MAXILLARY SINUS SEPTA: PREVALENCE AND ASSOCIATION WITH GENDER AND LOCATION IN THE MAXILLA AMONG ADULTS IN SANA'A CITY, YEMEN

Yahya Abdullah Ahmed Alhadi1image, Nashwan Yahya A Al-Shamahi2image, Khaled A AL-Haddad3image, Abdulwahab Ismail Mohamed Al-Kholani4image, Mohammed Mohammed Ali Al-Najhi4,5image, 

Hassan Abdulwahab Al-Shamahy6,7image, Mohammed A Al-labani3image

1Department of Oral and Maxillo-Facial Surgery, Faculty of Dentistry, Sana’a University, Republic of Yemen. 

2Medicine Department, Faculty of Medicine and Health Sciences, Sana’a University, Republic of Yemen.

3Orthodontics, Pedodontics and Prevention Department Faculty of Dentistry, Sana'a University, Yemen.

4Department of conservative dentistry, Faculty of Dentistry, Sana’a University, Republic of Yemen.

5Orthodontics, Pedodontics and Prevention Department Faculty of Dentistry, Genius University for Sciences & Technology, Dhamar city, Republic of Yemen. 

6Departement of Basic Sciences, Faculty of Dentistry, Sana’a University, Republic of Yemen.

7Medical Microbiology department, Faculty of Medicine, Genius University for Sciences &  Technology, Dhamar city, Yemen.

ABSTRACT

Background and aims: Maxillary sinus septa are partitions of cortical bone dividing the sinus into multiple compartments. Their presence and dimension are of relevance to periodontitis, oral and maxillofacial surgeons as well as otolaryngologists. The aim of this study was to determine the prevalence and association of maxillary sinus septum with gender and location in maxilla among adults in Sana’a city, Yemen.

Methods: This is a retrospective study carried out on 633 patient orthopantomograms (OPGs) which had visible maxillary sinus without pathological or developmental changes from the first of March 2021 to the end of February 2022 at the Department of Oral and Maxillo-Facial Surgery, Faculty of Dentistry, Sana’a University and private clinics in Sana’a city. Descriptive statistics of the continuous variable (age) was summarized as mean and standard deviation while the categorical variables were summarized as frequencies and percentages and presented as tables. Bivariate analysis was performed to test for association between the dependent variables (maxillary sinus septum presence, presentation and position) and independent variables (gender and location). 

Results: The mean age of the patients was 29.59 years, range from 16 -56 years, and females 380 (60.0%). Of 259 (40.9%) maxillary sinus septum identified, 206 (79.5 %%) were from females. Majority 180 (69.5%) were unilateral, while 79 (30.5%) were bilateral. Occurrence of unilateral maxillary sinus septum was higher in males 104 (41.1%) with OR=2.8, 95% CI=1.9-3.98, p<0.0001; than females (20%), while bilateral septum occurs roughly in equal rates in both gender (11.86 VS 12.89%).  

Conclusion: This study has shown a significant proportion of maxillary sinus septum among patients with visible orthopantomogram without pathology in Sana’a, Yemen, with the highest proportion being females. There is therefore the need for the occurrence and presentation of maxillary sinus septum in this study to serve as a baseline data in the treatment of dental implant and surgical procedures in Sana’a, Yemen. 

Keywords: Maxillary sinus; prevalence; septa; variation, Yemen.

 

INTRODUCTION

 

