SUPPLEMENT

ARY
DIAGNOSTIC
AIDS
Dr. Rajshekhar Banerjee
II MDS, Dept. of Orthodontics and Dentofacial
Orthopaedics,
AB Shetty Memorial Institute of Dental
2 Contents
1. Introduction
2. Cephalometric Radiography
3. Occlusal Radiography
4. Hand-wrist Radiography
5. Digital Subtraction Radiography
6. Occlusograms
7. Stereophotogrammetry
8. Holograms
9. Xeroradiography
10. Computed Tomography
11. CBCT
3 Contents
12. MRI
13. Ultrasonography
14. Digital Cineradiography
15. Electromyography
16. Bone scintigraphy
17. Structured Light
18. Laser scanning
19. Video Cephalometry
20. Digital Models
21. E-Models
22. Teleradiography
4 Introduction
▹ Greek word “DIAGNOEIE” meaning to
discern among, to know differences between.

▹ Diagnosis is the study and interpretation of

data concerning a clinical problem in order to
determine the presence or absence of an
abnormality.
-MOYERS
5
6

DIAGNOSTIC AIDS

Essential Supplemental
7 ESSENTIAL
▹ Case history
▹ Clinical examination
▹ Study casts
▹ Radiographs
▸ IOPA
▸ Bitewing
▸ OPG
▹ Facial photographs
 SUPPLEMENT
8 AL 8. Hormones
9. Computed tomography
1. Specialized radiographs
▸ Cephalometric 10. Cone beam computed
radiographs tomography (CBCT)
▸ Occlusal intra-oral 11. Scintigraphy
films 12. Structured light
2. Hand-wrist radiographs 13. Teleradiography
3. Digital Subtraction 14. Video-cephalometry
radiography 15. Bone markers
4. Electromyographic 16. Spectrophotogrammetry
examination of muscle
17. MRI
activity
18. Xeroradiography
5. Occlusograms
19. Ultrasonography
6. Holography
 Cephalometric
9 Radiography
▹ Specialised skull radiographs.

▹ Introduced to the dental profession by Broadbent.

▹ Standardized technique.

▹ 2 types:-
▸ Lateral cephalogram
▸ Postero-anterior cephalogram
10
 Cephalometric
11 Radiography
Applications:
▹ Lateral cephalograms provide pertinent information
on skeletal, dental, and soft tissue morphology and
relationships.
▹ Postero-anterior cephalograms are used primarily to
assess skeletal and dental asymmetries.
▹ Important research tool for comparing craniofacial
parameters between populations
 Occlusal
12 Radiography
 Occlusal
13 Radiography

Topographical – Ant. Maxilla & dentition, ant. nasal fossa

Cross Sectional – Palate, Zygomatic Process of Maxilla,
nasolacrimal canal, nasal septum, 2nd Molar to 2nd Molar.
 Occlusal
14 Radiography

Anterior: From canine of one side to the contralateral side.

Cross Sectional: Lingual & Buccal Plates of the jaw bone
2nd molar to 2nd molar.
 Occlusal
15 Radiography
Uses:

▹ To precisely locate roots, supernumerary unerupted

and Impacted teeth (canine to 3rd molar)

▹ To aid in examining patients with trismus with

restricted mouth opening.
16

Hand Wrist
Radiography
 Hand Wrist
17 Radiography

▹ Hand wrist region-made up of numerous small

bones.
▹ These bones show a predictable and scheduled
pattern of appearance, ossification and union
from birth to maturity.
▹ Skeletal maturity status of an individual can be
determined.
 Hand Wrist
18 Radiography

Methods
▹ Atlas method –Grulich and Pyle
▹ Bjork, Grave and Brown method
▹ Fishman’s SMI
▹ Hagg and Taranger method
 Hand Wrist
19 Radiography
Uses-
▹ Discrepancy between the Dental an chronological age.
▹ Determine Skeletal Maturity Status prior to treatment
of Class II and Class III malocclusions.
▹ Assessment of skeletal age in patients whose growth
is affected by infections, trauma or neoplasms.
▹ To predict future skeletal maturity rate and status.
▹ Aid In Research - study The Role Of hereditary,
environment, nutrition etc. on skeletal maturation
pattern.
 Subtraction
20 Radiography
 Subtraction
21 Radiography

▹ Requires 2 identical images

▹ The subtracted image is a composite of these 2,

representing their differing densities.
 Subtraction
22 Radiography
 Subtraction
23 Radiography

▹ The strength of digital subtraction radiography is

that it cancels out the complex anatomic
background against which this change occurs.

▹ As a result, the conspicuousness of the change is

greatly increased.
 Subtraction
24 Radiography
 In order for DSR to be diagnostically useful, it is imperative that
the baseline projection geometry, & image intensities be
produced.
 The projection geometry is defined by the position & orientation
of the x-ray source, the patient, & the detector, relative to one
another.
 If the projection geometry used for the follow –up is different
from the projection geometry used for the baseline image, the
subtraction image will show these differences .
 They can be difficult to distinguish from actual changes within
the patient, or they may hide actual change.
 Subtraction
25 Radiography
Uses
 Diagnosis of periodontal and carious lesions, both of
which may be characterized by their sometimes insidious
& relatively slow rate of progression.

 Evaluating small changes in the mandibular condyle

position and the integrity of the articular surface.

 It is also useful for the assessment of osseous remodeling

around granular hydroxyapatite implants.
 Quantitative analysis of apical root resorption
by means of digital subtraction radiography
26
Min-Suk Heo, DDS, MSD, Sam-Sun Lee, DDS, MSD, PhD, Kyung-Hee Lee,
DDS, MSD, Hang-Moon Choi, DDS, MSD, Soon-Chul Choi, DDS, MSD, PhD,
and Tae-Won Park, DDS, MSD, PhD, Seoul, Korea
Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, & Endodontics.
March 2001.

Objective:
This study was performed to assess the diagnostic and quantifying
ability of digital subtraction images for simulated apical root
resorption, as well as to compare the diagnostic accuracy of
conventional intraoral radiographs with digital subtraction images for
this condition.
 Quantitative analysis of apical root resorption
by means of digital subtraction radiography
27
Min-Suk Heo, DDS, MSD, Sam-Sun Lee, DDS, MSD, PhD, Kyung-Hee Lee,
DDS, MSD, Hang-Moon Choi, DDS, MSD, Soon-Chul Choi, DDS, MSD, PhD,
and Tae-Won Park, DDS, MSD, PhD, Seoul, Korea
Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, & Endodontics.
March 2001.

