fluid control and soft tissue management in prosthodontics
TRANSCRIPT
Fluid control & Soft tissue management
Fluid control and
soft tissue
management
Soft tissue
displacement
Fluid controlMechanical
Chemical
Non surgical
Surgical
Recent advances
Why do we need fluid control?
Dry and clean operating field
Access and visibility
Sources of moisture in clinical environment
Saliva
• Salivary glands-parotid, submandibular, sublingual
The mean flow rate (+/- SD) of unstimulated saliva was 0.26 +/- 0.16 ml/min and that of saliva while chewing six different foods was 3.6 +/- 0.8 ml/min.
Blood
Inflamed gingival tissues/Iatrogenic damage
Water/dental materials
Rotary instruments, triplex syringe, etchants, irrigant
solutions
On a average a high speed rotatory cutting instrument
is 30 mL per minute
Gingival crevicular fluid
0.05 to 0.20 µL per minute
How is moisture control
important?
i. Patient related factors
Provides comfort.
Protects from swallowing or aspirating foreign bodies.
ii. Task/technique being performed
Dental materials are moisture sensitive, success of
adhesion and physical properties relies on a dry field.
iii. 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.
Methods of fluid control
• Mechanical
• Chemical
• Others
Mechanical methods
• Rubber dam
• Suction devices
• High volume vacuum
• Saliva ejector
• Svedopter
• Cotton rolls
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
Contraindication
Should not be used with poly-vinylsiloxane
interferes with polymerization
Patients allergic to latex
Advantages
Isolate one/more teeth
Eliminates saliva from operating site
Retracts soft tissue
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
Rubber dam set
Rubber dam
Rubber dam punch
Rubber dam clamps
Rubber dam clamp forceps
Rubber dam frame/holder
High volume vacuum
Powerful suction device, use of 10mm diameter HVE tips, and a properly functioning suction pump set to evacuate one liter per minute of fluid
Uses
Apparatus also removes small operatory debris
Excellent lip retractor
Disadvantages
Cannot be used for impression &
cementation procedure
Data comparing aerosols present during air abrasion cutting
(a.a.) with and without use of HVE and the added effect of a
ceiling mounted air purifier (Phantom) used on different
settings in an 8x10 foot operatory with an 8-foot ceiling. The
figure shows a 95 percent reduction in aerosols due to use of
HVE alone when adjusted at optimal velocity and positioned
close to the operating site during a.a use
Saliva ejector
• Low volume suction devices
• 300 ml/ min is the suction rate
• Adjunct to high volume vacuum/ rubber dam/cotton
rolls
Uses
Removes saliva from the floor of mouth
Removes water slowly
Suction tips/ saliva ejectors
Disposable saliva ejectors
- Transparent [ plastic]
- Multi coloured [ plastic]
- Hygoformic saliva ejector
- Mirror vac
- Lingua fix
- Steel
- Saliva ejector with tongue guards
Reusable saliva ejectors
Svedopter
• Metal saliva ejector with a tongue retractor
• Used for mandibular arch
• Most effective when patient is in a nearly upright
position.
Commonest and cheap
Preparation in maxillary arch in mandibular arch
Cotton rolls
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
Different types of cotton rolls
Wrapped
Braided
Cotton roll holder
Holds cotton rolls in place
Advantages
• Cheek and tongue are slightly
retracted
• Enhances visibility
Absorbents
Useful for short period of isolation
Alternatives when rubber dam application is impractical
Retracts cheek & provide absorbency
Different absorbent devices
Dry tips
Reflective shields
Dry tips
[Moisture absorbing cards]
Keeps parotid gland in check for 15 minute
Absorbs more moisture compared to cotton rolls
Reflective shields
Mirror-like reflective film allows illumination
Checks saliva control for parotid gland
Ideal for sealant and dental hygiene procedures
Chemical methods of fluid control
Administer for patient with excessive salivation
Anti- sialagogues
Local anesthetics
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
Contraindication of anti-sialogogues
Methantheline and propanthelin contraindication
Hypersensitivity to drugs
Glaucoma
Asthma
Congestive heart failure
Obstructive condition of GI tracts or urinary tracts
Clonidine hydrochloride
• Its an anti hypertensive drug hence should be
given cautiously
• Causes drowsiness
Gingival retraction
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.