Previously, the maxillary septum was considered a normal contrast with little clinical significance. But nowadays, the importance of the maxillary septum has become clear after the popularity of maxillary sinus augmentation procedures for dental implants. The mechanism controlling septal development is not known to be clear, although a role for irregular sinus floor pneumatization after tooth extraction has been suggested. Determining the location and structure of the sinus septum is essential for sinus surgeries and especially sinus augmentation in implant surgery1. The maxillary sinus septum is the septum of the cortical bone that divides the floor of the maxillary sinuses into multiple compartments, which are known as recesses2. The role of the septum is to separate the sinuses into two or more antras, as well as to strengthen the bone structure of the sinuses1. It is known that the presence and dimensions of the maxillary septum are of practical relevance to periodontists, oral and maxillofacial surgeons, as well as ENT specialists3. The existence of the maxillary sinus septum has been revealed to be a risk factor for sinus membrane perforation during external lifting procedures of the maxillary sinus4. Disappointingly, there is inadequate data on the prevalence and pattern of the maxillary sinus septum and its relationship to maxillary sinusitis. Regarding implant placement, septa that appear in the floor of the sinuses or along the side wall can interfere with their placement either directly by being in the area of their placement or indirectly by impeding wall height during the side sinus approach5.

Structurally, the maxillary sinus septum has been described as inverted gothic arches originating from the inferior and lateral walls of the sinuses and reaching a sharp edge along their apical edges; They can divide the sinuses into two or more parts6. Vinter et al., note that the resorption of the maxillary alveolar process takes place irregularly in different areas leaving bony apex on the floor of the sinusoids7. Krennmair et al., classifies the congenital and acquired septum into primary septum, which can develop in all regions of the maxillary sinuses, arising during maxillary development, and secondary septa, which arise from irregular pneumatization of the sinus floor following tooth loss8.  However, the exact mechanism responsible for maxillary septum development is still unclear, although a role for the irregular pneumatization of the sinus floor fol­lowing tooth loss has been suggested5.  The prevalence of mul­tiple septa in the maxillary sinus varies from 7% to 58% in the literature7.  However, possible differences between eth­nic groups may contribute to these differences9.

In Yemen, epidemiological or curative studies devoted to research in dental sciences are still limited and none of these studies dealt with the prevalence of max­illary sinus septa in sample of Yemeni population10-0, and for this reason it is necessary to strengthen, update, build and continue to bear the costs of studies on topics of interest to oral and dental surgery with a plan to achieve a better effect to the public and health, with the dissemination of appropriate knowledge with a plan to enhance the success of surgical procedures and reduce the potential subsequent consequences of the failure of these treatments. Therefore, this study will provide an insight on the prevalence of max­illary sinus septa in sample of Yemeni population.

 

MATERIALS AND METHODS 

 

This is a retrospective study car­ried out in the Department of Oral and Maxillo-Facial Surgery, Faculty of Dentistry, Sana’a University clinics after ethical approval from the institution. The study was carried out for a period of 12 months. 

Sample size calculation: The sample size of 634 was estimated assuming an expected prevalence of maxillary sinus septum of 34.18% from a previous study in Yemen31, margin of error 3.69 with a confidence level of 95% using the Epi Info 7.2 calculator (CDC, Atlanta, USA), but 633 it is the number that was collected and its data analyzed, and this difference would not affect the results of the study.

Study population: 

Inclusion criteria: This includes all the patients orthopantomograms acquired from Proline XC  modal (Planmeca Co., Helsinki, Finland) taken as part of treatment planning or oral diagnosis, that had full set of teeth with clear and visible maxillary sinuses, from the first of March 2021 to the end of February 2022. 

Data collection:  The orthopantomograms were examined by an oral and maxillofacial radiologist (to obtain more accurate results) to reveal the maxillary sinus septum. Presence or absence of maxillary sinus septum, presentation, position, and location were retrieved then register with patient age and sex data using a questionnaire that was kept until the results were analyzed.

Exclusion criteria: Orthopantomogram with poor quality, lacking sufficient contrast, distorted image and clarity with evidence of previous sinus intervention and pathological or developmental changes in the maxillary sinuses were excluded from the study (they were excluded because it is difficult to reveal the maxillary sinus septum).  

Statistical analysis: Data were analyzed with Epi Info 7.2 (CDC, Atlanta, USA). The continuous variable (age) was summarized with mean and standard deviation while the categorical variables (maxillary sinus septum presence, presentation, position, location, and patients age group and gender) were summarized with frequency and percentages and display as tables. Bivariate analysis was performed to test for association between the independent variables (gender and location) and dependent variables (maxillary sinus septum presence, presentation and position). A p-value<0.05 was considered statistically significant.

