Resection Specimens

Resection specimens of maxilla for neoplastic processes include maxillary alveolectomy, palatal fenestration (also known as partial maxillectomy), maxillectomy (also known as hemimaxillec-tomy) and radical maxillectomy (also known as extended maxillectomy). Maxillary alveolectomy is indicated when a small tumour of the alveolar mucosa encroaches on or invades for a short distance into the bone. The resection lies within the alveolar process and does not involve the maxillary sinus. Palatal fenestration is performed for relatively localised tumours of the upper alveolar mucosa or floor of the maxillary sinus. The specimen comprises a portion of unilateral maxillary alveolar bone and alveolar mucosa, the opposing mucosa on the floor of maxillary sinus with a minimum of the medial and lateral sinus walls. Tissue from the upper buccal sulcus and a portion of the palatal vault may be included. Maxillectomy is indicated for larger tumours of the maxillary sinus and mouth that involve all or part of the maxillary sinus. There are a number of modifications but the specimen includes all of the maxillary alveolar bone from the midline to the tuberosity, bone from the lateral and medial walls of the maxillary sinus are included at least to the level of the zygomatic buttress. The orbital floor may be included or left intact. Radical maxillectomy is indicated for tumours extending beyond the confines of the maxillary sinus into adjacent sites. The specimen includes the orbital floor, orbital contents or pterygoid plates and muscles with the maxillectomy.

Resection specimens of mandible for neoplastic processes include rim resection (also known as marginal mandibulectomy) and hemimandibulectomy (also known as segmental mandibulec-tomy). Rim resection is performed for tumours of the lower alveolus or floor of mouth mucosa where there is minimal invasion of bone. If teeth are present the line of excision passes below their apices, often including the inferior alveolar canal. If the ascending ramus is involved, the excision line may include the coronoid process. Hemimandibulectomy is indicated for extension of mucosal tumour into the cancellous bone of the body of the mandible either from the alveolar aspect or from the buccal or lingual cortical plates such that preservation of sufficient bone at the lower border to prevent stress fracture cannot be achieved. Reconstruction is facilitated by preserving as much bone as possible, consistent with clearance. However, if there is a risk of perineural spread of tumour within the mandible, a block of bone containing the entire inferior alveolar canal is excised from lingula to mental foramen. Ameloblastomas and other locally aggressive odontogenic tumours in the mandible usually require hemimandibulectomy; there is little risk of perineural spread so the excision can be less radical.

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