A hemisection is a dental procedure designed to preserve a portion of a damaged multi-rooted tooth when complete extraction is the only alternative. This technique involves the surgical division of the tooth and the removal of one compromised root along with the corresponding section of the crown structure. The goal is to eliminate a localized source of disease while retaining the remaining healthy tooth structure, which can then be restored for function and appearance. The remaining segment must have a healthy root and surrounding bone to support a final dental restoration.
When is a Hemisection Necessary
A hemisection is considered when damage is confined to only one root of a multi-rooted tooth, allowing the healthy portion to be saved. This procedure is most often performed on mandibular (lower) molars, which usually have two distinct roots. It serves as a conservative alternative to full tooth removal.
Severe localized periodontal disease causing significant bone loss around only one root is a frequent indication. Similarly, a vertical root fracture or a crack affecting just one root that cannot be repaired may necessitate this surgical division. The procedure may also be required when a root canal treatment has failed on one root, but the adjacent root remains healthy and structurally sound.
Saving a functional portion of the natural tooth structure is a major benefit. This helps prevent the bone loss that commonly occurs after a complete extraction and avoids the need for a bridge or a dental implant to fill the space.
Steps of the Procedure
The hemisection procedure begins with the administration of a local anesthetic. The surgeon makes a small incision in the gum tissue to expose the root structure and surrounding bone, allowing visualization of the affected root and the furcation (where the roots divide).
A high-speed dental handpiece is used to section the crown of the molar vertically down through the furcation. This division separates the portion of the tooth associated with the diseased root from the healthy remaining segment. The compromised root and the separated crown fragment are then extracted.
After removal, the surgical site is thoroughly cleaned, and the remaining healthy root is smoothed and reshaped. The exposed pulp chamber of the retained root is sealed to prevent future infection, and the gum tissue may be sutured. A temporary filling or crown is often placed to protect the remaining structure while a permanent restoration is prepared.
Recovery and Long-Term Outlook
Following the hemisection, patients can expect a healing period similar to a minor surgical extraction, with mild discomfort and swelling for a few days. Pain management involves pain relievers, and patients are advised to avoid chewing on the treated side. Maintaining good oral hygiene is important, requiring gentle brushing and the use of a prescribed antiseptic mouthwash to protect the healing site.
Dietary restrictions are temporary, focusing on soft or liquid foods initially before gradually reintroducing normal foods. A follow-up appointment is necessary to remove any sutures and monitor the initial healing.
The long-term success of the hemisection relies heavily on the subsequent placement of a final, custom-fitted crown. The crown stabilizes the structure, protects it from fracture, and restores its function. Hemisectioned teeth have a favorable prognosis, with success rates reported in the range of 80–90% over a five-to-ten-year period, provided the remaining root receives adequate root canal therapy and a proper final restoration. Longevity is also directly influenced by the patient’s commitment to daily oral hygiene and regular professional check-ups.