Work

Thermal effects of molten brass exposure on human teeth and noble alloy metal–ceramic restorations: an experimental forensic study

Year: 2026

Type: article

Abstract: Dental and prosthetic structures are well recognized in forensic contexts for their contribution to the identification of human remains. In such scenarios, valuable information may be obtained from metal–ceramic crowns fabricated with noble alloys. Based on judicial cases involving the suspected disappearance of bodies in foundries, the aim of this study was to evaluate the behavior and structural changes of these restorations when exposed to elevated temperatures, with particular emphasis on exposure to molten metals, as may occur in industrial or metallurgical environments. This experimental study evaluated the thermal behavior of metal–ceramic crowns with noble alloys (gold–platinum–palladium) cemented on extracted human teeth. The study was conducted on 200 dental samples extracted for therapeutic reasons and subsequently analyzed under controlled experimental conditions. All extractions were performed exclusively for clinical indications, and all donors provided written informed consent for the scientific use of the extracted teeth, which were fully anonymized prior to experimentation. Samples were subjected to immersion in molten brass at 980 °C for predefined time intervals. Morphological integrity, structural alterations, and prosthesis–tooth interactions were assessed after thermal exposure. Noble alloy metal–ceramic crowns demonstrated high resistance to extreme temperatures, maintaining structural integrity despite surface oxidation and decementation of the prosthetic component.. Dental roots showed variable degrees of preservation, with identifiable morphological features remaining detectable even after prolonged exposure. The tooth–prosthesis complex exhibits significant thermal resistance under extreme thermal exposure conditions comparable to those encountered in metallurgical environments. These preliminary findings suggest that noble alloy metal–ceramic restorations may represent potential forensic markers and may contribute to personal identification under thermal conditions comparable to those investigated in the present study.

Source: Scientific Reports

DOI: 10.1038/s41598-026-66595-x