Quality Resource Guide

A Guide to Contemporary Endodontic Technology 5th Edition

www.metdental.com

that fits within 4-5 mm of the empty canal, then

placing a master cone point to the working length.

The System B plugger is driven through the

cone to reach its pre-determined position, then

maintained cold under pressure to condense the

gutta percha in the apical third of the canal. The

plugger is then heated again briefly to disengage

it from the mass and withdrawn promptly.

Another heat source device that could provide

the same functionality is the Touch ‘n Heat

(SybronEndo). This device comes with pluggers,

as well as spreaders that can be used for warm

lateral condensation. When using the System B or

the Touch ‘n Heat, the dentist can continue to back

fill the canal with a device that injects plasticized

gutta percha such as the Elements or Obtura III

systems (Kerr-Endodontics) or the Calamus unit

(Dentsply-Sirona). The Obtura System involves

a high temperature (again about 200 degree C)

thermoplasticized gutta percha (GP) that is injected

from a gun into the root canal. All systems require

sealer to be used; however, thermoplasticized GP

may fit better into the canals space irregularities.

Other systems are available in which there is a

core material with coating of gutta percha. An

example of this is GuttaCore (Dentsply-Sirona).

This system consists of GP on a harder core of

cross-linked gutta percha, which is fabricated in

different sizes. The instrumented canal is first

measured using a metal sizing instruments to

assess the size of the carrier to use. Next, the

suitable carrier is placed in a small oven that is

provided with the system, which warms the outer

GP to a temperature that can be molded into the

canal space. While these systems offer efficiency

and ease of use, they do not provide adequate

length control. Furthermore, retreatment of cases

with the older plastic carriers present special

challenges, as the core material is frequently

difficult to remove. GuttaCore was introduced to

facilitate the retreatment process.

It is important to emphasize that the seal in any

gutta percha filling is dependent on the adequate

application of sealer. Many different types of

sealers are available. They vary according to

the material and the setting time. While the seal

of most available sealers is comparable, it is

recommended that the dentist not use sealers

that contain paraformaldehyde as they have been

shown to be quite irritating to periapical tissues.

Eugenol-based materials also produce some

inflammation on the cellular level; however, they

are used by many dentists, as it is believed that

without microbial irritants, the inflammation is

subclinical in its magnitude. Calcium hydroxide-

based sealers are well tolerated. However, there

is no value for calcium hydroxide within a sealer,

since after setting the material cannot ionize and

raise the pH, which is how calcium hydroxide is

effective against microbial irritants. More recently,

several tricalcium silicate-based sealers have

been introduced. These sealers, like MTA, are

very biocompatible, and can be used in a single

cone technique with gutta percha. In addition,

they expand slightly upon setting, presumably

enhancing the seal. One clinical observational

outcome study showed reasonable success in

cases that had minimal canal preparation and

were obturated with a single cone and Bioceramic

(BC) Sealer (Brasseler).

Vital Pulp Therapy

In the last decade there has been a renewed

interest in direct pulp capping, partial and

complete pulpotomy of permanent mature teeth

with carious pulp exposure. The reason for this

renewed interest has been the demonstration is

case series, observational studies, randomized

trials as well as systematic reviews, that tricalcium

silicates enhance treatment outcomes in these

cases compared to calcium hydroxide.

73-75

The

advent of tricalcium silicate-based materials such

as Pro root MTA (Dentsply-Sirona), neoMTA 2

(Avalon Biomed), Endosequence Root Repair

material (Bioceramic Putty) (Brasseler) and

Biodentine (Septodont), provides a wealth of

biocompatible, and antimicrobial materials that

have good sealing abilities. The original ProRoot

MTA does stain teeth in the long-term, and so

the other options listed are more appropriate,

especially in anterior teeth. The key to success in

these cases is adequate diagnosis of reversible

versus

irreversible

pulpitis.

Therefore,

the

following criteria are generally used to ascertain

that the case is suitable for vital pulp therapy: Pulp

responsive with brief sharp response to cold

•

No periapical pain or radiographic changes

•

Patient consents to treatment after options are

discussed

•

Upon access vital pulp is seen, and the

bleeding is easily controlled by a cotton pellet

and hypochlorite

•

Recall in 3-6 months, asymptomatic, responsive

to pulp testing and no apical changes.

Regenerative Endodontics

There has also been a growing interest in the

regeneration of pulp following necrosis in teeth

with immature apex. The reason for this interest

is a combined interest in promoting the continued

development of the root in immature teeth, as well

as the surge of information on stem cell research

that offer the possibility of regeneration of the pulp

dentin complex.

Immature teeth with pulp necrosis and apical

lesions present a special problem because of the

inability to perform traditional endodontic treatment,

the weak structure of the tooth and the lack of

alternative treatments for the young child. Seminal

case reports have introduced the technique of

pulp revascularization, following disinfection with

antibiotic mixtures and induction of a blood clot that

is covered with MTA

.77,78

Numerous case reports,

case series, cohort studies, randomized trials

and systematic reviews have shown that in these

cases control of infection and increase in root

length and dentin thickness are possible. Animal

studies have revealed that most of the mineralized

tissue following revascularization is cementum or

bone, and that the single most important factor

in revitalization is bacterial control.

79.

As noted,

MTA placed in the chamber and some antibiotics,

such as minocycline, can cause significant

discoloration. Therefore, newer tricalcium silicates,

non-minocycline antibiotics (such as metronidazole

and ciprofloxacin together with a cephalosporin) or

regular calcium hydroxide medicament can be used

to control the infection. Several randomized trials

are being conducted to further optimize the protocol