Need of gingival displacement
• For accurate impressions in case of finish line at or
below the gingival sulcus.
• For restoration of cervical lesions
Classification of gingival tissue displacement
Non-surgical Surgical
Mechanical Mechano-chemical
Non surgical gingival
retraction
Mechanical methods
Retraction crown/sleeve
Mechanical retractor
Retraction cord
Mechano- chemical
Retraction cord with hemostatic
Retraction paste with hemostatic
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
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
Anatomic compression cap
Anatomic compression caps placed on patient’ s
teeth
Instruct the patient to bite on it
Advantages of compression cap
• Stops bleeding due to compression
• Opens the sulcus wide
• Ensures clean , dry area with well defined
gingival margin
Modified impression
techniques
Copper band impressions
Means of carrying the impression material and a
mechanism for gingival retraction.
Gingival margin are crimped to adapt to gingival contour
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
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
Matrices and wedges
Placed inter proximally
Uses
Depresses gingiva
Matrices with gingival extension provides
displace gingival tissue
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
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
Mechano chemical
method
Gingival retraction cords
Gingival retraction cord is a tapered diameter cordthat can be wrapped several times about a tooththat causes flared gingival crevice.
Plain cord provides mechanical retraction
Gingival retraction using chemically impregnated
retraction cord is a mechanico-chemical method of
displacement
Classification of retraction cords
Depending on the configuration
Twisted
Knitted
Braided
Depending on surface finish
Wax
Unwaxed
Depending on the chemical treatment
Plain
Impregnated
Depending on number strands
Single
Double-string
Depending on the thickness (color coded)
Black - 000
Yellow - 00
Purple - 0
Blue - 1
Green - 2
Red - 3
Desirable properties of retraction cord
• Dark color maximizes contrast with tooth & tissue
• Absorbent – can take liquid medicament
• Available in different diameters
Twisted gingival retraction cords
Allow the dentist to customize the cord as
individual strands can be removed
Knitted gingival retraction cord
• Interlocking loops
• Longitudinally elastic
• Transversely resilient
Braided gingival retraction cord
Firm
Flexible
Multistrand
Indications of #000
Anterior teeth
Double packing
Substitute for black silk
suture as lower cord in
the "two-cord" technique
Indications of #00
• Preparing and cementing
veneers
• Restorative procedures
dealing with thin, friable
tissues
Indications of #0
• Lower anteriors
• When luting near gingival and
subgingival veneers
• Class III, IV and V restorations
•
• Second cord for "two-cord"
technique
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
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
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
Instruments used for gingival retraction
• Evacuator
• Scissors
• Cotton pliers
• Mouth mirror
• Explorer
• Fisher ultrapak packer
• DE plastic filling instrument IPPA
• Cotton rolls
• Retraction cord
• Hemodent liquid
• Dappen dish
• Cotton pellets
• 2x2 gauge sponges
• Small Packer (45 degrees to handle)
• Small Packer (90 degrees to handle)
Fischer ultrapakpackers
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.
Single cord technique.
Double cord technique.
Infusion technique of gingival displacement.
Every other tooth technique.
Techniques of gingival retraction
Technique of cord placement
Retraction cord drawn
from bottle
Twisting of retraction cord
Looping of gingival cord
Cord placement from
mesial surface
Placement of cord
sub gingivally
Occasional use of extra instrument to hold
the cord and packing with other
Instrument must be angled towards
the root
Excess cord cut off in the mesial
area
Placement of distal end till it s overlapping
the mesial part of cord
Double cord technique
Indication
• Impression of multiple prepared teeth
• Impression for compromised tissue health
Procedure
Small diameter cord is placed in sulcus
Second cord soaked with hemostatic agent
Placed over small cord for 8-10 minutes
Impression made
Infusion technique
Indication Controls hemorrhage
Procedure
Retraction cord packed into the sulcus for 1-3 minutes.
Infuser used with a burnishing motion in the sulcus circumferentially 360° around the sulcus
Every other tooth technique
Anterior tooth preparation when the roots are
in proximity
Prevents collapse of gingival papilla.
