Computed tomography assessment of maxillary sinus hypoplasia and associated anatomical variations: a systematic review and meta-analysis of global evidence

Objective To summarize the scientific evidence on the prevalence of maxillary sinus hypoplasia (MSH) and associated anatomical variations as assessed by computed tomography scans. Study design This PROSPERO-registered systematic review followed the recommendations of the PRISMA guidelines. Search algorithms were constructed for each of the six databases and gray literature. After screening the references (Rayyan ® ), the extracted data were meta-analyzed according to a random-effects model. The joanna briggs critical appraisal tool assessed the methodological quality of the included studies. The GRADE approach was used to estimate the certainty of the evidence. Results From a total of 2781 studies screened, 22 were considered for four meta-analysis. The prevalence of MSH in 7358 patients was 5.65% (CI95% = 4.07–7.47%) with significant heterogeneity between studies ( p < 0.001, I 2 = 89.30%). MSH was identified in 295 patients, of whom 82.38% (CI95% = 75.82–88.09%) had unilateral hypoplasia and 17.62% (CI95% = 11.91–24.18%) bilateral hypoplasia with moderate heterogeneity between studies ( p < 0.0503, I 2 = 42.87%). The prevalence of MSH in 9998 maxillary sinuses was 3.77% (95% CI = 2.44–5.38%), with significant heterogeneity between studies ( p < 0.001, I 2 = 92.84%). Hypoplastic/aplastic uncinate process, concha bullosa and paradoxical concha were the most reported anatomical variations. The studies presented a low-moderate methodological quality. The certainty of the evidence was very low to moderate. Conclusion The prevalence of maxillary sinus hypoplasia observed was 5.65%, with most cases being unilateral.