Micro-CT study on isolated teeth with hereditary dentin defects.

Area of Science:

• Dental science
• Biomaterials science
• Radiology

Background:

• Dentinogenesis imperfecta type II (DGI-II) and dentin dysplasia type I (DD-I) are hereditary dentin defects affecting tooth structure and mineralization.
• Understanding the three-dimensional (3D) internal structures and mineralization densities of these teeth is crucial for diagnosis and management.

Purpose of the Study:

• To construct 3D structures of teeth from patients with DGI-II and DD-I using Micro-CT.
• To analyze the internal morphology and hard tissue mineralization density of affected teeth.

Main Methods:

• Reconstruction of 3D tooth structures from third molars of DGI-II, DD-I patients, and healthy controls using Micro-CT.
• Observation of internal structures along sagittal and transverse planes.
• Calculation of grayscale values in enamel, crown dentin, and root dentin to assess mineralization density.

Main Results:

• Successful 3D reconstruction of teeth with hereditary dentin defects, including enamel cap, dentin core, and pulp cavity.
• DGI-II teeth exhibited incompletely calcified pulp cavities and narrow root canals.
• DD-I teeth showed obliterated pulp cavities and root canals, with absent roots; both DGI-II and DD-I groups had lower mineralization than controls, with DD-I showing more significant root dentin mineralization reduction.

Conclusions:

• Micro-CT is an effective method for 3D reconstruction and quantitative analysis of mineralization density in teeth with hereditary dentin defects.
• Both DGI-II and DD-I teeth display reduced dentin mineralization, with DD-I being more severely affected.
• Abnormal pulp cavity calcification and narrow or occluded root canals are characteristic findings.