Gingival displacement medicaments
• Chemicals used along with retraction cords
are classified as
Vasoconstrictors
Astringents
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)
Epinephrine
• 0.1%-8% racemic epinephrine is used
• 0.2 mg -1 mg of epinephrine per inch of cord
Contraindications of epinephrine
Cardiovascular disease
Hypertension
Diabetes
Hyperthyroidism
Known hypersensitivity to epinephrine
Patients taking
Mono-amineoxidase
Tricyclic depressants
Ganglionic blockers
Cocaine
Sympathomimetic amine
Tetrahydrozoline HCL- 0.05%
Oxymetazoline-0.05%
Phenyl epinephrine HCL-0.05%
Advantages
More acceptable pH
Astringent
Mechanism of action
Precipitation of protein
Inhibit tran-scapillary movement of plasma protein
Act as caustics at low concentration & irritants in moderate concentration.
Low cell permeability.
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
Aluminum chloride
Mechanism
Precipitate protein
Constrict blood vessels
Extract fluid from tissues
Used in 5-25% concentration for 10 min
Least irritating
Disadvantage
Interferes with the setting of PVS materials
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
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
Tannic acid
• Recommended concentration-20-100%
• Recommended time- 10 min
• Good tissue recovery
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
• 1) 20% ferric sulphate, 2) 15.5% ferric chloride, 3) 21.3% aluminiumsulphate, 4) aluminium chloride, 5) 8% epinephrine.
• Chemicals containing iron and epinephrine should not be used while managing the tissues as they cause black discolouration which is unaesthetic. Aluminium containing chemicals can safely be used in retraction cords .
Manikya Arabolu , Effect of chemicals impregnated in the retraction cords on
freshly prepared teeth, KDJ - Vol.34, No. 1, January 2011
Surgical method
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.
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
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
Shoulder prepared at the
gingival level
Torpedo diamond bur to form
chamfer finish line and removal
of epithelial sulcus
Cord placed in the troughed sulcus
Electro Surgery
Electrosurgery denotes surgical reduction of
sulcular epithelium using an electrode to produce
gingival retraction
Mechanism of action
Controlled tissue destruction.
Current flows through a small cutting electrode
a vacuum tube or a transistor to deliver a highfrequency electrical current of at least 1.0 MHz
The procedure is also called as “SurgicalDiathermy”
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
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.
Un rectified damped current
Fully rectified filtered
currentFully rectified current
Partially rectified damped
current
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.
Advantages
Clear operating area without or no bleeding
Healing by primary intension
Less tissue loss after healing
Disadvantages
Unpleasant odour.
Slight loss of crestal bone
Burn mark on the root surface
Not suitable for thin gingiva.
Contraindications
Patients with cardiac pace maker.
Patients with delayed wound healing.
Patients on steroid therapy.
In the recently irradiated areas.
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.
Grounding For patient’s safety
Circuit should be complete by using ground
electrode
Ground
Back to the unit
Tissue Goo
Composition
25% aluminum sulfate and colorants
Medium viscosity, not too thick
Matrix impression system
(Described by Levaditis)
Lasers
Indication
Controlled tissue removal before impression
making
Tissue contouring
Properties of laser depends on
Wavelength
Waveform
Types of lasers
Neodymium: yttrium-aluminium-garnet
Erbium: yttrium- aluminum-garnet
Advantages
Advantage
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
Disadvantage
Overuse causes shrinkage of tissue and also results in exposure of crown margin
• Introduced by Satalec Pierre Rolland
• Cordless gingival retraction (SDS/Kerr Company)
Composition Aluminum chloride-15% astringent & hemostatic
agent
Kaolin
Excipients
Expasyl
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
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.
Disadvantages
Expensive
Effective under limited conditions.
