There is an abundance of evidence that indicates sealants are effective in the prevention and progression of non-cavitated carious lesions. The authors of a study published in 2018 pondered the possibility that sealing cavitated lesions without carious tissue removal could be an option in minimizing invasive treatment. The aim of the study was to demonstrate how sealant material may “arrest the caries disease process, promoting lesion remineralization and/or arrest, while maintaining dental pulp vitality and retaining tooth structure, which can be achieved by avoiding unnecessary invasive treatment.”1
The methods suggested in this study are not limited to sealant material. The main objective is to successfully achieve a hermetic seal that isolates the carious lesion from the oral environment. The authors suggest this can be achieved using resin or glass-ionomer sealant material, resin-based restorative material or in the case of primary teeth, stainless-steel crowns. The individual situation should be assessed to determine which method is most appropriate.
The authors explain the reason behind removing carious is to provide hard tooth structure to achieve a good seal. Previously, it was thought that carious tissue was “infectious” and needed to be removed to halt further infection. We now know this is untrue, carious lesions are a result of the imbalance between demineralization and remineralization often initiated from dysbiosis of the oral microbiome. The authors state, “by sealing in lesions, without the need for any tissue removal, the bacteria proliferation can be stopped, and carious lesions arrested.” This is supported by multiple studies that confirm lower numbers of viable bacteria found under sealants that were placed over a carious lesion. The reduction has been determined to be at least 100-fold.
Although sealing over carious lesions has been shown to be successful at arresting the caries process since the 1970’s, it is still quite an underutilized method of managing oral disease. The obstacle most clinicians have with using this method is that they are unsure of what happens if you seal over a carious lesion. Though there is an abundance of evidence that has been replicated ad nauseum, showing that properly placed sealants arrest the caries process, clinicians are still hesitant to use them. Interestingly, recently there have been 3 large clinical trials that assessed the ability of sealants to arrest decay in occlusal caries lesions with follow up periods between 22-44 months. All three studies showed that sealing over lesions was a successful method for arresting carious lesions.
Another study cited in this article was a 10-year study that compared the progression of carious lesions on sealed surfaces and unsealed surfaces the results showed a median annual percentage of progression at 2.6% for sealed versus 12.6% for unsealed carious teeth. The caveat to all this information is the need for sealants to be closely monitored and touched up periodically to maintain integrity.
The extent of the carious lesion is a determining factor when deciding if a sealant should be applied. In a systematic review evaluating the depth of the lesion being sealed determined, “shallow or moderately deep lesions are likely to be successfully managed by sealants, but that there is not enough evidence to make recommendations for deeper lesions.” This indicates that deeper lesions are not candidates for this method to manage the carious lesion currently.
The authors conclude by making a couple of clinical recommendations:
- “Where there is significant breach in the surface integrity of the tooth, but the lesion still extends into dentin, sealing the tooth/lesion without tissue being removed is an effective treatment option that should be considered.”
- “Where there is significant breach in the surface integrity of the tooth but there is still enough sound tooth tissue to provide bonding for an adhesive restoration, sealing in the existing carious tissue might be possible.”
Do you utilize sealants in your current daily practice? Does the idea of sealing over a carious lesion concern you? If so, what further evidence would you like to see to change your mind? If you place sealants, are you checking them regularly to determine if they need to be touched up?
- Fontana M, Innes N. Sealing Carious Tissue Using Resin and Glass-Ionomer Cements. Monogr Oral Sci. 2018;27:103-112. doi:10.1159/000487837
