Biomineralization at Titanium Revealed by Correlative 4D Tomographic and Spectroscopic Methods

Abstract

At an implant biointerface, where an engineered material merges into a biological environment, complex biophysicochemical interactions occur. One typical biointerface is the bond between human bone and dental or orthopedic implants, which is based on the biomineralization of essential bone components such as hydroxyapatite, at the implant surface. However, the exact bonding mechanism between bone and implants is still unclear. The distribution of both the mineralized and organic components of bone at the interface, and their origins, requires improved characterization. Here, the first correlative characterization is reported using multiple‐length‐scale tomography and spectroscopy techniques to probe the chemical structure of the biointerface between human bone and commercial titanium dental implant down to the atomic scale in four dimensions (4D). The existence of an intervening transition zone bonding mature bone tissue is demonstrated to implant at multiple length scales, where the phase of bone mineral differs immediately adjacent to the implant and atomic‐scale osseointegration is confirmed. The correlative 4D electron energy loss spectroscopy tomography and atom probe tomography workflow established herein is transferable to other applications in materials or biological sciences.

Apatite minerals derived from collagen phosphorylation modification induce the hierarchical intrafibrillar mineralization of collagen fibers

“…Bone is structurally composed of functional cells and corresponding extracellular matrix (ECM) (X. Liu et al, ; Zhang et al, ). Bone ECM, also called bone matrix, is a biomineralized hierarchical structure consists of organic and inorganic components (Gamsjaeger et al, ; Wang et al, ; Wegst, Bai, Saiz, Tomsia, & Ritchie, ). As the major organic component of bone, type I collagen (ColI) plays an essential role in biomineralization of bone matrix, which has a typical amino acid sequence and a characteristic triple‐helix structure (Ghazanfari, Khademhosseini, & Smit, ).…”

Correlative Spectromicroscopy and Tomography for Biomedical Applications Involving Electron, Ion, and Soft X-ray Microscopies

“…There is evidence of continuous bone growth and integration with the surface of the laser-modified, commercially pure, titanium dental implant. This interfacial implant was shown to be rich in Ti oxide by EELS tomography, as shown in detail in reference [3]. Figure 2b shows the tomographic reconstruction of the series of EELS element maps on the same 80 nm needle.…”

“…Biomaterials Interfaces. We have used chemically sensitive correlative imaging by X-ray tomography (CT), TEM, STEM, ET, APT, and STXM to investigate the 4D (3D plus composition) structure of the interface between human bone and a Ti dental implant, which had been in place for 47 months [3]. Figure 2 presents results from ET, EELS tomography, and APT of a FIB-machined needle-shaped sample that is about 80 nm in diameter.…”

“…Electron microscopy and atom probe tomography were performed at the Canadian Centre for Electron Microscopy at McMaster University, a facility supported by NSERC and other governmental sources. Prof. Anders Palmquist and Dr. Furqan Ali Shah at the University of Gothenburg are gratefully acknowledged for their significant role in the implant study cited in reference [3]. Scanning transmission X-ray microscopy data were acquired with the ambient STXM at the Canadian Light Source, which is supported by Canada Foundation for Innovation, NSERC, the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council Canada, and the Canadian Institutes of Health Research.…”

“…Similarly, multiple techniques probing at different length scales are required to begin to understand the complexity of eukaryotic cells in both healthy and diseased states. Thus, correlative microscopy is an efficient way to complement and validate individual characterization techniques and to improve data analysis [3]. Figure 1 shows the relative capabilities, in terms of spatial resolution and elemental/chemical sensitivity of some microanalytical methods, including those employed in the work described in this article.…”