Conclusion:
A quantitative analysis of small amounts of apical root resorption can
be performed by means of digital subtraction radiography.
28 Occlusograms
29 Occlusograms

▹ Involves positive-print 1:1 photographs of dental

casts. The tracings of these photographs are called
as occlusograms.

▹ These are actual size photographs of the occlusal

surface of the dental cast.

▹ Developed by C.J BURSTONE in 1961.

30 Occlusograms
▹ 4 into 5 inch box camera mounted on a sliding rack so
that the distance from the track is adjusted.
▹ Registration track on the oclusostat for the placement
of the cast.
▹ The recommended focal length of the camera :210mm
and can be stopped down to F:45 for the best depth of
field.
31 Occlusograms
 Impressions are made-casts are poured and trimmed.
 The posterior borders are trimmed perpendicular to the
occlusal plane and the palatal midline. They are in
flush with each other when the casts are in C.R. The
bases are parallel to the occlusal plane.
 Wax jaw registration is made with the mandible in most
retruded position, recording the occlusal surfaces
without perforating the wax.
 For lateral orientation each cast has an extended
registration groove.
 The casts are then finished and polished.
32 Occlusogram Tracing
▹ For the occlusogram tracing acetate paper with the rough side
up is placed over the occlusograms and the max. and mand.
teeth are outlined, showing the gingival tooth contour, incisal
edges, buccal cusp ridges, central grooves & cusp tips, the
upper & lower registration lines, mid-sagittal reference line
based on the mid palatal raphe & incisive papilla. “R” & “L”
should be marked on the right and left sides to avoid confusion.
 Occlusogram Technique Using
33 Photocopying
 The study models are prepared as described
earlier.

 With models in the centric relation & teeth in

occlusion three marks on each model are made.
i.e. on the rt. & lt. side of the buccal segment & in
the midline.

 The casts are then photocopied on a photocopy

machine and the occlusal photocopy is used to
obtain a tracing.
 Orthodontic Application of
34 Occlusograms
• Determination of arch form & width.

• Arch length discrepancies (crowding or spacing)

• To estimate occlusal relationships.

• To estimate tooth movements in all three planes.

• Anchorage requirements in each quadrant for

extraction cases.
 Orthodontic Application of
35 Occlusograms
• Presence and extent of tooth mass discrepancies.

• Determines changes in the cant of occlusal plane.

• Aid in arch wire construction.

• Growth changes in the arch can be seen with the

help of the tracings.

• Quantifying treatment progress.

36 Disadvantages of Occlusograms

• Not very accurate.

• Time consuming

• Possibility of using a occlusogram with a head film

produces difference in magnification.
 3D Occlusogram
37 Software
The procedure includes :

1. Image scanning & setting.

2. Occlusal view processing.

3. Lateral cephalometric processing.

4. Occlusogram construction .
 3D Occlusogram
38 Software
Advantages
 Combination of lateral cephalometric image with the
occlusal views of the upper & lower dental casts
complete the 3 dimensional set up of the patient.
 Demonstrates all the treatment possibilities. The
needed movements of the teeth are clearly visible on
the occlusal views in the 3 planes of space allowing
the design for the “custom made appliance” & the
lateral cephalogram shows the planned displacement
for the molars & the incisors.
 3D Occlusogram
39 Software
Advantages
 The software can simulate the results of standard
surgical procedures.
 Ease in using
 Accurate, precise & Rapid
 Stereo
40 Photogrammetry

▹ Involves photographing a three-dimensional object from

two different coplanar views in order to derive a three
dimensional reconstruction of the images.

▹ Allows tracking of relative changes in the location of the

landmarks as a result of growth, development,
mandibular movement, injury, skeletal malformation &
treatment.
 Stereo
41 Photogrammetry

▹ Two photographs are taken with 2 semi-metric cameras,

which form a STEREOPAIR. The cameras are mounted
on a frame with a dist. Of 50cm b/w them,& positioned
convergently with an angle of 15 degrees. With the use
of a analytical plotter & a stereopair a 3 dimensional
image of an object is created.
 42

160-180
degree
image
capture
system
designed
to capture
the face.
 43

360 degree
image
capture
system for
imaging the
entire head
and face
44
45
 Stereo
46 Photogrammetry
Orthodontic Applications
▹ Quantifies facial morphology for the purpose of diagnosis.
▹ Detects changes in the facial morphology during growth and
development.
▹ Detects asymmetries.
▹ Helpful in assessing facial contour, surface appearance of the
face.
▹ Evaluation of treatment results.
▹ Quantitative data on facial proportions & profile indices.
▹ The life like 3D model of the patient can be rotated enlarged,
measured in 3 dimensions as required for diagnoses.
47 Holograms
▹ Holography uses laser light to reproduce a very high
quality, three dimensional image of the cast. The recorded
image is called a HOLOGRAM.
▹ The holograms obtained permit three dimensional model
analysis, superimpositions, and storage.
48 Holograms

System
▹ Holocamera
▹ Automatic Developer
▹ Illumination Element
▹ Measuring Element

Inside of holocamera. Laser He-Neon

mirrors and cast model in plate folder.
49 Holograms

Holocamera

▹ Procedure: The model being

photographed is placed on a glass plate
for exposure.

▹ Laser beam being used in the camera is

divergent
50 Holograms
Automatic Developer
▹ Designed to develop exposed plates without the need for
personnel experienced in holography
▹ The holder carries the plates from tray to tray throughout
the development process.
51 Holograms

Illumination Element

▹ Consists of a mounted Halogen lamp

▹ The light holder position can change the
height and the angle to illuminate the
hologram in the best possible way.
52 Holograms
Measurement Element
▹ It is a plate holder mounted on an x-y-z micropositioner
to allow a precision of 0.01 mm.
▹ The z micropo-
sitioner has an
optical fiber
connected to a
laser diode
that projects a
small red spot
light used for
depth
measurements.
53 Holograms
Orthodontic Applications
▹ Measurement of incisor intrusion.
▹ Study the effects of high pull headgear.
▹ Tooth position measurements.
▹ Study the effect of maxillary expansion on facial skeleton.
▹ Study the effect of class 2 elastics on bone displacement.
▹ Study the effect of cervical headgear on maxilla.
▹ Facial and dental arch symmetry.
▹ Determine the center of rotation produced by orthodontic
forces.
▹ Lower incisor space analysis.
54 Holograms
Advantages
▹ Superimposition of images is possible, thus detection of any
changes and tooth movement are possible.

