Indirect Pulp Capping
If complete removal of decay might lead to exposure of the pulp (and therefore more involved root canal treatment), a dentist may choose to stop decay excavation and place calcium hydroxide directly over the thin layer of dentin overlying the pulp.
A temporary restoration is then put in place. After a healing time of six to eight weeks for secondary dentin to form, the temporary restoration is removed along with any remaining decay.
This procedure can eliminate the need for more extensive root canal treatment.
Direct Pulp Capping
If the pulp of a permanent tooth becomes exposed due to trauma or during cavity preparation with a bur and is in a caries-free area, a small layer of calcium hydroxide is placed on top of the exposed pulp prior to restoration. It is then that Direct pulp capping is needed.
The patient is kept under observation for any symptom or adverse prognosis, in that case the endodontic root canal is performed.
However, if tooth remain symptom less, it is permanently restored.
The success of direct pulp capping varies a great deal depending on the size of the pulp-exposure hole, length of time exposed, and individual patient response.