A cervical tensor position, a type of examination in which a plain film is taken of the cervical spine, is not in a particular part of the body. In other words, if a patient sees a description of the cervical spine in the open mouth position, it means that the doctor is performing this type of imaging on the patient and is not describing a specific part of the patient’s body. Cervical open-mouth plain films are primarily used to observe the more upper cervical vertebrae, such as the atlas and the cardinal vertebrae. When flat films are normally taken, they are often obscured from view by the mandible in front of them, as well as the mastoid process on either side. If they are to be observed, the patient is required to open his or her mouth so that the rays pass backwards through the inside of the mouth, after which the images of these areas can be clearly shown. In general, an open-mouth view of the cervical spine is very likely to indicate a disturbance of the atlantoaxial relationship or a fracture. After this, the doctor can supplement the diagnosis with a CT or MRI.