2012 Gingival Retraction

7/27/2019 2012 Gingival Retraction

1/16

GINGIVALRETRACTION


2/16

GIVGIVAL RETRACTION

Done after a tooth is prepared for a crown to ensure that an

impression with clear margins can be obtained No hemmorage present

All hard & soft tissue to be reproduced must be clean & dry

Ideal margins are supragingival

Many may be subgingival

Tissue displaced vertically- to expose margin

Tissue retracted horizontally- allow room for impression material


3/16

GINGIVAL RETRACTION

Retraction- can be done chemically, mechanically,

surgically, or combination

Retraction cord- available in variety of sizes,

configurations, and chemical treatments

Comes in dispensing package for easy use May be twisted, braided, or woven to hold its shape


4/16

TYPES OF RETRACTION

Two types of retraction

1. Mechanical

Non-impregnated to displace tissue to

allow access to margin

2. Chemical

Impregnated with chemical agent

added


5/16

MECHANICAL Retraction cord placed in sulcus of

healthy, inflamed-free gingiva

Cotton left in place 10-15 minutes

Too deep- crevice open at bottom,narrow at top (material will fracture at

edge of prep)

Too shallow- space inadequate to allow

accurate reproduction of the margin of

the prep

Proper position- 1-3 mm into the v-

shaped crevice

MECHANICAL RETRACTION


6/16

MECHANICAL RETRACTION

Another way to lengthen atemporary crown form to cause

tissue displacement and take the

impression at a later date

Dental dam clamp and rubberdam to displace tissue

Clamp & dam placed and

removed prior to taking final

impression

Both these techniques may cause

tissue to bleed and impression

distortion


7/16

CHEMICAL RETRACTION

May be done prior toplacement of the cord

By impregnating cord,

then placing it, or both

Newer way- use a

topical hemostatic

solution astringent

with dento-infusiontubes and plastic lure

lock syringe


8/16

NEWER CHEMICAL RETRACTION PROCEDURE

1. Place solution using a disposable metal tip bent to thedesired area

2. Blood & solution merge together and are washed

away with air/water syringe

3. Temporary seal left that does not allow any seepage

4. Retraction cord of interwoven cotton with or without

solution placed vertically to expose prepared margin

5. This packing allows for horizontal retraction


9/16

6. Cord could also have aluminum chloride or

astringent of aluminum salts for chemicalretraction (this technique causes ischemia)

Epinephrine

An astringent and vasoconstrictor

Provides hemostasis and shrinks tissues

constricting the blood vessels

Causes tachycardia

Contraindicated for patient with heart disease,diabetes, hyperthyroidism



10/16


7. Dual astringent and hemostatic action of aluminum

chloride plus kaolin clay Controls bleeding

Absorbs fluids to ensure a clean, dry sulcus


11/16

SURGICAL RETRACTION

Use surgical knife or electrosurgery to remove tissue

and preparation

Area may bleed and cause additional treatment

Electrosurgery unit- cauterizes tissues as it removesthem (no bleeding)

Must have soft tissue anesthesia Not used with patients receiving radiation therapy,

have cardiac pacemakers, or slow healing diseases

Non-metal HVE tip during surgery reduces odor if

placed near surgical site Rinse sulcus with hydrogen rinse


12/16

ELECTROSURGERY


13/16

PLACING AND REMOVING RETRACTION CORD

EQUIPMENT NEEDED HVE tip and air/water syringe tip Scissors

Hemostat

Retraction cord

Retraction cord placement instrument or plastic instrument

Cotton rolls 2x2 gauze sponges


14/16

STEPS FOR PLACING AND REMOVING

RETRACTION CORD

1. Tooth prepared for crown

2. Rinse and dry area

3. Place cotton rolls, dry area

4. Dentist selects retraction cord5. Length determined by

circumference of toothanterior tooth

Wrap around small finger Posterior tooth: larger finger

6. Cut cord to appropriate length


15/16


RETRACTION CORD

7. Twist cord ends to compress fibers together

8. Cord is looped and placed in a hemostat orcotton pliers

9. Cord looped around margin of prepared toothand tightened slightly

10. Release ends of hemostat or cotton pliersleaving cord in sulcus


16/16


RETRACTION CORD CONTD

11. Pack retraction cord into position with packing instrument orplastic instrument

12. Pack cord around cervical area, apical to preparation

13. Pack cord around tooth and overlap on facial surface

14. Leave tip of cord showing out of sulcus in order to remove justprior to taking impression

15. Placement time

5 minutes left in place-for chemical retraction

10-15 minutes- for mechanical retraction

16. Remove end of cord in a circular motion prior to impressionbeing placed

Documents

2012 Gingival Retraction