PSAA and IOF are branches of the maxillary artery and they are related to maxillary bone and maxillary sinus. The prevalence of PSAA varies in the literature. Elian et al.7 and Mardinger et al. 8 reported the prevalence of PSAA as 52.9% and 55%, respectively. Güncü et al. 3 reported the prevalence of PSAA as 64.5%, while İlgüy et al.9 reported as 89.3%. The prevalence of PSAA was reported as 52.8% by Jung et al. 10 and as 90% by Kang et al. 11. In the present study, the prevalence of PSAA was found as 56.2%, consistent with the literature.
In their study they conducted by using CBCT, Kim et al.12 reported the prevalence of PSAA as 64% in men and as 40% in women and they reported a significant correlation between gender and the prevalence of PSAA. On the contrary, no statistically significant correlation was found between the prevalence of PSAA and the gender of the participants (p = 0,603).
As the diameter of PSAA, which supplies the sinus membrane and the lateral wall of the maxillary sinus, increases, the risk of bleeding increases in surgical operations. Mardinger et al.8 reported that arteries which had a diameter larger than 1 mm could be a risk in terms of bleeding during surgical procedures. Mean diameter of PSAA was reported as 1.2 mm by Ella et al.4, as 1.3 mm by Güncü et al.3, as 1.52 mm by Kim et al.12 and as 0.94 mm by İlgüy et al.9. The present study evaluated both the horizontal diameter and the vertical diameter of PSAA. Mean value for vertical diameter was found as 1,67 ± 0,74 mm, while mean value for horizontal diameter was found as 1.14 ± 0.4 mm. While the rate of those with a vertical diameter of ≥ 1mm was 92.1%, the rate of those with a horizontal diameter of ≥ 1mm was 65.4%. In order to prevent a possible complication that can occur in the presence of large arteries over 1 mm in diameter, the diameter of PSAA on radiographic images should be examined carefully before surgical procedures.8
In their studies, Keçeli et al.13 and Mardinger et al.8 reported that PSAA diameter was not significantly different between genders. On the other hand, Khojastehpour et al.14 found the mean diameter of PSAA as 1.33 ± 0.69 mm and 1.04 ± 0.76 mm, respectively in men and women. İlgüy et al.9 reported that the rate of 1–2 mm PSAA was statistically significantly higher in men (39.8%) when compared with women (25.2%); Güncü et al.3 found that mean diameter of PSAA, which was 1.4 ± 0.4 mm and 1.1 ± 0.3 mm, respectively in men and women, was statistically significantly different between genders.
In our study, statistically significant difference was found between median values of vertical and horizontal diameter in terms of gender (p = 0.003, p = 0.004). While mean horizontal diameter was 1.23 ± 0.45 mm in men, it was found as 1.06 ± 0.33 mm in women. While mean vertical diameter was 1.78 ± 0.65 mm in men, it was 1.57 ± 0.8 mm in women. In our study, PSAA diameter was found to be larger in men when compared with women.
When we examined the localisation of PSAA in the maxillary sinus, in Güncü et al.3’s study, it was intraosseously located in 68.2%, intrasinusally located in 26% and extrasinusally located in 5.7%. İlgüy et al.9 reported that PSAA was intraosseously located in 71.1%, intrasinusally located in 13% and extrasinusally located in 5.2%. The results of our study were found to be in parallel with the literature and it was found that PSAA was intraosseously located in 60.2%, intrasinusally located in 28.3% and extrasinusally located in 11.5%.
In the present study, when the localization of PSAA was examined according to teeth, the highest rate of PSAA was found in the distal of second molar with a rate of 34.6%. The least common localizations were the alignment of first molar and the distal of first molar with 3.1%. Statistically significant correlation was found between the localization of the participants in terms of age categories (p = 0.030). Unlike the other age groups, PSAA was most commonly seen at the second molar level in the 48–62 age category. Statistically significant correlation was found between the localization of the participants in terms of gender (p = 0.042). Here the difference was between the second molar and the distal of third molar. While the rate of those at the second molar level was 14.1% in men, this rate was 23.2% in women. While the rate of those at the distal of the third molar was 8.7% in men, this rate was found as 1% in women. There are no studies in literature with which we can compare these data.
In the study of Solar et al.15, the vertical distance from the lower border of PSAA to the alveolar crest was measured as 18.9 mm. In Elian et al.7’s study, this distance was found as 16.4 mm, while it was found as 16.9 mm in Mardinger et al.8’s study. In the anatomical study by Rosano et al.2, the distance between alveolar crest and PSAA was measured as 11.25 mm. In Kim et al.12’s study, it was measured as 18.90 mm in the second premolar region and as 15.45 mm in the second molar region, and it was found that age and gender did not affect this distance. In our study, the distance of PSAA to the alveolar crest was found to be higher than the values in the literature and the mean value was found as 21.99 ± 4.59 mm. This may be due to the fact that the patients in the present study were selected among individuals who did not have missing posterior teeth. It was also found in our study that the median values of the distance from PSAA to the crest was statistically higher in men.
