Medical Journal of the Islamic Republic Of Iran

en Prevalence of Ponticulus Posticus among Orthodontic Patients of Iranian Population by Lateral Cephalogram Epidemiology Epidemiology Original Research: Clinical Science Original Research: Clinical Science Background: The term Ponticulus Posticus (PP) refers to a complete or partial bony bridge on the vertebral artery that passes through the superior-lateral surface of the posterior arch of the atlas. This study was conducted with the aim of investigating the prevalence of ponticulus posticus in orthodontic patients referred to Mashhad Dental School.    Methods: In this cross-sectional study, one thousand cephalograms were selected from the patients referred to the orthodontics department of Mashhad Dental School between 2017 and 2021. In lateral cephalogram images with appropriate quality, the type of malocclusion was determined using the AudaxCeph software (Audax d.o.o., Ljubljana, Slovenia). Then, the images were evaluated for the presence or absence of PP. For the statistical analysis, chi-square and t-test were used.    Results: In this study, 861 lateral digital cephalograms were analyzed. The overall prevalence of PP in the studied population was 17.5%. The prevalence of PP was higher in males than in females (P < 0.001).  The variables “presence of PP” (P = 0.056) and “type of PP” (P = 0.522) were found to be independent of age groups. Although class II subjects showed a higher prevalence of PP, skeletal malocclusion classes were not found to be correlated with the presence of PP (P = 0.104) nor with its types (P = 0.958).    Conclusion: The current study is considered the primary study that provides data concerning the prevalence of PP in the East of Iran. Our study showed that PP was not rare in this region. More studies with 3D radiological examination are needed to increase the accuracy of diagnosing PP and its prevalence in Iran.   Lateral Cephalogram, Ponticulus Posticus, Malocclusion, Radiography 512 517 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-8690-1&slc_lang=en&sid=1 Ali Bagherpour bagherpoura@mums.ac.ir 200319475328460089386 200319475328460089386 No Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran Behzad Motaharian behzadmotaharyan@yahoo.com 200319475328460089387 0009-0004-3777-6192 No Student Research Committee, School of Dentistry, Mashhad University of Medical Science, Mashhad, Iran Farzaneh Lal Alizadeh fla7989@gmail.com 200319475328460089388 200319475328460089388 No Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran Maryam Valizadeh Valizadehmr@mums.ac.ir 200319475328460089389 200319475328460089389 No Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran Kosar Hosseini hoseinik971@ mums.ac.ir 200319475328460089390 200319475328460089390 Yes Student Research Committee, School of Dentistry, Mashhad University of Medical Science, Mashhad, Iran