Hemisection-hope for last survival.

Sir,

A 26-year-old male patient reported with complaint of intermittent pain and sensitivity in left mandibular first molar since 3 months. Previously, endodontic treatment of same tooth was done 1 year back. But since then, he had no problem. On examination, the tooth was sensitive to percussion and no mobility was present. On probing the area, there was a 13 mm deep periodontal pocket around furcation area of the tooth. The preoperative radiographic examination showed badly perorated furcation area and extruded temporary cement through that which subsequently leads to extensive vertical osseous destruction of that region. A through and through defect was noticed in furcation region with Nabers's probe. In treatment plan, it was decided to remove the distal root after completion of endodontic therapy of the tooth. The working length was determined and canals were biomechanically prepared using step back technique in mesiobuccal and mesiolingual canals. The canals were obturated with gutta percha and resin-based sealer using lateral condensation method. The chamber was filled with glass ionomer cement to maintain a good seal and allow interproximal area to be properly contoured during surgical separation. Under local anesthesia, full thickness flap was reflected after giving a crevicular incision from first premolar to second molar. On exposure of surgical site, the bony defect along furcation area became quite evident. All chronic inflammatory tissue was removed with curets to expose the bone. The vertical cut method was used to resect the crown. A long shank tapered fissure carbide bur was used to make vertical cut towards the bifurcation area. A fine probe was passed through the cut to ensure separation. The distal root was extracted and the socket was irrigated adequately with sterile saline to remove bony chips and filling material debris. The furcation area was trimmed to ensure that no spicules were present to cause further periodontal irritation. Scaling and root planning of root surfaces, which became accessible on removal of distal root was done. The extraction site was irrigated and debrided. The flap was then repositioned and sutured with 3/0 black silk sutures. The occlusal table was minimized to redirect the forces along the long axis of mesial root. The case was followed up for 8 months for survival of resected molar. A fixed bridge was fabricated using adjacent 2nd molar and the resected molar as abutments to replace edentulous area [Figure 1].

Figure 1

Preoperative, intraoperative, and postoperative photograph of the case

Hemisection represents a form of conservative procedure, which aims at retaining as much of the original tooth structure as possible. The results are durable, and success rates are high if certain basic considerations are taken into account.[1] Periodontal, prosthodontic, and endodontic assessment for appropriate selection of cases is important. Success of root resection procedures depends, to a large extent, on proper case selection. Buhler stated that hemisection should be considered before every molar extraction,[2] because it provides a good, absolute, and biological cost saving alternative with good long-term success. A guiding principle should be to try and maintain what is present.[3] Hemisection has been used successfully to retain teeth with furcation involvement. However, there are few disadvantages associated with it. As with any surgical procedure, it can cause pain and anxiety. Root surfaces that are reshaped by grinding in the furcation or at site of hemisection are more susceptible to caries. Failure of endodontic therapy due to any reason will cause failure of the procedure. Unfortunately, a restoration can contribute to periodontal destruction, if margins are defective or if nonocclusal surfaces do not have physiologic form. Also, an improperly shaped occlusal contact area may convert acceptable forces into destructive forces and predispose the tooth to trauma from occlusion and ultimate failure of hemisection. In the case reported, various aspects of occlusal function such as location and size of contacts and steepness of cuspal inclines were considered seriously before prosthetic treatment. During treatment, occlusal contacts were reduced in size and repositioned more favorably. The keys to long-term success include thorough diagnosis, selection of patients with good oral hygiene, careful surgical and restorative management. Hemisection may be a suitable alternative to extraction and implant therapy and should be discussed with patients during consideration of treatment options.[4] The results obtained with this tooth offer possibility of a successful repair technique for this otherwise hopeless complication of endodontic therapy. To conclude, we recommend hemisection as a treatment option to conserve tooth structure and use it as an abutment. The prognosis of root resected molars may not be as grim as previously believed; rather such teeth can function successfully for long periods. It is thus a conservative option with acceptable prognosis.