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Clinical Case: Smart Restoration following Endodontics Dr John Rhodes

Clinical Case: Smart Restoration following Endodontics, Dr John Rhodes


In this clinical case study, Dr John Rhodes, owner of The Endodontic Practice (Dorset,UK) explores the importance of coronal sealing, SDR® (Smart Dentin Replacement) and new restoration techniques which are paving the future for endodontic practices everywhere.

Adequate coronal seal following endodontic treatment is imperative. A good root filling and good restoration providing coronal seal achieve the best outcome.1

As a specialist endodontist, I am often required to provide core build-ups on teeth that have had endodontic treatment and in every case the access cavity must be sealed adequately to prevent coronal leakage. Historically, molar teeth have often been restored using the Nayyar core technique2 with amalgam. This avoided the need for metal posts, which had been shown to increase the risk of tooth fracture. The technique is predictable but with significant advances in bonding technology and composite materials since publication, there has been concurrent propensity amongst patients and dentists to avoid amalgam when possible. The long-term prognosis for posterior endodontically treated teeth however, is significantly improved by cusp coverage.3

In large cavities, composites have traditionally been used either combined with glass ionomers and compomers or in increments, each layer being light-cured to avoid the affects of polymerisation shrinkage and stress as the composite hardens.4 Layering techniques can result in voids through which potential microleakage could occur; the technique is also time-consuming. Polymerisation stress resulting from the polymerisation shrinkage of composite restorations can lead to numerous adverse clinical effects, including de-bonding, post-operative sensitivity and marginal discrepancies.4

SDR is a one-component, fluoride-containing, light cured, radiopaque resin composite restorative material. It has been designed for use as a base in class I and II restorations.5

SDR is a flowable, self-levelling composite that can be placed in 4mm increments with minimal polymerisation stress. The self-levelling feature allows intimate adaptation to the prepared cavity walls. Working with an operating microscope, it is reassuring to see the SDR material flow into the ramifications of the cavity. This is therefore a useful material for rapidly sealing the bulk of the access cavity in endodontics, following which, a single shade composite such as ceram.x one UNIVERSAL is used to create and refine occlusal detail. This simplified two-increment technique can produce a highly aesthetic composite restoration without encroaching heavily on surgery time. SDR works extremely well in the base of conventional access cavities where an unfavourable configuration “C” factor can make restoration with composite challenging.
In class II cases a matrix will be required. The Palodent® V3 sectional matrix system by DENTSPLY produces an anatomical profile and tight interproximal contact when working with composite. A matrix is selected and the nickel-titanium ring is used to open the interproximal space. Wedges can be placed through a “V” shaped notch in the ring to adapt the matrix to the base of the box. The wedges come in different sizes and can be “piggy backed” if more than one is required.

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Following molar endodontic treatment a core is being constructed. The Palodent V3 sectional matrix, ring and wedge are all in position. The matrix system is not affected by the rubber dam clamp. Good adaptation can be seen at the base of the distal box. The cavity has been etched and the bonding agent applied, this produces a “wet” appearance to the tooth substance. Using a rubber dam is preferable to allow good moisture control in the operative site. Following complete etching and application of suitable bonding agent, SDR can be dispensed into the cavity. It is important to check that the bonding agent has not pooled in the orifices in root filled teeth. The cannula tip can be inserted into the orifice of the root canal. Although a 4mm thickness can be confidently light-cured, it is perhaps advantageous to cure a thinner increment in the orifices and across the pulp floor as light penetration will be less predictable at the base of the access cavity. A further increment can then be added to a level approximately 2-3mm below cavity margin.

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Figure 2
SDR being dispensed into the cavity. In this case the composite is being applied with the aid of an operating microscope fitted with a yellow filter to prevent premature polymerisation. ceram.x one UNIVERSAL composite, which is radiopaque and available in seven shades (covering the full VITA®6 range) is used to build up the marginal ridges and then individual cusps, spot curing between additions. The composite contains nano-ceramic particle technology, offering natural aesthetics, excellent handling characteristics and durability and is suitable for anterior and posterior restorations.

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Figure 3
The completed core prior to removal of rubber dam. Building up the core with a two increment technique is far quicker and results in much less occlusal adjustment being required.

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Figure 4
In this case the root filling in LL4 has failed and the LL5 is necrotic. Both teeth require endodontic intervention and restoration.

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Figure 5
The situation following endodontic treatment. A fiber-post was required in the LL4 and was bonded with a dual-cure composite. The LL5 did not require a post, but both teeth would eventually be restored with full coverage restorations.

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Figure 6
The LL4 and LL5 following restoration with SDR and ceram.x one UNIVERSAL.

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Figure 7
The post-operative radiograph. The root canal in the LL4 was re-negotiated and patency achieved. An apical seal is provided by 4mm of gutta percha and a fiber-post bonded into the remaining canal. The apical region of the LL5 has an apical delta and multiple foramina. The composite has been placed into the coronal part of the root canal to improve retention.

For more information  click on the links below 
ceram.x one UNIVERSAL

1 Kirkevang LL, Ørstavik D, Hörsted-Bindslev P, Wenzel A. (2000) Periapical status and quality
of root fillings in a Danish population. International Endodontic Journal. 33:509-11.
2 Nayyar A, Walton RE, Lionald LA. (1980) An amalgam coronal-radicular dowel and core
technique for endodntically treated posterior teeth. Journal of Prosthetic Dentistry.
3 Nagasari R and Chitmongkolsuk S (2005) Long-term survival of endodontically treated
molars without crown coverage: A retrospective cohort study. Journal Prosthetic Dentistry.
4 Truffier-Boutry D, Demoustier-Champagne S, Devaux J, Biebuyck J-J, Mestdagh M, Larbanois
P, Leloup G (2006) A physico-chemical explanation of the post-polymerization shrinkage in
dental resins. Dental Materials. Vol. 22, No 5 405-12.
5 Yamazaki PC, Bedran-Russo AK, Pereira PN, Wsift EJ Jr. (2006) Microleakage Evaluation
of a New Low-Shrinkage composite Restorative Material, Operative Dentistry. Vol. 31, No.
6, pp 670-76.
6 VITA is a registered trade mark of Vita Zahnfabrik H. Rauter GmbH & Co
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