Biomimetic coatings for bone tissue engineering of critical-sized defects

Abstract

The repair of critical-sized bone defects is still challenging in the fields of implantology, maxillofacial surgery and orthopaedics. Current therapies such as autografts and allografts are associated with various limitations. Cytokine-based bone tissue engineering has been attracting increasing attention. Bone-inducing agents have been locally injected to stimulate the native bone-formation activity, but without much success. The reason is that these drugs must be delivered slowly and at a low concentration to be effective. This then mimics the natural method of cytokine release. For this purpose, a suitable vehicle was developed, the so-called biomimetic coating, which can be deposited on metal implants as well as on biomaterials. Materials that are currently used to fill bony defects cannot by themselves trigger bone formation. Therefore, biological functionalization of such materials by the biomimetic method resulted in a novel biomimetic coating onto different biomaterials. Bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic coating can be a solution for a large bone defect repair in the fields of dental implantology, maxillofacial surgery and orthopaedics. Here, we review the performance of the biomimetic coating both in vitro and in vivo.

Physical and biological characteristics of nanohydroxyapatite and bioactive glasses used for bone tissue engineering

“…The repair rate of a bone defect is dependent on the wound size [5]. When the defect size is greater than the healing capacity of osteogenic tissues, the fibrous connective tissue regenerates faster than bone tissue and becomes dominant in the bone defect [6]. Being a native component of bone, n-HA has an ability to promote mineralization and is a common choice as a bone graft substitute and bone filler material [7].…”

Clinical Translation in Tissue Engineering—The Surgeon’s View

“…Additional growth factors, which are gradually released, are supposed to stimulate the host to incorporate [86] the scaffold and eventually replace it by bone regeneration [87,88].…”

Gelatin-Modified Biomimetic Apatite Coatings

“…The biomimetic approach involves the use of slightly supersaturated solutions at pH and temperature values similar to those characteristic of the biological fluids [4]. Starting from the very first formulation of Simulated Body Fluid (SBF) [5], which mimics the ionic composition of blood plasma, a number of different solutions have been proposed [4,[6][7][8]. The main advantages of the biomimetic method include low cost, deposition of an apatitic phase similar to the poor crystalline carbonated apatite of bone, possible application to complexshaped and porous materials, possible co-precipitation of ions, drugs, macromolecules and biological molecules together with the calcium phosphate [9][10][11][12][13].…”