5. Electromyography (EMG)
• technique for evaluating and recording the
electrical activity produced by skeletal muscles
• performed using an instrument called an
electromyograph to produce a record called
an electromyogram
6. EMG electrodes and its types
EMG
electrodes
surface
electrode
inserted
electrodes
Needle
electrodes
fine wire
electrodes
7. Needle Electrodes
• used in neuromuscular evaluations
• Needle electrode tip is bare and used as a
detection surface
• contains an insulated wire in the cannula
• conveniently inserted within the muscle so that
new tissue territories may be explored
8. Fine wire electrodes
• extremely fine; easily implanted and
withdrawn from skeletal muscles
• less painful but the cannula of needle
electrodes remains inserted in the muscle
throughout the duration of the test
9. Surface electrodes
• a non-invasive approach for EMG signal
measurement and detection
• Simple and very easy to implement
• Surface EMG electrodes require no medical
supervision and certification
• used for superficial muscles only
• With the skin their position must be kept
stable; otherwise, the signal is distorted
10. EMG Procedure
• Skin preparation
• impedance of the skin reduced
• Remove hair,where the
electrodes are to be placed
• Abrasive gel
• no moisture on the skin
• skin should be cleaned with
alcohol
11. • EMG electrode placement
• Between the tendinous
insertion and the motor
unit of the muscle
• along the longitudinal
midline of the muscle
• Between the electrodes or
detecting surfaces the
distance should be only 1-2
cm
12. Medical uses
• used as a diagnostics tool for
identifying neuromuscular diseases
• as a research tool for studying
kinesiology, and disorders of motor
control
• used to guide botulinum toxin or
phenol injections into muscles
• used as a control signal for prosthetic
devices such as prosthetic hands, arms,
and lower limbs
13. EMG in Dentistry
• Action potentials in
actively contracting
lingual and
masticatory muscles
can be studied.
• Biomechanics of jaw
and facial muscle
functions can be
studied.
14. • It is used in the management of
Myofacial Pain Dysfunction
(MPDS) and its procedure is
called Auditory or Visual
electromyographic feedback,
concerning to the muscle activity,
it supplies information to the
patient.
15. • EMG is useful for identifying the results of the
therapy and judging the asymmetry of muscle
action.
• Nocturnal bruxism and jaw muscle tracking
can be monitored.
• To evaluate muscle asymmetries or possible
postural disturbances and significant muscle
fatigue.
16. Limitations
• it does involve voluntary activation of
muscle, and as such is less informative in
patients unwilling or unable to cooperate,
children and infants, and in individuals with
paralysis
18. INTRODUCTION
• Rotary instruments complete different
functions in the cutting, polishing and
finishing of tooth structure and the restoration
process.
21. Dental Handpiece
• Most frequently used piece of machinery in
dentistry. The handpiece provides the power to
a rotary instrument that completes the actual
cutting or polishing of tooth structure and
castings.
22. Low Speed Handpiece
• Design
Straight in appearance
Standard length
Speed ranges from 10,000 to
30,000 rotations per minute
Operates the rotary instrument
in either a forward or
backward movement
23. Uses of the low speed handpiece
o Intraoral
Removal of soft decay
and fine finishing of a
cavity preparation.
Finishing and polishing
of restorations
Coronal polishing and
removal of stains
24. o Extraoral
• Trimming and contouring
temporary crowns
• Trimming and relining of
removable partial and
complete dentures
• Trimming and contouring of
orthodontic appliances
25. Micromotor
• an essential component
of the dental practice
• driven by electric power
which is transmitted
through a cord to the
handpiece
Lab Type Micromotor Unit
Clinical Type Micromotor Unit
26. High Speed Handpiece
• Design
One piece unit with a slight curve
in appearance
Operates from air pressure
Operates at speeds upto 450,000
rpm
Maintains a water coolant system
Friction grip locking system for
rotary instruments
Fibre optic lighting
27. Uses of the high speed handpiece
• Removes decay
• Removes an old or faulty
restoration
• Reduces the crown portion of the
tooth for the preparation of a
crown or bridge
• Prepares the outline and retention
grooves for a new restoration
• Finishes or polishes a restoration
• Sections a tooth during surgery
29. • It is a device enabling us to embed the
implants into the bone
Almost every part of the dispenser can be
sterilized
Physiodispenser: Physio means ‘Natural’ and
Dispenser means an ‘Automatic machine’ or
‘container’
30. Indications
• It is one of the keynote instrument for implant
surgery to prevent the bone necrosis and to
achieve better prognosis
• Root canal treatment in endodontics
• General dentistry – removal of carious dentin
31. Rationale
• TEPMPERATURE
Normal temperature of bone (40 – 45 degree C)
controlled by liquid coolant
• SPEED
Speed control for implant must be from 300-800 rpm.
