principles of endodontics

8/11/2019 Principles of Endodontics

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INTRODUCTION



STERILIZATION OF INSTRUMENTS

DEBRIDEMENT

DRAINAGE

CHEMOPROPHYLAXIS

IMMOBILIZATION

AVOIDANCE OF TRAUMA

TREPHINATION



APPLICATION OF RUBBER DAM



Spectacles and protective bib Operator and seated nurse

Rubber Dam Placement



To maintain a safe and Aseptic operating technique

application of the rubber dam is imperative.

The rubber dam can be applied in less than 2 min and often

within 1 min.

1) Ivory No.9, for upper central incisors and all cuspids;

2) HF No. 211, for upper lateral and all lower incisors

3) HF No. 27, for all premolars;

4) HF No. 26, for all molars



Irrigation and suction procedures

Gutta Percha point transfer Setting working length of instruments



Instruments transfer

Parallel Transfer



Rubber dam forceps

Rubber dam frames



Ivory clamps, clockwise from top left.

14 Small and medium sized molars,14a Large molars,

1 Premolars

W8a Broken down molars



Clamp placed onto toothClamp in position

Dam fitted over tooth



Dam and clamp being fitted over

tooth togetherDam retained with rubber wedges

Safety chain (parachute)



Radiographic Views



STERIL I ZATION OF

INSTRUMENT



Sponges in a drawer



Ultra sonic bath



Burs for opening into the pulp chamber should be

autoclaved, dry heat sterilized, or sterilized by being dipped in

alcohol and flamed 2 or 3 times,

Instruments should first be cleansed of debris regardless of the

method used to sterilize them. They should be wipped clean by

squeezing the instrument blade with a 2 x 2 Gauze or cotton roll,

moistened with hydrogen peroxide or alcohol, while withdrawing

the instrument, using a counter-clockwise rotary motion before

subjecting them to sterilization



Cold sterilization of instruments, that is sterilization by cold

chemical solutions, is not recommended for two reasons

1. The process is not effective against all varieties of microbiallife.

2. The length of time necessary to destroy microorganisms

against which these solutions are effective namely, a minimum

of 20 min, is too large.

Absorbent points, broaches, files, and other root canal instruments

should be sterilized immediately before use in a hot-salt

sterilizer.

It consists essentially of a metal cup in which table salt is kept at a

temperature of between 4250 F [2180 C] and 4750 F [2460 C],



Hot air sterilizersalt sterilizer



Steam Sterilizer

Sterilization bag



The hot salt sterilizer has superseded the molten-metal sterilizer

and the glass – bead sterilizer because the metal or the small

glass beads occasionally clung to a wet instrument, escaped

detection, and then clogged the root canal as the instrument was

inserted

Glass beads may be effectively substituted for the salt in a hot-salt sterilizer, provided the beads are less than 1 mm in diameter.

Larger beads are not so effective in transferring heat to

endodontic instrument

The hottest part of the salt bath in the sterilizer is along its outer

rim. Starting at the bottom layer of salt; the temperature is lowest

in the center of the surface layer of salt.



DEBRIDEMENT



DEBRIDEMENT:

It is a principle of surgery that an infected wound must first be

cleansed mechanically. It is equally true that an infected root

canal must first be cleansed of debris. Devitalized tissue

encourages bacterial growth, whereas healthy tissue resists such

growth. Just as the surgeon rids the wound of debris initially, so

too must the dentist remove all necrotic material in the root canal

as soon as possible. In surgery, “ cleanliness is next to godliness



The pulp chamber and root canal should preferably be carefully

irrigated with sodium hypochlorite solution before one attempts

instrumentation because this solution has a solvent effect on pulp

tissue and also exerts an antibacterial effect. When the root canal

contains pulp remnants. They may be removed by

instrumentation at the first visit, provided care is taken to confine

all instrumentation to the canal. In all cases, a combination of

biomechanical and chemical means, namely, instrumentation and

irrigation, is necessary for complete debridement and cleansing of

the root canal.



DRAINAGE



When gross infection and swelling are present, the

surgeon generally makes an incision. To provide drainage. When

an acute alveolar abscess with much edema is present, drainage

should established at once, either through the root canal, or by

incision, or by both. The extent and condition of the swelling

govern the choice in each case. Drainage through the root canal

is preferable because it allows the pent-up pus and gas to escape.



Acute apical abscess producing

a facial swelling

Tooth drainage of an

apical abscess



CHEMOPROPHYLAXIS



If the patient has a history of rheumatic fever or

heart ailment involving the heart valves, an antibiotic such as 2 g

phenoxymethyl penicillin should be given 1 hour before the

operation and then 1 g 6 hours postoperatively. Erythromycin

[Erythrocin] may be substituted if the patient is allergic to

penicillin. The dosage is 1 g 1 hour before treatment and 500mg

6 hours after treatment.



IMMOBILIZATION



Immobilization is employed by the surgeon to

rest an organ, to allay pain or promote healing. Immobilization

reduces the potential for spreading of microorganisms. The

endodontist may well follow the example of the surgeon and

immobilize the affected tooth by relieving occlusal stress or by

relieving contact with apposing teeth if pain is present.



Polyvinyl splint

Polyvinyl splint in place



Composite splint



AVOIDANCE OF TRAUMA



Soft tissues should be handled gently,

delicately, as by a surgeon when operating. All trauma should be

avoided. Instruments should not be passed beyond the apical

foramen. Ripened Judgment may help to prevent this

complication, but instrument stops are more certain for beginners

and seasoned veterans alike.



TREPHINATION



Trephination as a means of relieving pain has

been used from time to time, By trephination is meant the

creation of surgical passage in the region of the root apex,

usually by a bur or special drill. The purpose of trephination is to

provide a channel for the escape of pus and blood, to relieve the

pressure of accumulated or gas in the jaw bone.



Apical Seal



Trephination has been advocated in the following cases:

Acute abscess where drainage through the root canal is

inadequate and much pain or swelling is present

Teeth with large areas of rarefaction

when the root canal has been overfilled and pain or

discomfort is present

And for postoperative pain following obturation of the canal by

conventional means



The dictum of Hippocrates

“WHATEVER YOU DO,

DO NO HARM,”

principles of endodontics

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