Purpose: The purpose of this study is to investigate the prevalence of intraosseous vascular canals in the lateral wall of the maxillary sinus by utilizing high quality Cone Beam Computerized tomography (CBCT) scans. Material and Methods: 111 CBCTs that were obtained in a private practice were randomly selected from 500 CBCTs. The CBCTs were obtained from 2007 to 2011 with an iCAT CBCT unit. Then were reconstructed and imported into Simplant pro 15 software. Among the 111 selected CBCT images 13 scans that were not covering the sinus cavity entirely or had poor quality (e.g. scattering) were excluded from the study. All the CT scans were examined for presence or absence of intraosseous anastomosis by a single investigator. All the para-axial sections were carefully observed on both left and right side. The focus was on the area that most commonly the lateral window is prepared. In other words, the main area that was evaluated was from Distal of canine to distal of second molar on each side. Result: From initial 111 selected CBCTs, 13 were excluded due to either quality or the range of coverage. 52 (53%) were female and the rest 46 (47%) were male. 54 (55.1%) anastomosis noted among the 98 CBCTs that were evaluated. In other words, in 196 sinuses that were evaluated 27.5% of them had intraosseous anastomosis. Conclusion: the presence of intraosseous vascular canals in the lateral wall of the maxillary sinus is not a prevalent finding. Learning of the presence of intraosseous anastomosis in the lateral wall of the maxillary sinus would help with minimizing bleeding complications associated with the lateral wall approach sinus augmentation technique. Therefore, evaluation of the CBCT for anatomical variations is recommended prior to sinus augmentation surgeries. / Oral Biology