ISOLATION & FLUID ISOLATION & FLUID CONTROL IN FPDCONTROL IN FPD

Dr. Imtiyaz A Magray Dr. Imtiyaz A Magray JR-1,Dept. Of Prosthodontics, Crown & Bridge, ImplantologyJR-1,Dept. Of Prosthodontics, Crown & Bridge, Implantology

RDCHRDCH

Contents :- GOALS OF ISOLATION. SOURCE OF MOISTURE WHY MOISTURE CONTROL METHODS OF ISOLATION.- DIRECT METHOD- INDIRECT METHOD SUMMARY CONCLUSION REFERENCES

GOALS OF ISOLATION

Maintaining DRY CLEAN ENVIRONMENT.

Improves ACCESS AND VISIBILITY.

Improves the PROPERTIES OF DENTAL MATERIALS.

PROTECTING the adjacent hard and soft tissues.

Improves the OPERATING EFFICIENCY.

Sources of moisture in the clinical environment:

Saliva: - from salivary glands. (parotid, submandibular, sublingual)

Blood: - inflamed gingival tissues. - iatrogenic damage.

Gingival crevicular fluid: -inflamed gingival tissues.

Water/dental materials:

- from rotary instruments.

- water from triplex syringe.

-materials we may use during treatment [e.g.. etchants, irrigant solutions].

Why is moisture control important?

i). Patient related factors

Comfort.

Protects patients swallowing or aspirating foreign bodies.

Protects patient soft tissues – tongue, cheeks by retracting them from operating field.

“A small round bur detached from the slow speed hand

piece was lodged in patients’ left bronchus….. The patient underwent a

thoracotomy to retrieve the bur and was away from work for a considerable time. This Case was settled for $75, 000.”

Australian Dento-Legal Review 2002 Guild Insurance pp12

ii). Operator related factors

Infection control; to minimise aerosol production. Increased accessibility to operative site, allowing

greater convenience and efficiency of operative. Procedures (e.g. patient’s “need to swallow”)

causes fewer problems. Improves visibility of the working field and

diagnosis. Less fogging of the dental mirror.

iii). Task/technique being performed:

Dental materials are moisture sensitive, success of adhesion and physical properties relies on a dry field.

METHODS OF ISOLATION

DIRECT METHODS-

RUBBER DAM. COTTON ROLLS AND CELLULOSE WAFERS. GUAZE PIECES/THROAT SHIELD. SUCTION DEVICES:

High volume evacuators. Low volume evacuators: SALIVA EJECTORS.

GINGIVAL RETRACTION CORDS. LASERS SVEDOPTER ROTARY CURETTAGE ELECTROSURGERY

INDIRECT METHODS-

COMFORTABLE POSITION OF THE PATIENT AND RELAXED SURROUNDINGS.

LOCAL ANAESTHESIA.DRUGS-

Anti- sialogogues Anti-anxiety drugs

DIRECT METHODS OF ISOLATION

RUBBER DAMRUBBER DAM

1864 S C Barnum first described rubber dam.

Isolation of one or more teeth from the oral environment.

Rubber dam eliminates saliva from the working field and also retracts soft tissues

Rubber dam set Rubber dam sheets (green, blue & black)/15cm- natural

latex Rubber dam punch- 0.5-2.5mm diameter. Rubber dam clamps- anchor dam to tooth Rubber dam clamp forceps- placement of retainer as

well as removal of retainer Rubber dam frame/holder- supports edges of RD Rubber dam stamp for marking the position of tooth Rubber dam lubricant –facilitates placing of the dam Waxed dental floss – tests interdental contacts,

prevents aspiration RD napkin- placed b/w RD and skin Scissors

Advantages:Complete, long term moisture control Maximises access and visibility

Protection for both patient and dentist

Infection control measure

Prevents accidental swallowing or aspiration of foreign bodies

Retracts soft tissues

Increases operator efficiency

Improved properties of dental materials

DISADVANTAGES :- “THE MOST TIME- CONSUMING THING ABOUT THE

RUBBER DAM IS THE TIME REQUIRED TO CONVINCE THE DENTIST TO USE IT”

Time consumption and patient objection Cannot be applied to the tooth that are not sufficiently

erupted to receive retainers. Extremely malpositioned teeth Asthmatic patients who have difficulty in breathing

through nose Allergic to latex Inappropriate retainers can impinge on the soft tissues

and traumatize it Accumulation of saliva beneath Rubber Dam

Do not use Do not use polyvinyl siloxane polyvinyl siloxane impressionimpression material if RD is being material if RD is being used - inhibit polymerizationused - inhibit polymerization

RD is mainly Indicated for RD is mainly Indicated for inlays inlays and onlaysand onlays preparations in FPD preparations in FPD

Recent advances in rubber dam isolationRecent advances in rubber dam isolation Handi Dam Insta dam Cushioning metal clamp jaws Cushees Fiber optic clamps Liquid Dam

Suction devices

HIGH-VOLUME EVACUATORS:- High-volume evacuators are

preferred for suctioning water and debris from the mouth.

