Internal resorption is a rare dental condition where the inner structure of a tooth, specifically the dentin and pulp tissue, begins to break down from the inside out. This pathological process involves cells called odontoclasts, which normally create dentin, but in this condition, they instead erode the tooth’s internal hard tissues, resulting in the loss of tooth structure.
Causes and Symptoms of Internal Resorption
Internal resorption commonly originates from chronic inflammation within the tooth’s pulp, the soft tissue containing nerves and blood vessels. This inflammation can be triggered by various factors, including physical trauma to the tooth, even if the injury occurred many years prior. Untreated cavities that lead to infection of the pulp, known as pulpitis, can also initiate this inflammatory process. Additionally, complications arising from certain dental procedures, such as excessive heat generated during restorative work or tooth transplantation, are sometimes associated with the onset of internal resorption.
Internal resorption often remains without symptoms in its early stages, frequently being discovered during routine dental examinations. However, a distinctive visual sign, sometimes called the “pink tooth of Mummery,” may appear if the resorption progresses. This occurs when the internal breakdown thins the tooth’s outer layers, allowing the highly vascularized granulation tissue within the pulp to become visible through the enamel and dentin, giving the tooth a reddish or pinkish hue. While pain is not a common early indicator, it can develop if the resorption advances significantly, potentially leading to an infection or a perforation of the tooth structure.
The Dental Diagnosis Process
Internal resorption is most frequently identified through dental radiographs, commonly known as X-rays, during routine check-ups. On an X-ray image, the dentist looks for a distinct, typically round or oval-shaped dark spot, referred to as a radiolucency, located within the pulp chamber or the root canal of the affected tooth. The appearance of this internal lesion is usually symmetrical, with sharp, smooth, and clearly defined margins.
For a comprehensive understanding, a Cone Beam Computed Tomography (CBCT) scan can be used. This advanced 3D imaging technology provides detailed cross-sectional views that allow the dentist to determine the size, shape, and location of the resorptive defect. This detailed three-dimensional information is valuable for accurate treatment planning, especially in complex cases.
Available Treatment Options
The primary approach for treating internal resorption is non-surgical root canal therapy. This procedure aims to eliminate the inflamed pulp tissue causing the resorption. During treatment, a dentist or endodontist accesses the inner part of the tooth, meticulously cleaning and disinfecting the entire internal canal system to remove any remaining vital or necrotic tissues.
After cleaning and disinfection, the hollowed-out space inside the tooth is filled with a biocompatible material. Mineral Trioxide Aggregate (MTA) is often used to repair the resorbed area due to its favorable properties, including good sealing ability, biocompatibility, and its capacity to promote healing. MTA is beneficial in cases where the resorption has created a perforation in the tooth root, helping to seal and strengthen the weakened tooth structure.
If the internal resorption is too extensive, has significantly perforated the tooth root, or has weakened the tooth structure beyond repair, tooth extraction becomes the only viable alternative. Removal is necessary to prevent further complications or infection.
Prognosis After Treatment
When internal resorption is identified and treated early with root canal therapy, the prognosis for the affected tooth is very good, with high success rates. The treatment effectively stops the resorption process permanently by removing the active inflammatory tissue. This early intervention helps preserve the tooth’s structural integrity and prevents further damage.
In contrast, if internal resorption is left untreated, the destructive process will continue unabated. This ongoing breakdown will progressively weaken the tooth, making it susceptible to fracture, developing an infection, and ultimately leading to irreversible tooth loss. Following a root canal procedure, the recovery period is straightforward, with patients experiencing minimal discomfort. Should tooth extraction be necessary due to extensive damage, discussions regarding tooth replacement options, such as dental implants or bridges, would follow with the dentist to restore function and aesthetics.