Hydroxyapatite bone substitutes developed via replication of natural marine sponges

Abstract

The application of synthetic cancellous bone has been shown to be highly successful when its architecture mimics that of the naturally interconnected trabeculae bone it aims to replace. The following investigation demonstrates the potential use of marine sponges as precursors in the production of ceramic based tissue engineered bone scaffolds. Three species of natural sponge, Dalmata Fina (Spongia officinalis Linnaeus, Adriatic Sea), Fina Silk (Spongia zimocca, Mediterranean) and Elephant Ear (Spongia agaricina, Caribbean) were selected for replication. A high solid content (80 %wt), low viscosity (126 mPas) hydroxyapatite slurry was developed, infiltrated into each sponge species and subsequently sintered, producing a scaffold structure that replicated pore architecture and interconnectivity of the precursor sponge. The most promising of the ceramic tissue engineered bone scaffolds developed, Spongia agaricina replicas, demonstrated an overall porosity of 56-61% with 83% of the pores ranging between 100 and 500 microm (average pore size 349 microm) and an interconnectivity of 99.92%.

Biomaterial availability of magnesium substituted beta-tricalcium phosphate converted from sea urchin <i>Tripneustes gratilla</i> shell

“…Based on the pore size, these product materials could be applied in neovascularization or attracting cell adhesion and helping cell in growth. 7), 15) The cell viability of sea urchin shell was tested by using MG-63 cells. It was found that the raw powder of sea urchin shell and its hydrothermal reaction product had no negative effect on MG-63 cells.…”

“…6) At the very least a scaffold should have sufficient stability to maintain its architecture during in vitro culturing and handling throughout implantation. 7) HA and other calcium derivatives (TCP, etc.) are the most commonly used calcium phosphates, due to their calcium/phosphorus (Ca/P) ratios bring close to that of natural bone and their stability being high when in contact with physiological environment.…”

Designs from the deep: Marine organisms for bone tissue engineering

“…More recently, three sponges from the genus Spongia (S. officinalis, S. zimocca, and S. agaricina) were used as precursors, or templates, to produce porous HA scaffolds by a replication technique (Cunningham et al, 2010). Of the three sponges examined, Spongia agaricina produced the most promising replicated scaffold for bone tissue engineering as it had approximately 60% porosity with pore sizes in the range of 100-500 m and 99.9% interconnectivity (figure 1).…”

Synthesis and Characterization of Hydroxyapatite/Bioactive Glass Nanocomposite Foam and Fluorapatite/Bioactive Glass Nanocomposite Foam by Gel Casting Method as Cell Scaffold for Bone Tissue

“…The new generation (third) of bioactive glass and foams with high macroporosity, creates a framework for penetration and migration of cells through scaffold. Using these structures act as a pattern for bone growth in the three dimensions and stimulate tissue regeneration by activating genes [23][24][25]. The porous size plays a key role in design of scaffold and directly affects bone regeneration.…”

“…Size of 15-40 µm allows the growth of fibroblast, 40-100 µm is appropriate for osteoid growth, 200-350 µm allows significant growth of bone and higher than 500 µm allows quick angiogenesis. According to different studies, the optimal size for osteoconductivity is 150-600 µm [25]. The mechanical properties of scaffold should provide sufficient mechanical stability before the regeneration of new tissue in areas under load [11].…”