Ethical Consideration: Ethical approval for this study, No: 371 dated January 21, 2021 was obtained from the Medical Ethics and Research Committee of the Faculty of Medicine and Health Sciences, Sana’a University. All procedures were according to the ethical guidelines of the review committee. 

 

RESULTS 

 

The study included 253 (39.96%) males and 380 (60.04%) females. Most of the participants were in the age group 26-35 years (40.6%), followed by 16-25 years (37.3%) and 36-45 years (19.3%), while only 2.8% were in the age group >45 years. The mean age of the patients was 29.59 years, and range from 16-56 years.  The current rate of the maxillary septum was 40.9% (Table 1). Considered the septa presentation, the rate of bilateral septum was 52.96%, while the rate of the unilateral septum was 54.2%. Looking at septa position, the rate of right septum was 57.64%, while the rate for the left septum was 42.35%.

Considering the septa location, most of the septa location was anterior (42.94%), followed by the middle location (37.05%), while the posterior septal location was only 20% (Table 2). There was no significant association of the presence of the maxillary septum with gender with OR=0.95, 95% CI=0.69-1.3, p=0.75. There was a significant association of the presence of the maxillary septum with the anterior site with OR=3.05 95% CI=2.34 - 3.99, p<0.0001. Also, there was a significant association between the presence of the maxillary septum with the middle site with OR=2.1, 95% CI=1.6-2.7, p<0.0001.

However, there was no association between the presence of the maxillary sinus septum with posterior location with OR=0.67, 95% CI=0.5-0.9, p=0.009 (Table 3). 

Considering the aassociation of maxillary sinus septum bilateral presentation with gender and location, there was no significant association of the bilateral presence of the maxillary septum with gender with OR=0.9, 95% CI=0.55-1.4, p=0.69. While there was a significant association of the presence of the bilateral maxillary septum with the anterior location with OR=3.2, 95% CI=2.1-4.9, p<0.0001. Also, there was a significant association between the presence of the bilateral maxillary septum with the middle location with OR=2.4, 95% CI=1.5-3.6, p<0.0001. Also, there was a significant association between the presence of the bilateral maxillary septum with the posterior location with OR=4.99, 95% CI=2.96-8.4, p<0.0001 (Table 4).  

Considering the aassociation of maxillary sinus septum unilateral presentation with gender and location, there was significant association of the unilateral presence of the maxillary septum with male gender with ratio=41.1%, OR =2.8, 95% CI=1.9 – 3.98, p<0.0001. There was a significant association of the presence of the unilateral maxillary septum with the anterior location with OR=4.9, 95% CI=3.4-7.2, p<0.0001. Also, there was a significant association between the presence of the unilateral maxillary septum with the middle location with OR=4.3, 95% CI=2.8-6.5, p<0.0001. Also, there was a significant association between the presence of the unilateral maxillary septum with the posterior location with OR=2.2, 95% CI=1.3–3.6, p=0.002 (Table 5). Considering the aassociation of maxillary sinus septum right position with gender and location, there was no significant association of the right presence of the maxillary septum with gender with, OR=1.38, 95% CI=0.98-1.9, p=0.06.

There was a significant association of the presence of the right maxillary septum with the anterior location with OR=4.9, 95% CI=3.3-7.2, p<0.0001. Also, there was a significant association between the presence of the right maxillary septum with the middle location with OR=3.8, 95% CI=2.5-5.7, p<0.0001. Also, there was a significant association between the presence of the right maxillary septum with the posterior location with OR=2.8, 95% CI=1.95-3.98, p<0.0001 (Table 6). Considering the aassociation of maxillary sinus septum left position with gender and location, there was significant association of the left position of the maxillary septum with male gender with ratio= 28.1% (vs 19.1% of female), OR=1.6, 95% CI=1.1-2.3, p=0.009. There was a significant association of the presence of the left maxillary septum with the anterior location with OR=3.3, 95% CI=2.2- 5, p<0.0001. Also, there was a significant association between the right   maxillary septum with the middle location with OR=3.99, 95% CI=2.6- 6.1, p<0.0001. Also, there was a significant association between the presence of the right maxillary septum with the posterior location with OR=2.5, 95% CI=1.4-4.3, p=0.004 (Table 7).

