Tabriz University of Medical Sciences Journal of Dental Research, Dental Clinics, Dental Prospects 2008-210X 13 3 2019 11 07 The frequencies of different types of nasal septum deviation and their effect on increasing the thickness of maxillary sinus mucosa 208 214 10.15171/joddd.2019.032 EN Hamid Taghiloo Zohreh Halimi Journal Article 10.15171/joddd.2019.032 2019 04 20 2019 09 19 Background. Diseases of the paranasal sinuses are very prevalent in East Azerbaijan Province, Iran, which is attributed to various reasons, including environmental and anatomical factors. This study investigated the prevalence of anatomical variations of nasal septum deviation and evaluated the effect of this factor on increasing the mucosal thickness of the sinuses. Methods. The samples included all the patients referred to Tabriz Faculty of Dentistry, and the frequency of nasal septum deviation in the sample population was evaluated. The samples were re-examined to select the samples with a thickened mucosa of the maxillary sinus. The results were reported using descriptive statistical methods. Results. Deviation of the nasal septum was seen in 75% of the cases. The results showed that 31.76 % of males and 56.67% of females had an increased maxillary sinus mucosa thickness. Conclusion. There was a significant relationship between nasal septum deviation and thickening of the maxillary sinus mucosa.