Upper incisor intrusion: an anatomical analysis via CBCT

Area of Science:

• Dentistry
• Orthodontics
• Radiology

Background:

• Understanding the limits of tooth movement is crucial in orthodontics.
• Maxillary incisor intrusion is a complex orthodontic procedure.
• Cone beam computed tomography (CBCT) offers detailed 3D imaging of dental structures.

Purpose of the Study:

• To determine the measurable distance for bodily intrusion of maxillary incisors using CBCT.
• To investigate correlations between this distance and patient age, sex, and facial biotype.

Main Methods:

• CBCT scans of 220 maxillary incisors from 79 patients were analyzed.
• Measurements were taken from the root apex to the upper internal cortical bone along the long axis.
• Patients were categorized by age, sex, and facial divergence (hyperdivergent, hypodivergent).

Main Results:

• Mean distances exceeded 5mm for all maxillary incisors.
• Significant age-related differences were found for right lateral, left central, and left lateral incisors.
• Hyperdivergent patients exhibited greater intrusion distance in the right lateral incisor compared to hypodivergent patients.

Conclusions:

• CBCT effectively quantifies alveolar anatomy and potential for maxillary incisor intrusion.
• Older individuals demonstrated significantly greater potential for intrusion in specific incisors (12, 21, 22).
• A direct proportional relationship was observed between measurements within individual patients.