Assessment of prevalence and pattern of maxillary sinus septa based on three CBCT planes: New classification in the coronal plane

Introduction

Due to the presence of the maxillary sinus and its anatomic structures, such as septa, placing dental implants in the posterior maxilla can be challenging. This study aims to determine the occurrence, distribution, and shape of these septa in the maxillary sinus.

Method

Each patient's head was aligned and evaluated the presence of septa was in the remaining 381 CBCT images and 762 sinuses across the axial, coronal, and sagittal planes. The shape of the septa was assessed in the sagittal plane (based on Sigaroudi classification) and coronal planes. The variables were compared using chi-square and Pearson’s chi-square tests.

Results

In the study of 762 sinuses, we found 194 septa in 22.17 % of the sinuses. Most of the septa were located in the posterior third of the maxillary sinus. Based on the modified Al-Faraje classification, Types I and III were the most common septa found in the study. The shapes of the septa in the coronal plane were classified into 13 groups: short vertical septa, long vertical septa, horizontal line, curved line septa, oblique septa M, oblique septa MF, oblique septa LF, oblique septa ML, hazy shape, button-like, plate-like, semicircular and atypical. There was a significant correlation between the prevalence of septa and dental status, unlike age and sex.

Conclusion

Septa occurrence can have different classifications and radiological features. Clinicians should be aware of anatomical variations in Underwood septa and consider the shapes, patterns, and involved walls of the maxillary sinus to minimize potential complications.