eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2016-12-22 9 3 1067 1072 10.13005/bpj/1050 11825 article Mahvash Hasani 1 Shoaleh Shahidi 2 Vahid Rashedi 3 Mahsa Hasani 4 Khadijeh Hajiyan 5 Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. Department of Oral and Maxillofacial Radiology, Biomaterial Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran. Student Research Committee, Shiraz University of Medical Science, Shiraz, Iran. Department of oral Medicine, School of Dentistry, Isfahan University of Medical Science,Isfahan Iran. Ponticulus posticus has become an important anomaly of the atlas as a reason of Migrane without headache, vertebrobasilar insufficiency symptoms such as headache, shoulder pain, vertigo and diplopia. Since the last two decades, the presence of Ponticulus posticus has received a lot of attention, mainly because of its clinical significance. The aim of this study was to scrutinize the prevalence, bilaterality and dimension of ponticulus posticus as a bony arch on the posterolateral aspect of the posterior arch atlas in Iranian population. The 233 CBCTs were evaluated to feature the presence of ponticulus posticus. This abnormality was classified based on completeness (partial and complete group). We measured the size of the foramen in sagittal reformatted plane. Finally, the prevalence by sex and age group was determined.  Assessment of 233 3D CBCT images revealed the presence of ponticulus posticus in 48 patients, including 20.6% of cases, of which 6.4% demonstrated unilateral ponticulus posticus, and the remaining 14.2%, corresponding to 33 cases, who showed bilateral ones. There was no significant difference in ponticulus posticus prevalence among male (P=0.393). The mean height of ponticulus posticus was 5.95 mm (SD 0.7823) and the mean width was 6.52 mm (SD 1.0308). Ponticulus posticus as an important anomaly of atlas seems to be more common in our population than our assumption prior to the investigation. Awareness of this abnormality is a requisite for every clinician who deals with atlantoaxial instability. Owing to opportunity of underestimating, each image should be observed totally by all maxillofacial radiologists and dental professionals who apply CBCT. https://biomedpharmajournal.org/vol9no3/cone-beam-ct-study-of-ponticulus-posticus-prevalence-characterictics/ CBCT Ponticulus posticus Prevalence Dimension