Fabrication of 3D Bioprinted Bi-Phasic Scaffold for Bone-Cartilage Interface Regeneration.

Treatments for osteochondral defects (OCDs) are mainly palliative and, with the increase in this pathology seen among both young and elderly people, an alternative treatment modality is sought. Many tissue-engineered strategies have been explored for regenerating the cartilage-bone interface; however, they generally fall short of being ideal. Although cell-laden hydrogel scaffolds are a common approach for bone and cartilage tissue regeneration, they usually lack homogenous cell dispersion and patient specificity.

Dual Network Composites of Poly(vinyl alcohol)-Calcium Metaphosphate/Alginate with Osteogenic Ions for Bone Tissue Engineering in Oral and Maxillofacial Surgery.

Despite considerable advances in biomaterials-based bone tissue engineering technologies, autografts remain the gold standard for rehabilitating critical-sized bone defects in the oral and maxillofacial (OMF) region. A majority of advanced synthetic bone substitutes (SBS's) have not transcended the pre-clinical stage due to inferior clinical performance and translational barriers, which include low scalability, high cost, regulatory restrictions, limited advanced facilities and human resources. The aim of this study is to develop clinically viable alternatives to address the challenges of bone tissue regeneration in the OMF region by developing 'dual network composites' (DNC's) of calcium metaphosphate (CMP)-poly(vinyl alcohol) (PVA)/alginate with osteogenic ions: calcium, zinc and strontium.

In vitro proliferation and differentiation of human mesenchymal stem cells on hydroxyapatite versus human demineralised bone matrix with and without osteogenic protein-1.

Background: Allografting is currently used in lower limb reconstruction surgery. Demineralised bone matrix (DBM) is more osteoinductive compared with allografts but lacks mechanical strength. Osteogenic protein-1 (OP-1) can improve the osteoinductivity of the allograft, however recent reports indicate significant allograft resorption when it is combined with OP-1.

In vitro and in vivo optimization of impaction allografting by demineralization and addition of rh-OP-1.

Impaction allografting is a bone tissue engineering technique currently used in lower limb reconstruction orthopedic surgery. Our hypothesis was that biological optimization can be achieved by demineralization and addition of osteogenic protein-1 (OP-1) to the allograft. The objective of our in vitro study was to evaluate human mesenchymal stem cell (MSC) proliferation (Alamar Blue assay, titrated thymidine assay, total DNA Hoechst 33258, and scanning electron microscopy) and osteogenic differentiation (alkaline phosphatase assay) in two types of impacted carrier, namely, demineralized bone matrix (DBM) and insoluble collagenous bone matrix (ICBM), with or without OP-1.

Enhancing the osteoinductive properties of hydroxyapatite by the addition of human mesenchymal stem cells, and recombinant human osteogenic protein-1 (BMP-7) in vitro.

Hydroxyapatite (HA) has been widely used as a bone graft substitute. In this study, we investigated whether the addition of osteogenic protein-1 (OP-1) further enhanced the weak osteoinductive properties of hydroxyapatite when loaded with human mesenchymal stem cells (h-MSCs). Over a 14 day period, cell proliferation in both groups was assessed qualitatively using SEM and quantitatively using alamar blue assay.

In vitro evaluation of the direct effect of estradiol on human osteoblasts (HOB) and human mesenchymal stem cells (h-MSCs).

Estrogen may increase the proliferation of osteoblasts depending upon their differentiation stage. Our objective was to test the hypothesis that estradiol could stimulate the proliferation of primary human osteoblast (HOB) cells or human mesenchymal stem cells (h-MSCs). To test this hypothesis, we investigated two synthetic estradiol preparations: (a) a commercially available one (in clinical use) whose effect was evaluated using MTT assay, trypan blue cell counts and total protein assays; (b) a novel synthetic preparation (not in clinical use) using Alamar Blue assays and scanning electron microscopy (SEM).

In vitro cellular response to titanium electrochemically coated with hydroxyapatite compared to titanium with three different levels of surface roughness.

The in vitro response of primary human osteoblast-like (HOB) cells to a novel hydroxyapatite (HA) coated titanium substrate, produced by a low temperature electrochemical method, was compared to three different titanium surfaces: as-machined, Al(2)O(3)-blasted, plasma-sprayed with titanium particles. HOB cells were cultured on different surfaces for 3, 7 and 14 days at 37 degrees C. The cell morphology was assessed using scanning electron microscopy (SEM).