5. How is moisture control
important?
i. Patient related factors
Provides comfort.
Protects from swallowing or aspirating foreign
bodies.
6. ii. Operator related factors
Infection control to minimise aerosol production.
Increased accessibility to operative site
Improves visibility of the working field
Less fogging of the dental mirror.
Prevents contamination.
7. iii. Task/technique being performed
Dental materials are moisture sensitive, success
of adhesion and physical properties relies on a
dry field.
11. Rubber dam
Introduced by S C Barnum 1864
Uses
For core build up, pattern fabrication
Impression making of inlays and onlays
Removal of old restoration and caries
For cementation
14. Disadvantages
Time consuming and patients objection
Unusual tooth shapes or positions that cause
inadequate clamp placement
Partially erupted teeth
Broken down teeth
Patients suffering from asthma
15. Rubber dam set
Rubber dam
Rubber dam punch
Rubber dam clamps
Rubber dam clamp forceps
Rubber dam frame/holder
16. High volume vacuum
Powerful suction device
Uses
Apparatus also removes small operatory debris
Excellent lip retractor
Disadvantages
Cannot be used for impression & cementation
procedure
17. Saliva ejector
• Low volume suction devices
• Adjunct to high volume vacuum/ rubber dam/cotton
rolls
Uses
Removes saliva from the floor of mouth
Removes water slowly
23. Controls small amounts of moisture and retracts
cheek and tongue
Keeps its shape and does not fall apart when full
of saliva
Provides acceptable dryness for procedures
Cementation
Impression making
Uses
28. Dry tips
[Moisture absorbing cards]
Keeps parotid gland in check for 15 minute
Absorbs more moisture compared to cotton rolls
29. Reflective shields
Mirror-like reflective film allows illumination
Checks saliva control for parotid gland
Ideal for sealant and dental hygiene procedures
30. Chemical methods of fluid control
Administer for patient with excessive salivation
Anti- sialagogues
Local anesthetics
31. Anti sialagogues
• Gastrointestinal anti cholinergic drugs that inhibit action
of myo-epithelial cells of salivary gland
Common drugs
• Bromide (Banthine) 50 mg 1 hr before
procedure
• Propantheline bromide (Pro-Banthine) 15mg 1
hr before procedure
• Clonidine hydrochloride (Antihypertensive)
0.2mg 1 hr before procedure
• Atropine 1 tablet of 0.4mg per day
32. Contraindications of anti-sialogogues
Methantheline and propanthelin contraindication
Hypersensitivity to drugs
Glaucoma
Asthma
Congestive heart failure
Obstructive condition of GI tracts or urinary tracts
35. Definition
• Gingival Retraction is the deflection of the marginal
gingiva away from a tooth.
• Gingival retraction is a process of exposing margins
when making impression of prepared teeth.
36. Need of gingival displacement??
• For accurate impressions in case of finish line at or
below the gingival sulcus.
• For restoration of cervical lesions
42. Retraction crown /sleeve
Temporary crown adapted to the finish line
Excess of temporary material lined on the finish line
Crown placed on prepared tooth
Excess material is removed
43. Disadvantages of retraction crown/sleeve
• Recession of gingiva in case it is placed for more
than 12 hours
• Delayed impression
• Cervical region of teeth becomes sensitive and
susceptible to caries
45. Advantages of compression cap
• Stops bleeding due to compression
• Opens the sulcus wide
• Ensures clean , dry area with well defined
gingival margin
53. Temporary acrylic resin coping constructed
Tray adhesive applied
Filled with elastomeric impression material and reseated
Tissue displacement occurs
Full arch impression made
Temporary acrylic coping
54. Gingival protector
• It has a crescent shaped tip on an adjustable ball
joint attached to a metal handle
Uses
Veneer preparation
Finishing porcelain/resin
Sub gingival caries
Check fitting of margins of crown
55. Matrices and wedges
Placed inter proximally
Uses
Depresses gingiva
Matrices with gingival extension provides displace
gingival tissue
56. Rubber dam
• Heavy and extra heavy rubber dams were used
• Retraction is done by rubber dam and clamps
(No. 212 cervical retainer)
• Produced retraction by compression
57. Advantages
Control of seepage and hemorrhage.
