Does the chin projection and sella point position affect the W angle reliability?

Abstract

Purpose:The purpose of this study was to compare the reliability and validity of the Sella (S) and G points used in the W angle or different types of malocclusions.

Materials and methods:Pretreatment cephalometric radiographs of 700 individuals aged 15 to 25 years, who began orthodontic treatment between 2019 and 2024, were randomly selected from the archives of the Department of Orthodontics at Afyonkarahisar Health Sciences University. After applying exclusion criteria, 570 radiographs (290 females, 280 males) were included in the study. These radiographs were divided into three groups based on ANB and Wits values: Class I (C1) (n = 103), Class II (C2) (n = 178), and Class III (C3) (n = 111). Each group was further divided into nine subgroups according to chin projection (low [a1], normal [a2], high [a3]), the vertical position of the sella point (low [b1], normal [b2], high [b3]), and the sagittal position of the sella point (low [c1], normal [c2], high [c3]). The vertical position of the sella point was determined by calculating its distance from the FH plane, while its sagittal position was assessed by measuring the distance of its projection onto the FH plane relative to the orbitale point. Chin projection was determined using the Pg-NB measurement.

Results: Statistical analysis showed that chin projection was positively correlated with the W angle in all subgroups (p < 0.001). The sagittal position of the sella point did not significantly affect the W angle in any of the classes. However, the vertical position of the sella point was positively correlated with the W angle only in the subgroups with high vertical values (C1b3, p = 0.002; C2b3, p < 0.001; C3b3, p < 0.001).

Conclusion: Both chin projection and the vertical position of the sella point were found to influence the W angle, whereas the sagittal position of the sella point did not have a significant effect.

Keywords

• cephalometric analysis
• w angle
• chin projection
• sella point
• orthodontics

References

1. Elkaseh A, Shayeb MA, Kuduruthullah S, Elsubeihi ES. Cephalometrics of Libyan adults. Asian J Surg 2022;45:1089-94. [CrossRef] google scholar
2. Riedel RA. Esthetics and its relation to orthodontic therapy. Angle Orthod 1950;20:168-78. google scholar
3. Jacobson A. The “Wits” appraisal of jaw disharmony. Am J Orthod 1975;67:125-38. [CrossRef] google scholar
4. Baik CY, Ververidou MA. New approach of assessing sagittal discrepancies: the Beta angle. Am J Orthod Dentofacial Orthop 2004;126:100-5. [CrossRef] google scholar
5. Neela PK, Mascarenhas R, Husain AA. New sagittal dysplasia indicator: the YEN angle. World J Orthod. 2009;10:147-51. google scholar
6. Steiner, CC. Cephalometrics in clinical practice. Angle Orthod 1959;29:8-29. google scholar
7. Kamaluddin JM, Cobourne MT, Sherriff M, Bister D. Does the Eastman correction over- or under-adjust ANB for positional changes of N? Eur J Orthod 2012;34:719-23. [CrossRef] google scholar
8. Nagar S, Nagar R, Raghav P. Why WITS? Why not a way beyond? Contemp Clin Dent 2014;5:518-23. [CrossRef] google scholar

