Over the years, the research and applications of calcium phosphate materials
as nanocoatings for dental and biomedical applications have undergone a revolution to
become a state-of-the-art approach for improving osseointegration of implants and
devices. Determination of stresses within a nanocoating is vital as its mechanical
stability is governed by factors such as deposition method and heat treatments applied.
The presence of external mechanical loading as well as the possibility of the coating to
crack and spall because of inbuilt stresses (whether they are tensile or compressive)
will affect the successful deployment of biomaterial implants. The most commonly
used methods for characterizing the performance of micro- and nanocoatings on
substrates can generally be divided into the measurement of coating properties and
adhesion strength. Several excellent methods that can be used in thin film mechanical
properties evaluation, and some of the commonly used methods are nanoindentation,
tensile testing, scratch testing, adhesion and wear testing, pin-on-disk testing, pull-out
test, and bending and bulge testing. Furthermore, the biomechanical characteristics of
nanocoatings such as hydroxyapatite deposited on metallic substrates have also been
examined using nanomechanical testing and nanoindentation simulated via the finite
element approach.
Keywords: Anodization, Bone morphogenetic protein, Calcium phosphate,
Collagen, Drug delivery, Finite element analysis, Hydroxyapatite HAp, Interfacial
adhesion, Mechanical properties, Microtensile testing, Nanocoatings,
Nanocomposite coating, Nanoindentation, Peptide, Plasma spraying, Sol-gel,
Stem cell.
