To induce the cascade of bone differentiation, the soluble osteogenic signals of the TGF-β superfamily must be reconstituted with an insoluble signal or substratum that triggers the bone differentiation cascade. Insoluble biomimetic matrices will have optimal surface characteristics and geometric configurations that are of critical importance for the induction of bone formation [2, 10–12].
Self-induced bone tissue induction and regeneration has been achieved via the deployment of molecular signals expressed and embedded by site specific modifications within bioactive biomimetic matrices endowed with the striking prerogative of inducing de novo bone formation even in the absence of exogenously applied osteogenic proteins of the TFG-β superfamily [2, 10–12, 40, 47].
In collaboration with the Council for Scientific and Industrial Research (CSIR, Pretoria) Materials Science and Technology, we have constructed sintered biomimetic biomatrices of highly crystalline hydroxypatite that mimics the super-smart functionality of living tissue, thereby highly crystalline porous hydroxypatites when implanted in extraskeletal heterotopic sites of the primate Papio ursinus induce the de novo initiation of bone within the smart concavities assembled within the porous spaces of the biomimetic matrices (Figs. 4 and 5) [10, 11, 40, 46, 47].
Our research in the past several years has been focused to add functionality to smart biomimetic matrices for bone repair and regeneration i.e. geometric cues initiating de novo bone formation [40, 46, 47]. The specific geometry of the substratum i.e. concavities of specific dimensions, is conducive and inducive to the generation of a micro-environ-ment that initiate the cascade of bone differentiation deploying site specific surface modifications imprinted during the synthesis of the smart biomimetic matrices (Figs. 4 and 5).
The idea that synthetic biomimetic matrices do mimic the super-smart functionality of living tissue has a futuristic appeal for the construction of smart self-inducing biomimetic matrices for tissue engineering of bone. The assembly of a series of repetitive concavities of specific dimensions within the porous biomimetic matrices adds selected functionalities or super-smart functionalities to the sintered biomimetic matrices when implanted in extraskeletal heterotopic and orthotopic sites of the primate Papio ursinus [40, 47].
By carving and sculpting a series of repetitive concavities into solid and porous biomimetic matrices of highly crystalline hydroxyapatite, we did perform the embedding of smart biological functions within intelligent scaffolds for tissue engineering of bone i.e. embedding biological signals into biomaterials designed with super-smart biomimetic functionalities [40, 46, 47].