9. Adenwalla ST, Kronman JH, Attarzadeh F. Porion and condyle as cephalometric landmarks--an error study. Am J Orthod Dentofacial Orthop 1988;94:411-5. [CrossRef] google scholar
10. Sundareswaran S, Kumar V. Reliability of Beta angle in assessing true anteroposterior apical base discrepancy in different growth patterns. J Nat Sci Biol Med 2015;6:125-30. [CrossRef] google scholar
11. Bhad WA, Nayak S, Doshi UH. A new approach of assessing sagittal dysplasia: the W angle. Eur J Orthod 2013;35:66-70. [CrossRef] google scholar
12. Trivedi R, Bhattacharya A, Mehta F, Patel D, Parekh H, Gandhi V. Cephalometric study to test the reliability of anteroposterior skeletal discrepancy indicators using the twin block appliance. Prog Orthod 2015;16:4-10. [CrossRef] google scholar
13. Qamaruddin I, Alam MK, Shahid F, Tanveer S, Umer M, Amin E. Comparison of popular sagittal cephalometric analyses for validity and reliability. Saudi Dent J.2018;30:43-46. [CrossRef] google scholar
14. Ali SM, Manjunath G, Sheetal A. A Comparison of 3 New Cephalometric Angles with ANB and Wits Appraisal for Assessing Sagittal Jaw Relationship. Int J Oral Care Res 2018;6:28–32. google scholar
15. Agarwal R, Sharma L, Soni VK, Yadav V, Soni S, & Singh K. Comparison of different angular measurements to assess sagittal Jaw discrepancy in Jaipur population-A cephalometric study. IOSR Journal of Dental and Medical Sciences 2013;10:33-36. [CrossRef] google scholar
16. Mittal A, Bohra S, Murali PS, Saidath K, Krishnanayak US. An evaluation of YEN and W angle in the assessment of anteroposterior jaw relationship. J Indian Orthod Soc 2016;50:26–30. [CrossRef] google scholar
17. Mittal D, Venkatesh S, Shivamurthy P, Mathew S. A ‘‘new vista’’ in the assessment of antero-posterior jaw relationship. APOS Trends Orthod 2015;5:151–55. [CrossRef] google scholar
18. Guinot-Barona C, Alonso Pérez-Barquero J, Galán López L, Barmak AB, Att W, Kois JC, Revilla-León M. Cephalometric analysis performance discrepancy between orthodontists and an artificial intelligence model using lateral cephalometric radiographs. J Esthet Restor Dent 2024;36:555-65. [CrossRef] google scholar
19. Greiner P, Müller B, Dibbets J. The angle between the Frankfort horizontal and the sella-nasion line. Changes in porion and orbitale position during growth. J Orofac Orthop 2004;65:217-22. [CrossRef] google scholar
20. Andredaki M, Koumantanou A, Dorotheou D, Halazonetis DJ. A cephalometric morphometric study of the sella turcica. Eur J Orthod 2007;29:449-56. [CrossRef] google scholar
21. Jena AK, Nayyer N, Sharan J, Behera BK, Marya A. Geometrical Approaches for the Accurate Identification of Normal Vertical Positions of Sella and Nasion Points in Cephalograms. Int J Dent 2022;2022:2705416. [CrossRef] google scholar
22. Yavuz İ, Durna N & Erdem A. Effects of Lingual arch application on the dento-alveolar structures in chin-cup treatment. J Dent Fac Ataturk Univ 2006;16:1-9. google scholar
23. Hussels W, Nanda RS. Analysis of factors affecting angle ANB. Am J Orthod 1984;85:411-23. [CrossRef] google scholar
24. Gor J, Kubavat A, Desai M, Mahida K, Modh A, & Vaghela A W Angle: Sagittal Jaw Dysplasia Indicator for orthodontic diagnosis outcome. JMSCR 2019;8:61-5. google scholar
25. Uslu O, Akcam MO, Evirgen S, Cebeci I. Prevalence of dental anomalies in various malocclusions. Am J Orthod Dentofacial Orthop 2009;135:328-35. [CrossRef] google scholar
26. Kotuła J, Kuc AE, Lis J, Kawala B, Sarul M. New Sagittal and Vertical Cephalometric Analysis Methods: A Systematic Review. Diagnostics (Basel) 2022;12:1723. [CrossRef] google scholar
27. Alves PV, Mazucheli J, Vogel CJ, Bolognese AM. A protocol for cranial base reference in cephalometric studies. J Craniofac Surg 2008;19:211-5. [CrossRef] google scholar
28. Axelsson S, Storhaug K, Kjaer I. Post-natal size and morphology of the sella turcica. Longitudinal cephalometric standards for Norwegians between 6 and 21 years of age. Eur J Orthod 2004;26:597-604. [CrossRef] google scholar
29. Moore JW. Variation of the sella-nasion plane and its effect on SNA and SNB. J Oral Surg 1976;34:24-6. google scholar
30. Camcı H, Salmanpour F. Cephalometric Evaluation of Anterior Cranial Base Slope in Patients with Skeletal Class I Malocclusion with Low or High SNA and SNB Angles. Turk J Orthod 2020;33:171-76. [CrossRef] google scholar
31. Hofmann E, Fimmers R, Schmid M, Hirschfelder U, Detterbeck A, Hertrich K. Landmarks of the Frankfort horizontal plane: Reliability in a three-dimensional Cartesian coordinate system. J Orofac Orthop 2016;77:373-83. [CrossRef] google scholar
32. Leitão P, Nanda RS. Relationship of natural head position to craniofacial morphology. Am J Orthod Dentofacial Orthop 2000;117:406-17. [CrossRef] google scholar
33. Macari AT, Hanna AE. Comparisons of soft tissue chin thickness in adult patients with various mandibular divergence patterns. Angle Orthod 2014;84:708-14. [CrossRef] google scholar
34. Al-Khateeb EA, Al-Khateeb SN. Anteroposterior and vertical components of class II division 1 and division 2 malocclusion. Angle Orthod 2009;79:859-66. [CrossRef] google scholar
35. Isik F, Nalbantgil D, Sayinsu K, Arun T. A comparative study of cephalometric and arch width characteristics of Class II division 1 and division 2 malocclusions. Eur J Orthod 2006;28:179-83. [CrossRef] google scholar
36. Linjawi AI, Afify AR, Baeshen HA, Birkhed D, Zawawi KH. Mandibular symphysis dimensions in different sagittal and vertical skeletal relationships. Saudi J Biol Sci 2021;28:280-85. [CrossRef] google scholar
37. Gómez Y, García-Sanz V, Zamora N, Tarazona B, Bellot-Arcís C, Langsjoen E, Paredes-Gallardo V. Associations between mandibular symphysis form and craniofacial structures. Oral Radiol 2018;34:161-71. [CrossRef] google scholar
38. Evangelista K, Silva MAGS, Normando D, Valladares-Neto J. Factors associated with the morphology of the mandibular symphysis and soft tissue chin. Dental Press J Orthod 2021;26:e2119347. [CrossRef] google scholar
39. Dandajena TC, Nanda RS. Bialveolar protrusion in a Zimbabwean sample. Am J Orthod Dentofacial Orthop 2003;123:133-7. [CrossRef] google scholar
40. Zhou X, Zheng Y, Zhang Z, Zhang Z, Wu L, Liu J, Yang W, Wang J. Customized maxillary incisor position relative to dentoskeletal and soft tissue patterns in Chinese women: A retrospective study. Korean J Orthod 2022;52:150-60. [CrossRef] google scholar
41. Swennen G, Schliephake H, Dempf R, Schierle H, Malevez C. Craniofacial distraction osteogenesis: a review of the literature: Part 1: clinical studies. Int J Oral Maxillofac Surg 2001;30:89-103. [CrossRef] google scholar
42. Daer AA, Abuaffan AH. Cephalometric norms among a sample of Yamani adults. Orthodontic Waves 2016;75:35-40. [CrossRef] google scholar
43. Agarwal S, Bhagchandani J, Mehrotra P, Kapoor S, Jaiswal RK. The SAR Angle: A Contemorary Sagital Jaw Dysplasia Marker. Orthodontic Journal of Nepal 2014;4:16-20. [CrossRef] google scholar