There are different results in literature on the vertical distance between PSAA and the base of maxillary sinus. In our study, the mean value of distance to the base of the maxillary sinus was found as 9.32 ± 3.86 mm. This distance was measured as 7.8 mm in Güncü et al.3’s study. In the present study, in parallel with the studies of Güncü et al.3 and İlgüy et al.9, the median values of the distance from PSAA to the base of maxillary sinus was statistically significantly higher in men.
The mean distance between PSAA and the medial wall of maxillary sinus was found to be in parallel with the literature and it was found as 12.48 ± 4.26 mm. In their studies, Kim et al.12 and Güncü et al.3 reported the distance of PSAA to the medial wall of maxillary sinus as 11 mm. In İlgüy et al.9’s study, the distance to the wall of maxillary sinus was found to be higher in men when compared with women and in dentate patients (13.92 mm) when compared with edentulous patients. No statistically significant difference was found in our study between the values of distance to the wall of the medial sinus between genders and age groups.
In our study, the mean distance of PSAA to the midline was found as 28.13 ± 4.88 mm. Statistically significant difference was found between the median values of distance to the midline in terms of gender. No studies were found in literature which evaluated the distance of PSAA to the midline.
IOF is an important anatomical structure through which the infraorbital artery and nerve pass. It was seen with a rate of 100% in the present study and in all studies conducted. Our study examined both horizontal and vertical diameters of IOF and while the mean horizontal diameter was found as 3.47 ± 0.81 mm, the mean vertical diameter was found as 3.68 ± 0.83 mm. In a study conducted by Ilayperuma et al.16 on 108 skulls, mean vertical diameter of IOF was found as 3.05 ± 0.88 mm in women and as 3.75 ± 0.79 mm in men and this value was found to be higher in men.
Dağıstan et al.17 evaluated the vertical diameter of IOF in terms of gender and they reported that there were no statistically significant differences, while the vertical diameter of IOF was higher in men. In a study Sinanoğlu et al.18 conducted on 182 CBCT images and in a study Dağıstan et al.17 conducted on CBCT coronal plane sections of 125 cases, IOF horizontal diameter value was found to be statistically higher in men. In our study, in parallel with the literature, the median vertical and horizontal diameter values were found to be statistically significantly higher in men (p < 0.001). This difference may be due to the differences in the size of skull between genders.19
Statistically significant difference was found between IOF horizontal diameter median values in terms of age categories (p = 0.002). The values in 18–27 age category and 48–62 age category were found to be different. It can be concluded that IOF horizontal diameter values increase as age increases.
The appearance of IOF has been classified different in different studies. Ilayperuma et al.16 found that 57.4% of IOFs were oval, 31.4% were semi-circular and 11.1% were circular. In a study Orhan et al.20 examined the shape of IOF in CBCT 3D reconstruction images, they found that 26% of 354 IOFs were circular, while 74% were oval. Unlike other studies, in our study, while CBCT was used as coronal section, the most common shape was semi-circle with a rate of 49.4%.
Especially for surgeons of the head and neck region, it is very important to know the localization of IOF in surgical procedures such as reconstructive and ortognatic surgery.21,22, 23 Localizations of IOF relative to maxillary teeth have been examined with skull and cadaver studies in different societies in literature. In a study İbrahim et al.24 conducted on 200 patients by using CBCT, they reported 46% of IOFs to be located on the right, 44.5% to be located on the left and mostly at the second premolar level. In a study they conducted on 108 skulls (38 females and 70 males) Ilayperuma et al.16 found that IOF was on the same vertical plane with the second premolar with a rate of 55.56%, between the first and second premolar with a rate of 29.63%, between the second premolar and first molar with a rate of 11.1% and the first molar with a rate of 3.7%. In our study, in parallel with the literature, IOF was seen mostly at the second premolar level. Similar to İbrahim et al.24’s study, coronal, sagittal and axial sections were used to determine localization.
Another parameter examined in our study is the distance of IOF to the midline. In their studies, Ilayperuma et al.16, İsmail et al.25 and Bahşi et al.26 reported that the distance of IOF to the midline was statistically higher in men. In this study, the distance of IOF to the midline was found to be higher in men (p < 0.001). Dağıstan et al.17 found that there were no statistically significant differences in the distance of IOF to the midline on CBCT coronal plane sections in terms of gender, age groups and the sides.
In our study, statistically significant difference was found between the median values of distance to the midline in terms of age categories (p = 0.002). It can be concluded from this result that the distance of IOF to the midline increases as age increases.