Indian Journal of Dental ResearchIndian Journal of Dental ResearchIndian Journal of Dental Research
HOME | ABOUT US | EDITORIAL BOARD | AHEAD OF PRINT | CURRENT ISSUE | ARCHIVES | INSTRUCTIONS | SUBSCRIBE | ADVERTISE | CONTACT
Indian Journal of Dental Research   Login   |  Users online: 68

Home Bookmark this page Print this page Email this page Small font sizeDefault font size Increase font size         

 


 
ORIGINAL RESEARCH Table of Contents   
Year : 2009  |  Volume : 20  |  Issue : 2  |  Page : 150-152
Radiographic evaluation of the mental foramen in a selected Iranian population


1 Department of Oral and Maxillofacial Radiology, Dental Faculty, Babol University of Medical Sciences, Babol, Iran
2 Private Practice, Babol, Iran

Click here for correspondence address and email

Date of Submission24-Jul-2007
Date of Decision04-Oct-2007
Date of Acceptance21-Nov-2007
Date of Web Publication23-Jun-2009
 

   Abstract 

Background: Information on the position of the mental foramen is important for dental surgeons. Variations in its position can be a cause of complications during local anesthesia or surgical procedures. The usual position of the mental foramen in an Iranian population has not been previously reported.
Aims: The purpose of this study was to determine the most common location of the mental foramen in an Iranian population. We also analyzed gender differences and the symmetry of location within individuals.
Materials and Methods : 400 panoramic radiographs were evaluated with regard to the location and symmetry of the mental foramina in male and female subjects.
Results : We found that the mental foramen was located between the first and second premolars in 47.2% of patients and in line with the second premolar in 46%. In 49.2% of males, the mental foramen was in line with the second premolar. In 50.9% of females it was between the first and second premolars. It was symmetrical in 85.7%.
Conclusions : Based on this study it appears that the most common position of mental foramen is either between the two premolars or in line with the second premolar. This is in concordance with previous studies.

Keywords: Mandible, mental foramen, mental nerve, panoramic, radiography

How to cite this article:
Haghanifar S, Rokouei M. Radiographic evaluation of the mental foramen in a selected Iranian population. Indian J Dent Res 2009;20:150-2

How to cite this URL:
Haghanifar S, Rokouei M. Radiographic evaluation of the mental foramen in a selected Iranian population. Indian J Dent Res [serial online] 2009 [cited 2014 Oct 31];20:150-2. Available from: http://www.ijdr.in/text.asp?2009/20/2/150/52886
The mental foramen on each side is located on the buccal cortex of the mandibular bone and lies near the apices of the premolars. It has been shown to be located at precisely the same level on most humans (13-15 mm superior to the inferior border of the mandible). The opening of the mental foramen is directed outward, upward, and posteriorly, viewed from inside out. It transmits the mental vessels and nerve. [1] The mental nerve is a terminal branch of the inferior alveolar nerve; it supplies sensory innervation to the lower lip, the buccal vestibule, and the gingiva mesial to the first mandibular molar. [2] The mental bundle can be traumatized during surgical procedures, resulting in paresthesia or anesthesia in the area innervated by the nerve. Additionally, local anesthesia of the terminal incisive branches of the inferior alveolar nerve and the mental nerve can be achieved if the mental canal is accurately located and anesthetic solution deposited within it. Thus, accurate information regarding the location and orientation of the mental canal and its foramen can be very important. [3]

As the bone density increases, the mental foramen becomes more difficult to identify on radiographs. [4] Such cases, in which the mental foramen cannot be identified on panoramic radiographs under ordinary exposure and viewing conditions, were classified as 'unidentified type' by Yosue and Brooks. [5],[6]

The location of mental foramen has been studied in different populations. [2],[3],[4],[5],[6],[7],[8],[9],[10],[11],[12],[13],[14] The purpose of this study was to report the usual position of the mental foramen in Iranians; it has not been reported in this population before.


