Forensic odontology
A joint meeting-the first to be held between the Forensic Science Society and the British Association of Forensic Odontologists-took place at Badock Hall, University of Bristol on 819 April 1988. The meeting was well attended, full of interest, and valuable in promoting professional and social contact. The three sessions of papers were chaired by Mr P Millen, Professor B Knight and Mr L Ciapparelli. The following report was prepared by Jacalyn Skinner.
An update on the estimation of age from teeth Mr JG Ritchie, General Dental Practitioner
This paper underlined the importance of teeth in the estimation of age as an aid to identification but cautioned that variations between individuals limited the accuracy obtainable. A detailed description was given of the four bouts of activity in the developing teeth, beginning with the appearance of the neo-natal line caused by a disturbance in calcification at birth and ending with the eruption of the wisdom teeth and the onset of tooth decay. Radiographic and visual studies of tooth development were first recorded in 1941. Tooth formation was divided into fourteen stages extending up to about age twenty-one when characteristic deterioration began. Other studies concentrated on six features of the tooth which altered as the tooth aged, including pulp cavity size, wear of the incisal edge, microscopical changes in cement, etc. Points were awarded for the features observed and the total was related to the subject's age. Age has also been estimated from tooth colour but this was not at all reliable. A technique recently introduced in the USA suggests that tooth age may be calculated from the degree of racemisation of amino acids in tooth proteins. Only the L-form can be dealt with by human metabolism and the extent of the consequent racemisation process therefore relates directly to protein age and indirectly to tooth age. However, racemisation is temperature-dependent and so a constant body temperature must be assumed. The rate is also affected by certain trace elements and further work is required to quantify this effect and also to improve the protein extraction technique.
Histological studies of bruising in human bite marks Dr DK Whittaker, Reader in Oral Biology, University of Wales
A case of murder and rape was reported in which crucial evidence centred around a possible human bite mark on the left nipple. The marks were hidden by lipstick and were not noticed at first examination of the body. By the time they were seen by a forensic dentist, the body had been frozen (-16ยฐC) and thawed twice. To confirm a bite mark it was judged necessary to demonstrate epithelial damage, oedema and bruising in histological section. However, the effect of freezing was to lyse the erythrocytes so that standard histological staining techniques were ineffective. Success in pinpointing the haem breakdown products was nevertheless obtained using the sensitive but carcinogenic reagent benzidine. A range of controls was similarly tested. The now-confirmed bite mark showed several features of interest and models