▹ Holographic image can be measured in 3 dimensions.

▹ Ease in storage, transportation

▹ Cost similar to conventional photography.

55 Holograms
Disadvantages
▹ Inability to place the holograms immediately next to
the patient’s mouth to make side by side comparisons.

▹ Cannot be adjusted once made.

 Xeroradiograp
56 hy

▹ Xeroradiography
is a type of x-ray
in which a picture
of the body is
recorded on paper
rather than on
film.
 Xeroradiograp
57 hy
 In this technique, a plate of selenium, which rests
on a thin layer of aluminium oxide, is charged
uniformly by passing it in front of a 'scorotron'.
 As X-ray photon impinges on this amorphous coat
of selenium, charges diffuse out, in proportion to
energy content of the X-ray.
 This occurs as a result of photoconduction. The
resulting imprint, in the form of charge distribution
on the plate, attracts toner particles, which is then
transferred to reusable paper plates.
 Xeroradiograp
58 hy
 A positive xeroradiograph refers to an image
which is blue and white, with blue representing the
dense areas.

 A negative xeroradiograph refers to an image that

is blue and white but has been reversed, so that
white represents the dense areas
 Xeroradiograp
59 hy
 In contrast to conventional X-rays, photographic
developers are not needed. Hence the term
xeroradiography; 'xero' meaning dry in Greek.

 It requires more radiation exposure.

 Xeroradiograp
60 hy
Advantages
 Pronounced edge enhancement
 A choice of positive and negative display
 Good detail
 Wide exposure latitude
 No need of silver halide coated films.

Disadvantages
 High radiation exposure
 Xeroradiograp
61 hy
Types of Xeroradiographic Systems
Two types –
1. The Medical 125 system
▸ Used since 1970’s.
▸ Used manly in Mammography and general
radiography.
▸ Also been used for Cephalometric
radiography and Tomography of the TMJ
2. The Dental 110 system
▸ Designed for dental Xeroradiographs
 Xeroradiography vs.
62 Radiography
▹ Elimination of accidental film exposure.

▹ High resolution

▹ Simultaneous evaluation of multiple tissues

▹ Economic

▹ Does not involve wet chemicals or the use

of dark rooms
 A cephalometric appraisal of Xeroradiography
63 by Chate – AJODO 1980
Aim : To estimate the effect of xeroradiographic technique on
the degree of inter and intra observer error in cephalometric
landmarks identification.
Method
 This study involved identification by four observers of 16
cephalometric landmarks on 12 xeroradiographs & on 12
radiographs, on 2 separate occasions.
Conclusion
 Neither technique provided a significant decrease in
interobserver differences.
 However, for 8 of 32 variables, xeroradiography produced a
significant reduction in intraobserver error in comparison to
radiography.
 Computed
64 Tomography
▹ Invented by Sir Godfrey
Hounsfield in 1972

▹ CT is an image display of the

anatomy of a thin slice of the
body developed from multiple
x- ray absorption
measurements made around
the body’s periphery
 Computed
65 Tomography
▹ A CT scanner consists of an x-ray tube that emits a finely
collimated, fan-shaped x-ray beam directed through a patient
to a series of scintillation detectors or ionization chambers
 66

Multi-
detector
Helical CT
 Computed
67 Tomography

Parts of the Equipment;

▹ Scanner ( movable x -ray
table + gantry)
▹ Computer system
▹ A display console
 Computed
68 Tomography
Principle;
 A x ray source and array of detectors
mounted within the gantry rotate around
the patient during each scan.
 Detectors record the attenuation values of
the beam emerging from the patient
 Information from each traverse is a Profile
 Computed
69 Tomography
▹The tube and detectors are further angled and
another traverse is made.
▹A series of Profiles is built up.
▹The computer analyses
the data and an image is
produced.
 Computed
70 Tomography
Early scanners
▹ Translate and rotate system.

Recently developed scanners

▹ stationary detectors and x ray tube rotates
around the patient
▹ both the detectors and x ray tube rotate in
synchrony
 Advantages of CT
71  Completely eliminates the super imposition of
images of structures.
 Differences may be distinguished between tissues.
 Multi planning imaging is possible.
 Confines the radiation to the plane of interest.
 Minimizes blurring.
 Permits visualization of small variations in tissue
density.
 CT produces superb contrast resolution of soft
tissues.
 CT image without using invasive contrast material.
72 Disadvantages
 Too time consuming.
 Expensive for routine clinical use.
 Patient is exposed to high amounts of radiation.
 The equipment is very expensive and therefore not
always accessible.
 Microcomputed
73 Tomography
▹ Principally the same as CT, except that the
reconstructed cross sections are confined to a much
smaller area.

▹ Significantly reduces radiation dosage.

▹ Used to measure bone connectivity in all 3

dimensions
 Cone-Beam Computed
74 Tomography
▹ It uses a divergent or “ cone ” -shaped source of ionizing
radiation and a two-dimensional area detector fixed on a
rotating gantry to acquire multiple sequential projection
images in one complete scan around the area of interest
 Cone-Beam Computed
75 Tomography
There are four components to
CBCT image acquisition:
▹ X-ray generation

▹ Image detection system

▹ Image reconstruction

▹ Image display
76 Advantages of CBCT
▹ Reduced cost compared to conventional CT

▹ Reduced size compared to conventional CT

▹ High speed scanning.

▹ Uses megapixel solid-state devices for x-ray

detection. These devices provide submillimeter
pixel resolution of component basis projection
images.
77 Advantages of CBCT
▹ Low patient radiation dose.

