282 Forensic dentistry
under study.4,94 Rates of wear developed for one cultural group may
have no relevance to others.
- Periodontosis. Two unrelated issues are confounded here. Destruction
of the gingival, periodontal, and alveolar tissues may develop due
to pathogens—acute infectious diseases. These often rapid destruc-
tive processes have to be distinguished from “continued eruption,”
in which teeth continue to erupt, albeit slowly, throughout much
of life.95,96 Danenberg et al. have shown that the distance from the
cementoenamel junction (CEJ) to the bony alveolar crest increases
as people age.^97 Continued eruption seems to be an accommodation
to occlusal wear that, over time, reduces crown height. Continued
eruption helps to extend a tooth’s functional longevity. In contempo-
rary peoples, with trivial wear, the effect is simply to increase lower
face height.^98
- Secondary dentin. The slow age-progressive deposition of second-
ary dentin diminishes and ultimately occludes the pulp chamber.^99
Secondary dentin needs to be distinguished from tertiary dentin that
is thought to accumulate in response to caries and trauma.^100 Pulp
dimensions can be assessed radiographically, especially if computer-
assisted methods for enlargement and measurement are available.
Precision is required if teeth are sectioned so as to find and preserve
the maximum dimensions of the pulp chamber. Kvall et al. reported a
method in 1995 that allows estimation based on morphological mea-
surements of two-dimensional radiographic features of individual
teeth.^101 Earlier similar studies had reported unsatisfactory results.^102
The Kvaal method is less discriminatory than other methods but has
the important advantages of being noninvasive, not requiring extrac-
tion of teeth, and being useful for examination and regression anal-
ysis of all data performed, with age as the dependent variable. The
measurements include comparisons of pulp and root leng t h, pulp and
tooth length, tooth and root length, and pulp and root widths at three
defined levels. Vandevoort et al. reported a morphometric method
pilot study using microfocused computed tomography to compare
pulp-tooth ratios.^103 C a mer iere et a l. proposed a met hod i n 2 0 0 4 u si ng
pulp-tooth ratios of second molars.^104 In 2007 Berner et al. reported
a larger clinical trial of the Kvall method showing similar results.^105
Adetona et al. presented in 2008 a three-dimensional method using
cone beam computed tomography (CBCT).^106
- Cementum apposition. The thickness of cementum often increases
on roots with age, and cementum generally is thinnest near the CEJ
and thickest on the apical third of the root. Recent attention has
focused on cementum annulations—the deposition of a new layer of
cementum onto roots in a manner analogous to the growth of tree