It has motor capable of running at different speeds
• TORQUE
For better implant placement torque should be
between 25N.cm and 35 N.cm
32. PARTS
Control unit-FRONT
PANEL:
• Display panel
• LCD- information
• rotater holder-irrigation
tube
• push button-rotation
holder open/close
• gear ratio button
coolant button
speed button
memory button
torque button
program button
motor connector
forward/reverse button
optic button
33. • BACK SIDE PANEL:
• Foot control connector
• Label-specification
• Power cord connector
• Fuse box
• power switch(on/off)
34. FOOT CONTROL
• Foot hanger
• Coolant button
• Program change button( 10
programs)
• F/R change button- changes the
direction
• Foot pedal-micro motor speed
control
• Foot control connector
36. • Light Amplification by
Stimulated Emission of
Radiation
• Term coined by GORDON
GOULD ,1957
• Father of laser: Albert
Einstein
• Laser light is a man-made
single photon wavelength
VISIBLE LIGHT
LASER LIGHT
37. Why Lasers In Prosthodontics. . ??
• Prosthodontics takes all concepts of
dentistry and integrates effective
comprehensive treatment planning
• It include a wide variety of patients
seeking a diverse range of care:
Fearful patients
Patients with complex medical
histories
Patient allergic to anaesthetics
Lasers have become an integral
part of treatment for these
patients
39. Types Of Lasers
• Carbon dioxide Laser: wavelength has a very
high affinity for water, resulting in rapid soft
tissue removal and hemostasis.
• Advantages : highest absorbance of any laser
• Disadvantages : relative large size and high
cost and hard tissue destructive interactions
40. Neodymium Yttrium Aluminum Garnet Laser
highly absorbed by the pigmented tissue, making it a
very effective surgical laser for cutting and
coagulating dental soft tissues, with good
hemostasis
Erbium Laser : have a high affinity for
hydroxyapatite.
it is the laser of choice for treatment of dental hard
tissues.
Diode Laser : diode wavelengths are absorbed
primarily by tissue pigment (melanin) and
hemoglobin.
41. LASERS ON BASIS OF
APPLICATION IN DENTISTRY
• SOFT TISSUE LASERS
• HARD TISSUE LASERS
42. SOFT TISSUE LASERS
• No suturing
• Little or No bleeding
• Painless
• Quicker
• Atraumatic
43. HARD TISSUE LASERS
• Quicker
• More accurate
• More comfortable
• Better results
45. FIXED PROSTHETICS/ESTHETICS
• Soft tissue management around abutments
• Crown lengthening
• Osseous crown lengthening
• Troughing
• Formation of ovate pontic sites
• Modification of soft tissue around laminates
46. SOFT TISSUE MANAGEMENT
AROUND ABUTMENTS
• ARGON laser provide
excellent Hemostasis
and Coagulation
• Gingival Retraction for
making impression
during a crown and
bridge procedure
becomes easy
48. LASER TROUGHING
• A trough is created around a
tooth before impression
making using Nd:YAG laser.
• This can entirely replace the
need for retraction cord,
electro cautery, and the use of
haemostatic agents.
49. FORMATION OF OVATE PONTIC SITES
• Two most common causes of unsuitable
pontic site:
• Insufficient compression of alveolar
plates after an extraction
• Non replacement of a fractured alveolar
plate.
• Unsuitable pontic site results in un
esthetic and non self cleansing pontic
design.
• For favorable pontic design laser re-
contouring of soft and bony tissue may
be needed
POST OP
PRE OP
50. MODIFICATION OF SOFT TISSUE
AROUND LAMINATES
• The removal and re-
contouring of
gingival
• tissues around
laminates can be
easily
• accomplished with
the Argon laser
52. TUBEROSITY REDUCTION
• The most common
reason for enlarged
tuberosity usually is soft
tissue hyperplasia
• It affects stability of
prosthesis
• Surplus soft tissue
should be excised using
soft tissue lasers
53. TORUS REDUCTION
• Tori and exostoses are formed mainly
of compact bone.
