Unicystic Jaw Lesions: A Radiographic Guideline

I treat and he cures—the common saying is true. But his curing and our treatment undoubtedly depend on one factor and that is proper diagnosis. For proper diagnosis of any case in dentistry, radiographs play a very important role. Radiographs have been regarded as an invaluable boon to mankind giving him a 6th sense. It forms a necessary component of comprehensive patient care.5 Radiographs enable the dental professional to identify many conditions that may otherwise go undetected and to see conditions that cannot be identified clinically. An oral examination without dental radiographs limits the practitioner to what is seen clinically, the teeth and soft tissues. With the use of dental radiographs, the dental radiographer can obtain a wealth of information about the teeth and supporting bone.7 Adequate use of diagnostic aids and careful observation will clinically help the dentist to arrive at a proper diagnosis and render quality treatment to patients.9 Many lesions that occur in the jaw have a similar radiographical appearance and it is often difficult to differentiate among them. Despite development of various cross-sectional imaging modalities, the radiograph still remains the first and the most important investigation. Radiographic evaluation of jaw lesion characteristics, which includes location, margin, density, relation to tooth along with knowledge of clinical data, generally helps in narrowing the differential diagnosis. Jaw bone lesions especially unilocular ones, are difficult to diagnose because of their similar radiographic appearance.1 Any jaw lesion should be evaluated taking into consideration the following radiological features.2 1. Density of lesions, Margin, and locularity: Majority (>80%) of jaw lesions are radiolucent. Unilocular radiolucent lesions with well-defined boarders usually indicate a slow proliferating benign process. 2. Anatomical location, relation to dentition: Certain lesions have a predilection for a particular site, whereas others can occur anywhere in the jaw. Nonodontogenic lesions usually have no specific relationship to the dentition or can involve the bone around two or more teeth whereas odontogenic lesions typically involve only one teeth or a specific part of the tooth. 3. Cortical integrity, periosteal reaction and soft tissue: Slow growing lesions often cause expansion with cortical bowing while cortical destruction denotes aggressive inflammatory or neoplastic lesions. 4. Effect on surrounding structures: Evaluating the effect of a lesion on the surrounding structures help in inferring behavior of the lesions. If a lesion involves only one tooth, it is important to note the degree of tooth development, relationship of the lesion with portion of tooth. (Crown vs root vs entire tooth) and any signs of tooth resorption. The term ‘space occupying’ is used to describe a lesion that slowly creates its own space by displacing teeth and other surrounding structures. Resorption of teeth usually occurs with a more chronic or slowly growing process. The presence of reactive bone at the periphery of a lesion, whether corticated or sclerotic, usually signities slow, benign growth and possibly the ability to stimulate osteoblastic activity in the surrounding bone.