Tooth resorption refers specifically to the inflammation and loss of dentin (inner tissue) or cementum (outer material) to absorption. Tooth resorption is classified internally and externally, depending on where the loss of tooth occurs. External resorption is much more common than internal resorption, and often easier to see than internal resorption because it commonly occurs on the outer surface of a tooth.
Internal resorption affects the inside of a tooth. This is usually caused by some form of injury to the tooth, such as trauma, chemicals or heat, or bacterial invasion of the pulp. It’s much less common than external resorption and most often affects men. Although it is a relatively rare entity, a higher prevalence of the condition has been associated with teeth that had undergone specific treatment procedures such as auto-transplantation. Many people are unaware they have internal resorption because of the lack of symptoms. They may be detected on X-rays taken during a routine dental exam. The first sign of internal resorption is usually a pinkish tinge to the tooth, which shows that the internal tissue is affected.
If the tooth is restorable and has a reasonable prognosis, root canal treatment is the treatment of choice. If there is too much tooth resorption, the tooth may be extracted. Early detection and a correct differential diagnosis are essential for successful management of the outcome to prevent over weakening of remaining tooth structure and root perforations.
In this case, the pink discoloration on the tooth was notice during a dental checkup. The internal resorption was confirmed by the digital x-ray.
The root canal treatment was completed as it's the only treatment option to save the tooth. There are much more challenges for root canal treatment with internal resorption. To make it even more challenging, the tooth has 5 canals. The root canal treatment was completed in one visit with dental operating microscope.
About 47% of maxillary first molars have 3 canals and 53% of them have 4 canals. Occasionally there are first maxillary molars with 5 canals.
This molar had MB1, MB2, DB1, DB2 and P canals. The internal resorption was near disto-palatal corner of pulpal chamber. The resorption was quite extensive and carefully removed with ultrasonic scaler. Fortunately there was no perforation. The resorbing dentine was very porous and full of blood with clastic cells.
The root canal treatment was very successful and the recovery was uneventful. A porcelain fused metal or zirconia crown will be made in the near future to protect the tooth from breaking.