Prevalence and morphometriccharacteristics of fossa navicularis magna on cone beam computed tomography: a retrospective archive study

European Congress of DentoMaxillofacial Radiology, Iasi, Romanya, 25 - 27 Haziran 2026, ss.101, (Özet Bildiri)

Aim: To determine the prevalence of fossa navicularis magna (FNM) on CBCT and evaluate

whether FNM dimensions (length, depth, width) are associated with age and sex.

Materials and Methods: In this retrospective study, CBCT scans from November 2024 to

December 2025 were reviewed. Scans were acquired using a NewTom 5G unit (110 kVp, 1–20

mA; 18-s scan time; 3.6-s exposure). Adults (≥18 years) with clivus coverage and diagnostic

image quality were included; cases with motion/metal artifacts, cranial-base

trauma/surgery/major pathology, or insufficient coverage were excluded. FNM presence was

assessed; in FNM-positive cases, length and depth were measured on sagittal sections and width

on axial sections using 3D Slicer. Sex comparisons used t-test/Welch or Mann–Whitney U; age

associations were tested with correlation and regression (p<0.05).

Results: FNM was detected in 87/600 scans (14.5%; 95% CI: 11.9–17.5). Among FNM-positive

cases (n=87), age was 30.9±14.6 years; 53 were female and 34 male. Mean dimensions were

9.08±3.98 mm (length), 2.66±1.02 mm (depth), and 5.41±1.77 mm (width). Length was higher

in males than females (10.31 vs 8.29 mm; p=0.032), whereas depth and width did not differ by

sex (p>0.05). No significant associations were found between age and any measurement

(p>0.05).

Conclusion: FNM is a common incidental CBCT finding. Dimensions were not age-dependent,

while length showed a modest sex-related difference.