The aim of this article is to provide an overall view of the literature available about “Poisons” and changes in oral cavity due to poisons.“Oral Cavity” is the first source to identify or analyze the poisonous features and different manifestations observed in postmortem.“Forensic Odontologists” here plays a major role to provide the oral manifestations and diagnosis. The oral cavity can be considered as a region with tremendous potential especially in regard to coming to a final forensic diagnosis. This article revolves around this concept and reviews the different manifestations in the oral cavity observed in post mortem.