…”

“…The new bone formation within the porous structures in eleven out of twelve scaffolds may indicate sufficient mechanical stability of the scaffolds for bone healing. Fractured scaffold edges were not found as previously reported [ 31 ]. This can be explained by three-wall defects in the present study, which provide stability and shelters the scaffold from external forces in contrast to its use in lateral bone augmentation models.…”

Osteoblasts in a Perfusion Flow Bioreactor—Tissue Engineered Constructs of TiO2 Scaffolds and Cells for Improved Clinical Performance

“…TiO2 scaffolds, as used here, show promising results in various in vivo experiments [6,8,11]. However, in a recent study [12] using a chronic non-contained bone defects application, less bone formation was observed in the TiO2 groups compared to membrane alone at the final time point of 12 weeks of healing. To improve the clinical performance of bone scaffolds, various bioreactor systems are suggested, including spinner flasks, rotating wall bioreactors, and perfusion systems [21].…”

“…Although TiO 2 scaffolds favor new bone ingrowth in vivo [6,8,11], in chronic bone defects the rate of bone growth was found to be too slow [12]. Therefore, bone tissue engineering (BTE) strategies are needed for these TiO 2 scaffolds to increase clinical translation.…”

Immunohistochemical comparison of lateral bone augmentation using a synthetic TiO2 block or a xenogeneic graft in chronic alveolar defects

“…Although some clinical studies have shown predictable bone gain, 1,2 others have reported less bone formation when using a graft material compared with when using the membrane alone. [3][4][5][6] In a previous in vivo experimental study, 7 GBR with a collagen membrane alone was compared with deproteinized bovine bone mineral (DBBM) and a ceramic TiO 2 scaffold. Less bone formation was observed in the TiO 2 and DBBM groups when compared with membrane alone group at the final follow-up time point after 12 weeks of healing.…”