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Nondestructive three-dimensional (3D) micro-computed tomography (CT) image analysis used in orthopedic research needs to be accompanied by adequate tools for the numerical assessment of experimental systems. Such quantitative tools should be user-friendly and intuitive, not too complex for the orthopedic researcher to implement, as well as accurate and repeatable in order to be suitable for laboratory application. Here, two experimental systems are examined and straightforward micro-CT analysis methods are described, allowing the experimental outcomes to be accurately quantified in a flexible and multidimensional manner. These systems include the study of osteointegration around a metal implant in bone, and the study of porosity of a biocompatible scaffold matrix for tissue engineering (specifically, the study of scaffolds for permeability to cellular ingrowth) Both studies involve a number of standard image analysis techniques applied in a 3D manner, such as erosion and dilation (applied flexibly to both the image and the region of interest), distance transforms, and novel techniques like “shrink wrap”. Applied in combination in an easily programmable “task list” (otherwise known as “scripting”), these functions provide a powerful and versatile range of 3D structural analyses.

Implants (hemitrochlea) were prepared from nacre (mother of pearl) and implanted in the knees of sheep. Cartilage formed at the endoarticular surfaces of the implant, and new endochondral bone was also formed at the interface between the host cancellous bone and nacre. These phenomena resulted in the total integration of the implant.

The present work deals with the fabrication of forsterite–hydroxyapatite (FS–HA) hybrid coatings on stainless-steel 316L using the pulsed laser deposition (PLD) technique. The stainless steel (SS 316L) as a metallic implant is widely used in hard tissue applications. The XRD studies have confirmed the crystalline behavior of synthesized FS powder with an average crystallite size of 54 nm. The synthesized FS powder was mixed in different compositions (10, 20, 30 wt.%) into HA for preparing PLD targets (pellets). The XRD of the prepared pellets by UTM has confirmed both phases of FS and HA. The Scanning Electron Microscopy (SEM) of the coated samples depicted the successful deposition of composite powders on the substrates (SS 316 L). The Ellipsometer was used to investigate the thickness of different substrates and it was found as 243, 251, 255, and 257 nm for CP1, CP2, CP3, and CP4, respectively. The bioactivity of the coated substrates with different compositions (pure HA, 10%, 20%, 30%, and pure FS) was investigated by immersing the samples in simulated body fluid (SBF) for 14 days. The same samples were then characterized by SEM which confirms the apatite layer formation that reflects the bioactivity. The addition of FS powder into HA will stimulate the apatite formation which enhances the bioactivity. The Raman Spectroscopy of coated samples reveals the successful deposition of different compositions of FS–HA nanocomposite. The peaks of Raman spectroscopy were corresponding to the XRD results of the pellets (different compositions of FS–HA). The antimicrobial activity of different compositions of FS–HA against Escherichia coli (E. coli) bacteria also showed a significant zone of inhibition. The bioactivity and antimicrobial behavior of FS–HA along with successful deposition by PLD have shown better potential applications for biomedical implant coating.