I am old enough that I learned amalgam as the go to operative material. In those days when we encountered deep decay we followed a process of applying calcium hydroxide to the deep areas of the prep and expected good results in the formation of a dentinal bridge and survival of the pulp. When we transitioned to composite products like Dycal(Calcium Hydroxide) and Copalite disappeared. For me it has felt like there has been a void in my ability to pulp cap in the instance of deep decay under a composite. Using glass ionomer or RMGI is probably the most accepted technique. The challenges I have run into are the set time of the materials and the limited bond strengths to dentin. Earlier this year Bisco dental released a new product designed for just this purpose. I have been using it ever since and finally feel like I have a pulp capping product I can use with confidence.
TheraCal is a light-cured, resin-modified calcium silicate filled base/liner and can be used under both direct and indirect restorations. It is intended to protect the pulp and be used in deep areas of decay for indirect and direct pulp capping. The handling properties are very similar to flowable. Dispensed in a syringe with a small tip it is easy to place in even the deepest areas of the prep. It’s viscosity allows it to stay where it is placed. I place a small increment and then spread it with the tip of a perio probe. The material is then light cured so it sets immediately and does not delay the placement of the restoration. When using Theracal under an indirect restoration where you are going to provisionalize remember it is a resin. After the initial cure cover with glycerin and cure it again to eliminate the air inhibited layer, or clean with a cotton pellet and alcohol. Otherwise your bisacryl provisional material will bond to the TheraCal.
TheraCal stimulates repair of the pulp due to the release of calcium ions and the alkaline pH, creating a dentinal bridge similar to the effect of calcium hydroxide. It can safely be placed even with a direct exposure and has much higher bond strengths to dentin than RMGI. My hope would be to catch the decay before I need to consider pulp capping, but unfortunately I ask for the TheraCal frequently, but I;m glad I have it to ask for.