Root canal perforation is an artificial communication made between the root canal system and the supporting tissues of the teeth or with the oral cavity. Accidental root perforations, which can have serious implications, occur in about 2-12% of endodontically treated teeth.
During an endodontic treatment, which consists of root and crown pulp removal as well as antisepsis of the canals and sealing them with a special material, needles that are used for canal permeation can create these perforations.
The causes of perforations, are generally given by an error of the dentist in carrying out endodontic treatment, and include:
Uncooled or exaggerated use of rotary instruments during endodontic access preparation and root canal orifice search.
Attempting obturation in calcified canals or canals with sharp curvatures.
Incorrect preparation of the canal by using needles with a larger diameter than that of the canal
Inadequate preparation of access to canals
The location of the perforation may be different. If the perforation is close to the alveolar bone, inflammation may result, leading to epithelial resorption and communication with the oral environment. When this happens, the prognosis is poor.
If the perforation occurs in an area of the coronary structure that is surrounded by healthy bone, it is small and can be sealed immediately, leading to a better prognosis. Alveolar bone is available to support inflammation and create an environment for healing.
Signs and symptoms of a perforation include:
Sudden bleeding and pain during root canal instrumentation or root filling application are warning signs of a potential root perforation.
Oozing may occur resulting in sensitive teeth, abscesses, including bone resorption processes.
Downward growth of the gingival epithelium to the site of perforation.
The clinical treatment protocol for the repair of a dental perforation is performed either internally or externally. Internal repair is treatment performed in the root canal and can be divided into perforations that can be viewed directly (coronal third) or indirectly (middle and apical third).
If the perforation cannot be visualized directly, root canal treatment must be completed and then obturated with gutta-percha and a bio ceramic sealant. Because of the perforation, anesthetic solution or sterile saline should be used as an irritant instead of sodium hypochlorite.
In cases of a perforation that can be visualized directly (in the coronal third), a matrix should be used to fill the perforation before placing a permanent restoration. Unintentional extrusion of a restorative material into the alveolar bone may further compromise the prognosis of the perforated tooth. Biocompatible materials such as MTA are recommended for root fillings.
The sooner the perforation is identified, the better the prognosis is and can be corrected by the endodontist. If after root canal treatment, you are still experiencing pain in that tooth, it is best to return to your dentist for further investigation and to discover the cause of this present discomfort. Don’t ignore any signs that your tooth is still showing sensitivity.
