Application of ultrasonography in dentistry

Summary development of the ultrasonography (US) equipments enables the visualization of fine detail of the surface structure of the face and neck soft tissue. In this article, some studies referring to the clinical usefulness of the US in dentistry in the diagnosis of lymph node metastases, tongue carcinomas, periapical lesions and temporomandibular joint disorders are reviewed. For the early detection of lymph node metastases, follow-up US is recommended at an interval of no more than 1 month if a “wait-and-see” policy is adopted. US-elastography has a potential to be a promising method offering complementary information to conventional US. In order to determine the appropriate treatment planning of tongue carcinoma (including the prediction of subsequent lymph node metastases), intraoral US should be routinely used as one of the standard technique for the evaluation of the depth of tumor invasion. In the diagnosis of periapical lesions, US can provide useful information about the extent of the lesions and the location of the tooth root apices once the surface cortical bone around the lesion is eroded. Moreover, US is reported to be useful as an alternative imaging technique for visualization of disk position, joint effusion and bone abnormalities for the evaluation of temporomandibular joint disorders.