This document discusses topographic analysis and physical testing of dental materials. It describes various methods for analyzing surface topography, including contact methods using a profilometer and non-contact methods like confocal microscopy, SEM, and atomic force microscopy. Physical testing methods are also outlined, such as using a rheometer, colorimeter, XRD, DSC, and pycnometry to analyze properties like flow, color, structure, thermal transitions, and density. References are provided for additional information on techniques like SEM, atomic force microscopy, and confocal microscopy.

1. Topographic analysis and physical
testing of dental materials
By
Mohamed Mahmoud Abdul-Monem
Assistant lecturer
Dental Biomaterials Department
Faculty of dentistry
Alexandria University
Egypt

2. Topographic analysis of
materials

3. • Surface topography is the local deviations of a
surface from a perfectly flat plane.
• The topography of a surface is known to
substantially affect the bulk properties of a
material.

4. • Surface topography may be measured in two ways:
1. Contact methods: Involve dragging a measurement
stylus (profilometer) across the surface.
2. Non-contact methods :
1. Confocal microscopy
2. Focus variation
3. Structured light
4. Electron microscopy
5. Photogrammetry

5. Topographic analysis
• Profilometer
• Stereo microscope
• Scanning electron microscope (SEM)
• Environmental SEM
• Scanning transmission electron microscope
• Atomic force microscopy
• Confcal microscopy
• Fluorescence microscopy

6. Profilometer

7. Stereo microscope
• A low powered
microscope which
provides a stereoscopic
view of the sample,
commonly used for
dissection.
• Typically using light
reflected from the
surface of an object
rather than transmitted
through it.

9. SEM
• A scanning electron
microscope (SEM) is a type
of electron microscope that
produces images of a
sample by scanning it with a
focused beam of electrons.
• The electrons interact with
atoms in the sample,
producing various signals
that contain information
about the sample's surface
topography and
composition.

11. Environmental SEM
• Samples are observed in low-
pressure gaseous
environments and high
relative humidity (up to 100%)
• ESEM is especially useful for
non-metallic and biological
materials because coating with
carbon or gold is unnecessary.
• Uncoated Plastics
and Elastomers can be
routinely examined, as can
uncoated biological samples.

13. Scanning transmission electron
microscope (STEM)
• The SEM can also be
used in transmission
mode by simply
incorporating an
appropriate detector
below a thin specimen
section .

16. Atomic Force Microscope
(scanning force microscope)
• Is a very-high-resolution
type of scanning probe
microscopy(SPM), with
demonstrated resolution on
the order of fractions of
a nanometer, more than
1000 times better than
the optical diffraction limit.
• The information is gathered
by "feeling" or "touching"
the surface with a
mechanical probe.

17. • Compared to competitive technologies such as optical
microscopy and electron microscopy, the major
difference between these and the atomic-force
microscope is that the latter does not use lenses or
beam irradiation.
• Applications in the field of solid state physics include:
(a) the identification of atoms at a surface,
(b) the evaluation of interactions between a specific atom
and its neighboring atoms, and
(c) the study of changes in physical properties arising
from changes in an atomic arrangement through
atomic manipulation.

20. Confocal laser scanning microscope
• Confocal : denoting or using a microscope whose
imaging system only collects light from a small spot on
the specimen, giving greater resolution.
• An optical imaging technique for increasing optical
resolution and contrast of a micrograph by means of
adding a spatial pinhole placed at the confocal plane of
the lens to eliminate out-of-focus light.
• It enables the reconstruction of three-dimensional
structures from the obtained images by collecting sets
of images at different depths (a process known
as optical sectioning) within a thick object.

21. • The Confocal Laser Scanning Microscope (CLSM)
is an optical microscope that includes a laser light
as a light source and an electronic system which
helps on image processing.
• It obtains high-resolution and extremely thin
optical image sections, removing the interference
caused by the light arriving from the different
optical fields across the thickness of the sample,
and focusing on a single plane (confocal).

25. Fluorescence microscopy
• Optical microscope that uses fluorescence in
addition to, reflection and absorption to study
properties of organic or inorganic substances.
• The specimen is illuminated with light of a
specific wavelength (or wavelengths) which is
absorbed by the fluorophores, causing them
to emit light of longer wavelengths (i.e., of a
different color than the absorbed light).

26. • Biological fluorescent stains
• Immunofluorescent stains
• Fluorescent proteins

28. Physical testing of materials

29. Physical testing of materials
• Rheometer
• Colorimeter
• XRD
• Differential scanning calorimeter
• Pycnometry
• Particle size analyzer
• Mercury dilatometer
• Optical tensiometer

30. Rheometer
• is a laboratory device
used to measure the
way in which a liquid,
suspension or slurry
flows in response to
applied forces.

32. colorimeter

33. XRD
• is a measuring
instrument for analyzing
the structure of a
material from
the scattering pattern
produced when a beam
of radiation or particles
(such as X-
rays or neutrons)
interacts with it.

35. Differential scanning calorimeter
• Differential scanning
calorimetry (DSC) is a
tool to determine a
series of temperature
transitions in materials,
such as the Tg and
melting temperature.

38. Pycnometry
• Pycnometry is a
technique used to
determine material
densities.
• It is also possible to
calculate volumetric
shrinkage in
polymerizations, by
equating the densities of
the material in the
monomeric and
polymeric states.

39. Particle size analyzer
• Particle size analysis, is
the technical
procedure which
determines the size
range, and/or the
mean size of the
particles in a powder or
liquid sample.

40. Mercury dilatometer
• The mercury
dilatometer method
uses the variation in
height of a mercury
column caused by
composite shrinkage to
calculate total
volumetric shrinkage.

41. Optical tensiometer
• Optical tensiometers are used in
research, quality control and
process control to study:
• wettability ·
• spreading ·
• absorption ·
• adsorption ·
• cleanliness ·
• surface tension ·
• interfacial tension ·
• contact angles ·
• surface heterogeneity ·
• interfacial rheology ·
• surface free energy

43. Porosimetry
• Porosimetry is an analytical technique used to
determine various quantifiable aspects of a
material's porous nature, such as pore diameter and
total pore volume
• The technique involves the intrusion of a non-
wetting liquid (often mercury) at high pressure into a
material through the use of a porosimeter.
• The pore size can be determined based on the external
pressure needed to force the liquid into a pore against
the opposing force of the liquid's surface tension.

45. References
1. Philips’ science of dental materials.12th edition
2. Craig’s restorative dental materials.13th edition
3. H Assender et al.How Surface Topography Relates to
Materials' Properties.Science Mag .2002;297
4. https://en.wikipedia.org/wiki/Scanning_electron_mic
roscope
5. M Vilotic et al.Atomic force microscopy in metal
forming and dental materials characterization.Journal
for technology of plasticity .2012;37:173-186
6. https://en.wikipedia.org/wiki/Confocal_microscopy

46. Thank You