Abstract
Formalin is a hazardous chemical, yet it is the choice of fixative for diagnostic pathology. Dental surgeons routinely use formalin for preservation of oral biopsy specimens. Literature search revealed that during regular biopsy procedures, unintentional injection with formalin has occurred, and such rare seven cases have been reported till date. In addition to the literature review, the present article describes first case of accidental local infiltration with formalin into the buccal mucosa during a biopsy procedure, its damaging effect on the oral tissues, subsequent judicious management of the patient and successful tissue reconstruction with collagen membrane.