Decoronation is a specialized dental surgical technique used to manage severe trauma to permanent teeth, particularly in growing children and adolescents. This procedure involves removing the tooth’s visible portion, the crown, while preserving the entire root structure within the jawbone. Decoronation is an alternative to tooth extraction, which typically causes significant loss of surrounding bone. By keeping the root fragment submerged below the gum line, the technique maintains the physical space and biological structure of the tooth socket.
The Purpose of Decoronation
The most common reason for performing this procedure is ankylosis, the fusion of the tooth root directly to the jawbone following a traumatic injury. Ankylosis occurs when the periodontal ligament, which normally cushions the tooth, is damaged and replaced by bone. In a growing patient, this fusion is problematic because the ankylosed tooth cannot move or erupt like adjacent healthy teeth.
As the child’s jaw and surrounding alveolar bone grow vertically, the fused tooth remains fixed, creating the appearance of a “sunken” tooth, known as infra-occlusion. This lack of vertical bone development can lead to a noticeable deformity in the bone ridge, complicating future dental restoration. The objective of decoronation is to halt infra-occlusion and preserve the dimensions of the alveolar bone.
The submerged root acts as a biological scaffold, stimulating the surrounding tissue to maintain the bone’s width and height as the patient grows. Over time, the remaining root structure is naturally replaced by bone tissue through a process known as replacement resorption. This technique ensures the volume and contour of the jawbone are retained until the patient reaches skeletal maturity, providing a better foundation for permanent tooth replacement later on.
Understanding the Surgical Steps
The decoronation procedure begins with local anesthesia, followed by the careful elevation of a small, full-thickness gum tissue flap around the affected tooth. This flap allows direct access to the crown-root junction and the surrounding bone. Using a high-speed dental drill with specialized burs, the visible crown is cut away, usually just above the cementoenamel junction, where the enamel meets the root structure.
It is important during this step to remove all traces of the enamel to prevent issues with the overlying gum tissue healing properly. Once the crown is removed, the dentist addresses the remaining root structure, ensuring any existing root canal filling material is entirely removed. The root canal space is then thoroughly irrigated with a sterile solution and allowed to fill with fresh blood.
This introduction of a blood clot into the canal space encourages the subsequent integration of the root with the surrounding bone. The top surface of the remaining root is then reduced slightly below the level of the surrounding bone, typically by one to two millimeters. Finally, the gum tissue flap is repositioned and secured with fine sutures, completely submerging the root fragment below the tissue line.
Post-Procedure Care and Future Considerations
Immediately following the surgery, patients are advised to manage discomfort with over-the-counter pain relievers and maintain a soft diet for a few days to protect the surgical site. Careful oral hygiene is necessary to keep the sutures clean. The patient returns for a follow-up appointment to have the sutures removed and check on the initial healing.
The long-term consideration is replacement resorption, where the root is slowly dissolved and replaced by new bone tissue. This process can take several years, but the submerged root functions as an internal bone graft, maintaining the horizontal and vertical dimensions of the jawbone. Regular clinical and radiographic monitoring is necessary to track the root’s resorption and the continuous growth of the alveolar bone.
Once the patient has completed skeletal growth, typically in late adolescence, the site is ready for a definitive prosthetic solution. Because decoronation preserved the bone volume, the eventual restoration, such as a dental implant or a fixed bridge, can be placed with minimal need for additional bone grafting. This approach ensures a stable, aesthetic, and long-lasting replacement for the lost tooth.