Radically treated teeth can fail to heal, for example if the dentist does not find, clean and fill all the root canals in the tooth. Upper jaw molars, here as a more than 50% chance that the tooth has four root canals instead of only three. The fourth canal is often called “medial-buccal 2”, tends to be very difficult to find and often requires special tools and magnification in order to be seen (most common in the first maxillary molars, studies have shown a mean of 76% to 96% of the presence of the MB2 canal in These teeth), this infected canal may cause persistent infection or ‘flare-ups’ in the tooth. Any tooth can contain more than one root canal contrary to what is expected, and these channels may not be seen when the root canal is performed. Sometimes the tunnels may have an unusual shape, making them impossible to clean and fill completely. Therefore, some infected material may remain in the root canal.
Sometimes the root canal filling does not extend to the top completely, or the root canal is not filled as densely as it should be. Sometimes the tooth root may perforate while the root canal is being treated, making it difficult to fill the tooth. The hole can be filled with a root repair material such as a natural cement-derived mineral trioxide aggregate (MTA). The specialist can often re-treat failed root canals, after treatment the tooth has healed, often re-treatment years after the first radical procedure.
However, the survival or function of the endodontic tooth is often the most important aspect of the outcome of endodontic treatment, rather than healing of the apical part of the root only.[23][24] Recent studies indicate that the materials commonly used to clean the root canal space incompletely sterilize the canal. A properly restored (filled) tooth after root canal treatment gives long-term success rates of about 97%. In a large-scale Delta Dental Study of nearly 1.6 million patients who underwent root canal treatment, 97% kept their teeth 8 years after the procedure, although most untoward events, such as re-treatment, apical surgery or extractions, occur within the first 3 years after endodontic treatment primary. [25] Endodontically treated teeth are more susceptible to extraction due primarily to unrepaired carious destruction and to a lesser extent due to endodontic-related causes such as failure of endodontic treatment, vertical root fracture, or perforation (procedural error).[9]
collective issues