Ease of application.
Disadvantages
Full arch models cannot be made.
Severe cervical extension preparations.
Cannot be used with polyvinyl-siloxane
impression materials
59. Gingival retraction cords
Gingival retraction cord is a tapered diameter cord
that can be wrapped several times about a tooth
that causes flared gingival crevice.
Plain cord provides mechanical retraction
Gingival retraction using chemically impregnated
retraction cord is a mechanico-chemical method of
displacement
60. Classification of retraction cords
Depending on the configuration
Twisted
Knitted
Braided
Depending on surface finish
Wax
Unwaxed
61. Depending on the chemical treatment
Plain
Impregnated
Depending on number strands
Single
Double-string
63. Desirable properties of retraction cord
• Dark color maximizes contrast with tooth & tissue
• Absorbent – can take liquid medicament
• Available in different diameters
64. Twisted gingival retraction cords
Allow the dentist to customize the cord as
individual strands can be removed
67. Indications of #000
Anterior teeth
Double packing
Substitute for black
silk suture as lower
cord in the "two-cord"
technique
68. Indications of #00
• Preparing and
cementing veneers
• Restorative
procedures dealing
with thin, friable
tissues
69. Indications of #0
• Lower anteriors
• When luting near gingival
and subgingival veneers
• Class III, IV and V
restorations
• Second cord for "two-cord"
technique
70. Indications of #1
• Tissue control and/or
displacement when soaked in
coagulative hemostatic
solution prior to and/or after
crown preparations
• Protective "pre-preparation"
cord on anteriors
71. Indications of #2
• Upper cord for "two-cord"
technique
• Tissue control and/or
displacement when soaked
in coagulative hemostatic
solution prior to and/or
after crown preparations
• Protective "pre-
preparation" cord on
anteriors
72. Indications of #3
• Areas that have fairly thick
gingival tissues where a
significant amount of force
is required
• Upper cord for those
desiring the "two-cord"
technique
73. Instruments used for gingival retraction
• Evacuator
• Scissors
• Cotton pliers
• Mouth mirror
• Explorer
• Fisher ultrapak packer
• DE plastic filling instrument IPPA
75. • Small Packer (45 degrees to handle)
• Small Packer (90 degrees to handle)
Fischer ultrapakpackers
76. 45 degrees
Heads at 45 degrees
Three packing sides.
Small packer for
lower anteriors and upper lateral incisors.
90 degrees
Three sided heads
One of the heads in line with shank
Second is at a right angle to the shank.
77. Single cord technique.
Double cord technique.
Infusion technique of gingival displacement.
Every other tooth technique.
Techniques of gingival retraction
92. Mechanism of action of vasoconstrictors
Physiologically restricts blood supply to the area by
three ways
Decreasing the size of the blood capillaries
Tissue fluid seepage
Consequently size of the free gingiva.
(Ex: epinephrine and norepinephrine)
96. Astringent
Mechanism of action
Precipitation of protein
Inhibit transcapillary movement of plasma protein
Act as caustics at low concentration & irritants in
moderate concentration.
Low cell permeability.
97. Alum (Potassium aluminium sulfate)
100% of alum soaked in retraction cord
Advantages
Safer and fewer systemic effects than epinephrine
Good tissue recovery
Can be placed inside the sulcus safely for 20 min
Disadvantages
0.1% of crestal bone loss
99. Ferric sub-sulfate
• Also known as monsel’s solution
• More effective than epinephrine
• Good tissue recovery
• Recommended time- 3 min
Disadvantages
Solution is messy
Corrosive and injurious to soft tissues
Stain teeth
High acidity
100. Ferric sulfate
Recommended concentration-13- 20%
Provides hemostasis on exposed connective tissue
Recommended packing time-1-3 min
Disadvantages
Modify setting reaction of polyvinyl siloxane
Stains gingival tissue yellow-brown to black
102. Drug Advantages Disadvantages
Epinephrine Good tissue displacement
Minimal tissue loss
Good hemostasis
Systemic reactions
Epinephrine syndrome
Alum Minimal tissue loss
Extended working time
Less hemostasis &
tissue displacement
Aluminum chloride Minimal tissue loss
Good hemostasis
Local tissue destruction
Ferric sulfate Compatible with aluminum
chloride
Good displacement
Non compatible with
epinephrine
Tissue discoloration
Tannic acid Good tissue response Less displacement
Minimal hemostasis
104. Rotary gingival curettage
“Gingitage” or “Denttage”
Troughing technique
Purpose is limited removal of epithelial tissue
while a chamfer finish line is being created.
