Background: Dentists need to be aware of the relationship between malignancies and paresthesia or complete loss of sensation in a jaw segment. In particular, dentists should be aware of numb chin syndrome (NCS) and its clinical manifestations, as well as the limitations of using panoramic radiographs to detect the causative malignancy.
Case description: The authors report two cases of paresthesia in the mental region. No lesions were readily apparent on the patients' panoramic radiographs. To exclude the presence of disease in the mandible that could have been responsible for the NCS, the authors obtained computed tomographic (CT) images. They identified metastases to the mandible from primary malignant tumors elsewhere in the body.
Clinical implications: To prevent misdiagnosis of NCS, dentists need to be aware of the clinical manifestations of NCS, the need for CT imaging, the shortcomings of panoramic radiographs and the value of obtaining detailed and accurate medical and dental histories from patients.