 

DISCUSSION 

 

The present study observed the maxillary sinus septum on panoramic radiographs. This method is the most common diagnostic method used in preoperative evaluation of the paranasal sinuses, and it is affordable32. The incidence of the maxillary septum at the current study was 40.3% by subjects (Table 2); numbers roughly parallel to those reported among the Jordan population by Samara et al.,33 where the prevalence of maxillary sinus septum was 42.3% 33. Zyl et al.,34  however, they reported a higher preval-ence of maxillary sinus septum where the prevalence of maxillary sinus septa was 69%, with a large number of these patients showing multiple septa34. On the other hand, Yang et al.,35 a very low prevalence of 9% of the maxillary sinus septum was reported 35. This difference in prevalence can be justified by the dissimilar methods used in the different studies, or by differences between CT and panorama machines, as recent versions make visualization and identification of the upper septum much easier, and this is reflected as higher prevalence. 

The result of the current study showed no association between septal incidence and sex as septal prevalence was almost equal in both sexes (males=52.96% vs females=54.2%, with OR=0.95, 95% CI=0.69-1.3, p=0.75) (Table 3). These results were different from the observations reported by Shen et al.,9 Al-Zahrani et al.,36 Orhan et al.,37; the male septal rate was higher than that of female patients. Our results also differ from those reported by Park et al.,1 and Malik et al.,38 where the septum rate is higher in females than in males 1,38. The average maximum bite force in males is observed to be significantly higher than in females, which could explain the difference in septa prevalence based on sex in previous studies39. Moreover, in the current study, there was significant association of the unilateral presence of the maxillary septum with male gender with ratio=41.1%, OR =2.8, 95% CI=1.9-3.98, p<0.0001 (Table 5).  Similar observations have been reported in studies by Shen et al.,9 Al-Zahrani et al.,36, and  Orhan et al.,37. However, a greater prevalence of females has been observed by Park et al.,1 and Malec et al.,38.  

The right maxilla showed a greater spread of the septum compared to the left (64.44% vs 35.2%) (Table 2). Dandekeri et al.,5 and Kannaperuman et al.,40 studies have also shown a greater presence of the septa on the right side than on the left side5,40; While Park et al.,1 note a greater prevalence of the left-sided septum although Park et al., result’s was not statistically significant1. While Samara et al.,33 reported that the occurrence and rate of the maxillary septum in the right and left sinuses are more often than not the same, which is about 8%33; in fact this is also comparable to the results of Shen et al., where the rate of the nasal septum on the right side was comparable to the left side9.

Septa are categorized under headlines such as septa morphology, orientation and location. When septa are estimated in terms of location, anterior septa be located between the first and second premolar locality (sinus anterior wall) and the mesial of the first molar. The septa of middle region are existent between the mesial of the first molar and the mesial of the second molar. Posterior septa are between the distal of the second molar and the posterior sinus wall41. The current study showed that the largest number of septa was located in the anterior region (42.94%) followed by the middle region (37.05%) and less frequently the posterior region (20%) (Table 2). Similar prevalence of the septum in the f anterior region was revealed by Selcuk et al.,42 and Jang et al.,43 studies in which the anterior septum is reported to be more prevalent than the middle and posterior region42,43. However, our findings were different from those reported by Park et al.,1; Shen et al.,9 and Orhan et al.,37 in which septal prevalence in the middle region was the predominant feature in both CBCT (cone beam tomography) panoramic radiography.

