Treatment of a tooth before endodontic therapy is paramount for success.1 The need to achieve isolation and provide a means of maintaining a seal for the intracanal medicament and the temporary restoration cannot be overemphasized.2,3 The use of malleable copper bands or preformed bands as a stabilizing matrix has been well-documented.1,4 These bands are quite useful for provisionally restoring severely broken-down teeth.
However, maintaining access to an exposed pulp during this process can be difficult. While attempting to restore the tooth, the dentist might find that the canal system to be treated becomes blocked easily. Therein lies the problem: how to provisionally restore the multiple surfaces of a badly broken-down tooth to allow for clamp and rubber dam placement while maintaining the ability to access the canal system. This article describes a simple, quick, predictable way of provisionally restoring a badly broken-down, grossly carious, mandibular left canine that allows for proper rubber dam isolation, while maintaining access to the root canal system.
PROCEDURE
The patient’s left mandibular canine (tooth no. 22) exhibited clinically gross circumferential caries that approximated the pulp. He explained that the tooth had become symptomatic during the previous four weeks, with sensitivity to hot and cold liquids and lingering pain. On examination, I found that the tooth was tender to percussion. A pretreatment radiograph revealed caries extending nearly to the pulp and a widened periodontal ligament space. Pulp vitality testing confirmed a diagnosis of irreversible pulpitis.
After administering a local anesthetic, I removed the caries while preserving as much tooth structure as possible, including unsupported enamel. I created a hollow, modified form to use as an internal matrix or canal extender. In this case, the end of a Benda Brush applicator (Centrix, Shelton, Conn.) worked quite well. I tapered the plastic tube and cut it to a length that would allow it to extend past the confines of the original tooth structure. I then placed an endodontic file, which had been secured with a removable loop of dental floss to prevent aspiration,5 through the prepared tapered sleeve. I coated the sleeve with lubricant and placed the file with its tapered sleeve into the root canal.
An endodontic file of sufficient diameter and stiffness anchors the tapered sleeve that enables the practitioner to access the root canal (Figure 1
). The remaining shell of the tooth is etched, rinsed, dried, coated with a bonding agent of choice and light-cured. Next, I place a polyester film (Mylar, DuPont, Wilmington, Del.) matrix to act as an external band and proceed with the provisional restoration, using a material of choice. For this patient, I used a flowable compomer resin. After curing the resin, I removed the polyester film matrix assembly along with the tapered sleeve and endodontic file. Once shaping and finishing were completed, I easily isolated the tooth (Figure 2).