   Materials and Methods Top


We evaluated 400 panoramic radiographs of patients who had been referred to our Dentomaxillofacial Radiology Center in Babol city (in Iran) during two years. All panoramic radiographs were taken by Planmeca 2002EC (tube potential: 60-80 KV, tube current: 4-12 mA, total filtration: 2.5 mmAl, focal spot: 0.3, and time: 18 s) and had high-quality processing. Exclusion criteria were:

  1. Presence of a radiolucent lesion in the lower jaw anywhere in the area extending from the right first molar to the left first molar
  2. Presence of a missing tooth in the lower jaw (between 36 and 46)
  3. Nonvisualization of the mental foramen bilaterally
  4. Incomplete eruption of permanent teeth
  5. Patient under 18 years
  6. Presence of periodontal lesions
  7. Patient with previous orthodontic treatment
  8. Presence of crowding and spacing in the lower arch
The position of the image of the mental foramen was recorded as follows:

Position 1: Situated anterior to the first premolar

Position 2: In line with the first premolar

Position 3: Between the first and second premolars

Position 4: In line with the second premolar

Position 5: Between the second premolar and first molar

Position 6: In line with the first molar

We used the edge of a ruler to identify the longitudinal axis of the nearest tooth and the position of the mental foramen was recorded in relation to this. If the mental foramen was too large or was situated between two teeth, the position of the foramen was established after drawing an imaginary line parallel to the long axis of the teeth. [4] After evaluation of each panoramic radiograph, the location of the mental foramen on each side was recorded in the form. The location of the mental foramen was reported on the basis of gender and symmetry or asymmetry.


   Results Top


Of the 400 panoramic radiographs analyzed, 178 were that of males and 222 that of females. The most common position for the mental foramen in this sample was position 3 (47.2%). There was no case found in position 1 (anterior to the first premolar). On the right side, the commonest position of the mental foramen was position 3 (24.7%) and on the left side it was position 4 (23.6%) [Table 1]. Position 4 was the most common one among males (49.2%) and position 3 was the most common one among females (50.9%) [Table 2].

In 343 cases (85.7%) the mental foramina were symmetrically located. For the symmetrically placed mental foramina, the most common location was position 3 (41.5%), followed by position 4 (39.8%). No case was found in position 1 and 6. No statistically significant differences were seen between males and females in symmetry and asymmetry location of mental foramen in both sides. P < 0.05 was taken to indicate statistical significance [Table 3].


   Discussion Top


There is considerable debate regarding the normal position of the mental foramen in different populations. In our series of 400 panoramic radiographs the location of the mental foramen varied widely, being found at any position between the root of the first premolar and the roots of the first molar; this is in accordance with previous studies. According to this study, in 47.2% of the cases the mental foramen was located between the first and second premolars and in 46% it was in line with the second premolar; thus these two positions accounted for 93.2% of the cases.

Studies done by Moiseiwtsch [2] in a North American white population and by Fishel et al. [7] and Olasoji et al. [8] in Northern Nigerian adults showed that the most common location of the mental foramen was between the two premolars. These findings are consistent with our results. But studies done in other populations such as Malays, Asian Indians, Kenyan Africans, and Saudis, as well as the studies done by Phillips et al., have indicated that the mental foramen is most commonly positioned in line with the second premolar tooth. [3],[4],[9],[10],[11],[12],[13],[14]

In our review of literature we found that according to most authors the mental foramen is usually located between the lower premolars. [15],[16],[17] However, there were some studies that reported that it most commonly lies near the apex of the second premolar. [1],[18],[19],[20] Other studies have found that both locations are common. [21],[22]

In this study we used panoramic radiographs because the mental foramen is seen more consistently on the wide field of mandible view in panoramic radiographs than on periapical radiographs. [6]

We selected patients over the age of 18 because we needed patients with completed skeletal growth. The presence of periodontal lesions and also previous orthodontic treatment could cause tooth migration; we, therefore, omitted these cases from our study.

In conclusion, the most common locations of the mental foramen are between the two premolars and in line with the second premolar (below and/or mesial to the second premolar). This agrees with the results of previous studies in other populations. The mental foramina are usually symmetrically located on both sides.