Due to the raise in sinus floor elevation measures by general practitioners, additional complications of sinus floor elevation are observed. This is may be due to deficient in formal training or insufficient training to perform this type of surgery and ignorance of sinus anatomy. This underscores the need for studies of the max­illary sinus for the different regions of the world. Schneiderian membrane perforation has been reported to be as high as 44% as reported by Cakur et al.,44 and Schwartz-Arad et al.,45.  One of the pos­sible causes of such a high perforation rate of the Schnei­derian membrane during sinus floor elevation is the pres­ence of septum45. Presence of septa in the floor of the sinus or along the lateral wall, can interfere with the placement of an implant either directly by being present in its area of placement or indirectly by hindering the elevation of the wall during lateral sinus approach5.

Limitations 

This research suffers from specific limitations ranging from common flaws (not all results and answers to all research questions were comparative and justified) due to the lack of previous comparable studies in Yemen. There were methodological problems such as one case missing from the study, and the participants were not representative of the population of Yemen, so it is recommended that further studies in a larger sample size be conducted in different regions in Yemen using CT technology.

 

CONCLUSION 

 

This study has shown a significant proportion of maxillary sinus septum among patients with visible orthopantomogram without pathology in Sana’a, Yemen, with the highest proportion being females. The most common septum presentation was unilateral which appears typically among males. There is therefore the need for the occurrence and presentation of maxillary sinus septum in this study to serve as a baseline data in the treatment of dental implant and surgical procedures in Sana’a, Yemen. 

 

ACKNOWLEDGMENTS 

 

The authors thank the Faculty of Dentistry, Sana'a University, Sana'a, Yemen for their generous support. 

 

CONFLICT OF INTEREST 

 

No conflict of interest associated with this work.

 

AUTHOR’S CONTRIBUTIONS 

 

This article is part of a research supervised by Professor Yahya Abdullah Ahmed Al-Hadi. Nashwan Yahya Al-Shamahi contributed to the examination of orthopedic images, and Professor Hassan Al-Shamahy is the one who conceived the subject, wrote a draft of the manuscript and analyzed the data.

 

REFERENCES 

 