▹ Has interactive analysis. Provides the practitioner

with an interactive capability for real-time
dimensional assessment, annotation, and
measurements.
78 Disadvantages of CBCT
▹ Does not map out muscle structures and their
attachments. Poor soft tissue contrast
▹ High image noise.
▹ Long capture time for the full view of the subject:
30-40 secs; during which involuntary muscle
movements (eg: breathing) will lead to
inaccuracies in the soft tissue capture.
▹ High maintenance.
 Unique contributions of
79 CBCT in Orthodontics
▹ It offers the advantages of a 3D rendering of facial
structures without magnification or distortion.
▹ It also provides cross-sectional views of the hard and soft
tissues, without superimpositions, thus allowing improved
location of the anatomical landmarks used in the
cephalometric analysis and accurate linear measurements
and angulations between the landmarks not on the same
plane.
 Unique contributions of
80 CBCT in Orthodontics
▹ It offers improved means for assessing treatment
outcomes & different patterns of bone remodeling
following orthognathic surgery.
▹ Cone beam imaging of impacted canine can show the
presence or absence of the canine, size of follicle ,
inclination of long axis of tooth, labial to palatal position,
etc.
▹ Measuring the size & shape of the pharynx is critical to
diagnose obstructive sleep apnea . In cross – section the
pharynx is more elliptical than round & thus 2D
information from a lateral cephalogram may be
insufficient or misleading for its diagnosis
 Unique contributions of
81 CBCT in Orthodontics
▹ Cone beam imaging can be used to determine the
thickness & morphology of bone at sites including where
mini- implants may be placed or in patients for whom
rapid maxillary expansion is being considered.
▹ It provide the opportunity to examine the facial
asymmetries , soft tissues & the airway in 3D.
 Limitations for use in
82 Orthodontics
▹ Supine position of the patient during scanning with some
machines may alter the position of the facial soft tissues.
However this is the preferred position for evaluation for
sleep apnea.

▹ Metal artifacts from dental restorations & implants

compromise image quality in the occlusal plane.

▹ The effective dose from conventional panoramic &

cephalometric views is much less than from cone beam
examinations.
 Magnetic Resonance
83 Imaging (MRI)
 Magnetic Resonance
84 Imaging (MRI)
▹ To make a magnetic resonance image, the patient is
first placed inside a large magnet.
▹ This magnetic field causes the nuclei of many atoms
in the body, particularly hydrogen, to align with the
magnetic field.
▹ The scanner then directs a radiofrequency (RF)
pulse into the patient, causing some hydrogen nuclei
to absorb energy (resonate).
 Magnetic Resonance
85 Imaging (MRI)
▹ When the RF pulse is
turned off, the stored
energy is released from the
body and detected as a
signal in a coil in the
scanner. This signal is used
to construct the magnetic
resonance image, in
essence a map of the
distribution of hydrogen.
 Magnetic Resonance
86 Imaging (MRI)
▹ Cortical bone and teeth with low presence of
hydrogen are poorly imaged and appear black.
▹ MRI can clearly differentiate the soft tissue
components.
▹ Preferred imaging technique when information
regarding the articular disc or the presence of
adhesions, or joint effusion is desired
 Magnetic Resonance
87 Imaging (MRI)
Equipment;
▹ The Gantry: Houses the patient. Patient is
surrounded by magnetic coils
▹ Operating console: Where the operator controls the
computer and scanning procedure
▹ Computer room network.
 Magnetic Resonance
88 Imaging (MRI)
Indications
▹ Assessing diseases of the TMJ

▹ Cleft lip and palate

▹ Tonsillitis and adenoiditis

▹ Cysts and infections

▹ Tumors
 Magnetic Resonance
89 Imaging (MRI)
Contraindications
▹ Patients with cardiac pacemakers.

▹ Patients with cerebral metallic aneurysm clips.

Slight movement of the clip could produce bleeding
▹ Stainless steel and other metals produce artifacts;
obliterate image details of the facial area.
 Magnetic Resonance
90 Imaging (MRI)
Orthodontic Considerations
▹ Orthodontists should have an understanding of MRI
techniques in order to understand how orthodontic
appliances in-situ may affect the diagnostic quality
of these scans. In addition the orthodontist should
be aware of the procedures to be followed, should a
patient wearing fixed orthodontic appliances require
an MRI scan.
 Magnetic Resonance
91 Imaging (MRI)
Orthodontic Considerations
▹ All metals used in orthodontics can produce
artefacts on MR images to varying degrees.
▹ Fixed components of orthodontic appliances, such
as brackets and bonds, can be left in place unless
they lie in the area of investigation.
▹ Stainless steel archwires, removable orthodontic
appliances, removable palatal bars and lingual
arches should be removed prior to the scan.
92 Ultrasonography
▹ It is a diagnostic medical
imaging technique used to
visualize muscles, tendons, and
many internal organs, to capture
their size, structure and any
pathological lesions with real
time tomographic images.
93 Ultrasonography
▹ By definition , Ultrasound has a
periodicity greater than 20 KHZ.

▹ Diagnostic ultrasonography
( sonography) , uses vibratory
frequencies in the range of 1 to
20 MHZ.
94 Ultrasonography
▹ Scanners used for sonography
generate electrical impulses that
are converted into ultra high
frequency sound waves by a
transducer, which is a device
that can convert one form of
energy into another; in this case
electrical energy into sonic
energy.
95 Ultrasonography
▹ The most important component
of transducer is a thin
piezoelectrical crystal or
material made up of a greater
number of dipoles arranged in a
geometric pattern.

▹ Currently , the most widely used

piezoelectric
material is lead zirconate.
96 Ultrasonography
▹ The most important component
of transducer is a thin
piezoelectrical crystal or
material made up of a greater
number of dipoles arranged in a
geometric pattern.

▹ Currently , the most widely used

piezoelectric
material is lead zirconate.
97 Ultrasonography
▹ As the ultrasonic beam passes through or interacts with
tissues of different acoustic impedance , it is attenuated by
a combination of absorption, reflection, refraction and
diffusion.

▹ Sonic waves that are reflected back (echoed) toward the

transducer cause a change in the thickness of the
piezoelectric crystal, which in turn produces an electric
signal that is amplified, processed, & ultimately displayed
on a monitor.

▹ In this system, the transducer serves as both a transmitter

and a receiver.
98 Ultrasonography
▹ In contrast to x- ray imaging , in which the image
is produced by transmitted radiation , the image
in sonography is produced by the reflected
portion of the beam.

▹ The fraction of the beam that is reflected back to

the transducer depends on the acoustic
impedance of the tissue which further depends
on the density of the tissue & the angle of the
beam.
 Digital
99 Cineradiography
 This is basically a radiographic motion picture.

 The subject is oriented properly and stabilized in a

modified cephalostat.

 An X-ray motion picture is obtained using a cine camera

which runs at 240 frames per second.

 This diagnostic aid is used to visualize the swallowing

pattern of the patient.

 The X-ray motion picture is studied using a movie

projector.
 Digital
10 Cineradiography
0
LIMITATIONS:

 The images captured by

Digital cameras that have
poorer spatial resolution
than that of film.

Cineradiography showing
various steps involved in
swallowing.
 Digital
10 Imaging
1
Analogue Image
▹ An analog image, such as a radiographic film, has
virtually an infinite number of elements, with each
element represented by a continuous gray scale.

