Bone formation following sinus grafting with autogenous bone‐derived cells and bovine bone mineral in minipigs: preliminary findings

Abstract

Bone formation in a sinus grafted with a cell-free scaffold requires the presence of local progenitor cells that differentiate into osteoblasts. The purpose of this study was to examine the effect of culture expanded autogenous bone-derived cells (ABC) with bovine bone mineral (BBM) on bone formation after single-stage sinus grafting in minipigs. Bone biopsies from the iliac crest were harvested 4 weeks prior to sinus grafting and ABC were culture expanded in vitro. The sinuses of five adult minipigs were grafted. In one sinus of each minipig the space between Schneider's membrane (SM) and the sinus wall was grafted with ABC (325,000 cells per sinus, on average) and BBM. In the other sinus, BBM alone was used. The animals were sacrificed after 12 weeks. One block of each grafted area was prepared by saw cutting and the amount of newly formed bone was analysed by micro-computed tomography (mu-CT). The addition of ABC to BBM significantly increased the amount of newly formed bone compared with BBM alone on mu-CT analysis (ABC+BBM: 29.86+/-6.45% vs. BBM: 22.51+/-7.28% (P=0.016)). Bone formation was increased near SM (ABC+BBM: 20.7+/-4.5% vs. BBM: 15.43+/-3.62% (P=0.009)) and in the middle zone of the grafting material (ABC+BBM: 31.63+/-7.74% vs. BBM: 22.5+/-7.91% (P=0.001)), but not near the local host bone (ABC+BBM: 37.23+/-8.23% vs. BBM: 28.42+/-12.54% (P=0.15)). These preliminary findings indicate that supplementation of cell-free grafting material with culture expanded ABC can stimulate bone formation in areas with low bone-forming capacity.

Influence of synthetic polyethylene glycol hydrogels on new bone formation during mandibular augmentation procedures in Goettingen minipigs

“…From there, the values decreased significantly with increasing distance from the local jawbone (ROI 6). The results are comparable to those described by Busenlechner et al [30] and Fuerst et al [31], who investigated the gradient of NBF in different osteoconductive bone substitute materials during sinus floor augmentations in a curve-based manner. After 12 weeks, the gradient of NBF differed from that after 1 month.…”

Simultaneous in vivo comparison of bone substitutes in a guided bone regeneration model

“…Follow-up studies with a reduced number of animals may then become possible. However, not all bone substitutes can be distinguished from bone by CT and high-resolution mCT is only available for small animals [8,26], suggesting that histomorphometric analysis is still the method of choice for our purpose.…”

“…Preclinical models help to determine the osteoconductive properties of bone substitutes as reported for BioOss Ò (Geistlich Biomaterials, Wolhusen, Switzerland), a deproteinized bovine bone mineral [8], Ostim Ò (Heraeus Kulzer GmbH, Hanau, Germany), an aqueous paste of synthetic nanoparticular hydroxyapatite [9], and Osteoinductal Ò (Dietz GmbH, Munich, Germany), a calcium hydroxide suspended in a formulation of carbohydrate chains, pedum and esterified vaselinum [10]. Clinical studies require biopsies to evaluate graft consolidation, e.g.…”

Incomplete bone formation after sinus augmentation: A case report on radiological findings by computerized tomography at follow-up

“…First, the graft material used in augmentation was solely DBB, which is a cell-free grafting material with osteoconductive properties [10-13]. Cells possessing osteogenic potential are rich in residual host bone and elevated sinus membrane, whereas osteogenic potential of the graft is poor [1,14]. Therefore, new bone originates from the maxillary bone and progresses towards the augmented area [15,16].…”

“…In that study, with increasing distance from the host bone, the relative portion of newly formed bone declined from 38±13.3% at a 0-1 mm distance to 6.6±7% at a 4-5 mm distance. Fuerst et al [14] and Roldan et al [15] have also described the inhomogeneous distribution of bone and biomaterials within the augmented sinus in analysis by focusing on selected regions. The addition of autogenous bone, which contains bone-derived progenitor cells and osteoblasts, to bone substitutes is thought to enhance new bone formation [14].…”