Radiographic assessment of maxillary sinus lateral wall thickness in edentulous posterior maxilla

Given the importance of evaluating the maxillary sinus lateral wall thickness (LWT) to avoid complications during surgery, the aim of this study was to examine LWT as well as the effect of residual ridge height (RH), edentulous region, type of edentulism, age and gender on it.

In this cross-sectional study conducted in 2016, 150 samples of the CBCT imaging archives of the Oral and Maxillofacial Radiology Clinic in Babol, Iran, were evaluated retrospectively. In the coronal section, RH and LWT (at 3, 7, 10 and 15 mm from the lowest point of the sinus floor) were measured in NNT software in millimeters. Data were analyzed using the SPSS v22 software through independent-samples t-test, paired-samples t-test and ANOVA.

In 150 assessed images, by increasing the wall distance from the floor, the mean sinus lateral wall thickness was increased (p=0.01). There was no relationship between gender and age with the sinus lateral wall thickness (p>0.05). RH showed a significant relationship with LWT so that the higher the RH, the greater the LWT (p<0.05). It was also observed that the mean LWT was 1.31±0.3 mm in the partial edentulism and 0.95±0.26 mm in the complete edentulism (p<0.05). The maximum thickness was found in the first molar and the minimum values were in the second premolar and the second molar.

Due to the impact of residual ridge height and type of edentulism on LWT and anatomical variations observed in the maxillary sinus, CBCT assessment is recommended before surgery such as sinus lifting in this area.