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 Table of Contents  
ORIGINAL ARTICLE
Year : 2021  |  Volume : 9  |  Issue : 2  |  Page : 128-135

The cephalometric norms of afro-arab population


Department of Orthodontics, Pedodontics and Preventive Dentistry, Faculty of Dentistry, University of Khartoum, Khartoum, Sudan

Date of Submission21-Oct-2021
Date of Decision29-Oct-2021
Date of Acceptance31-Oct-2021
Date of Web Publication17-Dec-2021

Correspondence Address:
Prof. Amal Hussein Abuaffan
Department of Orthodontics, Pedodontics and Preventive Dentistry, Faculty of Dentistry, University of Khartoum, Khartoum
Sudan
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jhnps.jhnps_64_21

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  Abstract 


Objectives: We aimed to determine the skeletal and dental cephalometric norms for Sudanese adults. Materials and Methods: A total of 106 lateral cephalograms (51 males and 55 females) aged 18–25 years with Class I occlusion and well-balanced profile were enrolled in this study. Twenty-seven variables were analyzed digitally by VistaDent software according to the McNamara, Tweed, and Jarabak analysis. Results: A statistically significant difference between genders was found in the skeletal variables (sella-nasion-B point angle, A point-nasion-B point angle, facial plane angle, Y-axis, mandibular to anterior cranial base angle, mandibular to Frankfort horizontal plane angle, mandibular to maxillary plane angle, anterior cranial base length, posterior facial height, anterior facial height, lower anterior facial height, effective maxillary length, effective mandibular length, and maxilla-mandibular difference) and dental variables (maxillary incisor to anterior cranial base angle, mandibular incisor to Frankfort horizontal plane angle, and lower incisor edge to A point-pogonion line distance). Skeletally, Sudanese males had more prognathic maxilla and more prominent chin. The males had longer midfacial lengths and mandibular lengths. Sudanese adults had a tendency toward bimaxillary protrusion with slight dental proclination than Arab, and less protrusion compared with African or African American populations. Conclusion: The results give a better insight for proper diagnosis and treatment planning for Sudanese orthodontic and orthognathic patients.

Keywords: Afro-Arab, cephalometric, Sudanese


How to cite this article:
Younso MA, Abuaffan AH. The cephalometric norms of afro-arab population. J Head Neck Physicians Surg 2021;9:128-35

How to cite this URL:
Younso MA, Abuaffan AH. The cephalometric norms of afro-arab population. J Head Neck Physicians Surg [serial online] 2021 [cited 2022 Jan 18];9:128-35. Available from: https://www.jhnps.org/text.asp?2021/9/2/128/332728




  Introduction Top


Cephalometric norms provide a useful guidance in diagnosis and treatment planning. However, they are subject to variability in morphological characteristics of different racial and ethnic groups. Hence, norms that are conventional for one population are not necessarily applicable for others.[1] Early in 1922, Pacini introduced the first method in cephalometric that measured the growth and development of the face.[2] Later, Broadbent published a method that utilized standardized head radiographs in the living heads rather than skulls.[3] Originally, the cephalometric analysis had been developed as a technology largely in the United States and Europe. Therefore, the Caucasian normative databases are widely used as a reference to characterize craniofacial morphology among other populations.[4]

Worldwide, numerous cephalometric norms in Arabian,[5],[6],[7],[8],[9],[10],[11],[12],[13],[14],[15],[16],[17] Asian,[18],[19],[20] African,[21],[22],[23],[24],[25] African-American,[26],[27],[29],[30],[31],[32],[33] and European[34] countries showed a variety of cephalometric values among different ethnic groups, age, and gender.

In the recent decade, the demand for orthodontic treatment has been increased within the Sudanese population. However, a limited cephalometric study was available. The current study aims to establish the essential angular and linear Cephalometric measurements creating a proper insight for a better diagnosis and treatment planning, in addition, to be contributed in teaching and research.


  Materials and Methods Top


A cross-sectional descriptive analytical study was carried out in the Medical Campus University of Khartoum. A total of 106 students, 51 males and 55 females (mean age, 20.63 ± 2.03 years), were selected according to the inclusion criteria: no previous or active orthodontic treatment, well-balanced face, Class I occlusion, normal overbite and overjet, no facial deformity, and none or minor incisor irregularity.

The ethical approval was attained from the Ethics Research Committee, Faculty of Medicine, University of Khartoum.

