Histogical changes in oral mucosa (gingiva) as a method for estimating post-mortem interval: A literature review

Estimating the post-mortem interval (PMI) is an essential step in forensic investigations, particularly those involving homicides and unwitnessed deaths. However, traditional methods occasionally yield inconsistent estimates. Histological and molecular techniques are considered crucial in forensic pathology and are frequently employed to estimate the time interval of death. The gingiva is an oral mucosal tissue used to estimate PMI. This review aimed to examine the potential of histological methods to determine PMI using oral mucosal tissue, namely the gingiva, and to investigate changes that occur in oral mucosal tissue at different time intervals when compared with those in normal tissues. The oral mucosa comprises layers of stratified squamous epithelium and connective tissue. Similar to other body tissues, changes are known to occur in the gingiva after death, and these cellular and tissue changes should also be considered. Alterations in the gingiva include homogenisation, karyorrhexis, pyknosis, karyolysis, chromatin clumping, eosinophilia, collagen fibre degradation, and the loss of tissue architecture. Reviews collating the results of original trials have consistently reported how the oral mucosa is altered by autolysis and how such changes can be observed in histological tissue morphology after death. Histology is an acceptably accurate technique for estimating PMIs.