When dental records are unavailable and other methods of identification are not possible, the forensic dentist can often produce a "picture" of the general features of the individual. This process is known as post-mortem dental profiling. A dental profile will typically provide information on the deceased's age, ancestry background, sex and socio-economic status. In some instances it is possible to provide additional information regarding occupation, dietary habits, habitual behaviors and occasionally on dental or systemic diseases.
The forensic dentist will often work with a forensic anthropologist to help in identification of an individual or the development of a profile from remains. The determination of sex and ancestry can be assessed from skull shape and form. Generally, from skull appearance, forensic dentists can determine race within the three major groups: Caucasoid, Mongoloid and Negroid. Additional characteristics, such as cusps of Carabelli, shovel-shaped incisors and multi-cusped premolars, can also assist in determination of ancestry. Sex determination is usually based on cranial appearance, as no sex differences are apparent in the morphology of teeth. Microscopic examination of teeth can confirm sex by the presence or absence of Y-chromatin and DNA analysis can also reveal sex.
In developing a profile dental structures can provide useful indictors to the individual's chronological age. The age of children can be determined by the analysis of tooth development and subsequent comparison with developmental charts. Conclusions are usually accurate to approximately ±1.5 years. While eruption dates can be used in determining sub-adult ages, these are highly variable and the actual developmental stages of the teeth are more accurate.
Other features can be useful in individualizing a profile. The presence of erosion can suggest alcohol or substance abuse, an eating disorder or even hiatus hernia while stains can indicate smoking. Unusual wear patterns may result from pipe stems, cigarette holders, hairpins, carpet tacks or previous orthodontic treatment. The quality, quantity and presence or absence of dental treatment may give an indication of socio-economic status or likely country of residence.
Because of the resistant nature of dental tissues to environmental assaults, such as incineration, immersion, trauma, mutilation and decomposition, teeth represent an excellent source of DNA material. When conventional dental identification methods fail, this biological material can provide the necessary link to prove identity.