Dental Age: Effects of Estimating Different Events During Mineralization

Abstract

The extent of tooth mineralization affords apractical method for assessing an individual’s biologicalage. Dental age is useful for evaluating a child’sgrowth status, and for assessing the ages of subjects inanthropological, forensic, and medicolegal settings.Historically, some data have been collected from serialstudies (e.g., Stuart’s Harvard Study, and the BurlingtonStudy) while most studies are cross-sectional, where eachchild is examined just once. Serial and cross-sectionalstudies traditionally have been used to estimate differentsorts of information, namely the onset at a stage and theaverage age in a stage, respectively. This paper discussesthe differences of the analyses, and then presents anempirical comparison of two large sets of data on thelower third molar in American whites, showing how theconventional uses of serial data—that estimate the onsetof an event—precede the age of occurrence derived fromcross-sectional data (age at stage). Inter-group differencesfor tooth stages can exceed one year, so it is important torecognize the nature of the ‘standards’ available in theliterature.