Keywords

The jaw consists of the mandible (lower jaw) and maxilla (upper jaw), anchoring the teeth and articulating with the skull through the temporomandibular joints. Among the developmental disorders, hemimandibular elongation/condylar hyperplasia is the most important abnormality, where SPECT/CT can play an important role in diagnosis and therapy guidance. Osteomyelitis and osteonecrosis of the jaws, caused by dental infection, bisphosphonates, or radiotherapy, are difficult to treat, and SPECT/CT might help for diagnosis, staging of the extent of the disease, and guiding surgery and can be used for therapy response assessment besides conventional imaging modalities. Benign bone lesions like fibrous dysplasia can occur in the jaws and should be interpreted correctly to avoid overtreatment or unnecessary biopsy. Degenerative and arthritic changes can affect the temporomandibular joint. Benign and malignant primary bone tumors like osteosarcoma and metastases can involve the jaw bone. In the next chapters, we discuss all these jaw pathologies illustrated by multimodality case examples and focus on the value and characteristic features in SPECT/CT imaging. It is important to know the typical surgical procedures performed for the treatment of jaw diseases like condylectomy in hemimandibular elongation or decortication with grafting in osteonecrosis for the correct interpretation of the images.