Digital Image
▹ A digital image is a matrix of square pieces, or
picture elements (pixels), that form a mosaic pattern
from which the original image can be reconstructed
for visual display.
 Analogue Digital
10
2
 Acquisition of Digital
10 Radiographic Images
3

1. Indirect
2. Direct
3. Semi-Direct
 Indirect
10 Acquisition
4
Flatbed Scanners

▹ Simplest and least expensive

▹ Conventional X-Ray films are
placed in the scanner and scanned
by a light source.
▹ Transmitted light is detected using
a charged couple device and
digitized to grey scale images.
 Direct Image
10 Acquisition
5

▹ Charged Coupled Device (CCD)

▹ Complementary metal oxide

semiconductor (CMOS)
10 Charge Couple Device
6
▹ First developed in 1969 by Dr. Willard Boyle
and Dr. George Smith at Bell labs.
▹ Currently CCD technology is used in many
devices like fax machines, video cameras,
microscopes and telescopes.
▹ The CCD is a solid state detector that contains a
silicon chip with an electronic circuit embedded
in it.
▹ This silicon chip is sensitive to x-rays or light
10 Charge Couple Device
7
▹ The x-ray photons that come into contact with the
CCD cause electrons to be released from the silicon
and produce a corresponding electronic charge.
▹ The electrons that make up the silicon CCD -divided
into blocks or picture elements known as pixels.
▹ A pixel is a small box or “well” into which the
electrons produced by the x-ray exposure are
deposited.
▹ The CCD is 640 x 480 individual pixels in size.
10
8

X ray source CCD

Electron beam

Image
10
9
 Complementary metal oxide
11 semiconductor (CMOS)
0
▹ Good power dissipation and better functions
▹ Cheaper than CCD’s
▹ Used in security cameras, bar code scanners and
biometrics.
▹ Poor image quality
▹ CMOS + Active Pixel Sensors (APS) are the latest
development in direct digital sensor imaging but cost
factor is an issue.
11 Semi-Direct Acquisition
1
▹ Uses Photostimulable phosphor plates.
▹ The Imaging Plate is exposed to
conventional X-Ray Tube.
▹ Latent image is formed. The plate is placed
in a Laser Scanner
▹ Stimulates plates to emit visible light
proportional to the exposure.
▹ Light is detected by a “Image Reader”and
is converted to grey scale intensities
 Advantages of Semi-Direct
11 Acquisition
2
▹ There is less radiation exposure.
▹ The plates are reusable.
Placing the plate in bright light for few
minutes removes the latent image.

Available in 3 sizes.
▸ Cephalometric
▸ Panoramic
▸ Intra-oral sizes
 Advantages of Digital
11 Radiography
3
▹ About 50% - 70% less radiation than conventional
radiography
▹ Immediate picture
▹ Image improvable with image processing
▹ Elimination of darkroom, film, and chemical
processing
▹ Reduce cost of daily maintenances
▹ Easy to share by digital networking
▹ Easy to store.
▹ Easy for client education
 Disadvantages of Digital
11 Radiography
4

▹ Expensive.
▹ Spare parts are expensive.
▹ System, network, and database safety and security.
▹ Need for potential training..
▹ Cross infection
▹ Medico legal concerns
11 Electromyography
5

▹ Electromyography is a
medical technique for
evaluating and
recording physiologic
properties of muscle at
rest and while
contracting.
11 Electromyography
6
▹ EMG is performed
using a instrument
called an
electromyograph, to
produce a record called
an electromyogram.

▹ An electromyograph
detects the electrical
potential generated by
muscle cells when these
cells contract and also
when cells are at rest.
11 Uses of Electromyography
7

▹ Helps to distinguish primary muscle conditions from

muscle weakness caused by neurologic disorders.

▹ It is used to find causes of muscle weakness,

hyperactivity, paralysis, involuntary twitching, and
abnormal levels of muscle enzymes.
11 Uses of Electromyography
8
▹ In severe class II Div. I cases the upper lip
is hypofunctional. Thus during
swallowing, the lower lip extends
upwards and forwards to force the maxilla
labially and a strong mentalis activity is
seen. EMG can be used to study such
condition
11 Uses of Electromyography
9
▹ Abnormal buccinator activity in class II
malocclusion.

▹ Overclosure of jaws is associated with

accentuated temporalis muscle activity.
 Scintigraphy
12 (Bone Scanning)
0

▹ It is a nuclear medicine
imaging technique of the
bone.
 Scintigraphy
12 (Bone Scanning)
1
▹ Uses small amounts of
radioactive materials called
radiotracers that are injected
into the bloodstream. The
radiotracer travels through the
area being examined and gives
off radiation in the form of
gamma rays which are
detected by a special gamma
camera and a computer to
create images of your bones.
 Scintigraphy
12 (Bone Scanning)
2
▹ Because it is able to
pinpoint molecular
activity within the body,
skeletal scintigraphy
offers the potential to
identify disease in its
earliest stages.
 The use of bone scintigraphy in
temporomandibular joint disorders
12
3
▹ 2 recent development in this are
SPECT (Single Photon Emission
Computed Tomography) & other is
PET ( Positron Emission Computed
Tomography).

▹ In the SPECT, either multiple

detectors or a single moving detector
allows acquisition of data from a
number of contiguous transaxial
slices, similar to CT by x- ray.
 The use of bone scintigraphy in
12 temporomandibular joint disorders
4 JB Epstein, A Rea, O Chahal
Oral Diseases (2002)

▹ The use of bone scans as an additional tool in

diagnosing TMJ disease was assessed in this
series of patients.

▹ Concluded that bone scintigraphy may be

valuable to assess progress of TMJ inflammation
or remodeling, and may affect diagnosis and
treatment of patients with TMJ tenderness.
12 Structured Light
5
▹ The principle behind structured light systems is the
projection of a pattern onto a surface that is distorted
and interpreted as 3D information to produce a surface
map.

▹ Patterns that are used vary from lines, grids, circles and
other designs.

▹ An example of this is the basic system from eyetronics

that uses a 35-mm slide projector to project a grid
pattern & a common digital camera to record images .
12 Structured Light
6
12 Structured Light
7

▹ A structured light scanner

12 Structured Light
8

▹ Reconstruction of 3D image
▹ Different perspectives are combined in a process called
Stitching to produce one model
12 Suresmile System
9
 The two general approach to produce 3-D models of the
dental crowns are
 Direct method
 Indirect method
Destructive
Non-destructive(laser based)
13 Suresmile System
0
 It is based on Structured Light
Principles.
 An intraoral camera is used to
produce images for 3D modelling.
 After isolation of the dentition and
application of an opaquing agent,
small postage stamp sized images of
the dentition are taken with a video
camera while a light pattern is
strobed onto the teeth
13 Suresmile System
1

 The images are transmitted to a

computer where they are
registered and the data is
processed to remove artifacts and
redundant points. The complete
dental arch is imaged in about 90
seconds.
 Laser
13 Scanning
2
▹ Another popular
technology for 3D facial
imaging involves the use
of lasers.

