Volume 10, Issue 2 (6-2025)
J Res Dent Maxillofac Sci 2025, 10(2): 159-167 |
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Ethics code: IR.IAU.DENTAL.REC.1400.181
Clinical trials code: not applicable
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Tahmasebi M, Heidarkhan Tehrani S, Mehmani F, Mesgari H, Mehdizadeh A. Anatomical Correlation Between Mandibular Third Molar Position and Retromolar Nerve Variations: A CBCT Study. J Res Dent Maxillofac Sci 2025; 10 (2) :159-167
URL: http://jrdms.dentaliau.ac.ir/article-1-866-en.html
URL: http://jrdms.dentaliau.ac.ir/article-1-866-en.html
Mahdis Tahmasebi1 
, Sanaz Heidarkhan Tehrani2 , Fatemeh Mehmani *3 , Hassan Mesgari4 , Amirreza Mehdizadeh2
, Sanaz Heidarkhan Tehrani2 , Fatemeh Mehmani *3 , Hassan Mesgari4 , Amirreza Mehdizadeh2
1- Dentist, Private Practice, Tehran.
2- Oral and Maxillofacial Radiology Department, TeMS.C, Islamic Azad University, Tehran, Iran.
3- Oral and Maxillofacial Radiology Department, TeMS.C, Islamic Azad University, Tehran, Iran. ,fatiii72mehmani@gmail.com
4- Oral and Maxillofacial Surgery Department, TeMS.C, Islamic Azad University, Tehran, Iran.
2- Oral and Maxillofacial Radiology Department, TeMS.C, Islamic Azad University, Tehran, Iran.
3- Oral and Maxillofacial Radiology Department, TeMS.C, Islamic Azad University, Tehran, Iran. ,
4- Oral and Maxillofacial Surgery Department, TeMS.C, Islamic Azad University, Tehran, Iran.
Abstract: (259 Views)
Background and Aim: Variations in the retromolar canal (RMC) and retromolar nerve can cause complications. This study aimed to evaluate the relationship between the anatomical position of mandibular third molars and variations of the retromolar nerve using cone-beam computed tomography (CBCT) imaging.
Materials and Methods: A descriptive analytical study was conducted on CBCT images of the mandible from 126 individuals (82 females, 44 males) over the age of 25 years. The impaction status of the mandibular third molars was classified using Pell and Gregory's classification, while angulation was determined according to Winter's classification. The presence of the retromolar nerve, its buccal or lingual position relative to the mandibular third molar, and the distance between the RMC and mandibular third molar were evaluated.
Results: The retromolar nerve was present in 53 cases (42.1%). It was positioned buccally in 36 cases (28.6%) and lingually in 17 cases (13.5%) relative to the mandibular third molar. The mean distance between the RMC and the cementoenamel junction (CEJ) of the mandibular third molar was 5.41 mm. A significant relationship was found between the third molar impaction status and presence and position of the retromolar nerve (P=0.002).
Conclusion: The retromolar nerve was more frequently present in non-impacted mandibular third molars. In presence of semi-impacted third molars, the nerve was significantly more likely to be positioned buccally. These findings highlight the importance of preoperative CBCT imaging to identify anatomical variations, aiding in surgical planning and reducing the risk of neurological complications during mandibular third molar extractions.
Materials and Methods: A descriptive analytical study was conducted on CBCT images of the mandible from 126 individuals (82 females, 44 males) over the age of 25 years. The impaction status of the mandibular third molars was classified using Pell and Gregory's classification, while angulation was determined according to Winter's classification. The presence of the retromolar nerve, its buccal or lingual position relative to the mandibular third molar, and the distance between the RMC and mandibular third molar were evaluated.
Results: The retromolar nerve was present in 53 cases (42.1%). It was positioned buccally in 36 cases (28.6%) and lingually in 17 cases (13.5%) relative to the mandibular third molar. The mean distance between the RMC and the cementoenamel junction (CEJ) of the mandibular third molar was 5.41 mm. A significant relationship was found between the third molar impaction status and presence and position of the retromolar nerve (P=0.002).
Conclusion: The retromolar nerve was more frequently present in non-impacted mandibular third molars. In presence of semi-impacted third molars, the nerve was significantly more likely to be positioned buccally. These findings highlight the importance of preoperative CBCT imaging to identify anatomical variations, aiding in surgical planning and reducing the risk of neurological complications during mandibular third molar extractions.
Type of Study: Original article |
Subject:
Radiology
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