Affiliation:
1. Department of Pediatric Dentistry, Virginia Commonwealth University School of Dentistry, Richmond, VA 23298, USA
Abstract
Background: The concept of comparing “chronological age” vs. that of “dental age” has been well documented. Considering ethnic variations in dental development, the use of population-specific standards for age estimation has been emphasized. Mandibular maturity markers have been successfully employed to estimate the age of a person at the 18-year threshold. No such data are available for the Chinese population, which represents around one-fifth of the global human population. Aim: The aim of this research project was to analyze and grade mandibular third molars using maturity markers in the Chinese population. Materials and Methods: In total, 882 panoramic radiographs (424 females and 458 males) of 16- to 24-year-old Chinese children and young adults were obtained from patient archives. All patients were graded by a trained and calibrated examiner using stages A-D for mandibular maturity markers including Periodontal Ligament Visibility (PLV) and Root Pulp Volume (RPV). Results: The average Age at Assessment (AaA) ranged from 18.79 years for females in Stage A of PLV to 21.59 years for females in Stage D of PLV. The AaA was not statistically significant between females and males across all the stages, for both PLV and RPV. For PLV, the percentage of females below 18 years was 57.14% in Stage A and 17.14% in Stage D. For males, it was 48.84% in Stage A and 14.93% in Stage D. For RPV, the percentage of females below 18 years was 54.72% in Stage A and 12.73% in Stage D. For males, it was 49.09% in Stage A and 14.81% in Stage D. On average, for PLV, 85.30% of subjects were over 18 years of age in Stages C and D, and for RPV, 82.50% subjects were over 18 years of age in Stages C and D. Conclusions: Both RPV and PLV are considered as reliable maturity markers to estimate the age of Chinese subjects in the 18-year threshold. No difference was observed in the average Age at Assessment of mandibular maturity stages between the sexes.