[Logic and myth of tooth morphology]

Area of Science:

• Dental Morphology
• Biometrics
• 3D Imaging

Background:

• Kubein-Meesenburg's theory proposes identical protrusive curvatures in individuals.
• This theory suggests an individual-specific parameter 'a' for describing these curvatures.

Purpose of the Study:

• To verify Kubein-Meesenburg's theory regarding dental cast curvatures.
• To determine if protrusive curvatures are identical within an individual.
• To assess the existence of an individual-specific parameter 'a'.

Main Methods:

• Laser scanning of 32 maxillary dental casts to obtain 3D coordinates.
• Simulation of vertical-sagittal cuts to extract protrusive curvature data.
• Application of two approximation methods: optical/graphic and strict mathematical analysis.

Main Results:

• Discrepancies were observed between the results of the two approximation methods.
• The handling of the 'third dimension' in mathematical analysis influenced the results.
• Mathematical analysis did not support the identity of protrusive curvatures within an individual.

Conclusions:

• The study refutes the identity of protrusive curvatures within any single individual.
• The existence of the proposed individual-specific parameter 'a' is denied.
• Mathematical analysis of 3D dental cast data is crucial for accurate curvature assessment.