  1. Park YB, Jeon HS, Shim JS, Lee KW, Moon HS. Analysis of the anatomy of the maxillary sinus septum using 3-dimensional computed tomography. J Oral Maxillofac Surg 2011; 69(4):1070-8.https://doi.org/10.1016/j.joms.2010.07.020
  1. Pommer B, Ulm C, Lorenzoni M, Palmer R, Watzek G, Zechner W. Prevalence, location and morphology of maxillary sinus septa: systematic review and meta-analysis. J Clin Periodontol 2012; 39(8):769–73. https://doi.org/10.1111/j.1600-051X.2012.01897.x
  1. Rysz M, Bakoń L. Maxillary sinus anatomy variation and nasal cavity width: structural computed tomography imaging. Folia morphologica 2009; 68(4):260–4.
  2. Von Arx T, Fodich I, Bornstein MM, Jensen SS. Perforation of the sinus membrane during sinus floor elevation: A retrospective study of frequency and possible risk factors. Int J Oral Maxillofac Implants 2014; 29(3):718-26.https://doi.org/10.11607/jomi.3657
  1. Dandekeri SS, Hegde C, Kavassery P, Sowmya MK, Shetty B. CBCT study of morphologic variations of maxillary sinus septa in relevance to sinus augmentation procedures. Ann Maxillofac Surg 2020; 10(1):51–6.https://doi.org/10.4103/ams.ams_141_19 
  1. Koymen R, Gocmen-Mas N, Karacayli U, Ortakoglu K, Ozen T, Yazici AC. Anatomic evaluation of maxillary sinus septa: Surgery and radiology. Clin Anat 2009; 22(5):563–70.https:/doi.org/10.1002/ca.20813
  1. Vinter I, Krmpotić-Nemanić J, Hat J, Jalsovec D. Does the alveolar process of the maxilla always disappear after tooth loss? Laryngorhinootologie 1993 Dec; 72(12):605–7.https://doi.org/10.1055/s-2007-997963
  1. Krennmair G, Ulm C, Lugmayr H. Maxillary sinus septa: incidence, morphology and clinical implications. J Craniomaxillofac Surg 1997; 25(5):261–5.https://doi.org/10.1016/s1010-5182(97)80063-7.
  1. Shen EC, Fu E, Chiu TJ, Chang V, Chiang CY, Tu HP. Prevalence and location of maxillary sinus septa in the Taiwanese population and relationship to the absence of molars. Clin Oral Implants Res 2012; 23(6):741–5.https://doi.org/10.1111/j.1600-0501.2011.02195.x 
  1. Abbas AM, Al-Kibsi TAM, Al-Akwa AAY, AL-Haddad KA, Al-Shamahy HA, Al-labani MA. Characterization and antibiotic sensitivity of bacteria in orofacial abscesses of odontogenic origin. Universal J Pharm Res 2020; 5(6):36-42.https://doi.org/10.22270/ujpr.v5i6.510
  2. Al-Akwa AA, Zabara A, Al-Shamahy HA, et al. Prevalence of Staphylococcus aureus in dental infections and the occurrence of MRSA in isolates. Universal J Pharm Res 2020; 5(2):1-6. https://doi.org/10.22270/ujpr.v5i2.384 
  3. Al-awadi, TAM, Al-haddad KA, Al-labani M, Al-Shamahy HA, Shaga-aldeen HM. Prevalence of malocclusion among Yemeni children of primary schools. Universal J Pharm Res 2020; 5(1):1-6. https://doi.org/10.22270/ujpr.v5i1.355
  4. AL-Haddad KA, Ali Al-Najhi MM, Al-Akwa AAY, et al. Antimicrobial susceptibility of Aggregatibacter actinomyce-temcomitans isolated from Localized Aggressive Periodontitis (LAP) Cases. J Dent Ora Heal Ad Re 2007; 103. https://doi.org/10.1111/j.1600-0463.2007.apm_630.x 
  5. Al-Haddad KA, Al-Najhi MMA, Abbas AKM, Al-Akwa AAY, Al-Shamahy HA, Al-labani MA. Clinical features, age and sex distributions, risk factors and the type of bacteria isolated in periodontitis patients in Sana'a, Yemen. Universal J Pharm Res 2021; 6(1):1-8.https://doi.org/10.22270/ujpr.v6i1.532 
  6. Alhadi Y, Al-Shamahy HA, Aldilami A, Al-Hamzy M, Al-Haddad KA, et al. Prevalence and pattern of third molar impaction in sample of Yemeni adults. On J Dent Oral Health 2019; 1(5):1-6.https://doi.org/10.33552/OJDOH.2019.01.000523 
