This systematic review and meta-analysis investigates the anatomical variations in the maxillary sinus (MS) and their clinical implications. The study searched multiple databases and included 26 articles with a total of 12,969 samples, predominantly from living patients and cadavers. The most common variants reported were Haller cells, Concha Bullosa, and the number of septa, with prevalence rates of 0.30, 0.36, and 0.39, respectively. These variations can lead to sinusitis, tumors, and complications affecting neighboring structures. The review found that many variants are asymptomatic but can increase the risk of clinical complications, such as antrochoanal polyps, orbital changes, nasal septum deviation, and accessory ostia. The study highlights the importance of understanding these variations for better clinical decision-making and treatment planning. However, the high prevalence of variants suggests the need for further multicenter studies to better understand their impact on health. The review also discusses the limitations, including publication bias and potential selection bias, and emphasizes the need for ongoing research to improve knowledge and interventions related to MS variations.This systematic review and meta-analysis investigates the anatomical variations in the maxillary sinus (MS) and their clinical implications. The study searched multiple databases and included 26 articles with a total of 12,969 samples, predominantly from living patients and cadavers. The most common variants reported were Haller cells, Concha Bullosa, and the number of septa, with prevalence rates of 0.30, 0.36, and 0.39, respectively. These variations can lead to sinusitis, tumors, and complications affecting neighboring structures. The review found that many variants are asymptomatic but can increase the risk of clinical complications, such as antrochoanal polyps, orbital changes, nasal septum deviation, and accessory ostia. The study highlights the importance of understanding these variations for better clinical decision-making and treatment planning. However, the high prevalence of variants suggests the need for further multicenter studies to better understand their impact on health. The review also discusses the limitations, including publication bias and potential selection bias, and emphasizes the need for ongoing research to improve knowledge and interventions related to MS variations.