Atypical odontalgia: an up-to-date view.

Atypical odontalgia (AO) is a little known chronic pain condition. It usually presents as pain in a site where a tooth was endodontically treated or extracted, in the absence of clinical or radiographic evidence of tooth pathology. It is a rare clinical challenge for most clinicians, which leads to the patients being referred to several specialists and sometimes undergoing unnecessary surgical procedures. The pain mechanisms involved in AO are far from clear, and numerous potential mechanisms have been suggested. Currently, the most accredited hypothesis is that AO is a neuropathic pain condition caused by deafferentation. The differential diagnosis of AO remains difficult, because it shares symptoms with many others pathologies affecting this area. Patients have difficulties accepting the AO diagnosis and treatment. As a result, they frequently change physicians, and may potentially also receive several invasive treatments, usually resulting in an aggravation of the pain. Although some patients do get complete pain relief following treatment, for most patients the goal should be to achieve adequate pain management. Currently, most management is based on expert opinion and case reports. More research and high quality randomized controlled trials are needed in order to develop evidence-based treatments, currently based on expert opinion or carried over from other neuropathic pain conditions in the orofacial region.