  7. Alhadi Y, Rassem AH, Al-Shamahy HA, Al-Ghaffari KM. Causes for extraction of permanent teeth in general dental practices in Yemen. Universal J Pharm Res 2019; 4(2): 1-6. https://doi.org/10.22270/ujpr.v4i2.249
  8. Alhasani AH, Ishag RA, Yahya Al-Akwa AAY, et al. Association between the Streptococcus mutans biofilm formation and dental caries experience and antibiotics resistance in adult females. Universal J Pharm Res 2020; 5(6):1-3. https://doi.org/10.22270/ujpr.v5i5.478 
  9. Alsamhari MMA, AlKhawlani MML, Al-Shamahy HA, et al. Antimicrobial activity of Sodium hypochlorite, nano Silver and Chlorhexidine against mono-species biofilms of selected microorganisms of oral sources. Universal J Pharm Res 2022; 7(1):11-16. https://doi.org/10.22270/ujpr.v7i1.716
  10. Al-Kasem MA, Al-Shamahi NYA, Al-Shamahy HA, Al-Akwa AAY, Al-labani MA. Panorama-Radiographic Assessment of Impacted Teeth and Associated Pathosis Among Selected Males in Sana’a City, Yemen. J Dent Ora Heal Ad Re: JDOHAR 2020;:101
  11. Alsamhari MMA, Al-Najhi MMA, Al-Shamahy HA, Al-dossary OAI. Analysis of biofilms for Streptococcus mutans from dental root surfaces of adult patients with root caries. Universal J Pharm Res 2021; 6(5):19-23.https://doi.org/10.22270/ujpr.v6i5.668 
  12. Al-Shamahi NY, Abbas AM, Al-Shamahy HA, et al. Panoramic Radiographic Analysis of Signs of Proximity to the Third Molar Roots of the Mandibular Canal in Yemen. J Med Clin Case Rep 2020; 2(3): 1-7.
  13. Al-Shamahi NYA, Abbas Al-Kasem M, Al-Shamahy HA, Al-Akwa AAY, Al-Ghaffari KM, Al-Mortada AM, Al-labani MA. Radiographic assessment of the course and visibility of the mandibular canal by panoramic radiography. Universal J Pharm Res 2020; 5(5):17-20.https://doi.org/10.22270/ujpr.v5i5.481
  14. Al-Shamahy HA, Abbas AMA, Mahdie Mohammed AM, Alsameai AM. Bacterial and Fungal Oral Infections Among Patients Attending Dental Clinics in Sana’a City-Yemen. On J Dent Oral Health 2018; 1(1): 1-6.https://doi.org/10.33552/OJDOH.2018.01.000504 
  15. Al-Shami IZ, Al-Shamahy HA, Abdul Majeed ALA, Al- Ghaffari KM and Obeyah AA. Association between the salivary Streptococcus Mutans levels and dental caries experience in adult females. On J Dent Oral Health 2018; 1(1):1-5. https://doi.org/10.33552/OJDOH.2018.01.000505 
  16. Bamashmoos, KAO, Alhasani AH, Al-Akwa AAY, Al-Shamahy HA et al. Prevalence of premature loss of primary teeth at the age of 6-10 years in Sana’a city, Yemen. Universal J Pharm Res 2020; 5(4):1-6.https://doi.org/10.22270/ujpr.v5i4.439
  17. Dahaq WAM, Al-Kholani AIM, Al-Kibsi TAM, Al-Deen HS, Al-Shamahy HA, AL-Haddad KA, Al-Akwa AAY, Al-labani MA. Tanaka and Johnston's mixed dentition validity: an analysis among Yemeni adults in Sana'a city. Universal J Pharm Res 2021; 6(6):1-5.https://doi.org/10.22270/ujpr.v6i6.691 
  18. Gylan EMA, Muharram BA, Al-Shamahy HA, et al. In vitro evaluation of the antimicrobial activity of five herbal extracts against Streptococcus mutans. Universal J Pharm Res 2022; 7(1):1-6. https://doi.org/10.22270/ujpr.v7i1.721
  19. Mutaher NJA, AL-Haddad KA, Al-Shamahy HA, et al. Prevalence and causes of traumatic dental injuries to anterior teeth among primary school children in Sana'a city, Yemen. Universal J Pharm Res 2020; 5(3):38-43.https://doi.org/10.22270/ujpr.v5i3.329
  20. Shogaa Al-Deen SH, Al-Ankoshy AAM, Al-Najhi MMA, Al-Shamahy HA, et al. Porphyromonas gingivalis: biofilm formation, antimicrobial susceptibility of isolates from cases of Localized Aggressive Periodontitis (LAP). Universal J Pharm Res 2021; 6 (4): 1-6.https://doi.org/10.22270/ujpr.v6i4.633 
