MR. CAPUTOUNIT #2 LESSON #5

Endodontic Instruments

Today’s Class

Driving Question: What are the instruments used during an endodontic treatment?

Learning Intentions: We will be able to describe endodontic instruments, accessory instruments, and medicaments necessary for endodontic treatment.

Anchor: Why is the shaping an cleaning of a root canal extremely important?

Pulpotomy

Removal of entire coronal pulp in pulp chamber, leaving only vital pulp within roots

Root canal’s pulp is retained and treated with medication to preserve its vitality and function

Usually done on primary teethContraindicated: fistula or an abscess, tooth

crown is nonrestorable, profuse hemorrhage, extreme tenderness to percussion, mobility, necrotic pulp, or pulp stones

Pulpotomy Procedure

Pulpectomy

Most common endodontic procedureInvolves removal of the entire pulp from

pulp chamber and from root canals of a nonvital tooth

Indications: cooperative patient teeth with poor chance of vital pulp treatment for space maintenance absence of surrounding bone loss from infection expectation of ability to restore tooth in the

future

Procedure for Pulpectomy

Initial x-ray is takenAnesthetic is administeredDental dam is placedDentist cuts through enamel and dentin with

a high-speed handpiece burSlow-speed handpiece round bur and possibly

spoon excavator is used to remove all decayed tooth structure

Procedure for Pulpectomy

Tooth opening is deepened and widened to allow access into pulp chamber(s)

Location of each root canal is determinedInfected pulpal tissue is removed

(extirpation)File(s) are placed into canal of tooth prior

to second x-raySecond radiograph is exposedFiles are measured

Root Canal Procedure

Shaping and Cleaning

Each root canal is prepared and shapedDebridement on root canal is acheivedSmaller file or reamer is used first, then

next larger size, to increase canal’s widthTapered files are used either by hand or

rotary instrument in a slow-speed handpiece

Filing is within 2 to 3 mm inside of tooth apex

Irrigation is done with bactericidal liquidsAbsorbent paper points are used

Obturation

Necessary to ensure a good seal at apex of root and for root canals to have no voids

Common material used to obturate is gutta percha, a thermoplastic rubber-like material

Gutta percha points are tapered so they ideally fit the canal after it is shaped

Endodontic sealing cements are used to hold gutta percha filling material in place

Thermafil or injection techniques can be used

Obturating a Root Canal

Image courtesy Instructional Materials for the Dental Team, Lex. KY

Final Restoration

Temporary restorative materials may be used to fill tooth and seal it from moisture contamination after root canal therapy

Dentist can either continue to prepare tooth for a permanent restoration or refer patient to another dentist for permanent restoration procedure

Endodontist will refer patient back to general dentist for post and core procedure and crown preparation

Permanent filling must be done in order to protect the tooth against fracture and recurrent decay

Post and Core Buildup

Endodontically treated teeth are usually already broken down and will become brittle with time because they no longer have a moisture supply

Post and core may be neededAll endodontically treated teeth will require a

crown as a final restoration to prevent future problems

Post

Placed within one or two root canalsServes to supply extra support for a core

when sufficient tooth structure does not existTwo main categories of posts:

custom fabricated prefabricated

Core Buildup

Required when there is extensive loss of natural tooth structure

Placement of pins for additional retention will also be evaluated

Most common core buildup materials are gold, amalgam, and composite

Goal of the core buildup is to establish the greatest stability and longevity of the restoration

Post and Core Buildup

Instruments and Accessories

Prepared in sterile packs or kitsSmall hand-operated endodontic

instruments and supplies are generally placed on disposable sponge or in compartmentalized box that can be sterilized and maintained in an orderly fashion

Several accessory items, such as instruments, filling materials, medications, irrigating solutions, and cements, must be readily available for use during endodontic procedures

Dental Dam

Essential during all endodontic proceduresIsolates the tooth and maintains sterile fieldPrevents contamination of saliva to root

canalsPrevents small endodontic instruments from

going down patient’s throatKeeps infected tissues, debris,

medicaments, and irrigating solutions from entering patient’s mouth

Improves visibility

Rubber Dam

Image courtesy Instructional Materials for the Dental Team, Lex. KY

Endodontic Explorer

Has two long, narrow, pointed working ends

Angled from shank in order to provide access to pulp canal inside tooth

Used to locate canal openings and explore pulp chambers and canals

Courtesy Hu-Friedy

Endodontic Spoon Excavator

Long, double-endedSimilar in shape to a

regular spoon excavator but has longer shank

Allows for detection of caries, coronal pulp tissue, or removal of cotton pellets that may be deep inside the crown of tooth

Courtesy Hu-Friedy

Broaches

Used to remove infected pulp tissue from within tooth’s pulp canal

Thin, flexible, tapered, and pointed, with a series of sharply pointed barbed projections that curve backward

Fragile and used with careDisposed of in biohazard sharps container

Reamers

Used to enlarge pulp canal after broaches Used with reaming action or filing actionTapered and pointed with spiral cutting

edgesCutting edges of reamers are farther apart

than those found on endodontic filesAvailable in many sizes, beginning with size

10 and continuing in intervals of 5 up to size 60 or intervals of 10 through size 140

A step-up process

Endodontic Hand Reamer

Courtesy DENTSPLY/Maillefer

Files

Look like reamersK-type, H-type (Hedstrom), and S-typeStandard numerical size designationStandard color codingSizes begin with size 8 and continue through

size 140Files lengths are 21 mm, 25 mm, and 27 mm

Files

Available in carbon steel, stainless steel, or nickel-titanium alloy

Newer titanium files have strength and flexibility

Sterilized through dry heat, autoclave, bead sterilizer

Disposed of in biohazard sharps container

K-type Files

Made of carbon steelTapered and pointed with tight spiral cutting

edges arranged so that cutting occurs with rotating stroke

When dentist pulls instrument out of tooth, cutting edges scrape against walls, removing necrotic tissue

Hedstrom Files

Shaped like series of cones that become larger from tip toward the handle

Sharp blades of these files cut aggressivelyUsed in push-pull motion and not rotated as

the K-type files

S-type Files

Made of stainless steel as opposed to carbon steel

Stainless steel bends more easily, is not as brittle, is less likely to break compared with carbon steel, and can be autoclaved without becoming dull

Have S-fluted design

Barbed Broach, K-Type File, and a Hedstrom

Endodontic Stops

Small round pieces of rubber, plastic, or silicone

Placed on reamers, files, or even broaches

Mark measurement of root canal

Prevent injury or perforation of apex

Courtesy DENTSPLY/Maillefer

Endodontic Measuring Gauges

Determine working length

Many designs for endodontic rulers

All endodontic rulers measure files, reamers, and broaches in millimeter increments in various designs