The combined uses of water spray or air water spray and a high volume evacuator during cutting procedure has the following advantages-

1. A washed operating field improves access and visibility.

2. There is no dehydration of the oral tissue.

3. Quadrant dentistry facilitated.

The assistant should place the evacuator

tip in the mouth before the operator positions the hand piece and mirror.

The tip of evacuator should be placed just distal to the tooth to be prepared. So that it should not obstruct the operators access or vision.

SALIVA EJECTORS/LOW-VOLUME SALIVA EJECTORS/LOW-VOLUME EVACUATORS:-EVACUATORS:-

Saliva ejectors remove water slowly and have little capacity for picking up solids.

The saliva ejector removes saliva that collects

on the floor of the mouth. It may be used in conjunction with sponges,

cotton rolls, and the rubber dam. It should be placed in areas least likely to

interfere with the operators movements and its tip should be smooth and made of a non-irritating material.

Disposable, inexpensive plastic ejectors that may be shaped by bending with the fingers are preferable because of improved infection control.

May be used by the lone dentist.

SVEDOPTER :-SVEDOPTER :- It is a saliva ejector which not only

removes saliva but also retracts and

protects the tongue and floor of the mouth.. A mirror like vertical blade is attached

to the evacuator tube so that it holds the

tongue away from the field of operation. Several sizes of vertical blades are

supplied by the manufacturer.

It is designed so that the

vacuum evacuator tube passes anterior to the chin and mandibular anterior teeth, over the incisal edges of mandibular anterior teeth and down to the floor of the mouth

An adjustable horizontal chin blade is attached to the evacuation tube so that it will clamp under the chin to hold the apparatus in place.

Disadvantage

1. Less lingual access of mandibular teeth

2. Made of metal- bruising of soft tissue

3. If tori present- not used

4. Oversized reflector- triggers gag reflex

HYGOFORMIC SALIVA EJECTOR:-HYGOFORMIC SALIVA EJECTOR:- This coiled saliva ejector is used in the same way as

the Svedopter, but it does not have a reflective blade. More comfortable and less traumatic to lingual tissues

than the Svedopter. It must be reformed before use. It is also used in conjunction with absorbent cotton for

maximum effectiveness.

MOUTH PROPA potential aid for preparation on posterior teeth The ideal characteristics of a mouth prop are-

It should be adaptable and easily adjustable Provide proper mouth opening   It should be capable of being easily positioned with no

patient discomfort. It should be stable once it is applied. It should be easily removable. It should be either sterilizable or disposable. It is placed on the side opposite to the treatment site and

positioned posteriorly between the maxillary and mandibular teeth.

GINGIVAL RETRACTION

The deflection of the marginal gingiva away from a tooth. (GPT-8)

NEED FOR GINGIVAL RETRACTIONNEED FOR GINGIVAL RETRACTION Allow access for the impression material

beyond the abutment margins Space for the impression material to be

sufficiently thick Expose the prepared tooth surfaces Permit the completion of tooth preparation

Cementation of the laboratory manufactured restorations

Critical factor – gingival tissues are in optimum state of health before making impression

Optimum position of the margin – 0.5mm from free gingival margin, 3-4mm from crest of alveolar ridge, natural scalloped form of the attachment

Mechanical Chemical – haemostatic medicament Surgical – rotatory gingival curettage and

electro surgery Combination of three Lasers

Copper band

Indicated- when many teeth are prepared, when preparation are not extended far off gingivally, periodontally weakened teeth.

Impression material- modeling compound, heavy body elastomer.

May cause recession.

Retraction cord Isolation and retraction

Moistened with a non-caustic haemostatic agent and is placed in the gingival sulcus to control Sulcular seepage or hemorrhage or both.

Access and visibility

Restrict excess restorative material

Produces lateral displacement of free Gingiva without blanching it.

Twisted cords Knitted cords Braided cords

Selection of which design of cord to use depends on operator`s preference

Braided cordsBraided cords- Easier to place- Impregnated with the astringent

or even covered with the gel of that astringent

- If wrapped around ultrathin copper wire- more stable

- Modified braided cord- less memory- more precise placement- minimal soft tissue damage- superior absorption- no tear during placement

Braided and twisted cords use serrated and smooth cord packer.

