Dynamics of Biomineralization and Biodemineralization

Abstract

In order to understand the fundamental processes leading to biomineralization, this chapter focuses on the earliest events of homo/heterogeneous nucleation from an initial supersaturated solution phase and subsequent growth involving various possible precursor phases (amorphous or crystalline) to the final mineral phase by specific template and other influences. We also discuss how the combination of macroscopic constant composition and microscopic atomic force microscopy provides insights into the physical mechanisms of crystal growth and phase stability and the influences of proteins, peptides or other small molecules.Biodemineralization reactions of tooth enamel and bone may be inhibited or even suppressed when particle sizes fall into certain critical nanoscale levels. This phenomenon actually involves particle-size-dependent critical conditions of energetic control at the molecular level. Clearly, this dissolution termination is a kinetic phenomenon and cannot be attributed to reaction retardation as a result of surface modification by additives. Almost all biomineralized structures are highly hierarchical at many different length scales. At the lowest level they often consist of tiny crystals, typically tens to hundreds of nanometers. This size is not arbitrary; rather, it seems to give biominerals such as bone and tooth remarkable physical characteristics.

Bio-Templated Growth of Bone Minerals from Modified Simulated Body Fluid on Nanofibrous Decellularized Natural Tissues

“…57–60 It is reported that amorphous calcium phosphate (ACP) will be formed first at a highly supersaturated calcium phosphate solution, followed by the conversion of ACP into HAP. 61, 62 Since non-mineralized SIS membranes are amorphous, it is difficult to judge the formation of ACP at the very beginning of the mineralization by using XRD. However, according to the reported theory, 61, 62 it is likely that the HAP crystals formed on the SIS membranes were rapidly converted from ACP formed at the very beginning of the biomimetic mineralization.…”

“…61, 62 Since non-mineralized SIS membranes are amorphous, it is difficult to judge the formation of ACP at the very beginning of the mineralization by using XRD. However, according to the reported theory, 61, 62 it is likely that the HAP crystals formed on the SIS membranes were rapidly converted from ACP formed at the very beginning of the biomimetic mineralization. Previous studies 11, 12, 37 have also demonstrated that both HAP-supersaturated solution and 1.5 SBF can induce heterogeneous nucleation when the solution is in direct contact with a foreign substrate.…”

Calcium Phosphate Bioceramics: A Review of Their History, Structure, Properties, Coating Technologies and Biomedical Applications

“…In solutions, ACP is readily converted to stable crystalline phases such as OCP or apatitic products. One biomineralization strategy that has received significant attention is mineralization via transient precursor phases [135]. …”

“…Glimcher reviewed the state of affairs in 1984 and concluded that whereas there was no evidence that ACP is a mature phase in bone, the possibility that it is a precursor phase in bone formation could not be excluded [136]. The transient ACP phase may conceivably be deposited directly inside the gap regions of collagen fibrils, but it may also be delivered as extrafibrillar particles [135]. This is consistent with the observation of collagen mineralization via a transient ACP precursor phase in vitro to produce aligned intrafibrillar carbonated apatite crystals [144].…”

Amorphous calcium phosphate and its application in dentistry

“…In solutions, ACP is readily converted to stable crystalline phases such as octacalcium phosphate or apatitic products. One biomineralization strategy that has received significant attention in recent years is mineralization via transient precursor phases [16]. Transient amorphous mineral phases have been detected in biomineral systems in different phyla of the animal kingdom [17].…”