Forensic dental identification 179
authors show this method of intraoral image comparison to be both objective
and reliable.^22
As stated earlier in this chapter, there is great demand for esthetic res-
torations in today’s dental environment. The frequent placement of esthetic
resin restorations in anterior and posterior teeth can further complicate the
ability to make a positive dental identification due to the possibility of the
forensic examiner being unable to identify a resin restoration clinically or
radiographically. Pretty et al. used quantitative light-induced fluorescence
(QLF) in the identification of dental composite resin in extracted teeth. They
further explored some of the difficulties encountered in the post mortem
examinations that include tooth-colored restorations. In Pretty’s study,
extracted and previously unrestored teeth were utilized. Resin restorations
were placed in half of the tooth specimens while the other teeth remained
unrestored. Digital photographs and QLF images were taken of the speci-
mens under both wet and dry conditions. Dental examiners were asked to
evaluate the images to determine if teeth were restored or unrestored. The
results of the study showed a significant improvement in the ability of the
examiners to identify restored surfaces when QLF was employed.^23
Hermanson et al. have demonstrated the usefulness of UV light in the
visualization of dental resins. The evaluation using visible light from the UV
spectrum is a qualitative method that can be used to locate esthetic resin
fillings or pit and fissure sealants that might otherwise go undetected on
clinical examination.^24
Bush et al. investigated the ability to identify specific dental restorative
resins by their formulation. Manufacturers’ formulations of dental resins dif-
fer with respect to filler particle size and elemental composition. Through the
use of scanning electron microscopy and energy-dispersive x-ray spectros-
copy, this study demonstrated that the makeup of dental resin materials is
potentially useful as an aid in dental identification cases. Through the evalu-
ation of several dental resins, they were able to determine that even under
conditions of extreme heat, the element composition of these products was
relatively unaltered. The data from this study were used to initiate the creation
of a database for use in identification of resin restorations in teeth through
the elemental analysis of their composition, and further reinforces the need
for the dental practitioner to maintain thorough written records regarding
specific materials used in tooth restoration.^25
The same team of researchers conducted an additional study to dem-
onstrate the utility of dental resin identification and the creation of a dental
resin database using portable x-ray fluorescence (XRF). This study again used
the evaluation of the elemental composition of dental restorative resins and
their ability to withstand high-heat conditions. Using XRF, the examiners
examined resins placed in cadavers both prior to and after the placement of
the cadavers in a crematorium. In both situations the study demonstrated the