Biopsy Specimens

The vast majority of teeth are removed because of dental caries or periodontal disease and are not submitted for histological examination unless there are unusual clinical or radiological findings. Teeth adjacent to cystic lesions are removed either as part of the treatment for the lesion (e.g., the unerupted tooth associated with a dentigerous cyst) or because they cannot be restored to useful function (e.g., a tooth whose roots have been extensively resorbed by a keratocyst). Where a primary neoplastic lesion is suspected, teeth may be removed to provide access to underlying lesional tissue via the socket. Teeth may be submitted whole or as fragments; deeply buried unerupted teeth are most likely to be divided by the surgeon prior to removal.

Apicectomy is the removal of a short portion of the tooth root apex to control persistent peri-apical infection not responsive to non-surgical endodontic procedures. A flap of mucosa and associated periosteum is reflected to expose the area, the apical portion of the tooth is removed with a drill and the pulp canal opening sealed usually with amalgam. Soft tissues associated with periapical infection are removed en passant; most will represent a radicular cyst, apical granuloma or chronic dental abscess. Other benign-looking odontogenic lesions, such as small cysts or odontomes, will be accessed in a similar fashion, shelled out and the cavity curetted. The resulting specimens are usually submitted in total. Very large cystic lesions tend to be marsupialised rather than removed in total because of the risk of fracture or iatrogenic injury to nerves. A portion of the lining will be sampled, primarily to detect ameloblastoma, which requires more radical surgery than a keratocyst.

The close proximity of important anatomical structures in the jaws means that biopsy samples of primary bone lesions tend to be small. Benign-looking lesions will be removed in total, often as fragments, while suspected malignancies will be sampled to avoid compromising later definitive surgery. Accurate histological assessment often requires demonstration of the interface with normal bone so, in the mandible in particular, it is important to avoid sampling only the cortical bone. Access to lesional tissue is achieved either by reflecting a mucoperiosteal flap or extracting teeth in the region and using the sockets to expose the lesion. Biopsies are taken either as curet-tings or intact pieces removed with a drill or chisel.

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