Forensic Dentistry, Second Edition

286 Forensic dentistry

13.4.4 Tooth Wear
Occlusal attrition has been a characteristic feature of adults’ teeth throughout
time; it is only recently in industrialized countries that grit (and grit size) has
been reduced to the point that attrition is now trivial. Rates of tooth wear are
intimately associated with diet, particularly food preparation processes.14 0,141
The amount of occlusal attrition is proportional to a person’s age (i.e., the
duration of time a tooth has been functioning), but the rate of wear varies
tremendously among cultures, so age needs to be tied to the appropriate food
processing context.
Murphy^141 was among the first to develop a tooth wear grading system
that accounted for morphologies of the individual tooth types as well as using
enough grades to approximate a continuous scale (also see Molnar, 1971^142 ;
Scott, 1979^143 ). Figure 13.5 illustrates the tooth-specific scheme developed
by Smith. Smith’s scheme is individualized for the different tooth ty pes, and
ranges from traces of wear (polished or small facets on the enamel) to loss

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Molars Premolars

Incisors &

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Figure 13.5 the tooth wear ordinal scheme developed by smith.^94 the system
accounts for different tooth types. Grade 0 (not shown) would be a pristine, com-
pletely unworn tooth. multiple examples connected by horizontal lines show
the ranges of variation within a grade. while the grades are numbered, this is an
ordinal, morphological system; one cannot assume the grades are equally spaced.