The aim of the study was explained to all students in the lecture rooms, laboratories, and dental clinics. An initial visual examination was carried out and the selected students were requested to undergo a further examination at the dental clinic. The individuals who fulfilled the inclusion criteria were asked to participate and those who agreed signed a consent form and registered with full name, age, and mobile number.

Subsequently, the participants were called and transported to the radiology center. The student was seated in the radiographic unit (Scanning Planmeca ProMax® cephalostat), wearing a lead apron. Their teeth were in centric occlusion and their lips were in repose. The digital cephalograms were taken by a trained operator, saved in JPG format, and copied to a CD-ROM. Each digital lateral cephalogram was identified by serial code, age, and gender and then loaded to the software program (VistaDent OC™ - Version 4.2.61 (177) ©2006 – GAC International, Inc.).[35]

A custom analysis, including 14 angular and 12 linear cephalometric measurements and 1 proportion [Table 1], was appeared directly on the window. Finally, the results were printed out on A4 papers and used for statistical analysis using SPSS (IBM) software program Version 23.
Table 1: Angular and linear measurements used in this study

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The skeletal and dental cephalometric reference points are demonstrated in [Figure 1], and the reference lines are illustrated in [Figure 2].
Figure 1: The cephalometric landmarks: A, Point A; ANS, anterior nasal spine; B, Point B; Ba, basion; Cond, condylion; Gn, gnathion; Go, gonion; ii, L1 incision inferius; iia, incision inferius apicalis; is, incision superius; isa, incision superius apicalis; Li, labrale inferius; Ls, labrale superius; Me, menton; N, nasion; Ns, pronasale; Or, orbitale; P, porion; PNS, posterior nasal spine; Pg, pogonion; Pg', pogonion soft tissue; Ptm, pterygomaxillary fissure; S, sella turcica; Sn, subnasale; U1, maxillary central incisor

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Figure 2: Cephalometric reference lines: (1) SN plane, (2) Frankfort horizontal plane (FH), (3) Maxillary plane (PP), (4) Occlusal plane, (5) Mandibular plane (MP), (6) Nasion-perpendicular, (7) A-vertical, (8) Max 1, (9) Mand1, (10) A-Pog, (11) E-line

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Reliability of the measurements

Twenty-six radiographs were selected randomly and retraced by the same researcher after 4 weeks. Dahlberg's formula and a paired t-test were applied. The differences between the two readings were statistically insignificant in all measurements [Table 2], P < 0.05 significant.
Table 2: Dahlberg and paired sample t-test

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  Results Top


In [Table 3], gender dimorphism was found to be statistically significant for the majority of the angular variables. Skeletally, angular variables (ANB, SN-MP, FH-MP, PP-MP, and NSG) were significantly greater in females. SNB and SNPg were significantly greater in males. There was no significant difference between genders in SNA and facial axis.
Table 3: Results of total and comparison between Sudanese males and females using t-test

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Dentally, males showed a greater significant difference in Max 1-SN and FMIA than females. There was no significant difference between genders in Max 1-PP, II, and IMPA.

All skeletal linear measurements revealed a greater statistically significant difference in males. Genders revealed no significant difference for Pn-A and Pn-Pg. Dentally, females exhibited a greater significant difference in L1-APg than males. Although, there was no significant difference in U1-Avert and Wits measurements.


  Discussion Top


These days, the number of Sudanese patients seeking orthodontic treatment has increased, increasing the demand for more accurate values of cephalometric measurements. Improving the diagnosis and treatment planning for both orthodontic and orthognathic surgery patients.

It is well known that Sudan is the third-largest country in Africa, bordered by many Arabian and African countries. The current study aimed to reflect the multiethnicity of participants who are Sudanese by nationality and to estimate the cephalometric features of Sudanese adults with normal occlusion, well-balanced faces, and mean age of 20.6 years.

The results of the current study showed a significant difference in the majority of the cephalometric variables.

The sagittal relationship of both jaws to the cranial base in Sudanese sample showed a gender dimorphism except SNA angle. However, SNA angle value showed a slight increase compared with Arabian countries,[4],[7],[10],[12],[14],[15],[16],[17] European,[34] and Asian.[18],[19] In contrast, it recorded less value than African,[21],[22],[23],[24],[25] African American,[26] and Afro-Caucasian Brazilian[32] populations.