▹ Light Amplification (by)

Stimulated Emission (of)
Radiation
 Laser
13 Scanning
3

▹ A laser beam is
“deflected” from a mirror
onto a physical object,
the beam is scattered, and
this is then captured on a
detector.
13 Types of Laser Scanners
4
Fixed units:
▹ Medical Graphics and Imaging Group system
▹ Cyberware Laboratory 3030/SP
▹ Others

Portable and mobile:

▹ Minolta Systems
▹ Fastscan
 Minolta Laser
13 Scanner
5
▹ Marketed globally by –
Konica Minolta; Minolta Co, Ltd, Japan

▹ VI- 700 was the 1st laser scanner

▹ By trangulating- length, width and also the depth

was calculated.
13
6 AJODO – Oct 2002

▹ Assessed the reliability of generating 3D object

reconstructions using the Minolta Vivid700 3D
surface laser scanner.

▹ The findings suggested that the surface laser scanner

has great research potential because of its accuracy
and ease of use. Treatment changes, growth, surgical
simulations, and many other orthodontic applications
can be approached 3-dimensionally with this device.
13 Laser Scanning
7
▹ Laser scanners are
capable of producing
detailed models
▹ However, the scanning
process requires the
subject to remain still for
a period of seconds to a
minute or more while the
scanner revolves around
the subject’s head.
 Video-
13 Cephalometry
8

▹ “Video imaging technology is a

method in which an Orthodontist
gathers facial, frontal and dental
images, and modifies them to
project potentially esthetic
treatment goals”
~Sarver
 Video-
13 Cephalometry
9

▹ Computerized video-imaging technology offers a

mutual visual template by which dentists,
orthodontists, oral & maxillofacial surgeons & plastic
surgeons can effectively communicate with patients &
each other.

▹ Beyond the communication value, video-imaging

technology allows greater potential for quantification
of treatment plans so that we maximize our chances of
delivering the proposed treatment plan
14 Digigraph
0
 It is one videoimaging computer capable of generating a 2D
or 3D facial analysis.
 Product of Dolphin imaging system.
 Developed by Dr Mark Lemschen & Mr Gary Engel ,
 Comprises a computer , a monitor & keyboard, an RVG
videocamera with light source, a sonic digitizing probe with
receptor microphones and a patient seat with a head holder
to stabilize the patient during digitizing.
 With the digigraph , any point can be located in the three
planes of space. Each point is transferred by the digigraph
into the x, y, z planes of space.
 Digigraph System
14 Design
1
▹ The DigiGraph Work
Station is about 5 feet
long, 3 feet wide and 7 feet
high.

▹ The main cabinet contains

the electronic circuitry,
and the patient sits next to
the cabinet in an adjustable
chair similar to those used
with cephalometers.
 Application of Digigraph in
14 orthodontics
2
1. Various cephalometric analysis like Steiner, Down,
Tweed, Holdaway etc. can be performed.
2. Superimposition can be done.
3. It is helpful in monitoring patient treatment
progress.
4. Facial asymmetries can be quantified.
5. Allows patient radiographs , photos, & models to be
stored on a small disk; reducing storage
requirements.
6. Valuable communicating tool for patient & between
their family & the referring dentists.
14
3
14 Digital Models
4
▹ Recent technological advances have allowed
the generation of digital dental models that
can be saved and viewed 3 dimensionally on
a computer.

▹ Here a traditional plaster model is fabricated

and using CAD-CAM technology, is
transformed into a digital, 3 dimensional
image of the dentition.
14 Digital Models
5

 An electronic file becomes available to be

downloaded from the internet to a desired
computer.

 Once downloaded, software enables the

digital models to be viewed and manipulated.
14 Digital Models
6

 The two major computerized model systems

creating digital models are OrthoCAD™
(Cadent, Inc, Fairview, NJ) and emodels™
(GeoDigm, Corp, Chanhassen, MN)
14
7
14
8

OrthoCAD™ measurement tool demonstrating tooth width measurements.

14
9

OrthoCAD™ cross-sectioning tool demonstrating a vertical cutting of the

digital models to check overjet and overbite.
15
0

Jaws Alignment Tool demonstrating the occlusal contacts after moving the
mandibular model in different directions.
15
1

OrthoCAD™Bracket Placement demonstrating the placement of a bracket in the

desired position virtually onthe digital model
15
2
15
3

emodels™ measurement tool performing a Bolton analyses.

15
4

emodels™ articulation feature allows either a predetermined or a custom center of

rotation to be chosen.
15
5

emodels™ eplan™
demonstrating the simulation
of an extraction treatment
option.
It can be used to simulate
multiple treatment options
 Advantages of Digital
15 Models
6
▹ They do not run the risk of breakage or wearing away
with time and usage like plaster models do.
▹ Physical storage space is saved.
▹ Can be shared easily and viewed from multiple
devices at multiple locations.
▹ Excellent for patient education.
▹ Saves costs in the long run as materials required for
producing plaster models is saved.
15
7 AJODO, July 2003
▹ The purpose of this study was to evaluate the reliability of
the OrthoCAD system.
▹ Two independent examiners measured tooth size, overbite,
and overjet on both digital and plaster models. The results
were compared, and interexaminer reliability was assessed.
▹ The results showed a statistically significant difference
between the 2 groups for tooth size and overbite, with
the digital measurements smaller than the manual
measurements. However, the magnitude of these
differences ranged from 0.16 mm to 0.49 mm and can
be considered clinically not relevant.
15
8 Angle Orthodontist, July 2010
▹ Aim:
To compare the dimensional stability of four
impression materials over time and to compare
OraMetrix digital models vs traditional plaster
models.

▹ Conclusion:
Digital models produced by OraMetrix were not
clinically acceptable compared with plaster models.
 Teleradiolog
15 y
9

▹ Teleradiology—the ability to obtain images in one

location, transmit them over a distance, and view them
remotely for diagnostic or consultative purposes
▹ The transmission can be accomplished with a range of
electronic media including telephone lines, wide area
networks (WAN), and satellites.
 Teleradiolog
16 y
0

▹ Farman & Farag and Benson reported the successful

transmission of dental radiographs through telephone
lines & satellites.

