|Year : 2022 | Volume
| Issue : 1 | Page : 35-39
Correlation of ponticulus posticus with dentofacial skeletal patterns
Sepideh Falah-Kooshki1, Nafiseh Nikkerdar1, Mohammad Moslem Imani2, Reza Faraji3, Amin Golshah2
1 Department of Oral and Maxillofacial Radiology, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
2 Department of Orthodontic, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
3 Student Research Committee, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
|Date of Submission||11-Jul-2020|
|Date of Decision||13-Aug-2020|
|Date of Acceptance||31-Dec-2020|
|Date of Web Publication||23-Mar-2022|
Dr. Amin Golshah
Department of Orthodontic, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: This study aimed to assess the correlation of ponticulus posticus (PP) with dentofacial skeletal patterns on lateral cephalograms of an Iranian population. Methods: This retrospective study evaluated 1000 lateral cephalograms of 690 females and 310 males. Demographic information of patients was recorded, and two observers evaluated all radiographs for the presence of PP. The dentofacial skeletal pattern was also determined as Class I, II, or III. Disagreements were resolved by discussion with a third observer. Data were analyzed using the Chi-square test. Results: The mean age of patients was 19.47 ± 8.37 years (range 7–64 years). The prevalence of PP was 38.3%. PP had a significant correlation with gender (P = 0.022) such that PP was more common in males (43.5%). No significant correlation was noted between PP and age or dentofacial skeletal pattern (P > 0.05). Conclusions: PP was relatively common in our study population. PP had no correlation with age or dentofacial skeletal pattern of patients.
Keywords: Arcuate foramen, atlas, dentofacial skeletal pattern, lateral cephalometry, ponticulus posticus
|How to cite this article:|
Falah-Kooshki S, Nikkerdar N, Imani MM, Faraji R, Golshah A. Correlation of ponticulus posticus with dentofacial skeletal patterns. Contemp Clin Dent 2022;13:35-9
| Introduction|| |
The atlas is the first (most superior) cervical vertebra of the spine, which can have morphological variations and characteristics that distinguish it from the other vertebrae. Ponticulus posticus (PP) is a small abnormal posterior bridge, which forms between the posterior segment of the superior articular eminence and the posterolateral part of the superior margin of the posterior arch of the atlas. PP is also known as the arcuate foramen, foramen arcuate atlantis, posterior ponticle, or Kimerle anomaly. It can completely or partially surround the vertebral artery and the first cervical nerve root., It reportedly has a prevalence of 1.3%–45.9%, and its prevalence is not significantly different between males and females. This anomaly is bilateral in 5.4% and unilateral in 7.5% of the patients.,,,,,,,,
It has been reported that some conditions such as headache, neck pain, migraine without aura, initiation of hearing loss, photophobia, and tension-type chronic headaches are related to the presence of PP.,,, Furthermore, it is important to identify PP to determine the site of entry of screw to the lateral masses of atlas because some surgeons have pointed to the risk of acute complications such as traumatization of the vertebral artery in surgical procedures of this region.
Lateral cephalometry is highly popular in orthodontics. Cephalometric radiographs are requested to evaluate the stage of skeletal maturation and dentofacial skeletal pattern. However, they can also provide other diagnostic information about the cranium and cervical vertebra and the craniofacial and dental variations.,,,,, Such information may be valuable for early detection of developmental problems.,, The variations in shape, size, form, and contour of anatomical landmarks are multiple and confusing. Thus, care must be taken to precisely assess these anatomical variations in different populations.
Correlations have been reported between the morphology of the vertebral column and position of the mandible., This relationship may be based on the involvement of neural crest cells and/or homeobox or hox genes during growth and development stage, affecting tooth formation and eruption, cervical vertebra, and jaws development.,
There is a gap of information regarding the prevalence of PP in Iran and its correlation with dentofacial skeletal patterns.,, Thus, this study aimed to assess the correlation of PP with dentofacial skeletal patterns on lateral cephalograms of an Iranian population.
This descriptive, cross-sectional study evaluated the lateral cephalograms of patients retrieved from the archives of three private orthodontic offices in Kermanshah city. The study protocol was approved by the institutional review board of Kermanshah University of Medical Sciences (IR.KUMS.REC.1397.049).
Sample size was calculated to be 1000 according to a study by Adisen and Misirlioglu that reported the prevalence of PP to be 22.8% and 15.9% in males and females, respectively, assuming alpha = 0.05, power of 90%, and accuracy (d) of 0.085. Lateral cephalograms were selected using convenience sampling.
Lateral cephalograms had been taken from January 2016 to July 2018 for orthodontic treatment planning and diagnostic purposes. The pretreatment radiographs of three private orthodontic offices were searched randomly until the desired number of eligible cephalograms was reached.