 
   References Top

1.Woelfel JB, Scheid RC. Structures that form the foundation for tooth function. Dental Anatomy: Its relevance to dentistry. 6 th ed. Newyork: Lippincott, Williams and Wilkins: 2002. p. 19.  Back to cited text no. 1    
2.Moiseiwtsch JR. Position of the mental foramen in a North American,white population. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998;85:457-60.  Back to cited text no. 2    
3.Phillips JL,Weller RN, Kulild JC. The mental foramen: Part1. Size,orientation and positional relationship to the mandibular second premolar. J Endod 1990;16:221-3.  Back to cited text no. 3    
4.Ngeow WC, Yuzawati Y. The location of the mental foramen in a selected Malay population. J Oral Sci 2003;45 : 171-5.  Back to cited text no. 4    
5.Yosue T, Brooks SL. The appearance of mental foramina on panoramic radiographs. I.Evaluation of patients. Oral Surg Oral Med Oral Pathol 1989;68:360-4.  Back to cited text no. 5    
6.Yosue T, Brooks SL. The appearance of mental foramina on panoramic and periapical radiographs. II.Experimental evaluation. Oral Surg Oral Med Oral Pathol 1989;68:488-92.  Back to cited text no. 6    
7.Fishel D, Buchner A, Hershkowith A, Kaffe I. Roentgenologic study of the mental foramen. Oral Surg Oral Med Oral Pathol 1976;41:682-6.  Back to cited text no. 7    
8.Olasoji HO, Tahir A, Ekanem AU, Abubakar AA. Radiographic and anatomic locations of mental foramen in northern Nigerian adults. Niger Postgard Med J 2004;11:230-3.  Back to cited text no. 8    
9.Shankland WE 2nd. The position of the mental foramen in Asian Indians. J Oral Implantol 1994;20:118-23.  Back to cited text no. 9    
10.Mwaniki DL, Hassanali J. The position of mandibular and mental foramina in Kenyan African mandibles. East Afr Med J 1992;69:210-3.  Back to cited text no. 10    
11.Al Jasser NM, Nwoku AL. Radiographic study of the mental foramen in Saudi females. Saudi Med J 1996;17:471-4.  Back to cited text no. 11    
12.Al Jasser NM, Nwoku AL. Radiographic study of the mental foramen in a selected Saudi population. Dentomaxillofac Radiol 1998;27: 341-3.  Back to cited text no. 12    
13.Phillips JL, Weller RN, Kulild JC. The mental foramen: Part 2. Radiographic position in relation to the mandibular second premolar. J Endod 1992;18:271-4.  Back to cited text no. 13    
14.Phillips JL, Weller RN, Kulild JC. The mental foramen: Part 3.Size and position on panoramic radiographs. J Endod 1992;18:383-6.  Back to cited text no. 14    
15.Atkinson ME, White FH. The skeletal system. Principles of Anatomy and Oral Anatomy for Dental Students. 1 st ed. Edinburgh: Churchill Livingstone; 1992. p. 120.  Back to cited text no. 15    
16.Robinson PD, Pitt ford TR, McDonald F. Mandibular anaesthesia. Local anaesthesia in Dentistry. 1 st ed. Oxford: Wright; 2000. p. 52.  Back to cited text no. 16    
17.Hiatte JL, Gartner LP.Anatomic basis for local anesthesia. Textbook of Head and Neck Anatomy. 3 rd ed. Newyork: Lippincott,Williams and Wilkins; 2001.p. 296.  Back to cited text no. 17    
18.White SC, Pharoah MJ.Normal radiographic anatomy. Oral Radiology: Principles and interpretation. 5 th ed. St Louis: Mosby; 2004. p. 183.  Back to cited text no. 18    
19.Liebgott B. The skull. The Anatomical Basis of Dentistry. 2 nd ed. St Louis: Mosby; 2001. p. 189.  Back to cited text no. 19    
20.Berkovitz BKB, Holland GR, Moxham BJ. Dento-osseous structures. Oral Anatomy,Histology and Embryology. 3 rd ed. London: Mosby; 2002. p. 11.  Back to cited text no. 20    
21.Williams PL, Warwich R, Dyson M. Osteology. Gray's Anatomy.37 th ed.Edinburgh: Churchill Livingstone; 1989.p. 368.  Back to cited text no. 21    
22.Malamed SF. Techniques of mandibular anesthesia. Handbook of local anesthesia. 5 th ed. St Louis: Mosby; 2004:246-8.  Back to cited text no. 22    