71µg of epinephrine absorbed by 2.5cm of retraction cord

Knitted cordsKnitted cords- Easy placement- Minimum fraying at the cutting

ends- Expand when wet- Open sulcus greater then the

diameter of the cord.

Knitted uses smooth cord packer

Dispenser with 183cm cord are available

Difference in fiber orientation between

knitted and braided cords. Strands of braided are more parallel than

the knitted ones along long axis of cord. Composed of ultrafine copper filament

bounded with nylon

GINGIVAL RETRACTION CORDS AND CAPSGINGIVAL RETRACTION CORDS AND CAPS

s.no Product Name (Company) Sizes available Dispenser type Medicated

1. Hemodent Retraction Cord (Premier Products Company

Braid: ThinMedium-ThinTwist:3, 9

Not medicated

2. CrownPak (GingiPak) 4-ply Kutter Kap Epinephrine HCl (Racemic epinephrine)

3 GingiAidZ-Twist (GingiPak) 0, 1, 2, 3 Kutter Kap Aluminum Sulfate

4 Gingiplain Soft (GingiPak) 1, 2, 3 Kutter Kap Non-impregnated

5 Pascord (Pascal Company, Inc) 7, 8, 9, 10 Aluminum Sulfate

6 Racord (Pascal Company, Inc) 7, 8, 9, 10 Racemic Epinephrine HCl

7 Racord II (Pascal Company, Inc) 7, 8, 9, 10 Reduced Racemic Epinephrine HCl and Zinc Phenosulfonate

8 Unibraid (Van R) 0, 1, 2 Epinephrine/Alum 87 or Aluminum Potassium Sulfate

9 Sulpak (Sultan Healthcare) Small, Medium, Large

Pull 'n Cut Dispenser

Astringent – Aluminum Potassium Sulfate NF; Vasoconstrictor - 4%Racemic Epinephrine HCl; and Combination - Aluminum Potassium Sulfate and 4% Racemic Epinephrine

10 Ultrax (Sultan Healthcare) Small, Medium, Large

Pull 'n Cut Dispenser

Astringent – Aluminum Potassium Sulfate NF; Vasoconstrictor – 4% Racemic Epinephrine HCl; and Combination - Aluminum PotassiumSulfate and 4% Racemic Epinephrine

The cord can be packed with a special instrument like Fischer packing instrument or a DE plastic instrument IPPA.End and angle of the cord packer is of more concernCan be serrated or smoothDouble end instrument

Sufficient diameter for adequate

displacement Primary error is to use cord of minimal

diameter – no lateral displacement

Aluminum potassium sulphate (alum), aluminum sulphate, 20-25% aluminum chloride, 8% racemic epinephrine, 15-20% ferric sulphate

Epinephrine- systemic side effects- epinephrine syndrome (tachycardia, rapid respiration, elevated blood pressure, anxiety, postoperative depression)

Increased absorption- Increased vascular bed, amount/dose.

Patient`s endogenous epinephrine may also be secreted in reaction to stress.

GINGIVAL HEMOSTATIC AGENTS GINGIVAL HEMOSTATIC AGENTS

s. No

Product Name (Company) Material type Dispenser type Composition

1. Hemostasyl™ HaemostaticAgent (Kerr Corporation)

Gel Syringe 15% Aluminum Chloride

2. FS Haemostatic (Premier Products Company)

Solution Dropper, bottle 15.5% ferric sulfate

3. Astringedent (Ultradent) Solution Bottle 15.5% ferric sulfate

4. Hemodent (Premier Products Company)

Inquire Bottle Buffered Aluminum Chloride

Epinephrine is a direct sympathomimetic drug. Acts directly on α and/ or β adrenoreceptors. Epinephrine acts on α1+ α2 + β1 + β2Heart rate ↑

Cardiac output ↑↑

BP- systolic Diastolic Mean

↑↑↓↑↑

Blood flow skin & membrane sk. Muscle Kidney Liver coronary

↓↑↑↓↑↑↑

Bronchial muscle ↓↓

Intestinal muscle ↓↓

Blood sugar ↑↑

Bowels et al found no significant difference in

Sulcular width around teeth treated with alum and epinephrine cord. J Dent Res 1991;70:1447-

1449. Weir and Williams found no significant difference

b/w hemorrhage control by aluminum sulphate and epinephrine

J Prosthet dent 1984;51:326-329.

Shaw et al found no additional inflammation with dilute aluminum chloride but was seen with the conc. ones

Oper Dent 1980;5:138-141.