All 1136 lateral cephalograms of patients between 18 and 25 years were first retrieved. Of all, 136 lateral cephalograms were excluded due to the invisibility of PP or other cephalometric points, wrong head posture, and blurring.
All cephalograms had been taken with teeth in occlusion, lips at rest, and head in standard position (Frankfurt plane parallel to the horizontal plane) by an experienced technician using Soredex (Helsinki, Finland) cone-beam computed tomography (CBCT) scanner with the exposure settings of 73 kVp, 10 mA, and 11 s. The lateral cephalograms were saved in JPEG format and displayed on a 14-inch laptop monitor with 300 dpi resolution in a semi-dark room.
For each lateral cephalogram, demographic information of patient (age and gender), presence/absence of PP, its level of development if PP was present (complete or partial), and dentofacial skeletal pattern were all recorded.
Development of PP on the atlas was classified as (I) absence of any bony process, (II) incomplete formation of PP, or (III) complete formation of a bony bridge [Figure 1].
|Figure 1: Development of ponticulus posticus. (a) Complete ponticulus posticus, (b) incomplete ponticulus posticus|
Click here to view
The dentofacial skeletal pattern [Figure 2] was determined by an orthodontist based on the ANB angle and the Wits appraisal. The skeletal pattern was categorized as Class I when the ANB angle was 0° ± 2° and the Wits appraisal was 4 mm, Class II when the ANB angle was >4° and the Wits appraisal was >4 mm, and Class III when the ANB angle was <0° and the Wits appraisal was <0 mm.,
|Figure 2: Skeletal relationship in the sagittal plane to determine the dentofacial skeletal pattern according to the Angle's classification|
Click here to view
All cephalograms were evaluated for the presence of PP by an expert oral and maxillofacial radiologist and an expert orthodontist. Disagreements were resolved by discussion with a third observer. Furthermore, 20% of cephalograms were evaluated again by one of the observers. To assess the intraobserver agreement, all cephalograms were assessed again for the presence of PP and its development, and other measurements were repeated again after 2 weeks by the same observers, and the results of the first and second observations were compared.
Data were analyzed using SPSS version 25 (SPSS Inc., IL, USA). The Chi-square test was used to compare the presence of PP between males and females, age groups, and dentofacial skeletal patterns. Level of significance was set at 0.05.
| Results|| |
This study evaluated the lateral cephalograms of 690 females (69%) and 310 males (31%) with a mean age of 21.61 ± 2.21 years. [Table 1] shows the prevalence of PP and dentofacial skeletal pattern of subjects.
|Table 1: Prevalence and type of ponticulus posticus and dentofacial skeletal pattern|
Click here to view
No significant correlation was noted between the prevalence of PP and dentofacial skeletal pattern (P = 0.571). No significant correlation was noted between the type of PP and dentofacial skeletal pattern either [P = 0.565, [Table 2]].
|Table 2: Prevalence and type of ponticulus posticus based on dentofacial skeletal pattern|
Click here to view
A significant correlation was noted between gender and PP (P = 0.022) such that the prevalence of PP was higher in males. The prevalence of complete PP was also higher in males; although the correlation between the type of PP and gender was not significant [P = 0.057, [Table 3]].
The maximum prevalence of PP in females was in Class II patients, while the maximum prevalence of PP in males was in Class I patients. The highest prevalence of complete PP in females was recorded in Class I patients, while the highest prevalence of complete PP in males was recorded in Class II patients [Table 4].
|Table 4: Prevalence of ponticulus posticus based on gender and dentofacial skeletal pattern|
Click here to view
| Discussion|| |
This study assessed the correlation of PP with dentofacial skeletal patterns on lateral cephalograms of an Iranian population.
Development of PP was classified as absence of PP, complete PP, and partial PP. The prevalence of PP was found to be 38.3%. No significant correlation was noted between PP and dentofacial skeletal pattern or age, but PP and gender were significantly correlated, and its prevalence was 43% in males and 35.9% in females. Previous studies have reported the prevalence of PP to be 4.3%–46%.,,,,,,,, Such differences can be due to the methodology, type and number of samples, and different inclusion and exclusion criteria. Higher prevalence of PP in our study compared with the studies by Sharma et al., and Mudit et al. were due to larger sample size, wide age range, and racial differences among patients. In a meta-analysis, Elliott and Tanweer indicated that the accuracy of assessment of corpse was higher than that of computed tomography (CT), and the accuracy of CT was higher than that of lateral cephalometry for this purpose. This finding can also explain the difference in prevalence values of PP in different studies.
