1. The Field of the Invention
The present invention relates to compositions and methods for isolating dental tissue for treatment thereupon. In particular, the present invention relates to polymerizable isolation barrier compositions and methods of using the same for isolating tooth surfaces. The polymerizable barrier compositions of the present invention may include constituents that enable the compositions to adhere to wet, dry, soft or hard oral tissues; to minimize injury risks due to heat from polymerization and/or light radiant energy from subsequent treatment(s); and that enable the barriers to be easily removed.
2. The Relevant Technology
Several dental procedures exist that use treatment compositions in the mouth that could be harmful and damaging to soft tissue. Harmful treatment compositions must be kept away from soft tissue such as the gums during such treatment procedures. There are other dental procedures that require a substantially dry tooth that must be maintained in a dry condition during a lengthy dental procedure to avoid damage.
In general, contact between a treatment composition and the cheeks and tongue of a patient can be minimized through the use of cotton rolls, absorbent isolators, rubber dams, rubber dam caulking or other conventional isolation techniques. The gums, adjacent dentin and surrounding sulcular tissues however are harder to protect from the treatment composition(s) due to their close proximity to the surfaces being treated and because the treatment composition is sometimes a freely flowable aqueous solution.
Although it is possible to incorporate some treatment compositions within a gel in order to inhibit the unwanted flow of the treatment composition from the desired treatment area, they generally must have a low enough viscosity to flow into the tiny crevices and other irregularities of the surface of the tooth being treated. Hence, it is generally impractical to have a treatment composition that is so viscous that it is not at least partially flowable.
In addition to adjusting the flow characteristics, the concentration of the treatment composition can be modified to reduce the damage caused by inadvertent contact with surrounding sulcus and gum tissues. However, significantly reducing the concentration of a treatment composition also reduces its ability to treat the tooth, thereby increasing the time in which the treatment composition must remain in contact with the surface being treated. In general, treatment compositions strong enough to adequately treat teeth may also damage and irritate surrounding soft gum tissues.
Rubber dam technology was developed as a means of isolating a tooth for treatment and also for protecting the vulnerable soft tissue. FIG. 1 illustrates the installation of a rubber dam 10. It can be seen that rubber dam 10 has been placed over the teeth 14 and then rubber dam 10 is fitted with a dental instrument 16 by pushing rubber dam 10 up to the gum line 12. This procedure must be carried out on each tooth. Rubber dams, however, have several disadvantages. One disadvantage is that rubber dams can be difficult to install. Rubber dams have a hole-punched perimeter shape that may or may not isolate soft tissue next to the tooth because the tooth perimeter shape might have concavities. For example, where a tooth forms an unusual groove or concavity, a hole-punched rubber dam may leave an exposed space through which treatment compositions could leak that could harm soft tissue. If the seal created by a rubber dam is faulty, soft tissue is exposed and likely to be damaged by the treatment composition.
Another disadvantage to rubber dams is that they are prone to tearing once placed over the tooth. If the rubber dam begins to tear in the middle of a dental procedure, the procedure must be aborted and a new rubber dam installed. This is time consuming and the new rubber dam may likewise tear at or near the same point of the treatment that the original rubber dam began to tear. Additionally, when the rubber dam tears during a procedure, it may be too late to prevent the treatment compositions from contacting the soft tissue and therefore too late to prevent soft tissue damage.
Another disadvantage to rubber dams is that they often cause patient discomfort. FIG. 2 illustrates installation of a rubber dam 10 with rubber dam clamps 22 and a frame 20 that covers the labia 24 and the tongue 26. When, for example, a labial surface of a tooth is the only surface that needs to be isolated, rubber dam 10 may cover more than the teeth.
Additionally, where an intense dental curing or laser light is being used, heat buildup incidental to use of the light may cause patient discomfort due to heating of the rubber dam. Intense heating of the soft tissue will necessitate intermittent use of the dental light, a practice that slows the clinician in his procedure.
One attempt to overcome the problems associated with rubber dams provided a blue flowable resin that can be applied onto a dental substrate and then be polymerized. Due to the color of the resin, it absorbs light energy which resulting increases the risk of injury to soft tissue in contact with the resin. Additionally, the resin is hydrophobic which significantly hinders its ability to adhere well to dental tissues. Another significant problem with this resin is that it is too strong and consequently the polymerized resin is very difficult to remove. Difficulties related to excessive strength are only exacerbated by application of the resin onto dental surfaces such as wide open embrasures and undercuts. For example, open embrasures are typically filled from both sides which results in the embrasures being completely filled and solidly anchored. After polymerization, it is very difficult to remove the resin and may require prying instruments or even high speed drills. Similarly, undercuts present a problem when resin becomes lodged into the openings or crevices and it may then necessary be to remove the resin with dental tools which the require the use of some force such as prying instruments or excavating tools.
In light of the foregoing, it would be a significant advancement in the art to provide isolation barrier compositions and methods for protecting sulcular and gum tissues surrounding a tooth being treated from intense cumulative heat buildup in order to avoid patient discomfort and to expedite dental treatments that use a curing or laser light
It would also be a significant advancement in the art to provide isolation barrier compositions and methods for protecting sulcular and gum tissues surrounding a tooth being treated that can be easily removed following a dental procedure.
It would be a further advancement in the art to provide compositions and methods that result in a quickly and easily applied barrier to maintain a treatment composition within the area of the tooth that is desired to be treated.
Another advancement in the art would be to provide compositions for an isolation barrier material that, upon application to the dental substrate and polymerization, are sufficiently weakened to facilitate its removal in discrete, approximately tooth-sized segments or larger with a tweezers-like instrument from the dental substrate after use in a dental procedure.
Another advancement in the art would be to provide compositions for an isolation barrier material that, upon application to the dental substrate and polymerization, are resistant to deformation at the external surface of the barrier due to incidental touching but that remain adherent to the dental substrate at the internal surface of the barrier.
Another advancement in the art would be to provide a composition for an isolation barrier material that, upon application to the dental substrate and polymerization, is of a generally small size and conducive to a customized fit that avoids inducing patient discomfort.
Such polymerizable isolation barrier compositions and methods for using them are disclosed and claimed herein.