Hypoplastic area method for analyzing dental enamel hypoplasia

Abstract

Most analyses of dental enamel hypoplasia compare frequencies of disturbed tooth types, which do not account for variability in the area of affected enamel. An alternate methodology, hypoplastic area, is presented here that accounts for this variability by combining acute and continuous enamel hypoplasia into an interval-level variable. The method compares samples based on individuals, by multiple tooth type variables, or by a single value rather than by tooth types. Use of the hypoplastic area method is illustrated by analyzing human skeletal dentitions in three archaeological samples: Meroitic Nubians from Semna South, Sudan; Anasazi from Navajo Reservoir, New Mexico; and Mogollon from Grasshopper Pueblo, Arizona. Both univariate and multivariate statistical tests are employed to assess variation in defects between individuals and samples. By incorporating measurements of continuous defects, the hypoplastic area method provides information beyond that of frequency data in comparing levels of stress. Flexibility of the method is also discussed.

An inter-site comparison of enamel hypoplasia in bison: implications for paleoecology and modeling Late Plains Archaic subsistence

“…Each hypoplasia was measured from its lowest point to the CEJ, to the nearest 10th of a millimeter. A similar technique was applied to suid molars [13] and by anthropologists on human teeth [18,26]. In the case of dents or pitting, the center of the hypoplastic area was used as a measuring point.…”

“…Research on human teeth shows that deficiency in enamel thickness is exhibited as abnormal topography in the form of lines, dents, or pits [18].…”

Correspondence between enamel hypoplasia and odontometric bilateral asymmetry in Australian twins

“…In keeping with Blakey and Armelagos (1985), Hutchinson and Larsen (1988), Larsen and Hutchinson (1992), and especially Ensor and Irish (1995), hypoplasia width was ranked as a separate variable in stages of absent, present but less than 1 mm, between 1-1.5 mm, between 1.5-2 mm, and just one case of Ͼ2 mm as judged by a handheld magnifier with a reticle. Vertical hypoplasia width may relate to duration of metabolic insult, although hypoplastic area might be a more revealing measure (Hoover, 2001).…”

An Investigation of Dental Health in the Migration Period: A Case Study from Prague-Zličín, Czech Republic

“…In the case of dental enamel hypoplasia being detected, the type of hypoplastic defect was determined according to the DDE index: lines (FDI type 4: L-lines, G-grooves); pits (FDI type 3: Ps-pits, Pl-pit line); and chronic enamel hypoplasia (i.e. "pit patches" and "continuous chronic enamel hypoplasia") (Santos, Coimbra 1999;Goodman et al 1992;Goodman, Rose 1990;Ensor, Irish 1995;Sarnat, Schour 1941;Corruccini et al 1985;Littleton 2005;Obertová 2005;Jarošová et al 2012, etc.). Lines and pits are classified in this paper as acute DEH (A DEH).…”