Mineralization of the mandibular third molar

A study of American Black and Whites

Research output: Contribution to journalArticle

57 Citations (Scopus)

Abstract

The tempo of tooth mineralization is under significant genetic control, and the orderly progression of morphological changes-in concert with the long span during growth in which teeth form-makes "dental age" a useful measure of a person's degree of biological maturity. The third molar is of particular interest because (1) it is the last and most variable tooth to form and (2) it is the only tooth to complete formation after puberty, which has made it attractive in forensic and legal circles as an estimator of adulthood. Age standards are described here for mandibular third molar formation stages in a cross-sectional sample of 4,010 persons (age range: 3-25 years), with proportionate sample sizes of American blacks and whites and males and females. Formation was scored against the 15-grade ordinal scheme of Moorrees, and descriptive statistics were computed using proportional hazards survival analysis. Blacks achieved each formation stage significantly ahead of whites, but not in a uniform manner. Instead, there was an enhanced advancement in blacks during crown formation and during late stages of root formation. In both races formation proceeded faster in males, which is unique for the third molar, as prior studies suggest. Sample variance increases with the stage of formation, such that 95% confidence limits span 8 or more years for root formation stages. Consequently, the third molar provides a rough gauge of an individual's chronological age, but the considerable variability precludes any precise estimate, particularly in late adolescence where most forensic interest has focused.

Original languageEnglish (US)
Pages (from-to)98-109
Number of pages12
JournalAmerican Journal of Physical Anthropology
Volume132
Issue number1
DOIs
StatePublished - Jan 1 2007

Fingerprint

Third Molar
Tooth
puberty
human being
descriptive statistics
maturity
adulthood
adolescence
Puberty
Survival Analysis
Crowns
confidence
Sample Size
hydroquinone
Growth

All Science Journal Classification (ASJC) codes

  • Anatomy
  • Anthropology

Cite this

Mineralization of the mandibular third molar : A study of American Black and Whites. / Harris, Edward.

In: American Journal of Physical Anthropology, Vol. 132, No. 1, 01.01.2007, p. 98-109.

Research output: Contribution to journalArticle

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