As mentioned in my previous article on “Management of Deep Carious Lesions,” there are a multitude of approaches to removing caries while maintaining pulp vitality.
When caries are in close proximity to the pulp, an indirect pulp cap can be performed. In this procedure, much of the infected and affected dentin is removed without exposing the pulp in a vital, healthy tooth. This is followed by the placement of a medicament (such as calcium hydroxide or a bioactive material) in order to promote the formation of tertiary dentin1.
Caries excavation when in close proximity to the pulp is traditionally performed in one of two ways:
1) Stepwise caries removal: This procedure involves cavity preparation to remove all carious enamel, but leaves carious dentin in place adjacent to the pulp chamber. A medicament is placed over the remaining caries, a provisional restoration is placed and the patient is scheduled for a second appointment. At the second visit, the provisional restoration and remaining caries are removed, and a definitive restoration is placed. The goal of a stepwise approach is to both promote the formation of tertiary dentin and change the environment within the tooth to prevent further progression of the carious lesion 2.
2) Single-visit excavation: With a single-visit indirect pulp cap, as much of the carious lesion as possible is removed without inducing a pulpal exposure. A medicament is placed in the deepest aspect of the preparation, and a definitive restoration is placed. Unlike the stepwise approach, a single-visit excavation does not require a second visit to restore the tooth, and there is no risk of an inadvertent pulpal exposure when re-entry of the tooth occurs 3, 4.
What works best?
Both procedures can be used to successfully treat vital teeth with caries in close proximity to the pulp. Hoefler's systematic review comparing the two procedures found both techniques can be successful, and that teeth restored using a single-visit technique were more likely to remain vital at follow-up appointments (96 percent vs 83 percent at a three-year follow up)4. In our next article, we’ll discuss the direct pulp cap procedure.
References
1. Alex, G. “Direct and indirect pulp capping: A brief history, innovations, and clinical case report.” Compendium. March 2018: 39 (3): 182-189.
2. Bjorndal, L. et al. “A clinical and microbiological study of deep caries lesion during stepwise excavations using long term treatment intervals.” Caries Res 1997; 31: 411-417.
3. Bjorndal, L. “Indirect pulp therapy and stepwise excavation.” Pediatric Dentistry: May/Jun 2008: 30 (3): 225-229.
4. Hoefler, V., et al. “Long-term survival and vitality outcomes of permanent teeth following deep caries treatment with step-wise and partial-caries-removal: A systematic review.” Journal of Dentistry. 2016: 54: 25-32.