The prevalence of persistence metopic suture (metopisim) among Kurdish populations of Erbil city.


  • Soran M Karim Department of Oral and Maxillofacial Surgery, College of Dentistry, Hawler Medical University, Erbil, Iraq.
  • Othman Omar Department of Oral and Maxillofacial Surgery, College of Dentistry, Hawler Medical University, Erbil, Iraq.
  • Muyesser Nuri Department of Pediatric Medicine, college of Medicine/Hawler Medical University.
  • Tuqa Yousif Al-Sharef Department of basic sciences/ College of dentistry/Hawler Medical University.



Prevalence, Metopisim, Inter-frontal suture, anatomical variations, Kurdish peoples


Background and objective: A fully developed frontal bone consists mainly of two portions separated by a vertically oriented suture called metopic, frontal or inter-frontal suture, it’s considered to be the first skull suture to close metopic suture physiologically closes at different times of age and could occur from birth through age 8 years,In some individual (and as a normal variant) a persistent metopic suture can be seen in the midline running down the frontal bone and the condition is referred to as metopisim. The study aims to investigate the prevalence of metopisim among the Kurdish population of Erbil city,type of metopisim, gender and/or environmental or racialimpact will also be assessed.

 Methods: This retrospective/radiological study was conducted on conveniently selected PA (Caldwell view) plain radiographic images of 613 Kurdish individuals of mixed genders, ages ranging between 10 to 64 years and images were taken from the periods between April 2020 to May 2022 for various medical reasons but mostly were for assessment of blunt head trauma.

Results:Out of 613 assessed P.A. radiographs only in 17 cases showed the presence of metopisim, (12 females and 5 males), metopisim was of complete type in just 4 cases; 3 were females and just 1 of them was a male case and it was incomplete in 13 of the cases; 9 females and just 4 were among males.

Conclusion: It’s of crucial importance to identify the metopic suture persistence and its interracial and ethnic diversity as its existence presence could be mistaken and misdiagnosed as a vertical or an oblique cranial fracture upon assessments of radiological images.

Keywords: Prevalence, Frontal bone, Metopisim, Metopic suture, Frontal suture, Inter-frontal suture, Kurdish peoples, anatomical variations.


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How to Cite

Karim SM, Omar O, Nuri M, Al-Sharef TY. The prevalence of persistence metopic suture (metopisim) among Kurdish populations of Erbil city. EDJ [Internet]. 2023 Jun. 30 [cited 2024 May 18];6(1):104-12. Available from:



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