Amsterdam gave the concept further developed by
Hansing and Ingraham.
105. Criteria for rotary curettage
Done on healthy and inflammation free tissue to
prevent tissue shrinkage
Absence of bleeding on probing
Sulcus depth less than 3.0 mm
Presence of adequate keratinized gingiva
106. Technique
Shoulder finish line preparation prepared at gingival
crest using flat end tapered diamond
Finish line extended apically1/2-2/3 the depth of the
sulcus by torpedo diamond
Aluminum chloride impregnated retraction cord
placed in sulcus
Cord removed after 4-8 minutes
107. Shoulder prepared at the
gingival level
Torpedo diamond bur to form
chamfer finish line and removal
of epithelial sulcus
109. Electro cautery
“Electro cautery” is used to describe
“ Electro surgery” -WRONG
Electro cautery refers to direct current
Electrons flowing in one direction
In electro cautery heated wire comes in contact
with tissue
Electro surgery uses alternating current.
Patient is included in the circuit
111. Mechanism of action
Controlled tissue destruction.
Current flows through a small cutting electrode.
Producing high current density and rapid
temperature rise .
Cells directly adjacent to the electrode are
destroyed due to this temperature increase.
112. Types of current
Fully Rectified current (modulated)
• Continuous flow of current
• Good cutting characteristics
• Enlargement of gingival sulcus
Fully Rectified current (filtered)
• Continuous current wave
• Excellent cutting characteristics
• Less injury than modulated current
113. Partially rectified current (damped)
Considerable tissue destruction.
Slow healing.
Used for spot coagulation
Un rectified current (damped)
Recurring peaks of current that rapidly
diminish.
Causes intrinsic dehydration and necrosis.
Slow and painful healing.
Not used in dental surgery.
114. Un rectified damped current
Fully rectified filtered current
Fully rectified current
Partially rectified damped current
115. Tissue considerations
Keep electrode in motion.
5-10 seconds between applications.
Patient should be properly grounded.
Tissue must be moist.
Electrode must remain free of tissue fragments.
Electrode must not touch any metallic restorations.
116. Advantages
Clear operating area without or no bleeding
.
Healing by primary intension
Less tissue loss after healing
118. Contraindications
Patients with cardiac pace maker.
Patients with delayed wound healing.
Patients on steroid therapy.
In the recently irradiated areas.
119. Technique
Anesthesia
A drop of aromatic smelling oil.
Complete seating of electrodes in handpiece.
Light pressure and quick ,deft stoke
5-10 seconds between each stroke.
120. Grounding
For patient’s safety
Circuit should be complete by using ground
electrode
Ground
Back to the unit
131. Advantages
Minimum pain and discomfort
Less fear ,anxiety and stress
Minimum or no anesthesia
No drill sounds
Less chair time
Reduced post operative complications
Minimum or no bleeding
135. Mechanism of action
• It has both mechanical and chemical action
Aluminum chloride provides- hemostasis
Viscosity of Kaolin- retracts the tissue
Recommended time of application-1-2 min
136. Advantages
Effectively achieves hemostasis.
Effectively retracts gingival tissues
Less traumatic to tissues than cord packing.
Faster than traditional cord.
Easy removal from sulcus by rinsing.
Dispenser tips can bent- improves intraoral access.
138. Precautions
Thorough cleaning is mandatory to prevent
interference in polymerization of poly vinyl siloxane
materials
Contraindications
Presence of periodontal pocket and furcation
Known allergy to aluminum chloride
139. Inclined to be near the
edge of the marginal
gingiva
Tip of canula Pushed against the
tooth surface
Placement of metal dispenser
140.
