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Longitudinal analysis of deciduous tooth emergence: III. Sexual dimorphism in Bangladeshi, Guatemalan, Japanese, and Javanese children

Department of Anthropology, Center for Studies in Demography and Ecology, Center for Statistics and the Social Sciences, University of Washington, Seattle, Washington 98195, USA.
American Journal of Physical Anthropology (Impact Factor: 2.51). 11/2003; 122(3):269-78. DOI: 10.1002/ajpa.10239
Source: PubMed

ABSTRACT Previous studies, mostly in European populations, found sex differences in the pattern of deciduous tooth emergence. Most studies find that the anterior dentition in males is precocial relative to the female dentition, and the pattern reverses so that females lead males in the emergence of the posterior deciduous dentition. Less is known about sex differences in the dental development and emergence of non-European populations. Here we examine the pattern of sex differences in deciduous tooth emergence in Japanese, Javanese, Guatemalan, and Bangladeshi children. The data come from four longitudinal or mixed longitudinal studies using similar study protocols. Survival analysis was used to estimate parameters of a log-normal distribution of emergence for each of the 10 teeth of the left dentition, and sexual dimorphism was assessed by sex-specific differences in mean emergence times and by Bennett's index. The results support the pattern of developmental cross-over observed in other populations. We conclude that there is little evidence to support the hypothesis of Tanguay et al. ([1984] J. Dent. Res. 63:65-68) that ethnic factors mediate sex differences in the emergence of deciduous teeth.

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    • "Unfortunately , the summary statistics in the Anderson et al.'s publication are of questionable value because the authors used what Smith (1991b) has referred to as ''Method B.'' In ''Method B,'' interval-censored longitudinal data are analyzed by assuming that events occurred at the midpoint of the interval or evenly spaced within the interval if more than one event occurred within an observation window. This approach to analyzing interval-censored data is well known to be problematic (Lindsey and Ryan, 1998), and more appropriate methods are available that have been applied to longitudinal data on dental emergence (Holman and Jones, 1998; Parner et al., 2001; Bogaerts et al., 2002; Holman and Jones, 2003; Leroy et al., 2003; Holman and Yamaguchi, 2005; Yamaguchi and Holman, 2010). "
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