Estimating age using permanent molars and third cervical vertebrae shape with a novel semi-automated method

Area of Science:

• Forensic Anthropology
• Radiology
• Dental Age Estimation

Background:

• Accurate chronological age estimation in young adults is difficult.
• Existing methods for age assessment require enhancement for improved accuracy.
• Distinguishing individuals below 18 from those 18 and above is crucial in legal and forensic contexts.

Purpose of the Study:

• To explore a novel semi-automated method for assessing age-related shape changes in the third cervical vertebra (C3) in living individuals.
• To compare the efficacy of C3 shape analysis with tooth formation assessment of the second and third mandibular molars (M2 and M3) for age categorization.
• To determine if individuals can be reliably categorized as less than 18 years (<18) or at least 18 years (≥18) of age using these methods.

Main Methods:

• Utilized panoramic and lateral skull radiographs from 174 dental patients (aged 15-22 years; 78 males, 96 females).
• Assessed twelve variables of the third cervical vertebra (C3) and tooth formation stages of M2 and M3.
• Compared variables between two age groups (<18 and ≥18 years) separately for males and females using t-tests.

Main Results:

• Significant age-related differences in C3 shape were observed: eight variables in males and one in females (p < 0.05).
• For males, the C3 height-to-width ratio was the best indicator for age ≥18; for females, diagonal ratios were most effective.
• M2 showed advanced formation in 69% of males and 83% of females. M3 exhibited high variability, was missing in 24-28% of individuals, and mature in only 14-15%.

Conclusions:

• Third cervical vertebra (C3) shape changes demonstrate potential as an additional method for age estimation in young adults.
• C3 analysis offers a promising approach to categorize individuals into <18 and ≥18 age groups.
• Mandibular molar (M2, M3) development, particularly M3, showed less reliability for precise age categorization in this age range.