In conclusion, Sudanese exhibited more maxillary protrusion than Arabs and less than African and Black American. This variation may reflect the racial background of Sudanese population.

SNB angle results showed a significant difference (P < 0.01), with males having more value. Moreover, both genders recorded more prognathic mandible in comparison with Arabian populations.[5],[7],[10],[12],[14],[15],[17] In contrast, the Cameroonian[21] and Zimbabwean[25] populations showed a higher value of SNB angle than Sudanese population.

ANB angle reported a gender dimorphism (P < 0.05), with Sudanese females showing a higher value. Compared with other populations,[5],[15],[20],[22],[25],[26] it was less, and higher than Turkish. Therefore, it can be concluded that the Sudanese population are characterized by skeletal type I relationship.

SNPg angle revealed a significant difference (P < 0.001), with the males having more mean value. In this study, males have more prominent chin compared with the Egyptian,[5] Libyan,[10] and Yemeni males.[17] Whereas, Sudanese females were in agreement with Egyptian[5] and Yemeni females.[17]

The vertical inclination of the mandibular plane in relation to maxillary, Frankfort horizontal, and anterior cranial base planes showed a highly significant difference between Sudanese genders (P < 0.001). The males have more anterior inclination of SN-MP than females. Both genders showed less mean value than Black American[29] and Filipino.[20] The Sudanese female showed more posterior inclination of the mandible compared with Egyptian,[20] Saudi,[15] Libyan,[10] and Turkish[19] while male has a more anterior inclination in comparison with the former countries. The vertical inclination of the SN-MP in Sudanese female was showed a clockwise direction of rotation.

The mean value of FH-MP angle in Sudanese females showed a higher value than males; both genders showed more value compared with Kuwaiti[8] and Zimbabwean[25] and less value when compared with Egyptian,[5] Saudi,[15] Kenyan,[22] and Black American.[30]

Sudanese females have a more divergent angle between maxillary and mandibular planes. The mean value of PP-MP angle for males was higher than Yemen[17] and less than Emirati[4] and Jordanian males.[7] On the other hand, Sudanese females showed higher values than former countries. The increased value of PP-MP angle among Sudanese females indicated a steeper mandible.

SNGn angle (Y-axis) showed a more significant difference in females (P < 0.001), which specified that Sudanese females have slightly posterior position of the mandible with a slight vertical growth compared to males. Concerning gender, the mean values were in agreement with the Egyptian[5] higher from Libyan.[10] Whereas, the Emirati[4] and Saudi[15] genders showed greater mean value than Sudanese counterparts.

Facial axis angle recorded no significant difference between Sudanese genders, and it was more than Mexican American[33] and Turkish.[19] While Sudanese males value are in accordance with Syrian[16] and Cameroonian males.[21]

In Sudanese, the facial angle was 90.3 ± 4.1, which indicated average vertical development.[36]

The mean value of Max 1-SN angle revealed a gender dimorphism (P < 0.01), with males having more proclined upper incisors. Whereas, gender had a higher mean value than Turkish,[19] Mexican American,[33] and Arab countries.[10],[11],[14],[15] However, Sudanese males are in accordance with Zimbabwean.[25]

Max 1-PP angle for Sudanese gender revealed no significant difference. The relation of the upper incisors to the maxillary plane in Sudanese subjects was similar or slightly proclined than Arabs[7],[11] and less in comparison to to African-American.[28]

In the current study, no significant difference between genders in relation to the interincisal angle was recorded. It was similar to Saudi[15] and closely to Emirati results.[4]

Sudanese had slight bimaxillary proclination compared to Arabs[5],[7],[8],[10],[12],[14],[17] and less than Africans.[22],[23],[25]

The mean value of the mandibular incisor to the mandibular plane angle revealed no significant difference between the Sudanese genders. It was near to the African-American, less than Zimbabwean,[25] more than Arab,[5],[7],[8],[10],[11],[13] European,[34] and Asian populations.[20]

The Frankfort to mandibular incisor angle for Sudanese genders revealed a significant difference (P < 0.001). Males showed a higher mean value, which indicated that females showed more proclination of the lower incisors than males and Sudanese results were more than African-American[27] and less than Kuwaiti.[8]

All the skeletal linear measurements in the current study revealed a highly significant difference between Sudanese genders (P < 0.001), with the males having the greater values except for Pn-A and Pn-Pg, which showed no significant difference.

