Original Article

CBCT evaluation of anterior loop length and mental foramen position in Vietnamese Population (CBCT Evaluation of Anterior Loop Length)

Quang H. Nguyen, Phimatra J. Putra, Hieu Nguyen, Hai-Van Giap, Florenly Florenly

Quang H. Nguyen
Faculty of Dentistry, Universitas Prima Indonesia, Medan, Indonesia

Phimatra J. Putra
Department of Oral Maxillofacial Radiology, Universitas Prima Indonesia, Medan, Indonesia

Hieu Nguyen
Private Clinic, Hanoi, Vietnam

Hai-Van Giap
Private Clinic, Hanoi, Vietnam

Florenly Florenly
Department of Oral Biology, Faculty of Dentistry, Universitas Prima Indonesia, Medan, Indonesia. Email: ly@unprimdn.ac.id
Online First: August 01, 2021 | Cite this Article
Nguyen, Q., Putra, P., Nguyen, H., Giap, H., Florenly, F. 2021. CBCT evaluation of anterior loop length and mental foramen position in Vietnamese Population (CBCT Evaluation of Anterior Loop Length). Journal of Dentomaxillofacial Science 6(2): 75-79. DOI:10.15562/jdmfs.v6i2.1173

Objective: The purpose of this study was to evaluate the prevalence and length of anterior loop, and determine the accurate position of the mental foramen in Vietnamese population.

Material and Methods: One hundred and twelve CBCT scans taken within July 2017 until February 2020 were used in this study. All images were evaluated using OsiriX DICOM Viewer. The loop length on both side of the mandible was assessed using oblique transverse method by one examiner based on a standardized procedure. The data collected were analyzed using SPSS ver.26.0..

Results: The prevalence of the loop was 92.9% of the sample. The mean of anterior loop length was 1.72 ± 1.00mm. There was no significant difference between genders or sides of the mandible. The most common position of the mental foramen was in line with the axis of the second premolar and below the apices of the premolars.

Conclusion: Cautions should be taken when placing implant in proximity to the mental foramen as anterior loop is present in most of the case. Based on this study, it is considered safer to place implant 5mm anterior to the mental foramen for Vietnamese population


Tolstunov L. Implant zones of the jaws: implant location

and related success rate. J Oral Implantol 2007;33: 211-220.

Phillips JL, Weller RN, Kulild JC. The mental foramen: 1.

Size, orientation, and positional relationship to the mandibular second premolar. J Endod 1990;16: 221-223.

Apostolakis D, Brown JE. The anterior loop of the inferior

alveolar nerve: prevalence, measurement of its length and

a recommendation for interforaminal implant installation

based on cone beam CT imaging. Clin Oral Implants Res

;23: 1022-1030.

Kieser J, Kuzmanovic D, Payne A, et al. Patterns of emergence of the human mental nerve. Arch Oral Biol 2002;47:


Shaban B, Khajavi A, Khaki N, et al. Assessment of the

anterior loop of the inferior alveolar nerve via cone-beam

computed tomography. J Korean Assoc Oral Maxillofac

Surg 2017;43: 395-400.

Velasco-Torres M, Padial-Molina M, Avila-Ortiz G, et al.

Inferior alveolar nerve trajectory, mental foramen location

and incidence of mental nerve anterior loop. Med Oral

Patol Oral Cir Bucal 2017;22: e630-e635.

Al-Mahalawy H, Al-Aithan H, Al-Kari B, et al.

Determination of the position of mental foramen and frequency of anterior loop in Saudi population. A retrospective CBCT study. Saudi Dent J 2017;29: 29-35.

Kutuk N, Demirbas AE, Gonen ZB, et al. Anterior mandibular zone safe for implants. J Craniofac Surg 2013;24:


Mardinger O, Chaushu G, Arensburg B, et al. Anterior

loop of the mental canal: an anatomical-radiologic study.

Implant Dent 2000;9: 120-125.

de-Brito AC, Nejaim Y, de Freitas DQ, et al. Panoramic

radiographs underestimate extensions of the anterior loop

and mandibular incisive canal. Imaging Sci Dent 2016;46:


Bou-Serhal C, Jacobs R, Flygare L, et al. Perioperative

validation of localisation of the mental foramen.

Dentomaxillofac Radiol 2002;31: 39-43.

Lu CI, Won J, Al-Ardah A, et al. Assessment of the anterior

loop of the mental nerve using cone beam computerized

tomography scan. J Oral Implantol 2015;41: 632-639.

Neiva RF, Gapski R, Wang HL. Morphometric analysis of

implant-related anatomy in Caucasian skulls. J Periodontol

;75: 1061-1067.

Wong SK, Patil PG. Measuring anterior loop length of the

inferior alveolar nerve to estimate safe zone in implant

planning: A CBCT study in a Malaysian population. J

Prosthet Dent 2018;120: 210-213.

Jacobs R, Mraiwa N, vanSteenberghe D, et al. Appearance,

location, course, and morphology of the mandibular incisive canal: an assessment on spiral CT scan.

Dentomaxillofac Radiol 2002;31: 322-327.

Prados-Frutos JC, Salinas-Goodier C, Manchon A, et al.

Anterior loop of the mental nerve, mental foramen and

incisive nerve emergency: tridimensional assessment and

surgical applications. Surg Radiol Anat 2017;39: 169-175.

Uchida Y, Yamashita Y, Goto M, et al. Measurement of

anterior loop length for the mandibular canal and diameter of the mandibular incisive canal to avoid nerve damage

when installing endosseous implants in the interforaminal

region. J Oral Maxillofac Surg 2007;65: 1772-1779.

Misch CE, Crawford EA. Predictable mandibular nerve

location-a clinical zone of safety. Int J Oral Implantol

;7: 37-40.

Kaya Y, Sencimen M, Sahin S, et al. Retrospective radiographic evaluation of the anterior loop of the mental nerve:

comparison between panoramic radiography and spiral

computerized tomography. Int J Oral Maxillofac Implants

;23: 919-925.

Bavitz JB, Harn SD, Hansen CA, et al. An anatomical study

of mental neurovascular bundle-implant relationships. Int

J Oral Maxillofac Implants 1993;8: 563-567.

Kuzmanovic DV, Payne AG, Kieser JA, et al. Anterior loop

of the mental nerve: a morphological and radiographic

study. Clin Oral Implants Res 2003;14: 464-471.

Parnami P, Gupta D, Arora V, et al. Assessment of the horizontal and vertical position of mental foramen in indian

population in terms of age and sex in dentate subjects

by pano-ramic radiographs: A retrospective study with

review of literature. Open Dent J 2015;9: 297-302.

Alam MK, Alhabib S, Alzarea BK, et al. 3D CBCT morphometric assessment of mental foramen in Arabic population and global comparison: imperative for invasive and

non-invasive procedures in mandible. Acta Odontol Scand

;76: 98-104.

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