Análise de tecidos dentais e materiais dentários submetidos a altas temperaturas: revisão de literatura

Abstract

Dental arch analysis is the most efficient method of forensic identification in adverse situations involving high temperatures. Thus, in the event of an individual's death, ante-mortem dental records can be used to compare with information obtained post-mortem and assist in the identification process. Thus, the aim of this study was to conduct a literature review on the behavior of dental tissues and dental materials submitted to high temperatures, in order to elucidate the main changes with forensic purposes. A bibliographic search was carried out in the Scielo, Pubmed, Medline and Google academic databases. The search words used were the following: "high temperature", "high temperatures", "dentistry", "forensic dentistry", "dental materials", "restorative materials", "restorative materials", "brackets", "brackets", "incineration", "incineration", "implants", "implants". The search was updated until March 2022, and articles published between 2006 and 2022 were selected. The materials analyzed included: teeth, zinc oxide and eugenol cement, glass ionomer cement, amalgam, composite resin, ceramic materials, intraradicular pins, orthodontic brackets and implants. Twenty-three articles were included. The study covers the main changes in teeth, glass ionomer cement, amalgam and composite resin observed at temperatures of 200 °C, 400 °C, 600 °C, 800 °C and 1000 °C. Regarding the other dental materials, the research contemplates the changes in zinc oxide and eugenol cement at temperatures of 200 °C and 800 °C, ceramic materials at 900 °C and 1000 °C, dental pins from 800 °C and implants from 1000 °C, and orthodontic brackets from 200 °C to 1200 °C. Finally, it is concluded that teeth start to change at 200 °C, and fragment at 1000 °C. Zinc oxide eugenol cement, when used for endodontic and restorative treatments, is lost at 800 °C. Glass ionomer cement at 200 °C loses its seal and is dislodged at 800 °C. Amalgam blisters on its surface at 200 °C, and either breaks up or remains intact at 1000 °C. Composite resin shows marginal shrinkage at 200 °C moving out of the cavity at 1000 °C. Ceramic materials initiate their changes at 900 °C. Furthermore, glass-fiber dental pins show changes at 800 °C, while titanium pins show slight thermal expansion. Implants maintain their structure up to 1000 °C, while orthodontic brackets maintain their structure up to 1200 °C.