**2. Biopsy: rationale**

When a patient with a particular lesion is seen, a list of differential diagnosis is formulated, and biopsy is useful at arriving at a definitive diagnosis or to confirm the clinical diagnosis. Oral biopsy was and still is the gold standard for oral diagnostic procedures. It is an invasive procedure with procedural limitations and a psychological effect on patients. It is important that the biopsy specimen be a true representation of the entire lesion. A carefully selected area involving normal as well as pathologic areas can produce good diagnostic specimen.