141. Magic foam
Developed by Prof Dr. Dumfahrt
Non-hemostatic gingival retraction system
(Coltène/ Whaledent)
First expanding vinyl polysiloxane material
designed for retraction of the gingival sulcus
142. Mechanism
•Expansion of silicon foam
Limitation
Limited clinical indications
Less hemostatic
No improvement in speed/quality compared
to cord
Less effective on sub gingival margin
143. Components of magic foam
• Foam
• Cartridges
• Mixing and intraoral tips
• Comprecaps
147. 60 subjects who required metal ceramic restoration
Mean vertical displacement
• Expasyl -0.72 mm
• Medicated retraction cord-0.49 mm
• Magic foam-0.38 mm
Mean gingival retraction width
• Expasyl -0.37 mm
• Medicated retraction cord- 0.29 mm
• Magic foam- 0.26 mm
Rao et al; Comparative evaluation of gingival displacement using expasyl,
magic foam cord and medicated retraction cord-An vivo study, TPDI ,January
2012, Vol.3,No.1
148. Gingitrac (Centrix co)
Mild natural astringent gel
Utilizes patient s bite pressure to push material into
sulcus and retract gingiva
Consists of
Mixing gun
Gingitrac cartridge
Gingitrac matrix cartridge
Mixing nozzle
Dispensing tips
Gingicap
152. Advantages
Less traumatic to tissues than retraction cord
Color of foam makes it easy to see during use
Easy to remove material from preparation and sulcus
Adequate working time
153. Disadvantages
Limited clinical indications
No hemostasis provided
Relatively expensive compared with retraction
cord
No improvement in speed or quality of retraction
compared with cord
Less effective on sub-gingival margins
Intraoral tips may be too large to adequately inject
material into sulcus
154. Merocel strips
• Marco Ferrari et al in 1996 found Merocel
• Synthetic material that is biocompatible polymer
(hydroxylate polyvinyl acetate)
155. Mechanism of action
• Expands by absorption of oral fluids and exerts
pressure on surrounding tissue
156. Method
About 2 mm of merocel retraction strip
Provisional crown inserted
Maintain pressure on crown for 10-15 min
157. Advantages
Easily shaped and adapted around tooth
Highly effective in absorption of oral fluids
Chemically pure- no post surgical complications
Non abrasive
158. • 14 maxillary tooth requiring complete metal ceramic
restoration
• Retraction was done using merocel and
conventional method
Mean vertical retraction of gingival cord - 2.02
Mean vertical retraction of retraction strips - 2.78
Shivashakthy M, Comparative study on the efficacy of gingival retraction
using polyvinyl acetate strips and conventional retraction cord - An in vivo
study , Journal of clinical and diagnostic research, 2013 Oct Vol-7(10)
159. Stay put retraction cord
Fine metal filament reinforced displacement cord
impregnated or non impregnated
Consist of braided retraction cord and ultrafine
copper filaments
Remains in shape and does not deform
161. Gingival displacement in digital
impressions
15% aluminum chloride in an injectable matrix
Cords avoided to prevent artifacts on digital
impression
162. Gingival retraction in implants
Indicated only in rare situations
•Fabrication of custom abutment
Only injectable matrix technique used
164. Livaditis et al, Comparison of the new matrix
system with traditional fixed prosthodontic
impression procedures, J Prosthet Dent
1998;79:200-7
Shah M J et al; Gingival retraction methods in fixed
prosthodontics –A systematic review, Journal of
dental sciences;2008, Vol 3(1):4-10
165. Thomas MS et al, Nonsurgical gingival
displacement in restorative dentistry, June 2011,
Vol32(5),27-39
• Shivashakthy M, Comparative study on the efficacy
of gingival retraction using polyvinyl acetate strips
and conventional retraction cord - An in vivo
study , Journal of clinical and diagnostic research,
2013 Oct Vol-7(10):8-11
Editor's Notes
For elastomeric impression dam must be lubricated and clamp must be removed or avoided
Can remove 150 ml of water in one min.
The Mirro-Vac Saliva Ejector Mirror combines evacuator and mirror functions into one efficient instrument.
