Assessments of Prevalence of Ponticulus Posticus, Atlas Posterior Arch Deficiency, Sella Turcica Bridging, Maxillary Canine Impaction, and Associations Among Them in 500 CBCTs of Italian Orthodontic Patients

Abstract

Background: The ponticulus posticus (PP) is an important anomaly of the atlas (C1 vertebra) with a complete or partial bone bridge that transforms the groove of the vertebral artery (VA) into a canal (arcuate foramen). The aim was to retrospectively determine prevalence of PP evaluating morphological features and the possible association with other dentoskeletal anomalies in the midface and neck area such as maxillary canine impaction (MCI), atlas posterior arch deficiency (APAD), and sella turcica bridging (SB).Methods: This study was conducted in the Department of Medical, Oral and Biotechnological Sciences of the University “G. D'Annunzio” in Chieti. The detection of PP was performed on 500 patients with cone beam CT (CBCT) images (6 to 87 years).Results: Analysis revealed the presence of uni- and bi-lateral PP in 110 patients (22%): 24 (4.8%) patients with bilateral complete PP, 12 (2.4%) patients with complete PP on the left, 6 (1.2%) patients with complete PP on the right, 8 (1.6%) patients with complete PP on the right and partial PP on the left, 6 (1.2%) patients with complete PP on the left and partial PP on the right, 26 (5.2%) patients with partial bilateral PP, 18 (3.6%) patients with partial left PP, and 10 (2%) patients with partial PP on the right. The Chi-squared statistic confirmed that there are significant associations between MCI and PP (p = 0.020) and between SB and MCI (p <0.00001). No correlation between chronological age and presence of the PP (p = 0.982), between chronological age and morphotypes of the PP (p = 0.779), between APAD and the PP (p = 0.0757), between SB and the PP (p = 0.111), and between APAD and MCI (p = 0.222) were found.Conclusion: This observational study showed how bilateral partial variant and bilateral complete variant are the most represented morphotypes in all the age groups. The prevalence of MCI is positively associated with PP and with SB.

Prevalence of Ponticulus Posticus and Migraine in 220 Orthodontic Patients: A Cross-Sectional Study

“…Since the prevalence of PP is not correlated with gender or sex, as found in the literature, the present paper did not investigate this aspect [ 28 ].…”

A New Classification of the Morphology of Complete Ponticulus Posticus on Cone Beam Computed Tomography

“…PP also has multiple other names in the medical literature, such as dorsal or posterior ponticle [ 1 ], posterior ponticulus [ 4 ], pons posticus [ 1 ], pons ponticus [ 4 ], sagittal foramen [ 1 , 5 , 6 , 7 ], atlantal posterior foramen [ 5 ], foramen atlantideum [ 1 , 8 ], foramen atlantoideum posterior [ 6 , 7 ], posterior atlantoid foramen, [ 4 ], arcuate foramen [ 1 , 4 , 5 , 7 , 8 ], arcuale foramen [ 1 , 6 , 7 ], atlas bridging [ 4 , 8 ], a variant of Kimmerle’s anomaly [ 1 , 5 , 6 , 7 ], upper retroarticular foramen, [ 5 ], retroarticular canal [ 5 , 6 ], retroarticular foramen [ 4 , 8 ], foramen retroarticulare superior [ 6 ], retroarticular canal of the atlas [ 1 ], canalis vertebralis [ 1 , 5 , 6 , 7 , 8 ], canalis arteriae vertebralis [ 4 ], retroarticular vertebral artery ring [ 1 , 4 , 5 , 6 ], retrocondylar vertebral artery ring [ 5 , 6 ,…”

“…PP represents the ossification at the edge of the lateral atlantooccipital membrane, which is inserted on the occipital bone and on the edge of the posterior arch of the atlas [ 9 , 10 ]. Many hypotheses exist to explain the ossification of this membrane, such as congenital [ 4 , 6 , 11 ], genetic mutation [ 4 , 6 , 12 ], post-traumatic genesis [ 12 ], human evolution [ 12 ] with a protective role to the vertebral artery passage during head and neck movements [ 4 ], the result of ossification due to aging [ 4 , 6 ], and due to external mechanical factors [ 6 ] such as carrying heavy objects on the head [ 4 ].…”

“…PP surrounds the vertebral artery, periarterial plexus [ 5 ], and the suboccipital nerve [ 4 ]. The compression of one or more neural and vascular structures, including vertebral artery, periarterial plexus, and sub-occipital nerve passing under the PP [ 3 , 4 , 10 ], may explain the presence of diverse symptoms including muscle tension headache [ 4 , 6 , 12 ], cervical migraine [ 3 , 5 , 10 , 13 ], migraine without aura [ 8 ], migraine-like headache [ 2 ], cochlear symptoms (tinnitus and hearing loss) [ 12 ], neurosensory-type hearing loss [ 3 , 4 , 5 , 6 , 10 ], vestibular symptoms (subjective vertigo [ 2 , 3 , 5 , 6 , 8 , 10 , 12 ]), dizziness [ 4 ], ocular symptoms (convergence deficit) [ 12 ], diplopia [ 8 ], throat disorders (dysphagia, dysphonia) [ 12 ], cervicobrachial syndrome [ 12 ], neck pain [ 2 , 3 , 4 , 5 , 6 , 8 , 10 ], shoulder–arm pain [ 3 , 4 , 5 , 6 ], loss of postural muscle tone [ 3 , 4 , 5 ,…”

“…More recent studies have implemented cone beam computed tomography (CBCT) [ 19 ]. Nonetheless, the application of two-dimensional (2D) technologies (lateral X-rays) falls short in accurately assessing the morphological attributes and symmetry anomalies of PP [ 4 ]. Presently, CBCT is recognized as the gold standard in the radiodiagnosis of the PP, facilitating three-dimensional (3D) classification [ 4 , 15 ].…”