Hyperthyroidism Patients on MAO inhibitors Patients on TCA B-blockers Cocaine Diabetic Cardiovascular disorder patients

Gingival retraction cord.- retracts gingival tissues and controls GCF/small amounts of bleeding.

Techniques for gingival

displacement

Single cord technique Double cord technique Infusion method of gingival retraction

Single cord techniqueSingle cord technique

Technique of placement

For making impression of multiple prepared tooth

When tissue health is compromised When procedure delay is not possible

Small diameter cord is placed Cut the ends… so that they can exactly abut

against each other Cord is left in sulcus during impression making If cord is short, it may impregnate in impression,

that cause difficulty in pouring and trimming of the die

Place the second cord (of largest diameter) soaked in

haemostatic agent over the small diameter cord Wait for 8-10min Soak the second cord in water and remove it Make the impression with first cord still there in sulcus After making impression, soak the first in water and then

remove it

After careful preparation of cervical margin Control hemorrhage using specially designed dentoinfusor with the ferric sulphate medicament 20% ferric sulphate is preferred because it is less acidic Infuser is carried circumferentially3600 around the sulcus

Medicament is extruded from the syringe

around the sulcus Pack the knitted retraction cord soaked in

ferric sulphate Leave the cord for 1-3min Remove the cord Rinse the sulcus Make impression Ferric sulphate darkens the tissue

Teeth with root proximity- retraction cord placement may result is strangulation of gingival papilla & eventually loss of papilla

This creates unaesthetic black triangle in embrasure area

Place the retraction cord at the most distal prepared tooth

No cord is placed around the prepared tooth mesial to this tooth

Expasyl Gingi trac Magic foam cord Racegel Traxodent

Cordless gingival retraction

Expasyl- When homeostasis &

sulcus opening is required

- Has white clay (kaolin), water, aluminum chloride

- Paste is injected into sulcus with pressure of 0.1N/nm.

- Left in place for 1 min- Sulcus opening of 0.5mm

is obtained- Supplied in reusable

capsules, injection canulas, applicator.

GINGIVAL RETRACTION PASTES AND GELSGINGIVAL RETRACTION PASTES AND GELS

1. Expasyl gingival retraction paste (Kerr corp.)

Viscous paste Capsules, applicator tips, applicator g

Aluminum chloride

2. Traxodent hemodent paste(premier products company)

Paste syringe medicated

3. Gingi trac (centrix) Gel Auto mix gun delivery

Non medicated

4. Gingi trac singles(centrix) Gel syringe Medicated and astringent included

5. Magic foam cord (coltene whaledent)

PVS material syringe Not medicated

Use of LASERS for retraction

Laser systems are composed of an active medium, which may be a solid (Er,Cr:YSGG laser and Er:YAG laser) or a gas (CO2 lasers); an external power supply; an optical resonator; a cooling system; a control system; and a delivery system.

Laser energy can be delivered via an articulated arm, hollow wave guide, or an optic fiber. In the case of the Er,Cr:YSGG laser, energy is delivered to the targeted tissue via an optic fiber to a hand piece, is reflected by a mirror, and passes through a sapphire or zirconium tip.

The energy produced by the Er,Cr:YSGG

laser demonstrates good absorption by water and, to a lesser degree, hydroxyapatite.

Because all dental tissues contain water, the Er,Cr:YSGG laser is useful for many dental procedures.

Managing soft tissue using rubber-dam

clamps, scalpels, or retraction cord is effective, but each method results in postoperative discomfort.

Discomfort can be a source of anxiety in dental patients, which can cause adults to avoid regular dental care.

The use of retraction cord containing epinephrine can result in high blood levels of epinephrine, which can cause undesirable cardiovascular changes.

The use of retraction cord also can result in permanent gingival recession

By contrast, the removal of soft tissue to access caries or for gingival troughing before impressions can be performed using laser energy with little or no bleeding, minimal tissue trauma, and reduced postoperative pain.

When used to remove soft tissue, laser

energy is more precise than a clamp or a scalpel because laser energy can be delivered to the tissue in a more controlled manner. The reduction in tissue trauma results in decreased postoperative pain.

The use of an Er,Cr:YSGG laser is an effective, minimally invasive method to accomplish the goal of soft-tissue management for various operative procedures.

No postoperative discomfort compared with conventional tissue-management techniques, such as retraction clamps, retraction cord, or gingival flap reflection with a scalpel.

Patients may be more motivated to have regular dental visits if a source of dental anxiety, postoperative pain, can be reduced or eliminated.

