Anatomical characteristics of nasopalatine canal using cone beam computed tomography images

It is widely accepted that any interventional treatment, such as surgery, requires a precise and predetermined treatment plan. Moreover, conventional images do not allow for the presentation of all canal dimensions, and patients concepts of beauty and their expectations are greater for the premaxilla region. Therefore, the use of three-dimensional images is essential in surgical procedures, such as pathological lesions or implant placement surgeries. In cone-beam computed-tomography images, the nasopalatine canal was examined in sagittal, coronal, and axial planes. The diameters of nasopalatine and incisive foramina were separately measured, and the length of the nasopalatine canal was found by measuring the distance between the mid-levels of the nasopalatine foramen and incisive foramen. The shape of the canal was assessed in the sagittal and coronal planes in the mid-level of the canal. In addition, the shape of the canal and posterior borders were examined in the mid-level of the canal in the axial plane. The nasopalatine angle was measured as an anterior angle between the long axis of the canal and the hard palate. The number of canals in the midline and openings in each plane was also counted. The nasopalatine canal in the sagittal plane was classified into six groups: conical (33.2%), cylindrical (25.6%), hourglass (24.7%), funnel-shaped (9.8%), reverse-cone (4.3%), and spindle (2.4%). In the coronal plane, the shape of the canal was assigned to three categories: single channel (59.2%), Y-shaped (31.2%), and dual-channel (9.6%), and the posterior border of the nasopalatine canal was classified into four groups: U-shaped (42.5%), V-shaped (37.2%), reverse-V-shaped (154%), and Y-shaped (4.9%). Finally, in the axial plane, the canal shape was classified into four groups: round (40.5%), oval (31.1%), heart-shaped (21.3%), and triangle-shaped (7%). The use of three-dimensional images should be strongly considered in all surgical interventions involving the nasopalatine canal, such as dental implant placement since any error in surgical interventions will bring about serious consequences due to higher aesthetic expectations for the anterior maxillary region. Due to the lack of correct diagnosis of canal morphology in conventional images, such as periapical and panoramic radiography, it seems necessary to use three-dimensional radiography when performing surgical interventions in this region.