Predictors of variation in mandibular incisor enamel thickness

Area of Science:

• Dental Anatomy
• Orthodontics
• Anthropology

Background:

• Interproximal reduction of mandibular incisor enamel is a common orthodontic procedure.
• Understanding variations in enamel thickness is crucial for safe and effective treatment.

Purpose of the Study:

• To identify factors influencing variations in mandibular incisor enamel thickness.
• To compare enamel thickness across different incisor types, surfaces, sexes, and ethnicities.

Main Methods:

• Comparative analysis of enamel thickness in mandibular central and lateral incisors.
• Evaluation of mesial versus distal surface thickness.
• Comparison between male and female subjects, and between African-American and white subjects.
• Correlation analysis between tooth width and enamel thickness.

Main Results:

• Lateral incisors, distal surfaces, and Black subjects exhibited significantly greater enamel thickness (P<.0001).
• No significant differences in enamel thickness were found between male and female subjects.
• Wider teeth were associated with greater enamel thickness (P<.01), with substantial individual variation (0.44-1.28 mm).

Conclusions:

• Enamel thickness is greater on the distal aspect of lateral incisors, in Black individuals, and in wider teeth.
• Identified factors do not fully account for the observed variations in enamel thickness.
• Clinicians should use calibrated radiographs to measure enamel thickness due to extensive individual variability before enamel reduction.