Retrograde filling is a microsurgical oral procedure to remove the root tip (apex) of an infected tooth containing a dental granuloma, a cyst or an abscess. In most cases the endodontist will use a dental operating microscope the perfectly see the area he or she is operating on. After removing bacteria and the infected gingival tissue, the clinician will seal the root canal with biocompatible material to prevent new bacteria coming in and, therefore, a new infection.
The main feature of retrograde filling is that the endodontist will perform the surgical procedure passing through the gingiva and bone surrounding the tooth instead of through the dental crown as during a conventional root canal treatment. What does it mean?
Step by step retrograde filling procedure description
To prepare the oral surgery, your endodontist will fully examine your mouth and take X-rays that will be useful to get an idea of the infection depth.
Because the retrograde filling is a surgery, you may be given antibiotics before the surgery and you should continue to take them even after the orthodontic treatment following your dentist prescription.
In order to treat an abscessed tooth, remove a cyst or a dental granuloma performing a retrograde filling, the endodontist has to administer you the local aesthetic to numb the small area he will work on. The second step is to cut the gingival tissue to expose the jawbone that holds the tooth in place. With a sonic drill, your doctor will create a small hole to reach the tip of the tooth root.
Once the apex is visible, the last 2 or 3mm of the tooth that contains the infection will be cut. To complete the root-end filling, the remaining 3 or 4mm of the tooth root is cleaned and sealed by the oral surgeon using a surgical microscope and ultrasonic instruments.
There are different materials your doctor can use to seal the root of the tooth such as: amalgam, composite resin or mineral trioxide aggregate (MTA). All of them are biocompatible materials meaning that they do not cause allergic reactions or cancer.
Root canal treatment vs retrograde filling.
You may wonder why the dentist has to pass through the gingiva and bone to reach the infection if the conventional root canal treatment does the same and is not so invasive as the retrograde filling.
Let’s say that the main scope of both endodontic procedures is to save the tooth that will remain in place and continue to be used in chewing and speaking correctly.
In the root canal procedure, the dentist can easily create a small hole in the dental crown to get access the root canal. With different endodontic file sizes he or she can completely remove the infected tissue and reach the tip of the tooth only if the root is straight. In other cases it will be very difficult to perfectly clean the affected area by removing all bacteria. That’s why infection may come back or restart after the first or even the second endodontic treatment.
In addition, orthodontic files are very thin and it is easy that they break within the root canal and it is almost impossible to remove them. In this case it is easy to guess that the broken orthodontic file doesn’t allow the root canal retreatment and the root-end filling is the only option the dentist can go with.
Unlike in the root-end filling, In the root canal therapy there is no root-resection, the tooth remain the same size it was before the procedure.
In case of even the retrograde filling will fail, the last resort is to remove the infected tooth in order to avoid the infection to spread to neighbouring teeth or to other parts of the body (through the blood flow).
Recovery and healing time
Swelling and sore are expected after the procedure and the next day, so do not worry if you see your cheek to get puffy.
Pain and swelling can easily be taken under control with over-the-counter anti-inflammatory (Advil, Motrin etc.) and pain killers
To promote a more fast recovering, it is highly recommended to avoid to brush or rinse the operated area in the next 2 or 3 days. Smoking, crunchy food are also dangerous because they can easily break the suture.
if not self-absorbing, gingival stitches will be removed a week after the surgery while swelling and soreness completely disappear within 2 weeks or less.