▹ Jin-Woo Choi in a study in 2013 concluded “A

teleradiology system in general dental practice could
be helpful in the differential diagnosis of common
lesions and reduce unnecessary costs.”
 Teleradiolog
16 y
1
Possible applications of teleradiology in orthodontics
include :
▹ Referrals
▹ Consultations with other specialists
▹ Submission of images for insurance purposes and so
on

The advancement of teleradiology has raised some

concerns with regard to patient records confidentiality,
integrity of the transmitted imaged etc.
162 Conclusion
16 References
3
▹ Contemporary Orthodontics – William R. Proffit
▹ Orthodontics: Current Principles and Techniques – Graber, Vanarsdall & Vig
▹ Orthodontic Diagnosis – Rakosi, Jonas & Graber
▹ Oral Radiology: Principles and Interpretation – White and Pharoah
▹ Marcotte MR. The use of the occlusogram in planning orthodontic treatment.
American journal of orthodontics. 1976 Jun 1;69(6):655-67.
▹ White LW. The clinical use of occlusograms. Journal of clinical orthodontics:
JCO. 1982 Feb;16(2):92.
▹ Fiorelli G, Melsen B. The “3-D occlusogram” software. American journal of
orthodontics and dentofacial orthopedics. 1999 Sep 1;116(3):363-8.
▹ Heike CL, Upson K, Stuhaug E, Weinberg SM. 3D digital
stereophotogrammetry: a practical guide to facial image acquisition. Head &
face medicine. 2010 Dec;6(1):18.
16 References
4
▹ Ras F, Habets LL, van Ginkel FC, Prahl-Andersen B. Method for quantifying
facial asymmetry in three dimensions using stereophotogrammetry. The Angle
Orthodontist. 1995 Jun;65(3):233-9.
▹ Romeo A. Holograms in orthodontics: a universal system for the production,
development, and illumination of holograms for the storage and analysis of
dental casts. American Journal of Orthodontics and Dentofacial Orthopedics.
1995 Oct 1;108(4):443-7.
▹ Harradine N, Ortho M, Suominen R, Stephens C, Hathorn I, Ortho D, Brown I.
Holograms as substitutes for orthodontic study casts: a pilot clinical trial.
American Journal of Orthodontics and Dentofacial Orthopedics. 1990 Aug
1;98(2):110-6.
▹ Chate RA. A cephalometric appraisal of xeroradiography. American journal of
orthodontics. 1980 May 1;77(5):547-67.
▹ Seminars in Orthodontics. March 2009 , Volume 15, Issue 1, p1-84
16 References
5
▹ Patel A, Bhavra GS, O’neill JR. MRI scanning and orthodontics. Journal of
orthodontics. 2006 Dec 1;33(4):246-9.
▹ Epstein JB, Rea A, Chahal O. The use of bone scintigraphy in
temporomandibular joint disorders. Oral diseases. 2002 Jan;8(1):47-53.
▹ Mah J, Sachdeva R. Computer-assisted orthodontic treatment: the SureSmile
process. American Journal of Orthodontics and Dentofacial Orthopedics. 2001
Jul 1;120(1):85-7.
▹ Kusnoto B, Evans CA. Reliability of a 3D surface laser scanner for orthodontic
applications. American Journal of Orthodontics and Dentofacial Orthopedics.
2002 Oct 1;122(4):342-8.
▹ Baumrind S. Integrated three-dimensional craniofacialmapping: Background,
principles, and perspectives. InSeminars in Orthodontics 2001 Dec 1 (Vol. 7,
No. 4, pp. 223-232). WB Saunders.
16 References
6
▹ Peluso MJ, Josell SD, Levine SW, Lorei BJ. Digital models: an introduction.
InSeminars in Orthodontics 2004 Sep 1 (Vol. 10, No. 3, pp. 226-238). WB
Saunders.
▹ Torassian G, Kau CH, English JD, Powers J, Bussa HI, Marie Salas-Lopez A,
Corbett JA. Digital models vs plaster models using alginate and alginate
substitute materials. The Angle Orthodontist. 2010 Jul;80(4):662-9.
▹ Farman AG, Farag AA. Teleradiology for dentistry. Dental Clinics of North
America. 1993 Oct;37(4):669-81.
▹ Choi JW. Clinical usefulness of teleradiology in general dental practice.
Imaging science in dentistry. 2013 Jun 1;43(2):99-104.
▹ Thrall JH. Teleradiology Part I. History and clinical applications. Radiology.
2007 Jun;243(3):613-7.
16 Biomarkers
7
“cellular, biochemical or molecular alterations that are
measurable in biological media such as human tissues, cells,
or fluids.”
~Hulka et al

“A characteristic that can be measured and evaluated as an

indicator of normal biological processes, pathological
processes or pharmacologic responses to therapeutic
interventions”
~NIH Biomarkers Definitions
Working Group, 1998
 Important Biomarkers in
16 Orthodontic Tooth Movement
8
1. Tumour Necrosis Factor 8. Cysteine Proteinases
2. RANK/RANKL/Osteopr 9. Alkaline Phosphatase
otogerin System 10. Acid Phosphatase
3. Interleukin‑1 (receptor 11. Myeloperoxidase
antagonist) 1β, 2,6,8 12. Aspartate amino
4. Matrix transferase (AST) Lactate
Metalloproteinases dehydrogenase (LDH)
5. Prostaglandins
6. Transforming growth
factor‑α1
7. Epidermal Growth Factor
17
0

