284 • Alan H. Goodman 



It is not possible to rule out any of these processes. All may 

 contribute to the associations which we have observed. How- 

 ever, the wide variation in the degree of association between 

 stress and longevity supports the view that the association is 

 not solely a function of biological factors, since these sam- 

 ples appear to be genetically continuous (Cohen 1 974; Good- 

 man, Lallo et al. 1984). Furthermore, the greatest difference 

 between stressed and nonstressed group mean ages at death 

 occurs in the MM period. Since this is also the horizon in 

 which status differences are likely to be greatest (Rothschild 

 1979), these data suggest that lifelong differences in social 

 status, and therefore differential cultural buffering from 

 stress, may be important. Unfortunately, it is difficult to 

 assess cultural buffering in archeological populations. Good- 

 man, Rothschild, and Armelagos (1983) have tested to see if 

 differences in type of grave offering, an indicator of status 

 differences, might explain the association between stress and 

 longevity. While individuals with no grave goods are more 

 likely to have multiple hypoplasias (17.6%) as compared to 

 individuals with no nonutilitarian offerings (8.7%), their re- 

 lationship does not explain the association between hypo- 

 plasias and age at death. The inability of grave goods to 

 explain the observed association, however, is probably more 

 a function of their uncertainty as indicators of status than of 

 the insignificance of status differences in the etiology of 

 childhood stress and adult mortality. 



Although these data have largely been unable to distin- 

 guish among these mechanisms, it is suggested that a cultural 

 buffering hypothesis is most congruent with the pattern of 

 associations. Furthermore, this hypothesis is not exclusive of 

 a "biological damage" mechanism. Low status during child- 

 hood may promote disease and undernutrition which leaves 

 individuals less able to rally from future insults. Most impor- 

 tantly however, the data are strongly in support of the notion 

 that enamel defects are indicators of stress and that this stress 

 is highly meaningful in terms of life expectancy. 



Socioeconomic and nutritional correlates 

 of dental defects in contemporary 

 Mexican children 



The second study is part of the Collaborative Research Sup- 

 port Project, or CRSP. The purpose of CRSP is to understand 

 better the sequence and severity of functional effects of mild- 

 to-moderate undernutrition, the most prevalent but least un- 

 derstood form of malnutrition. The research site is in the 

 Tamascalsingo region of the Mexican highlands, about 170 

 km northwest of Mexico City. The immediate area, the Solis 

 Valley, includes 13 villages, 5 of which were included in the 

 study. Living conditions are "typical" for a rural community 

 in the Third World. Roads are unpaved and there is little 

 sanitation. Houses are small, usually consisting of from one 

 to three rooms. The dominant food item is tortillas, though 



this traditional food is rapidly giving way to pasta and coca- 

 cola. Relevant to this study, the fluoride content of the central 

 well's water is low, 0.20 ppm. 



The dental data are from 7-9-year-old children, targeted 

 for inclusion in the CRSP study, and their school age sib- 

 lings. The sample includes 3(X) children, ages 5 to 15, with 

 slightly more females than males. Defects were scored on 

 anterior teeth by developmental zones approximating sixths 

 of tooth crowns from the incisal to the cervical border. 

 Classification followed the FDI index of developmental de- 

 fects of dental enamel (1982). Five types of defects were 

 found from most to least prevalent: white opacities, generally 

 mild hypoplastic lines, hypoplastic pits, yellow opacities, 

 and missing enamel. In the permanent incisors most hypo- 

 plasias developed in the second to fourth zones, suggesting a 

 peak age at formation of from about 8 to 30 months. Hypo- 

 calcifications or opacities tended to occur in the first to third 

 zones. 



The following analysis includes only permanent dentition 

 defects, divided into two general classes — enamel hypocal- 

 cification, or all opacities, and enamel hypoplasias, or all 

 deficiencies in thickness. Patterns of association are pre- 

 sented between enamel defect and socioeconomic status and 

 height-for-age. Height percentiles were calculated relative to 

 National Center for Health Statistics Standards (Hamill et al. 

 1977). Socioeconomic status is based on household charac- 

 teristics and material wealth (Allen et al. 1987). 



Mean height percentile for those with no defect, with hy- 

 pocalcifications and with hypoplasias, by anterior tooth, are 

 presented in Figure 3. As is to be expected for a rural Mexi- 

 can sample, the mean percentile height-for-age is generally 

 low, around 10-15%. 



The pattern for incisors is of highest mean height percen- 

 tiles associated with opacities and the lowest with hypo- 

 plasias. For example, the hypoplasia group mean percentile 

 for the upper lateral incisor (3.1%) is significantly less than 

 either of the other groups (no defects = 12.3%; hypocalcifi- 

 cations = 17.9%). While this pattern varies slightly for the 

 other teeth it is clear that enamel hypocalcifications are not 

 associated with a reduced height-for-age and enamel hypo- 

 plasias are so associated. 



No significant mean differences in the socioeconomic 

 scores (SES) are observed for those with and without hypo- 

 calcifications (Figure 4). However, a consistent decrease in 

 SES is seen in those with hypoplasias versus those without 

 defects. This decrease in hypoplasia mean is significant at the 

 .05 level or greater for the upper central incisor, the lower 

 lateral incisor, the lower canines and the total. In sum, the 

 SES data are similar to the above stature data in that de- 

 creased SES is not associated with hypocalcification, but is 

 associated with the appearance of hypoplasias. 



The lack of association between enamel hypocalcifcations 

 and SES or nutritional status suggests that these defects are 

 not related to general conditions of life. This is consistent 



Zagreb Paleopathology Symp. l9iiH 



