Throughout the medical field, a biopsy is simply the removal of a tissue sample to determine if it is diseased. In dentistry, teeth and gums are sometimes sent for biopsy. The role of a biopsy in the dental industry is to diagnose oral cancer or other pathology. If your dentist sees an area that needs biopsied, you will be referred to an oral surgeon who can make the final determination if a biopsy will need to be done. When the pathology report is back, the two doctors will work closely together to determine if any further action is needed.
If you have unexplained lesions in your mouth, they need to be examined by a dentist. They may or may not be cancerous, but they need medical attention nonetheless.