150 Forensic dentistryreported by the hard tissues, those that do affect the skeleton or dentition rep-
resent t he most endu r i ng k i nd of ev idence. Ha rd t issue i nju r ies a re desig nated
as antemortem, perimortem, or postmortem according to time of occurrence.8.2.7.1 Antemortem Trauma and Pathology
Antemortem injuries and diseases will often be of use as identifiers (see above).
The classic examples are oral or orthopedic pathologies and their respective
treatments, prostheses, etc. Certain chronic disorders, e.g., rickets , DISH
(diffuse idiopathic skeletal hyperostosis; Belanger 2001, 258–267),^64 advanced
rheumatoid disease, etc., which exhibit skeletal facies, are also valuable in
individualization when these have been noted in the medical history of a
suspected match. Some chronic antemortem conditions may extend to the
end of life, and on a few occasions, may even contribute to death. Obviously,
such findings assume added importance when a clear cause of death can-
not be shown. A skeleton with a pacemaker beneath the disarticulated bones
of the thorax was recently encountered by the author. Subsequent tracking
of the serial number identified an elderly decedent with a long history of
cardiovascular disease. Though not as diagnostic as an atheromatous set of
coronary arteries in the hands of a pathologist the day after death, the find-
ing suggests, at least, a contributing cause. Although one occasionally finds
old projectiles (bullets, shotgun pellets, etc.) embedded in the skeleton, most
traumatic antemortem injuries will have been due to blunt force since one is
more apt to survive these than blade or firearms assaults.8.2.7.2 Perimortem Trauma
Perimortem injuries are those that occur at or near the time of death and
are most likely to be associated with the true cause of death. Accordingly,
such injuries become a critical focus. The most frequently encountered fatal
perimortem defects are induced by gunshot, blade, or a blunt object forcibly
applied. Each of these produces more or less characteristic defects. As a
two-phase material (calcium hydroxyapatite and collagen), bone withstands
compression and stretch. Under slow loading of force, the struck surface
compresses while the opposite side stretches. Because bone is weaker under
tensile forces, the stretched side fails first, often producing concentric cracking
(as in the flat bones of the skull) or concoidal (wedge-shaped) fracture lines
emanating from the point of failure. Under rapid loading (as in a bullet
strike), the bone responds as a brittle material. In the latter instance one may
see radiating cracks across the bone surface, or none at all.^55
Gunshot injury: The rules for interpretation of gunshot wounds (GSWs)
in hard tissue differ somewhat from those in fleshed cadavers. In
most instances, given an adequate sample of remains, one should be
able to determine (1) entry and exit sites, (2) the approximate angle