Reliability of Different Anterior Cranial Base Reference Areas for Voxel-Based Superimposition

Area of Science:

• Dentistry
• Orthodontics
• Radiology

Background:

• Accurate 3D superimposition of serial cone-beam computed tomography (CBCT) images is crucial for assessing craniofacial growth and treatment outcomes.
• Voxel-based superimposition techniques offer advanced methods for aligning 3D datasets.

Purpose of the Study:

• To evaluate and compare the reliability and reproducibility of two 3D voxel-based superimposition techniques for craniofacial CBCT images.
• To compare the outcomes of superimposition using total anterior cranial base (TACB) versus middle anterior cranial base (MACB) as reference structures.

Main Methods:

• Fifteen pairs of serial CBCT scans were superimposed using Dolphin 3D software.
• Superimposition was performed on either the TACB or MACB structures.
• Reliability was assessed by visual overlap, and reproducibility was evaluated by repeating superimpositions and comparing T0/T1 changes.

Main Results:

• Superimposition on TACB demonstrated perfect reliability, while MACB showed moderate reliability (p = 0.044).
• Both methods exhibited good overall reproducibility, but MACB had greater individual variations (-1.84 to 1.64 mm) compared to TACB (-0.48 to 0.31 mm).
• Overall agreement in detected changes was good, but individual measurements showed significant reduction for MACB.

Conclusions:

• 3D voxel-based superimposition on the total anterior cranial base (TACB) is more reliable and reproducible than using the middle anterior cranial base (MACB).
• The extended anterior cranial base area (TACB) is recommended for precise assessment of craniofacial changes using CBCT imaging.