Surgical methodsRotary curettage

Electro surgery

Gingival sulcus enlargement

Removal of edentulous cuff

Crown lengthening

Rotary curettageRotary curettage

Is a “troughing” technique - limited removal of epithelial tissue

in the sulcus while a chamfer finish line is being created in tooth

structure

- Amsterdam 1954

Also called “gingettage” used with the sub gingival placement

of restoration margins

Should always be done on healthy, inflammation free tissue to

avoid the tissue shrinkage that occurs when diseased tissue

heals

Gingettage

Electro surgery (Electro surgery (D’Arsonval 1891)D’Arsonval 1891) Indications

For the removal of irritated tissue that has proliferated over preparation finish lines

For enlargement of the gingival sulcus Control of hemorrhage to facilitates impression making

Current flows from a small cutting electrode that produces a high current density and a rapid temperature rise at its point of contact with the tissue

The cells directly adjacent to the electrode are destroyed by

this temperature increase

INDIRECT METHODS

1. Comfortable and relaxed position of the patient

2. Local Anesthesia 3. Drugs

Comfortable and relaxed position of the patient

The patient should be comfortably seated in the dental chair.

The surroundings should be pleasing and relaxing.

All these factors as well as comforting attitude of the dental staff reduce the anxiety levels of the patient and aids in reducing salivation.

Local Anesthesia

It helps in reducing the discomfort associated with the treatment in addition to controlling moisture by decreasing salivation.

Making the patient comfortable, less anxious and less sensitive to stimuli helps in producing lower salivary flow thus helping in moisture control.

Another advantage is the vasoconstriction caused by L.A. which helps in reducing hemorrhage at the operating site.

Drugs Antisialogogues : Premedication may be

indicated using an anticholinergic agent to depress salivation in patients for whom no mechanical device is effective producing a dry enough filed.

Atropine can be given half an hour before the appointment, but should be avoided in patients with ocular (glaucoma) pressure, asthma, with cardio-vascular problems, nursing mother or patients with obstructive conditions of the gastro intestinal or urinary tracts.

Usually one 50-mg tablet of Banthine or 15 mg

of Pro-Banthine taken 1 hour before the appointment will provide the necessary control.

Anti anxiety agent (Anxiolytic agents) and Sedatives : Premedication with these drugs is quite helpful in apprehensive patients. Example : Diazepam 5-10 mg before the appointment.

Because the psychological dependence on these drugs, these should be given only for short periods and to selected patients.

OTHER AIDS

COTTON ROLL AND CELLULOSE WAFERS

Cotton rolls can be manually rolled or prefabricated. Prefabricated are more compact.

They provide satisfactory dryness. Advantage of cotton roll

holders is that they may

slightly retract the check

and tongue from the teeth,

which enhances access

and visibility.

• Cellulose wafers/ Parotid shield are used in conjunction with cotton rolls, especially in the facial aspect of posterior teeth to absorb the saliva secreted by the parotid gland.

THROAT SHIELDS When rubber dam is not being used, throat shield is indicated

when there is danger of aspirating or swallowing small objects.

This is particularly important when treating teeth in the maxillary arch.

A gauze sponge [2 x 2” ( 5x 5 cm) ], unfolded and spread over the tongue and the posterior part of the mouth, is helpful in recovering small objects.

Summary

Isolation of the operating field is essential for best results in the operating field. Operative dentistry cannot be executed properly without proper moisture control and good access and visibility.

Conclusion

Isolation should be part of the treatment carried with every patient in every clinic, not only for providing standard care to patient but also for the dentist benefit ,as to avoid communicable diseases

Bibliography

Fundamentals of Fixed Prosthodontics, third edn,

Herbert T. Shillinburg Contemporary Fixed Prosthodontics, Rosenstiel Clinical Periodontology, 10th edn, Carranza. Art and Science of operative dentistry- Sturdevant 4th

edition Krishna D, Chettan H. gingival displacement in

prosthodontics:A critical review. J interdispilinary dentistry 2011;1(2):80-6.

Abdulaziz Malbaker. Gingival Retraction - Techniques and Materials: A Review. Pakistan Oral & Dental Journal December 2010;30,2: 545-51

Bowels WH, Tardy SJ. Evaluation of new gingival

retraction agent. J Dent Res 1991;70:1447-49 Weir DJ, Williams BH. Clinical effectiveness of

mechanochemical tissue displacement methods. J Prosthet Dent 1984; 51:326-29

Shaw DH, Cohen DM. Retraction cords with aluminum chloride: Effect on Gingiva. Oper Dent 1980;5:138-41.

The length of cord should be sufficient to extend

approximately 1mm beyond the gingival width of tooth preparation.

Cord placement should not abuse the gingival tissue or damage the epithelial attachment.