Kira Teppett-Higgs

Forensic Science
Gwyddoniaeth Fforensig

An investigation into the structural degradation of Bos Taurus teeth after exposure to high temperatures as an aid to dental remain examination in arson cases.

Mae ymchwiliad i ddirywiad strwythurol dannedd Bos Taurus ar ôl dod i gysylltiad â thymheredd uchel fel cymorth i archwilio gweddillion deintyddol mewn achosion o losgi bwriadol.

This study was conducted to assess the morphological and colour differences that happen once teeth have been exposed to extreme temperatures. If the results obtained are all supported by the previous research in this field, a scale can be created based on the colour of teeth to determine the temperature in which they were exposed. Due to current legislature, human analogues were used for this experimentation in the form of Bos Taurus teeth. After thorough research, bovine teeth were the superior decision as their similarities to human teeth were far closer than other mammals commonly used in scientific research. A methodology was created to analyse these changes at different temperatures. The teeth were microscopically analysed before and after incineration at 100C, 300C, 500C, 700C and 1000C for a duration of 10 minutes. Teeth are the hardest substance in the human body, and in this study they were seen to maintain most of their integral structure up to 700C. The literature review undertaken revealed that macroscopic alterations in heat treated teeth can be influence by a number of external factors, therefore microscopic alterations were examined as they provide a more accurate depiction of the temperature of exposure. The data collected suggests that further study is needed before creating the colour scale proposed as anomalies in this studies results, such as the presence of unexplained black pinholes clustered in the roots, means that further experimentation must be completed before attempting to create a universal colour scale for burnt teeth.

Cynhaliwyd yr astudiaeth hon i asesu'r gwahaniaethau morffolegol a lliw sy'n digwydd unwaith y bydd dannedd wedi'u hamlygu i dymheredd eithafol. Os yw'r canlyniadau a gafwyd i gyd yn cael eu hategu gan yr ymchwil flaenorol yn y maes hwn, gellir creu graddfa yn seiliedig ar liw dannedd i bennu'r tymheredd y cawsant eu hamlygu iddo. Oherwydd y ddeddfwriaeth bresennol, defnyddiwyd cyfatebiaethau dynol ar gyfer yr arbrofi hwn ar ffurf dannedd Bos Taurus. Ar ôl ymchwil drylwyr, dannedd buchol oedd y penderfyniad gwell gan fod eu tebygrwydd i ddannedd dynol yn llawer agosach na mamaliaid eraill a ddefnyddir yn gyffredin mewn ymchwil wyddonol. Crëwyd methodoleg i ddadansoddi'r newidiadau hyn ar dymheredd gwahanol. Dadansoddwyd y dannedd yn ficrosgopig cyn ac ar ôl llosgi ar 100C, 300C, 500C, 700C a 1000C am gyfnod o 10 munud. Dannedd yw'r sylwedd caletaf yn y corff dynol, ac yn yr astudiaeth hon gwelwyd eu bod yn cynnal y rhan fwyaf o'u strwythur integrol hyd at 700C. Datgelodd yr adolygiad o lenyddiaeth a gynhaliwyd y gall newidiadau macrosgopig mewn dannedd sy'n cael eu trin â gwres gael eu dylanwadu gan nifer o ffactorau allanol, felly archwiliwyd newidiadau microsgopig gan eu bod yn dangos tymheredd amlygiad yn fwy cywir. Mae'r data a gesglir yn awgrymu bod angen astudio ymhellach cyn creu'r raddfa liw sy’n cael ei chynnig gan bod anghysondebau yng nghanlyniadau’r astudiaethau hyn, megis presenoldeb tyllau du heb esboniad wedi'u clystyru yn y gwreiddiau, yn golygu bod yn rhaid cwblhau arbrofion pellach cyn ceisio creu graddfa liw gyffredinol ar gyfer dannedd wedi llosgi.