title: Dental and Chronological Ages as Determinants of Peak Growth Period and Its Relationship with Dental Calcification Stages.
abstract: OBJECTIVE
  To investigate the relationship between dental, chronological, and cervical vertebral maturation growth in the peak growth period, as well as to study the association between the dental calcification phases and the skeletal maturity stages during the same growth period.
  
  
  METHODS
  Subjects were selected from orthodontic pre-treatment cohorts consisting of 420 subjects where 255 were identified and enrolled into the study, comprising 145 girls and 110 boys. The lateral cephalometric and panoramic radiographs were examined from the archives of the Department of Orthodontics, Aristotle University of Thessaloniki, Greece. Dental age was assessed according to the method of Demirjian, and skeletal maturation according to the Cervical Vertebral Maturation Method. Statistical elaboration included Spearman Brown formula, descriptive statistics, Pearson's correlation coefficient and regression analysis, paired samples t-test, and Spearman's rho correlation coefficient.
  
  
  RESULTS
  Chronological and dental age showed a high correlation for both gender(r =0.741 for boys, r = 0.770 for girls, p<0.001). The strongest correlation was for the CVM Stage IV for both males (r=0.554) and females (r=0.68). The lowest correlation was for the CVM Stage III in males (r=0.433, p<0.001) and for the CVM Stage II in females (r=0.393, p>0.001). The t-test revealed statistically significant differences between these variables (p<0.001) during the peak period. A statistically significant correlation (p<0.001) between tooth calcification and CVM stages was determined. The second molars showed the highest correlation with CVM stages (CVMS) (r= 0.65 for boys, r = 0.72 for girls).
  
  
  CONCLUSIONS
  Dental age was more advanced than chronological for both boys and girls for all CVMS. During the peak period these differences were more pronounced. Moreover, all correlations between skeletal and dental stages were statistically significant. The second molars showed the highest correlation whereas the canines showed the lowest correlation for both gender.
authors.affiliation: Post-doc Orthodontist, Department of Orthodontics, Aristotle University, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Litsas
authors.affiliation: Department of Orthodontics, Dental School, Vita-Salute San Raffaele University; Research Area in Dentofacial Orthopedics, Orthodontics and Pediatric Dentistry, Department of Dentistry, IRCCS San Raffaele Hospital, Milan, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lucchese
keywords: Chronological age; dental age; dental calcification; skeletal maturation