Disposable metal dispenser tips are too large
causes difficulty to express
Thickness makes it difficult to express
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
Inclined to be near the
edge of the marginal
gingiva
Tip of canula Pushed against the
tooth surface
Placement of metal dispenser
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
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
Components of magic foam
• Foam
• Cartridges
• Mixing and intraoral tips
• Comprecaps
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
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
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
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
Merocel strips
• Marco Ferrari et al in 1996 found Merocel
• Synthetic material that is biocompatible polymer
(hydroxylate polyvinyl acetate)
Mechanism of action
• Expands by absorption of oral fluids and exerts
pressure on surrounding tissue
Method
About 2 mm of merocel retraction strip
Provisional crown inserted
Maintain pressure on crown for 10-15 min
Advantages
Easily shaped and adapted around tooth
Highly effective in absorption of oral fluids
Chemically pure- no post surgical complications
Non abrasive
• 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)
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
Traxodent
• Syringe-dispensed 15% aluminum chloride,hemostatic paste
• Ergonomic syringe
• Easy to use
• Disposable and flexible tips
• Each syringe can be repacked for maximum freshness
• Paste with a malleable consistency
Gingival displacement in digital impressions
15% aluminum chloride in an injectable matrix
Cords avoided to prevent artifacts on digital
impression
Retraction Capsule
• Astringent retraction paste supplied in a single-use
capsule
• The retraction paste contains 15% aluminum chloride
and can be used alone or in conjunction with retraction
cord for all indications requiring temporary deflection of
marginal gingival
Aim : to investigate the pressures generated by 4 different cordless
gingival displacement materials.
A chamber with a dimension of 5x5x2 mm was made from Type IV stone
and silicone material to simulate a rigid and elastic environment. A
pressure gauge was embedded into the wall of the chamber
The pressure generated by cordless systems is more than 10 times less
than with displacement cord, and this could result in inadequate
displacement
The median post injection pressures generated by Expasyl (142.2 kPa)
and Expasyl New (127.6 kPa)
3M ESPE Astringent Retraction Paste (58.8 kPa) and Magic Foam Cord
(32.8 kPa).
Bennani .V etal Comparison of pressure generated by cordless gingival displacement
materials J Prosthet Dent 2014;112:163-167
Gingival retraction in implants
Indicated only in rare situations
• Fabrication of custom abutment
Only injectable matrix technique used
Chang YSM etal Effect of a cordless retraction paste material on implant surfaces:
an in vitro study,Braz Oral Res. 2011 Nov-Dec;25(6):492-9
G-Cuff
• G-Cuff Non-Invasive Tissue management
• Provides immediate tissue displacement for transfer
emergence profile modeling as a recipient for the resin
• For clean cementation as a cement barrier
Polymerization time compatibility index of polyvinyl siloxane
impression materials
The study comprised 10 gingival displacement agents
5 conventional astringents:
(10%, 20%, and 25% aluminum chloride, 25% aluminum sulfate,15.5% ferric sulfate)
5 experimental adrenergics:
(0.1% and 0.01% HCl-epinephrine, 0.05% HCl-tetrahydrozoline, 0.05% HCl-
oxymetazoline, and 10% HCl-phenylephrine).
It is important to avoid or minimize the direct contact of chemical displacement
agents with PVS during gingival displacement and impression procedures.
15.5% ferric sulfate from CDA group and 0.01% HCl-epinephrine and 0.05% HCl
tetrahydrozoline from the EDA group were identified in this study as optimal under
clinical conditions.
Nowakowska et al, Polymerization time compatibility index of polyvinyl siloxane
impression materials with conventional and experimental gingival margin
displacement agents J Prosthet Dent 2014;112:168-175)
References
Shillingburg HT; Fundamentals of FixedProsthodontics; 2012; 4th edition ; Quintessencepublications; USA; pp: 257-279
Rosenstiel SF; Contemporary FixedProsthodontics; 2014; 4th edition; India; pp: 431-465
Livaditis et al, Comparison of the new matrixsystem with traditional fixed prosthodonticimpression procedures, J Prosthet Dent1998;79:200-7
Shah M J et al; Gingival retraction methods in fixedprosthodontics –A systematic review, Journal of dentalsciences;2008, Vol 3(1):4-10
Thomas MS et al, Nonsurgical gingival displacement inrestorative dentistry, June 2011, Vol32(5),27-39
Shivashakthy M, Comparative study on the efficacy ofgingival retraction using polyvinyl acetate strips andconventional retraction cord - An in vivo study , Journalof clinical and diagnostic research, 2013 Oct Vol-7(10):8-11
Priyanka Bawane, Library dissertation, Fluid controland soft tissue management