The most common scenario is the case of decay that has gotten so deep into the tooth that on the x-ray it looks like it's already reached the nerve of the tooth. The dentist tells you it looks like you need a root canal....Sometimes the dentist will see "a shadow" at the tip of the root. That indicates bone loss that results from the changes in chemistry that happens when a tooth has already abscessed (is infected) and the nerve has already been dead for a while (probably several months or longer). In that case there is no choice other than extraction or root canal treatment (RCT).But often there is no clearly defined shadow at the end of the root so determining whether it needs a RCT or not is a bit of a puzzle and the dentist has to be a kind of detective putting many clues together. Many times the clues point to RCT for sure, but sometimes it's still a puzzle. In those cases the dentist has to drill out the old fillings and decay and see how deep the decay goes. If he drills carefully he can sometimes get a all the decay out and still see that the nerve has not been reached. That's good - just a filling should fix it. Sometimes after getting all the decay out there will be a small spot where the nerve has been reached and that spot will normally bleed a little. That's called "an exposure". The text-book thing to do is RCT, but if the exposure is small, and if the bleeding is slight and the color of the exposure looks like pretty healthy tissue, the dentist can opt to do a pulp cap. A pulp cap just means trying to sterilize the area as well as possible, stopping the small bleeding, and placing an appropriate filling over it. In the past the technique was to place calcium hydroxide over it and then a normal filling (usually amalgam). Modern pulp-capping is mostly done using a bonded composite technique right over the exposure - with NO calcium hydroxide layer. When they are done well and in the right situation , pulp caps have a very good chance of working for a long time. It's just for those teeth in the in-between stage where the nerve is irritated but still alive and healthy enough to repair itself given a reasonable chance. The pulp-capping gives it a chance by getting rid of the decay and the bacteria that are in the decay, and by creating a clean dressing over it with the filling. It's not unlike cleaning out a dirty cut or scrape on your skin and placing a clean bandage over it.

 

 

An Indirect Pulp Cap is a procedure that is used when the dentist gets close to the nerve when removing decay. Regarded as a conservative treatment, the application of medicated cement in the temporary filling helps the pulp of the tooth to repair itself by containing the decay and allowing the buildup of a wall of tooth structure between the pulp and the decayed material. This is a "holding action". When your dentist removes the temporary filling, he may take an x-ray to determine if the pulp has healed. If so, the balance of the decay is removed, and a permanent restoration, or filling, can be placed in the tooth. In summary, your dentist is trying to keep your tooth alive, avoiding the need for a root-canal filling, pulp capping, or extraction of the tooth.

 

The Procedure of Pulp Capping

Step1: Examination and Vitality Testing

The dentist will look at the tooth and x-rays to determine if your tooth is a candidate.

In general, pulp capping is done if the tooth is still alive, meaning that the nerve has not died. To test this, the dentist may use one of many tests. One is an electric vitality test, where the dentist must gauge your reaction to different stimuli to the tooth.

Other ways to test a tooth are to ask questions and look at the tooth. The tooth should have its natural color and not be darkened. Surrounding gum tissue should be pink and not red and swollen. There should be no puss pockets in the gum near the bone of the tooth (which may indicate infection or abscess.) The dentist may even look at an x-ray to look for infection in the bone surrounding the tooth.

 

Direct pulp capping works at its best if the nerve has been exposed very recently due to a trauma to the tooth. In this case, the nerve has only been irritated for a brief period of time. Direct pulp capping also works well if there is only a minimal exposure of the pulp, such as 1 to 2 millimeters. The nerve may not have suffered as much damage then, and the cap doesn't have as much surface to cover.

Step 2: Removal of decay

 

In Direct pulp capping the dentist drills out the decay of a tooth, and then places a medicinal dressing over the exposed pulp. The tooth can then form dentin over the pulp.

 

Step 3: Filling

 

The dentist may do a permanent filling. Otherwise, the dentist will use a temporary filling. If so, you will come back about 6 months later to make sure dentin has formed over the pulp and then get the permanent filling done.