The nasopalatine canal, a limiting factor for temporary anchorage devices: a cone beam computed tomography data study

Area of Science:

• Orthodontics and Maxillofacial Surgery
• Dental Implantology
• Radiology

Background:

• Limited knowledge exists regarding the nasopalatine canal's topography and its impact on mid-palatal temporary anchorage device (TAD) placement.
• Understanding the nasopalatine canal's relationship with adjacent bone is crucial for safe and effective TAD insertion.

Purpose of the Study:

• To evaluate the nasopalatine canal's course and adjacent vertical bone dimensions.
• To determine if these factors differ based on vertical facial types.
• To assess the nasopalatine canal's topographical predispositions as a limiting factor for mid-palatal TAD insertion.

Main Methods:

• Retrospective analysis of 398 cone beam computed tomography (CBCT) scans from patients with complete upper and lower jaw data.
• Linear measurements of the nasopalatine canal and adjacent bone at specific palatal levels (1st molar/2nd premolar, 2nd premolar/1st premolar, 1st premolar/canine).
• Assessment of maxillary and mandibular divergence using lateral cephalograms.

Main Results:

• Mean vertical bone measurements were 4.09 mm (5/6), 5.22 mm (4/5), and 3.14 mm (3/4).
• A significant negative correlation was found between jaw divergence and nasopalatine canal angulation relative to the maxillary base.
• Canal angulation was also negatively correlated with vertical bone at the 4/5 and 3/4 levels.

Conclusions:

• The 4/5 level offers sufficient vertical bone for TAD placement with minimal neuro-sensory impairment risk.
• CBCT imaging is rarely necessary for palatal implant placement.
• The nasopalatine canal's course correlates with facial patterns, suggesting distal or paramedian TAD placement in hypodivergent patients.