▹ Cytokines: The cytokines, prostaglandin E2, TNF-α,

MMPs play major role in the pathogenesis of periodontal
diseases. Bacteria induce tissue destruction indirectly by
activating host defense cells, which in turn produce and
release mediators that stimulate the effectors of
connective tissue break down. These mediate the
inflammatory process and acts as markers of
inflammation.
17
1
▹ Tumour Necrosis Factor (TNF): This manifest potent
proinflammatory and catabolic activities, and play key
roles in periodontal tissue breakdown . Elevated levels of
tumour necrosis factor-α (TNF-α) or interleukin 6 (IL-6
and adipokines are known risk factors for destructive
periodontal disease.
▹ There is a marked increases in TNFα in cells of the PDL
and alveolar bone during OTM
17
2
▹ RANK/RANKL/Osteoprotogerin System:
The TNF‑related ligand receptor activator of nuclear
factor‑kappa ligand (RANKL) and its two receptors,
receptor activator of nuclear factor‑kappa (RANK), and
osteoprotegerin (OPG), are known for involvement in
bone remodeling process.
▹ Receptor activator of nuclear factor‑kappa ligand
activates osteoclast formation and activation. The binding
of the RANK receptor on the Osteoclast lineage cell leads
to rapid differentiation of hematopoietic osteoclast
precursors to mature osteoclasts.
17
3
▹ Osteoprotegerin is a decoy receptor produced by
osteoblastic cells, which compete with RANK for
RANKL binding.
▹ Thus, the inhibition of the activity of RANKL in its
promoting osteoclast differentiation could be very helpful
in preventing movement of anchor teeth during
orthodontic treatment and a relapse during the post
treatment period.
17 ▹ Interleukin‑1 (receptor antagonist) 1β, 2,6,8:
4
Interleukin‑1 (IL‑1) are cytokines that affect bone
metabolism and OTM, has 2 forms – α and β – that
code different genes have similar actions. These
actions include attracting leukocytes and stimulating
endothelial cells, fibroblasts, osteoclasts, and
osteoblasts to enhance bone resorption and inhibit
bone formation.
▹ Tuncer et al. reported increased levels of IL‑8 at PDL
tension sites and proposed it to be a triggering factor
for bone remodeling.
▹ Another cytokine of the IL family with a stimulatory
effect on bone remodeling and osteoclast formation is
Il‑6.
17
5
▹ Matrix Metalloproteinases: MMPs are a family of
proteolytic enzymes that mediate the degradation of
extracellular matrix molecules, including interstitial and
basement membrane collagens, fibronectin, laminin, and
proteoglycan core protein. Matrix metalloproteinase
(MMP) -8, collagenase-2, is a key mediator of irreversible
tissue destruction in chronic periodontitis and detectable in
GCF.

▹ MMP‑2 can be used during very early stages of

orthodontic treatment as a marker for active tooth
movement.
17
6
▹ Prostaglandins: Bacteria induce tissue destruction
indirectly by activating host defence cells, which in turn
produce and release mediators that stimulate the effectors
of connective tissue break down including prostaglandin
E2. These mediate the inflammatory process and acts as
markers of inflammation. Prostaglandin E2 seen three
times more in inflammed tissues than in normal tissues.
▹ Induces bone resorption by activating osteoclastic cells.
17
7 ▹ Transforming growth factor‑α1:
Transforming growth factor is a family of polypeptides
produced by cells within the periodontium involved in
many biologic activities, including cell growth,
differentiation, and apoptosis, as well as in developmental
processes and bone remodeling.
▹ Uematsu et al. reported the presence of TGF‑.α1 in GCF
during OTM. His study showed a rapid and transient
increase associated with elevation of cytokine levels and
may reflect early stages of tooth mobilization.
17
8
▹ Epidermal growth factor
▹ Epidermal growth factor (EGF) is another cytokine
possibly associated with bone remodeling. Fibroblasts and
stromal cells produce it. Uematsu et al in a study reported
a transient elevation of EGF levels in GCF after
application of mechanical stress of an experimental tooth.
17
9
▹ Cysteine proteinases: Cathepsins B, L and H are a family
of intracellular cysteine proteinases which can degrade
extracellular components including collagen.
▹ The accumulation of Cathepsin B in GCF has been shown
to increase with OTM. They were increased around
osteoclasts and played a role in the decomposition of
exposed collagen fibers and collagen degradation
byproducts.
18
0

▹ Alkalinephosphatase-Alkaline phosphatase is thought to

play a role in bone metabolism and is found in PMNs.
▹ Acid phosphatase-Acid phosphate is present in
inflammatory cells and has been detected in GCF).
▹ There is an elevation in ALP activity during the time
when little tooth movement occurs and an increase in
ACP activity that coincides with maximum tooth
movement.
18
1

▹ Myeloperoxidase- Myeloperoxidase (MPO) is a potent

antibacterial enzyme produced by PMNs.
▹ Mean MPO activity increased in both the GCF and saliva
of orthodontic patients 2 hours after appliance activation
and they might be a good biomarker to assess
inflammation in orthodontic movement.
18
2
▹ Aspartate amino transferase (AST) Lactate
dehydrogenase (LDH).)-They are soluble cytoplasmic
enzymes which are confined to the cell cytoplasm but are
released by dead or dying cells. During periodontal tissue
destruction, they are released and passes with the
inflammatory exudates into GCF.
▹ The GCF AST activity is significantly elevated in both
tension and compression sites at days 7 and 14. This rise
is a consequence of a controlled trauma, which produces
cell death due to the mechanical force exerted on alveolar
bone and PDL. It positively relates with compression sites
caused by an OTM.
 Zero-Base
18 Orthodontics
3

▹ Under this system, treatment planning is based on the degree

of difficulty of each of a series of diagnostic elements.
▹ This approach results in treatment plans that are
individualized according to the specific needs of each
patient.
 Zero-Base
18 Orthodontics
4
18
5

Zero-
Base
Ortho
donti
cs
 References
▹ Kumar AA, Saravanan K, Kohila K, Kumar SS. Biomarkers in orthodontic
18
tooth movement. Journal of pharmacy & bioallied sciences. 2015 Aug;7(Suppl
6 2):S325.
▹ Anitha, Pratebha Balu,S.Sakthi Devi,Arun Kumar , Review :Biomarkers – A
Diagnostic Tool for Periodontal Diseases , Journal of Scientific Dentistry
2013;3(1):59-65
▹ Uematsu S, Mogi M, Deguchi T. Cytokine levels are elevated in gingival
crevicular fluid during human orthodontic tooth movement. In: Davidovitch Z,
Norton LA, editors. Biological Mechanisms of Tooth Movement and
Craniofacial Adaptation. Boston: Harvard Society for the Advancement of
Orthodontics; 1996. p. 223‑32.
▹ Uematsu S, Mogi M, Deguchi T. Interleukin (IL)‑1 beta, IL‑6, tumor necrosis
factor‑alpha, epidermal growth factor, and beta2‑microglobulin levels are
elevated in gingival crevicular fluid during human orthodontic tooth
movement. J Dent Res 1996;75:562‑7
▹ Uematsu S, Mogi M, Deguchi T. Increase of transforming growth factor ‑beta 1
in gingival crevicular fluid during human orthodontic tooth movement. Arch
Oral Biol 1996;41:1091‑5.
Thank you!