  21. Yehia LAB, AL-Haddad KA, Al-labani MA, Al-Shamahy HA, Shaga-aldeen HM. Occlusal characteristics of the primary dentition among a sample of Yemeni pre-school children. Universal J Pharm Res 2020; 5(1):1-6. https://doi.org/10.22270/ujpr.v5i1.359
  22. Neupane K, Dhami B, Pandey N.Maxillary Sinus Septa: Prevalence and variation with gender and location. J Nepalese Soc Periodontol Oral Implantol 2021; 5(2): 10.
  23. Lopes LJ, Gamba TO, Bertinato JVJ, Freitas DQ. Comparison of panoramic radiography and CBCT to identify maxillary posterior roots invading the maxillary sinus. Dentomaxillofac Radiol 45(6):2016; 0043.https://doi.org/10.1259/dmfr.20160043
  24. Samara O, Mujalli M, Al Ryalat N, et al. Maxillary sinus septa; prevalence, location, and relation to maxillary sinusitis. Research 2016.https://doi.org/10.13140/RG.2.1.1766.8720 
  25. Van Zyl AW, van Heerden WF. A retrospective analysis of maxillary sinus septa on reformatted computerised tomography scans. Clin Oral Implants Res 2009; 20(12):1398-401.https://doi.org/10.1111/j.1600-0501.2009.01802.x
  26. Yang HM, Bae HE, Won SY, Hu KS, Song WC, Paik DJ, et al. The buccofacial wall of maxillary sinus: an anatomical consideration for sinus augmentation. Clin Implant Dent Relat Res 2009; 11 Suppl 1:e2-6. https://doi.org/10.1111/j.1708-8208.2009.00138.x
  27. Al-Zahrani MS, Al-Ahmari MM, Al-Zahrani AA, Al-Mutairi KD, Zawawi KH. Prevalence and morphological variations of maxillary sinus septa in different age groups: a CBCT analysis. Ann Saudi Med 2020 May; 40(3):200–6.https://doi.org/10.5144/0256-4947.2020.200
  28. Orhan K, Kusakci Seker B, Aksoy S, Bayindir H, Berberoğlu A, Seker E. Cone beam CT evaluation of maxillary sinus septa prevalence, height, location and morphology in children and an adult population. Med Princ Pract 2013; 22(1):47–53. https://doi.org/10.1159/000339849 
  29. Malec M, Smektala T, Tutak M, Trybek G, Sporniak-Tutak K. Maxillary sinus septa prevalence and morphology: computed tomography based analysis. Int J Morphol 2015; 33(1):144–8.
  30. Jain V, Mathur VP, Pillai RS, Kalra S. A preliminary study to find out maximum occlusal bite force in Indian individuals. Indian J Dent Res 2014 Jun; 25(3):325–30.
  31. Kannaperuman J, Natarajarathinam G, Rao AV, Muthusamy N. Cross-sectional study estimating prevalence of maxillary sinus septum in South Indian population. J Dent Implant 2015; 5(1):16–8. https://doi.org/10.4103/0974-6781.154423 
  32. Kocak N, Alpoz E, Boyacıoglu H. Morphological assessment of maxillary sinus septa variations with cone-beam computed tomography in a Turkish population. Eur J Dent 2019; 13(1):42–6.https://doi.org/10.1055/s-0039-1688541 
  33. Selcuk A, Ozcan KM, Akdogan O, Bilal N, Dere H. Variations of maxillary sinus and accompanying anatomical and pathological structures. J Craniofac Surg 2008; 19(1):159–64. https://doi.org/10.1097/scs.0b013e3181577b01
  34. Jang SY, Chung K, Jung S, Park HJ, Oh HK, Kook MS. Comparative study of the sinus septa between dentulous and edentulous patients by cone beam computed tomography. Implant Dent 2014; 23(4):477–81.https://doi.org/10.1097/ID.0000000000000107
  35. Çakur B, Sümbüllü MA, Durna D. Relationship among schneiderian membrane, under wood’s septa, and the maxillary sinus inferior border. Clin Implant Dent Relat Res 2013; 15(1):83–7.https://doi.org/10.1111/j.1708-8208.2011.00336.x
  36. Schwartz-Arad D, Herzberg R, Dolev E. The prevalence of surgical complications of the sinus graft procedure and their impact on implant survival. J Periodontol 2004; 75(4):511–6.https://doi.org/10.1902/jop.2004.75.4.511