• They may cause ulceration of oral
mucosa.
• They may also interfere with lingual
bars or flanges of mandibular
prostheses.
• Soft tissue lasers may be use to expose
the exostoses and
• Erbium lasers may be use for the
osseous reduction.
54. SOFT TISSUE LESIONS
Epulis fissurata, Denture stomatitis
• Persistent trauma from a sharp
denture flange
• Over compression of the
posterior dam area
• The lesion can be excised with
any of the soft tissue lasers and
the tissue allowed to re
epithelialize.
55. RESIDUAL RIDGE MODIFICATION
• For proper retention, stability and support for
the prosthesis, residual ridge modification is
done with lasers, in pre prosthetic preparation
phase for
Under cuts
Flabby tissue
57. SECOND STAGE UNCOVERING
• Following the placement of
implant and its Osseo-
integration, Er:YAG laser can
be used to uncover implants
ADVANTAGES OVER
CONVENTIONAL SURGERY
Little blood contamination
(haemostatic effects)
Minimal tissue shrinkage
Eliminate trauma to the tissues
during flap reflection
Impressions can be obtained at
the same appointment
58. IMPLANT SITE PREPARTION
• Lasers can be used for the placement of mini
implants especially in patients with potential
bleeding problems, to provide essentially
bloodless surgery in the bone
59. PERI-IMPLANTITIS
• Lasers can be used to repair ailing implants
by decontaminating their surfaces with laser
energy.
• Lasers can also be used to remove inflamed
granulation tissue around an already
osseointegrated implant.
• Diode, CO2 & Er:YAG lasers can be used
for this purpose.
61. MAXILLOFACIAL PROSTHESIS
• Topologic data of the patient’s
deformity is acquired using
laser surface digitizing, the
procedure is called Laser
Holography Imaging
• Lasers aid in creating a visually
realistic prosthesis that can
provide an illusion of normal
appearance.
62. Laser welding
• An attractive alternative
method to join dental casting
alloys such as broken clasp
• Advantages over
Conventional Soldering
No need for investment and
soldering alloy
Working time is decreased
Easy to operate
Minimal heat damage to
denture base resin
63. • Ultraviolet (helium-cadmium) laser-
initiated polymerization of liquid resin in
a chamber, to create surgical templates
for implant surgery and major
reconstructive oral surgery
64. • Laser scanning of casts
can be linked to
computerized milling
equipment for
fabrication of
restorations from
porcelain and other
materials.
65. References
• Harald O. Heymann, Andre V. Ritter, Edward J.
Swift; Sturdevant’s Art and Science of
Operative dentistry 5th edition
• Nisha Garg ;Text Book of Operative Dentistry
3rd edition
• Ankit Gupta,Akanksha Gupta,Luv Agarwal;
Electromyography and its role in dentistry;
Indian Journal of Clinical and Experimental
Dermatology, October-December
2016;2(4):132-136
66. • Chung How Kau,Stephen Richmond,Angela Incrapera,Jeryl
English,James Jiong Xia; Three-dimensional surface acquisition
systems for the study of facial morphology and their application to
maxillofacial surgery; THE INTERNATIONAL JOURNAL OF MEDICAL
ROBOTICS AND COMPUTER ASSISTED SURGERYInt J Med Robotics
Comput Assist Surg 2007
• Mahmoud Ellarousi Elbashti1, Amel Mohamed Aswehlee1,
Abdulhakim Zaggut2, Mariko Hattori1, Yuka Sumita1, Hisashi
Taniguchi1
THE ROLE OF DIGITAL TECHNOLOGY IN OVERSEAS MAXILLOFACIAL
PROSTHETIC COLLABORATION: A MODEL OF FUTURE
COLLABORATION
1) Department of Maxillofacial Prosthetics, Graduate School, Tokyo
Medical and Dental University (TMDU),Tokyo, Japan.
2) Blizard Institute, Barts and The London School of Medicine and
Dentistry, Queen Mary University of London, London, United
Kingdom.
