Radiological evaluation of maxillary sinus anatomy: A cross-sectional study of 300 patients.

Objective: The aim of the present study was to evaluate the principal anatomical characteristics of the maxillary sinus using Cone Beam Computed Tomography (CBCT) in order to facilitate prevention of intra- and post-operative complications.

Methods: Three hundred CBCT scans from patients undergoing implant surgery were analysed. The following anatomical structures were evaluated: (1) Residual ridge height (RRH) and width (RRW); (2) Ridge bone density (BD); (3) Maxillary sinus angle (MSA); (4) Maxillary sinus lateral wall thickness (LWT); (5) Schneiderian membrane thickness (MT); (6) Maxillary sinus septa (SS); (7) Posterior superior alveolar artery (PSAA).'

Results: Mean patient age was 59.5±13.6. Mean RRH at upper second premolar (2PM) was 8.66±3.95mm, 4.90±2.28mm at first molar (1M), and 5.26±2.13mm at second molar (2M). Mean RRW was 6.72±2.69mm at 2PM, 6.87±2.65mm at 1M and 7.09±2.80mm at 2M. Bone density was 330.93±211.02 Hounsfield Units (HU) at first molar position and MSA was 73.39±15.23°. LWT was 1.95±0.98mm. Mean Schneider Membrane thickness (MT) was 1.82±1.59mm; MT was ≤3mm in 72.9% of patients and >3mm in 27.10%. 20.56% of patients presented bucco-palatal oriented septa with a mean height of 13.11±3.82mm. PSAA was observed in 48.60% and mean distance to the top of the ridge was 13.15±3.71mm, and was mostly observed inside the sinus (53.85%).

Conclusions: CBCT scanning has been shown to be a useful tool for evaluating maxillary sinus anatomical variations. CBCT should be considered the gold standard when evaluating the maxillary sinus area.