POST-ENDODONTIC RESTORATION, INDICATION AND TYPES
PROBLEMS OF ENDODONTICALLY TREATED TOOTH
INDICATIONS AND
TREATMENT OPTIONS FOR POST-ENDODONTHIC RESTORATION
TYPES OF POST-ENDODONTIC RESTORATION
Anterior teeth
1. Composite resin restoration: In anterior teeth
that are minimally to moderately traumatized a direct composite restoration
will be the restoration of choice. The composite may be placed directly over the
gutta percha, which should ideally be cut back to osseous level, some
clinicians prefer to use a glass-ionomer base or dual cure composite base where
it can be difficult to light-cure composite. Placing composite below the level
of the cemento-enamel junction not only provides a good coronal seal but can
reduce the fracture susceptibility of the tooth
Composite achieves a good seal owing to its ability to bond
to tooth structure; it has good physical properties and can be selected by
shade and polished to achieve a good aesthetic result. It is possible to
internally bleach discoloured teeth before composite placement to achieve
excellent aesthetic results.
2.Ceramic or composite resin veneers
Veneers normally cover the entire labial surface of the
tooth including the incisal edge and through to the proximal contacts. Ceramic
or composite resin veneers are seldom recommended for endodontically treated
anterior teeth as it is not easy to incorporate the access cavity within such
restorations and often the tooth tissue loss means a significant reduction in
available surface area to bond to.
Ceramic or composite resin veneers
3. Metal-ceramic crowns
Metal-ceramic crowns are commonly prescribed when an
anterior, endodontically treated tooth is to be crowned and represent the main
non-adhesive restoration of the anterior dentition. A reduction of the labial
surface of approximately 1.8–2 mm is necessary. This reduction may
compromise the strength of the remaining tooth tissue; so caution should be
exercised before prescribing such a restoration.
Metal-ceramic crowns
4. All-ceramic crowns
All-ceramic crowns offer the clinician a superior aesthetic
result with often a reduced tooth preparation when compared to a metal-ceramic
crown. Some all-ceramic crowns can allow for a labial preparation of
1-1.5 mm, for example IPS eMax crowns. Tooth preparation must be very
precise with good rounded internal line angles so as not to concentrate stress
under the crown, which can lead to micro-crack formation and fracture propagation.
These crowns can be adhesively cemented
All-ceramic crowns
Posterior teeth
1. Amalgam restoration:
Amalgam has been used
as a restorative material with good long-term success. In recent years it has
lost popularity among some clinicians and particularly with patients over
concerns regarding the toxic effect of metal ions released by the amalgam
overtime, but primarily owing to its cosmetic shortcomings. However, amalgam
functions very well as a restorative material as it has a high compressive
strength and contrary to some, it has a safe, successful clinical history.
Amalgam restoration of Postendodontic restored tooth
2. Composite resin restoration
Composite resin restorations are rarely acceptable as
definitive long-term restorations for posterior teeth. Invariably, posterior
teeth undergoing endodontic treatment have lost significant amounts of tooth
structure. Extensive loss approximally and the deep access cavity can make it
difficult to restore the tooth to good anatomical shape and function.
Composite resin restoration on a Posterior tooth
This is often complicated by the need to overlay cusps to
reduce the chance of short- to mid-term cusp/tooth fracture. It may be
acceptable to accept composite as a definitive restoration where the access
cavity is limited to just the occlusal surface. Most commonly, composite resin
is used to buildup a core filling before subsequent crowning of the tooth.
3. Gold Onlays and crowns
Gold restorations have stood the test of time and are
renowned for their durability. The gold onlay enables preservation of sound
tooth structure as the preparation is conservative, this may infer greater
strength for the endodontically treated tooth. Gold is still the material of
choice for posterior teeth but this tends to be where aesthetics are not a
major concern. Upper second molars are good candidates for these types of
restoration or restorations where interocclusal space is limited or patients
are bruxists. Gold onlay preparation should include cuspal coverage of all
cusps.
GOLD ONLAY AND CROWN
4. Composite resin and ceramic onlays/crowns
The onlay preparation differs little from that used for
vital teeth. The internal line angles should be rounded, the preparation walls
slightly flare, rather than a chamfer preparation there is normally a 90°
shoulder finish. A minimum preparation depth of 1.5 mm and the proximal
boxes should extend above the contact point. Cuspal coverage is again advocated
to reduce the risk of tooth fracture.
Composite resin and ceramic onlays/crowns
5. Metal-ceramic crowns
Metal-ceramic crowns are the most commonly placed full
coverage restoration in the posterior dentition. Metal-ceramic crowns may also
be used as bridge abutments. Unfortunately the conventional approach to
preparing metal-ceramic crowns requires an extensive heavy tooth reduction to
create sufficient room for the restoration.
Metal-ceramic crowns
6.POSTS and Cores
Indications for posts In the restoration of endodontically treated
teeth the placement of a post is generally suggested if the amount of residual
tooth structure is not sufficient to support a core made of a plastic material
(amalgam or composite). The idea that the placement of a post does not
reinforce a tooth is indeed very popular and remains debatable.
Post retained restoration on endodontically treated teeth
COMPONENTS OF POST AND CORES
POSTS
CORES
CONCLUSION
In summary, After the root canal treatment, the dentist has
the task to restore the tooth and to return its form, function, and esthetics.
The restoration must have adequate retention without promoting damage to the
remaining dental tissue. The amount of remaining structure, position of the
tooth in the arch, functional and esthetic demands should guide the
appropriate choice of the post-endodontic treatment.
REFERENCES
Saunders W P, Saunders E M. Coronal leakage as a cause of failure in root-canal
therapy: A review. Dent
Traumatol 1994; 10: 105–108.
Reeh E S, Messer H H, Douglas W H. Reduction in tooth stiffness as a result of endodontic and restorative procedures. J Endod
1989; 15: 512–516.
Andreasen J O, Farik B, Munksgaard E C. Long-term calcium hydroxide as a root canal
dressing may increase risk of
root fracture. Dent Traumatol
2002; 18: 134–137.
Grigoratos D, Knowles J, Ng Y L, Gulabivala K. Effect of exposing dentine to sodium
hypochlorite and calcium hydroxide
on its flexural strength and
elastic modulus. Int Endod J 2001; 34: 113–119.
Post a Comment