Forensic Dentistry, Second Edition

120 Forensic dentistry

while exposing the pulp chamber and radicular pulp system, predentin,
and dentin for DNA recovery.^41 Once the dentin has been removed from
the crown, the enamel shell and any restorations are left intact. Cases that
may require this approach are those that involve remains of unique cultural
value or museum specimens where the destruction of the material must be
minimized. Examples are investigations into the remains of Tzar Nicholas
and his family, analysis of dental evidence representing members of George
Washington’s extended family, and attempts to identify the putative skulls
of Mozart and Fredric Schiller (unpublished data). This technique is also
applied by the U.S. military in the identification of its missing in action (MIA)
soldiers and in mass fatality incidents in which individual teeth are recov-
ered and may represent the sole remains available for return to a family.^42
Attention is being given to other nondestructive methods, especially with
respect to ancient invaluable human exhibits. Studies by Krzyżańska use a
micro fluidic pump to flush cells from the tooth by rinsing the pulp system
from the apical orifices through small holes in the occlusal surface.^43 These
methods may show promise for forensic exhibits to allow DNA recovery from
the pulp while preserving the tooth.
Alternatively, following the application of traditional forensic odonto-
logical identification methods, Sweet recommends that crushing or grind-
ing the entire tooth into a fine powder can obtain the maximum quantity of
DNA.^44 This must follow adequate documentation of the exhibit with charts,
notes, photographs, and radiographs. The method allows recovery of DNA
from remnants of pulpal cells as well as the embedded cells present in the
hard tissues, especially in cold cases involving skeletal remains.
On a case-by-case basis, then, the laboratory must make informed deci-
sions about the best method to employ to recover DNA. This decision should
be made in concert with the forensic odontologist using his knowledge of
dental histology and taking into account the presence of any identifiable
morphological or restorative traits of the tooth.

7.6 Saliva and Oral Mucosa as Sources for Forensic DNA

In add it ion to bei ng consu lted on t he use of teet h a nd t he cra n iofacia l st r uc-

tures as a source for human identification, the forensic odontologist should

also be prepared to advise on matters concerning the biological character

of oral mucosal and salivary DNA for the same reason. Salivary DNA can

be recovered in a variety of scenarios and from a wide range of inanimate

objects, including clothing, foods, tobacco products, oral hygiene devices,

drink containers, dental prostheses, stamps, and envelopes. Laboratories

will generate their own protocols for recovery of salivary DNA from per-

sonal effects, but will probably defer to the odontologist in processing a