The Cementoenamel Junction: Gap, Overlay and Edge to Edge Relationships

The purpose of this research is to examine mineralized tissue relationships at the cementoenamel junction in the maxillary central incisor and the mandibular canine. There are three distinct relationships at the cervical region of the tooth: a gap junction is when the cementum and enamel fail to connect, an edge-to-edge when the cementum and enamel meet and an overlay when the cementum extends on to the enamel. There are four main research questions that have been addressed in this investigation; 1) Can a type of junction be correlated to racial affinity? 2) Is there a relationship between sex and junction type? 3) Is there a significant difference between adults and children? 4) Does dental hygiene or exposure to the oral cavity cause changes or damage to this structure? Population samples were utilized from a modern, historic and prehistoric time periods to address the above questions. Thin sections were analyzed at a magnification of 125X. The results verified a strong relationship between racial affinity and junction type. Sex was correlated to junction type on the labial surface of the canine only, while age and junction type showed positive statistical results for the both labial and lingual incisor. Dental hygiene and exposure (via age) to the oral cavity does not seem to result in a significant change at the cervical margin of the tooth. The goal of this research was to aid physical/forensic anthropologist in determining a biological profile of unknown individuals.