Upper suction inlet relieves tissue grab and ensures anti-fog acrylic mirror stays clear-even under direct exhalation
coil eliminates the sharp edges and hard blunt tip which irritate soft tissue- HYGROFORMIC SALIVA TIPS
Anterior part of it rests on anterior teeth
Available in various sizes- small medium and large
Prefabricated are more compact
No. 2 cotton roll 1 ½” Long and 3/8” in diameter are most popular
braided -Made of silky yarn. Absence of chemicals .Unique wicking action .Available in size-Small- 3/4”.Medium- 1 1/2”.Large diameters- 4” and 6
wrapped
100% cotton interior.Non-woven fabric. Rolls sealed with adhesive .Starch-free- Do not stick to mucosa.Available in 1 1/2” sterile and non-sterile
These are pressed cellulose wafers covered with a reflective foil on one side. The paper side is placed against the dried buccal tissues and adheres to it.
Outlasts cotton rolls and other absorbents.
When removing absorbent cards/cellulose wafers it may be necessary to moisten them with the water gun to prevent inadvertent removal of epithelium from cheek.
In whom controlling with mechanical method is difficult.
To achieve a good marginal fit the finish line must be recorded in the impression. the gingiva must be completely displaced to make an impressionand sometimes even to permit completeion of tooth preparation or cementation. It was introduced by thomson 1941 he used moistened cotton rolls to displace gingiva.
The temproary material can be thermoplastic material or bulky cements like zinc oxide eugenol or non-eugenol containing periodontal pack
IMPRESSION CANNOT BE MADE ON THE SAME DAY AS TIME IS REQUIRED TO DISPLACE THE GINGIVA PROPERLY
Time -3-5 min
Festooned or trimmed.
Impression compound or elastomeric impression material
Internal surface relived by 1mm .A complete arch impression made over the coping
Coping becomes an integral part of the complete
arch impression.
Tip can rotate to an angle that matches the tooth s facial surface for achieving gingival fit
Hence it is known as gum compression rather than gum retraction.
Full arch models cannot be made it is used for limited no of teeth in one quadrant.
Severe cervical extension preparations – subgingival preparations are difficult
. In use, the cord, starting with its smaller end, is spirally wrapped and packed about a tooth between the tooth and surrounding gingival tissue to form a flared gingival crevice
Careful not to touch the cord other than ends to avoid contamination hold it bet forefingers and thumb
In some areas where the finish line is more coronal or the gingi.sulcus is more shallower then the cord doesn’t stay in its placethen we can take the help of other packer and move forward
Small cord is left in the sulcus during impression making second cord placed in the sulcus above small diameter cord
Studies have shown local tissue destruction at a concentration of more than 10% inhibitory effect managd by thorough rinsing
Done on healthy and inflammation free tissue to prevent tissue shrinkage that occurs when diseased tissue heals
Done along with preparation of finish line.
Unrectified current also known as Oudin and TElsa
this is to inform u that this seminar is interesting
when dispensing — it has a tendency to spurt out, wasting half a
syringe.
Introduced in 1983, it consisted of 3 impression procedure with 3 viscosities
320-400 microns at the sulcular level
Neodymium: yttrium-aluminium-garnet
prefered for resection of oral soft tissue and can be used withot anesthesia.
They used quartz optical fiber
Red helium neon laser used to provide visible aiming.
glass cartridges similar in size and shape to anesthetic cartridgesA metal dispenser gun is used to express the paste through a disposable metal dispensing tip into the gingival sulcus prior to impression making or prosthesis cementation. In 1978, Van der Velden and De Vries studied the forces applied to the sulcus during various dental procedures. They observed a tearing of the epithelial attachment as soon as pressure of 1N/mm2 was applied to the marginal gingiva. This attachment was destroyed when the pressure exceeded 2.5N/mm2. The pressure applied by a retraction cord in this region is between 5 and 10N/mm2 (depending on the number of cords inserted into the sulcus). A simple periodontal probe exerts a pressure between 1 and 2N/mm2. To separate the marginal gingiva from the human tooth at a distance of 1.5 mm, it is necessary to apply a pressure of 0.1N/mm2. The conclusion of these studies was that gingival retraction should be accomplished under a pressure of between 0.1 and 1N/mm2 to avoid tearing of the epithelial attachment.