In our study, the prevalence of complete and partial PP was 40.2% and 59.8%, respectively, and PP was significantly more common in males than females (43.5% vs. 35.9%, respectively). No significant correlation was noted between the type of PP (partial/complete) and gender, age, or dentofacial skeletal pattern. However, the complete type was more common in male Class II patients, while the partial type was more common in female Class II patients. Adisen and Misirlioglu in a similar study found no significant difference between the prevalence of partial and complete types based on gender or dentofacial skeletal pattern of patients.
Some studies have demonstrated a correlation between anomalies of the cervical vertebrae and mandibular position.,, We found no significant correlation between PP and dentofacial skeletal pattern. Adisen and Misirlioglu reported that PP was more common in Class III patients, followed by Class I and Class II patients; however, this difference was not significant, and this finding was in line with our results. Kamak and Yildirim evaluated anomalies of the cervical vertebrae among different classes of occlusion and found no significant association in this respect. Haji Ghadimi et al. showed that PP was not correlated with Class I or Class II malocclusion. However, they failed to find a significant correlation between Class III malocclusion and PP. They explained that not finding a significant correlation was due to small number of Class III patients in their study. We found the same results despite the fact that we had a larger sample size than theirs.
Considering the significance of PP and its relatively high prevalence in the Iranian population residing in the West of Iran (38.3%), it is recommended to evaluate PP on lateral cephalograms before surgical procedures of the first cervical vertebra. In case of visualization of PP, three-dimensional (3D) imaging can be requested to determine its exact size and shape.
This study had some limitations with regard to the use of lateral cephalometry. Although lateral cephalometry is an efficient tool for the detection of PP, previous studies using both lateral cephalometry and CT scan have reported significantly higher prevalence of PP and partial bridges on 3D CT scans., These findings suggest that one-dimensional radiography may underestimate the prevalence of PP. Moreover, lateral cephalometry cannot help in determination of unilateral or bilateral presence of PP, and the 3D morphology of PP cannot be reconstructed. Future multicenter studies using CBCT or CT are required to confirm and validate the findings of this study.
Last but not least, this study had a retrospective design and we had no information about pain in patients to assess the relationship of the presence of PP and facial pain.
| Conclusions|| |
Based on the results of this study, there is no significant correlation between the occurrence or type (partial/complete) of PP and gender or dentofacial skeletal pattern of patients.
Financial support and sponsorship
This study was derived from a thesis, submitted to Kermanshah University of Medical Sciences, School of Dentistry and was financially supported from the Kermanshah University of Medical Sciences, Kermanshah, Iran.
Conflicts of interest
There are no conflicts of interest.
| References|| |
Buyuk SK, Sekerci AE, Benkli YA, Ekizer A. A survey of ponticulus posticus: Radiological analysis of atlas in an orthodontic population based on cone-beam computed tomography. Niger J Clin Pract 2017;20:106-10.
] [Full text]
Adisen MZ, Misirlioglu M. Prevalence of ponticulus posticus among patients with different dental malocclusions by digital lateral cephalogram: A comparative study. Surg Radiol Anat 2017;39:293-7.
Gibelli D, Cappella A, Cerutti E, Spagnoli L, Dolci C, Sforza C. Prevalence of ponticulus posticus in a Northern Italian orthodontic population: A lateral cephalometric study. Surg Radiol Anat 2016;38:309-12.
Chitroda PK, Katti G, Baba IA, Najmudin M, Ghali SR, Kalmath B, et al
. Ponticulus posticus on the posterior arch of atlas, prevalence analysis in symptomatic and asymptomatic patients of gulbarga population. J Clin Diagn Res 2013;7:3044-7.
Hasani M, Shahidi S, Rashedi V, Hasani M, Hajiyan K. Cone beam CT study of ponticulus posticus: Prevalence, characterictics. Biomed Pharmacol J 2016;9:1067-72.
Ziabari SM, Asadi P, Ansar MM, Razzaghi A, Monsef Kasmaei V. Prevalence of arcuate foramen among emergency department visitors; An epidemiologic study. Iranian J Emerg Med 2017;4:46-51.
Kim KH, Park KW, Manh TH, Yeom JS, Chang BS, Lee CK. Prevalence and morphologic features of ponticulus posticus in Koreans: Analysis of 312 radiographs and 225 three-dimensional CT scans. Asian Spine J 2007;1:27-31.
Ali B, Shaikh A, Fida M. Association between sella turcica bridging and palatal canine impaction. Am J Orthod Dentofacial Orthop 2014;146:437-41.
Mudit G, Srinivas K, Satheesha R. Retrospective analysis of ponticulus posticus in Indian orthodontic patients-a lateral cephalometric study. Ethiop J Health Sci 2014;24:285-90.
Sekerci AE, Soylu E, Arikan MP, Aglarci OS. Is there a relationship between the presence of ponticulus posticus and elongated styloid process? Clin Imaging 2015;39:220-4.
