Diagnosis is the process of finding out what is the problem. Dentist will usually ask a series of questions related to symptoms you may be experiencing, such as pain, sensitivity, discomfort etc. A dentist will look for signs such as swelling, redness, discolouration or anything else out of the ordinary. Combining this informtion and any other investigations such as xrays or scans, a diagnosis will be determined. Once a diagnosis is found, a treatment or plan can be discussed.