Examining the socioeconomic effects on third molar maturation in a Portuguese sample of children, adolescents and young adults.

Introduction: The impact of socioeconomic status (SES) on tooth mineralization has seldom been evaluated. This is important because SES can be used as a proxy for quantifying factors in the environmental that can impact mineralization but that can be difficult to measure directly, such as nutrition.
Objective: The objective of this study was to examine the effects of SES on third molar mineralization, using a sample of children, adolescents and young adults from Porto, Portugal.
Methods: Panoramic x-rays from 1747 patients (842 males and 904 females) were used in this study. Eight hundred and fifteen individuals were patients attending a private practice and were classified as high SES (384 males and 458 females), whereas the remaining 932 subjects (458 males and 474 females) were patients attending the dental clinic at the Faculty of Dental Medicine, University of Porto and were classified as low SES. Inclusion of individuals on the each SES group was also based on parental and own occupation. The mandibular third molar was assessed for its maturation using Demirjian's stages. The median age of attainment of root stages was calculated for stages D to H, using logistic regression and compared between the high and low SES samples.
Results: Boys from the higher SES group show an earlier median age of attainment for stages D, E, and F. Girls from the higher SES group also show an earlier median age of attainment, but for stages D and E. Stages G and H did not show SES differences in both sexes.
Conclusions: Patients from the higher SES group showed a consistent advancement in maturation of the third molar, although SES differences diminish and eventually disappear in the last stages of root maturation. An accelerated effect related to overweight and obesity is suggested as the primary explanation.