Introduction: Subjects with maxillary sinus (MS) aplasia show reduced malar prominence suggesting that MS growth may play a role in determining maxillary size. The aim of this retrospective study was to compare the MS volume (MSV), maxillary size/sagittal position, and the association between the two in subjects with bilateral impacted teeth and no impacted teeth. Materials and Methods: The study consisted of two groups, an impaction group (n=38) and non-impaction group (n=38). The MSV was calculated from CBCTs using Dolphin Software. The maxillary size and position were calculated from orthogonal Lateral Cephalograms. We performed Wilcoxon rank sum or signed rank test to analyze maxillary sinus volume and maxilla size and sagittal position between groups, and Pearson’s correlation to analyze associations between MSV and maxilla size and sagittal position. Results: Though not statistically significant, the MSV showed a trend of smaller volume in the impacted group compared to non-impacted group. The length of the maxillae and length of the midface showed a trend at being larger in the non-impaction group. Also, there was a statistically significant association between MSV and maxilla size in the non-impacted group. Conclusions: Based on the study results we speculate that MS could play a role in determining maxillary size, however the study must be repeated with larger sample size.