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.

BackgroundThis study aims to evaluate the development and the compensation mechanisms of the mandibular asymmetry in a growing patient, using Cone Beam Computed Tomography (CBCT). In this case, the menton was deviated on the right, an extremely rare condition, which may be the consequence of a disorder in the mandibular growth. Case presentationThe patient was treated with Rapid Palatal Expander (RPE) and Fränkel Functional Regulator III (FR-3). The initial CBCT was acquired at the beginning of therapy, when patient was 8 years old (y.o), the final CBCT was acquired at the end of the treatment, when patient was 12 y.o. Patient’s CBCT was performed with the head oriented according to the Natural Head Position (NHP); the NHP is a physiological and reproducible posture defined for morphological analysis.The 3D image of the cranium was oriented in the Dolphin software according to NHP posture; the cephalometric measurements were performed in frontal, laterolateral right and left, posteroanterior and submentovertex views in the aforementioned software. The therapy lasted 3.8 years and ended with a significant regression of the mandibular asymmetry from moderate grade (4.2 mm) to slight grade (1.3 mm). Conclusion The left hemi-mandible has grown more than right side, in accordance with the literature, which affirm that in case of deviation of the menton greater than 4 mm, the bone volume increases on the nondeviated side.