Top
Correspondence Address:
Sina Haghanifar
Department of Oral and Maxillofacial Radiology, Dental Faculty, Babol University of Medical Sciences, Babol
Iran
Login to access the Email id


DOI: 10.4103/0970-9290.52886

PMID: 19553713

Get Permissions




 
 
    Tables

  [Table 1], [Table 2], [Table 3]

This article has been cited by
1 Determination of the Location of the Mental Foramen: A Critical Review
Anita Aminoshariae,Anne Su,James C. Kulild
Journal of Endodontics. 2014;
[Pubmed]
2 Position of the mental foramen in a Moroccan population: A radiographic study
Ahmed Chkoura,Wafaa El Wady
Imaging Science in Dentistry. 2013; 43(2): 71
[Pubmed]
3 Topography of the mental foramen in human skulls originating from different time periods
A. Gawlikowska-Sroka,L. Stocki,P. Dabrowski,B. Kwiatkowska,J. Szczurowski,F. Czerwinski
HOMO - Journal of Comparative Human Biology. 2013; 64(4): 286
[Pubmed]
4 Accessory mental foramina: prevalence, position and diameter assessed by cone-beam computed tomography and digital panoramic radiographs
Thaís Sumie Nozu Imada,Luciana Maria Paes da Silva Ramos Fernandes,Bruna Stuchi Centurion,Christiano de Oliveira-Santos,Heitor Marques Honório,Izabel Regina Fischer Rubira-Bullen
Clinical Oral Implants Research. 2012; : n/a
[Pubmed]
5 Study of the inferior alveolar canal and mental foramen on digital panoramic images
Pria, C.M. and Masood, F. and Beckerley, J.M. and Carson, R.E.
Journal of Contemporary Dental Practice. 2011; 12(4): 265-271
[Pubmed]
6 Accessory mental foramen: A rare anatomical finding
Thakur, G. and Thomas, S. and Thayil, S.C. and Nair, P.P.
BMJ Case Reports. 2011;
[Pubmed]
7 Evaluation of the mental foramen and accessory mental foramen in Turkish patients using cone-beam computed tomography images reconstructed from a volumetric rendering program
A. Kalender, K. Orhan, U. Aksoy
Clinical Anatomy. 2011; : n/a
[VIEW]
8 Morphometrical and morphological study of mental foramen in dry dentulous mandibles of South Andhra population of India
Sankar, D.K., Bhanu, S.P., Susan, P.J.
Indian Journal of Dental Research. 2011; 22(4): 542-546
[Pubmed]
9 Absence and hypoplasia of the mental foramen detected in CBCT images: a case report
Luciana Maria Paes Silva Ramos Fernandes, Ana Lúcia Álvares Capelozza, Izabel Regina Fischer Rubira-Bullen
Surgical and Radiologic Anatomy. 2011;
[VIEW]
10 Accessory mental nerve: case report, review and its role in trigeminal neuralgia
Anjani Kumar Jha, N. Girish Kumar
Surgical and Radiologic Anatomy. 2011;
[VIEW]
11 A Variation in the Position of the Mental Foramen: A Case Report
Sonal Shah, Suhas Vaze, Kriti Kinhal
Journal of Maxillofacial and Oral Surgery. 2010; 9(3): 307
[VIEW]
12 Mental foramen / canal / and mental block anesthesia
Almudares, M.F. and Al-Seghairi, M.M.
Journal of International Dental and Medical Research. 2009; 2(2): 37-39
[Pubmed]



 

Top
 
 
  Search
 
 
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Email Alert *
    Add to My List *
* Registration required (free)  
 


    Abstract
    Materials and Me...
    Results
    Discussion
    References
    Article Tables

 Article Access Statistics
    Viewed4811    
    Printed134    
    Emailed6    
    PDF Downloaded1328    
    Comments [Add]    
    Cited by others 12    

Recommend this journal