The mean value for the anterior cranial base S-N in the present study was in agreement with the Egyptian,[5] South African,[24] and African-Brazilian.[31] Whereas, it was shorter than the Libyan,[10] Filipino.[20] Icelandic,[34] Cameroonian,[21] and African-American populations.[30]

The mean value of the posterior facial height S-Go in Sudanese sample was shorter compared with Emirati[6] and Black American.[28] In contrast, it was longer than the Afro-Caucasian Brazilian.[32] Moreover, females showed shorter posterior facial height compared with the Egyptian[5] and African-Brazilian.[31]

The total anterior facial height N-Me of Sudanese sample was less compared with the Emirati,[6] African-American,[30] and Filipino[20] and more than the Afro-Caucasian Brazilian.[32] Whereas, the lower anterior facial height ANS-Me in Sudanese sample was longer than Saudi[15] and Syrian[16] cohort but shorter than Emirati,[6] Kuwaiti,[8] Turkish,[18] Filipino,[20] African-American,[30] and Mexican American.[33]

The effective maxillary length Cond-A and effective mandibular length Cond-Gn for Sudanese sample was higher than the mean value for Kuwaiti[9] and lower than the Emirati,[6] Turkish,[18] African- American,[30] and Mexican American.[33]

The maxillary to mandibular length mean value difference in Sudanese sample was higher than the reported mean value from the Kuwaiti[9] and Syrian.[16] However, it was less than African-American[30] and Turkish.[18]

In the present study, only linear distance of Pn-A and Pn-Pg revealed no statistically significant difference between Sudanese genders. The anteroposterior position of the maxilla and mandible in relation to the nasion perpendicular in Sudanese sample showed more protrusion in comparison with Syrian[16] and Turkish.[19] Although, it was less than Kuwaiti.[8]

The attained results indicated that the Sudanese have more protrusive maxilla, mandible, and chin position in relation to the nasion perpendicular line.

The position of the maxillary incisor relative to underlying basal bone U1-Avert showed no gender dimorphism. The presented results showed that Sudanese sample had slightly protrusive maxillary incisors with slight maxillary protrusion than the Syrian[16] and Turkish.[18] In contrast, Sudanese shared the same maxillary incisor protrusion with Mexican American population.[33]

The anteroposterior position of the mandibular incisor in relation to the A-Pg line had a significant difference between Sudanese genders (P < 0.05), with males showing less value. Sudanese genders showed protrusive lower incisor more than Arabs[7],[8],[10],[11],[13],[16] and less than African-[21],[25] and African-American.[30]

The mean value of Wits appraisal measurement in Sudanese adults showed no significant difference. It had higher values compared with Cameroonians[21] and lower values than Egyptian,[5] Kuwaiti,[9] Zimbabwean,[25] South African,[24] and Black American.[30]

The present study showed a highly significant gender difference in the proportion of the posterior to anterior facial heights (P < 0.001). Males had an increased Jarabak ratio than females. In addition, the males showed a higher or nearly the same mean value to the Egyptian,[5] Libyan,[10] African-American,[28] and African-Brazilian sample.[31]


  Conclusion Top


  • The sagittal relationships of the maxilla and mandible in relation to the anterior cranial base in a Sudanese sample showed slight protrusion when compared with Arabs and less with African population
  • The relative position of the maxilla to the mandible in the sagittal and vertical direction was a skeletally Class I relationship with normal vertical development
  • The Sudanese males showed more anterior inclination of the mandibular plane and protruded chin than females
  • Sudanese females showed a steeper mandible in relation to maxilla than males and a slightly posterior position of the mandible with vertical growing compared to males
  • Sudanese had slight bimaxillary proclination of incisors when compared with Arabs and less proclination compared with Africans
  • Sudanese males showed more proclination of maxillary incisors than females, while Sudanese females showed more proclination of the lower incisors
  • Most of the skeletal linear measurements in the Sudanese males showed larger dimensions than females.


Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Disclosure

This material has never been published and is not currently under evaluation in any other peer-reviewed publication.

Ethical approval

The permission was taken from Institutional Ethics Committee prior to starting the project. All procedures performed in studies involving human participants were in accordance with the ethical standards of the Institutional and/or National Research Committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

Acknowledgments

An appreciation and thanks to my colleagues at the University of Khartoum and the staff at the department of orthodontics for their continual support. A special thanks to Dr. Adeeb Hayyan for his support and patience for reading and giving useful and scientific notes.



 
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    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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