Family Studies of the Facial Complex

Abstract

Although genetics has led to new ways of thinking about many problems in dentistry, there are others for which the concept of a particulate gene has failed to provide a clearcut solution. Interest in dentistry is not only in those discrete differences that may be attributed to a single gene substitution but also in such compound characters as arch shape, tooth morphology, or facial bone relationships that differ among individuals. Study of the variation in such quantitative dental characters has been limited largely to twin studies' 2 and to the comparison of mean values among groups of individuals.3-6 In these studies several or many different measurements of dental characters were made and were treated as independent of each other, although it was generally recognized that such treatment disregards the correlations resulting from those common causative agents that affect the various examined characters. It is clear that such analyses cannot provide a true picture of the relationships among the different groups under study.During recent years the analysis of intercorrelated compound variables has attracted the attention of many statisticians. Powerful analytical methods have been devised for comparing and for testing the significance of differences between multivariate distributions and for examining and describing the interrelationships among the variables contributing to such distributions. Until recently, these methods have been used in anthropologic and biologic research by comparatively few workers. Both biologists and statisticians have, however, recognized the necessity of working together toward the construction of suitable models and for the solution of such complex problems. Both the need and the desirability of co-operative effort are evidenced by the current support of training in mathematical biology and by the many conferences on biology and mathematics that have been held during the past few years. This paper will discuss several multivariate methods that may be used in the analysis of dental data, illustrating the methodology with some data from families and from a dental growth study, and will outline some additional problems in dental research to which such statistical methods may be applicable.The observations of Wylie7 and Stein, Kelley, and Wood' suggest that, with respect to several cranio-facial dimensions, daughters and fathers are more alike than are daughters and mothers, and, conversely, sons appear to be more similar to their mothers. It is impossible to derive from these observations a hypothesis consistent with the theorems of

Metric dental diversity of Ryukyu Islanders: a comparative study among Ryukyu and other Asian populations

“…In order to apply this model to morphological data, i.e. to accurately meet the expectations of random breeding, an estimate of heritability is required because some researchers reported that environmental factors also influence dental dimensions (Hanna et al, 1963;Garn et al, 1979). Many dental anthropologists have reported the heritability of dental dimensions (Garn et al, 1968;Goose, 1971;Alvesalo and Tigerstedt, 1974;Potter et al, 1976;Mizoguchi, 1977;Townsend and Brown, 1978; summarized by Hillson, 1996;Scott and Turner, 1997).…”

Yugoslav Mesolithic dental reduction

“…Goose attributes the positive increase in tooth size to diet. Hanna et al (1963) noted a secular trend in tooth size of U.S. whites and blacks. Mesiodistal diameters of incisors were larger in sons than in fathers and were larger in daughters than in mothers.…”

Generational Differences in Size and Morphology of Tooth Crowns in the Young Modern Japanese.

“…He estimated that this may have been due to improvement of nutritional uptake by humans in the developmental stage (Inoue et al, 1986). Hanna et al (1963), Goose et al (1967) and Uemura et al (1983), who evaluated generational difference of tooth size, reported that tooth size might be influenced by eating behavior in all cases.…”