Unlock document.
This document is partially blurred.
Unlock all pages and 1 million more documents.
Get Access
e1
QUESTIONS
1. Classify the different types of chemical bonds within
and between molecules (intra- and inter-molecular
bonds. These can be expressed either as forces or as
interaction energies. What is the relationship between
these two physical quantities? Group these bonds in
(Hint: Start by consulting textbooks of basic physics
and physical chemistry.)
2. Undertake a literature search to compare the volume
of research being written in the past 25 years on: (a)
bone-cement fixation; and (b) cement-less fixation of
femoral orthopedic prostheses. Consult some current
professional orthopedic surgery journals to form an
3. Make a literature search to investigate methods of
determining the strength of bonds between adhesives
and hard-tissue substrates. Fracture mechanics (FM)
methods might be considered an ideal approach.
4. When new adhesive technologies are introduced into
biomedicine and applied to a population of subjects,
the question of survival statistics arises. Investigate
5. One experimental approach to investigating adhesive
failures is the examination of retrieved specimens
after revision surgery in, for example, orthopedics
(Hint: Consider optical imaging, to treat aspects of frac-
tography, along with high resolution electron micros-
copy and surface-chemical analytical techniques.)
ANSWERS
Primary Bonds Secondary Bonds
Joining atoms to
form molecules
Between (neighboring)
molecules or molecular
segments
• Covalent
electron pairs: X–Y
• Hydrogen bonds
O-H……O=
mechanical dipoles
These interactions can be expressed either as forces
or as interaction energies. The two physical quantities
are related. In classical physics, energy (U) is a quan-
Conversely, Force relates to energy as the distance-
derivative of energy:
numerically abundant in macromolecules contain-
ing, for example, –O–H and –NH2 functional groups.
Hence, their net effect is considerable and responsible
CHAPTER II.5.8
Adhesives and Sealants
e2
on: (a) bone-cement fixation; and (b) cement-less
fixation of femoral orthopedic prostheses.
You can search using Medline, PubMed, or more
generally the Web of Science. Set the delimiter for
the past 25 years, or as required. Appropriate search
terms are:
• bone-cement fixation
• cement-less femoral fixation or arthroplasty.
Professional orthopedic surgery journals include:
• Journal of Orthopaedic Surgery.
3. Make a literature search to investigate methods of
determining the strength of bonds between adhesives
and hard-tissue substrates.
Fracture mechanics (FM) methods might be con-
sidered an ideal approach. These generally study the
forces or energies required to propagate cracks of a
defined initial size through material specimens of a
defined geometry. See the paper by Söderholm cited
in Söderholm, K. -J. (2010). Review of the fracture
4. When new adhesive technologies are introduced into
biomedicine and applied to a population of subjects,
the question of survival statistics arises.
F
B
SENB Specimen
F
a
W
FIGURE II.5.8.2 The geometries of Compact Tension and Single-
Edge-Notched-Bend specimens for the determination of fracture
toughness of materials or of interfaces between pairs of bonded
materials.
FIGURE II.5.8.3 Kaplan–Meier plots of survival versus time for
populations of two different systems, coded red and green.
e3
5. One experimental approach to investigating adhesive
failures is the examination of retrieved specimens
after revision surgery in, for example, orthopedics or
dentistry.
Given a supply of tissues or biomaterial compo-
nents that have undergone failure, a protocol of
experimental investigations that could give insights
into failure mechanisms could be the following:
a. Examine the specimen under a zoom optical
microscope with an attached digital camera facil-
ity, recording images of the entire specimen at dif-
ferent magnifications.
b. Try to identify the failure-origin site. This might
be an internal defect or pore from which a crack
Identity Location Size
Nomenclature and
inherent spatial
distribution:
Spatial location
of an indi-
vidual origin
in a specific
specimen:
• Volume-distributed
• Surface-distributed
• Volume-located
• Surface-located
• Near-surface-
• Estimate of the
diameter for
equiaxed origins
inherently surface-distributed origins.
On the other hand, the terms may refer to the
specific location of a single origin in any particular
specimen or component.
For example, a pore (which is a volume-
distributed origin) could be located at the sur-
face of a particular specimen or component. A
volume- distributed origin type may be in the vol-
ume (bulk), at the surface, near the surface, or at
an edge.
c. High resolution images may be obtained of
microscopic surface regions by Scanning Electron
Microscopy (SEM), although non-metallic speci-
mens must first be treated by deposition of a con-
