Biopsy is a simple surgery that removes sample of the soft tissue or bone from the body. In case of a dentist, this may be gum tissue, tooth or a jaw piece. Biopsies are performed when a dentist of physician want to take a look at the sample in the laboratory. The goal is to find the sources and abnormalities of the lesions. They may be caused by illness or injuries. The lesions may be in the area of soft tissue or bone that looks abnormal.