Leonardi R, Barbato E, Vichi M, Caltabiano M. Skeletal anomalies and normal variants in patients with palatally displaced canines. Angle Orthod 2009;79:727-32.
Leonardi R, Barbato E, Vichi M, Caltabiano M. A sella turcica bridge in subjects with dental anomalies. Eur J Orthod 2006;28:580-5.
Sonnesen L, Kjaer I. Cervical column morphology in patients with skeletal Class III malocclusion and mandibular overjet. Am J Orthod Dentofacial Orthop 2007;132:427.e7-12.
Becktor JP, Einersen S, Kjaer I. A sella turcica bridge in subjects with severe craniofacial deviations. Eur J Orthod 2000;22:69-74.
Sonnesen L, Kjaer I. Cervical vertebral body fusions in patients with skeletal deep bite. Eur J Orthod 2007;29:464-70.
Giri J, Pokharel PR, Gyawali R. How common is ponticulus posticus on lateral cephalograms? BMC Res Notes 2017;10:172.
Tambawala SS, Karjodkar FR, Sansare K, Motghare D, Mishra I, Gaikwad S, et al
. Prevalence of ponticulus posticus on lateral cephalometric radiographs, its association with cervicogenic headache and a review of literature. World Neurosurg 2017;103:566-75.
Bui C, King T, Proffit W, Frazier-Bowers S. Phenotypic characterization of Class III patients. Angle Orthod 2006;76:564-9.
Lippold C, Danesh G, Hoppe G, Drerup B, Hackenberg L. Sagittal spinal posture in relation to craniofacial morphology. Angle Orthod 2006;76:625-31.
Miletich I, Sharpe PT. Neural crest contribution to mammalian tooth formation. Birth Defects Res C Embryo Today 2004;72:200-12.
Matsuoka T, Ahlberg PE, Kessaris N, Iannarelli P, Dennehy U, Richardson WD, et al
. Neural crest origins of the neck and shoulder. Nature 2005;436:347-55.
Eslamipour F, Borzabadi-Farahani A, Le BT, Shahmoradi M. A Retrospective Analysis of Dentofacial Deformities and Orthognathic Surgeries. Ann Maxillofac Surg 2017;7:73-7.
] [Full text]
Jacobson A. The “Wits” appraisal of jaw disharmony. Am J Orthod 1975;67:125-38.
Sharma V, Chaudhary D, Mitra R. Prevalence of ponticulus posticus in Indian orthodontic patients. Dentomaxillofac Radiol 2010;39:277-83.
Kuhta P, Hart J, Greene-Orndorff L, McDowell-Reizer B, Rush P. The prevalence of posticus ponticus: Retrospective analysis of radiographs from a chiropractic health center. J Chiropr Med 2010;9:162-5.
Elliott RE, Tanweer O. The prevalence of the ponticulus posticus (arcuate foramen) and its importance in the Goel-Harms procedure: Meta-analysis and review of the literature. World Neurosurg 2014;82:e335-43.
Hong JT, Lee SW, Son BC, Sung JH, Yang SH, Kim IS, et al
. Analysis of anatomical variations of bone and vascular structures around the posterior atlantal arch using three-dimensional computed tomography angiography. J Neurosurg: Spine SPI, 2008;8:230-6.
Sekerci AE, Soylu E, Arikan MP, Ozcan G, Amuk M, Kocoglu F. Prevalence and morphologic characteristics of ponticulus posticus: Analysis using cone-beam computed tomography. J Chiropr Med 2015;14:153-61.
D'Attilio M, Epifania E, Ciuffolo F, Salini V, Filippi MR, Dolci M, et al
. Cervical lordosis angle measured on lateral cephalograms; findings in skeletal class II female subjects with and without TMD: A cross sectional study. Cranio 2004;22:27-44.
Festa F, Tecco S, Dolci M, Ciufolo F, Di Meo S, Filippi MR, et al
. Relationship between cervical lordosis and facial morphology in Caucasian women with a skeletal class II malocclusion: A cross-sectional study. Cranio 2003;21:121-9.
Kamak H, Yildırım E. The distribution of cervical vertebrae anomalies among dental malocclusions. J Craniovertebr Junction Spine 2015;6:158-61.
Haji Ghadimi M, Amini F, Hamedi S, Rakhshan V. Associations among sella turcica bridging, atlas arcuate foramen (ponticulus posticus) development, atlas posterior arch deficiency, and the occurrence of palatally displaced canine impaction. Am J Orthod Dentofacial Orthop 2017;151:513-20.
Cho YJ. Radiological analysis of ponticulus posticus in Koreans. Yonsei Med J 2009;50:45-9.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4]