Correlation between third molar mineralization and chronological age by three methods

[摘要] Introduction:dental mineralization stages have been used in several studies to estimate age,and the results obtained have been found to be reliable.Objective:correlate third molar mineralization and chronological age using the methodsdeveloped by Nolla, Demirjian, and Nicodemo, Moraes and Medici Filho in a populationsample from Northeast Brazil.Methods:of a total 1 205 digital panoramic radiographs, 297 were selected of patientsroutinely seen in a private dental radiology service. All the images underwentdarkroom evaluation by three qualified examiners using the methods developedby Nolla (1960), Demirjian (1973), and Nicodemo, Moraes and Medici Filho (1974).Numerical data were summarized by location and dispersion descriptive statistics.For statistical analysis a simple linear regression model was adjusted whichconsidered age as response variable. A significance level of 5 % was adoptedfor the tests.Results:third molar development occurred earlier in males in most stages by the threemethods. In upper teeth, sexual dimorphism was more evident in Nolla stage "7"(difference of 16.34 m in tooth 18 and 14.43 m in tooth 28). In lower teeth,the greatest differences occurred in Nolla stage "6" (difference of 13.92 min 38 and 10.46 m in 48) and Nicodemo stage "5" (difference of 16.23 m higherin tooth 38 and 9.9 m in 48). Third molar development was similar on the rightand left sides, but greater in upper teeth than in lower teeth. The study alloweddevelopment of linear regression formulas based on the three methods proposed,making it possible to estimate the chronological age of the individuals in thesample.Conclusions:the three methods found a correlation between third molar development and chronologicalage.

[学科分类] 基础医学

[关键词] age determination by dental examination;panoramic radiography;third molar.