Determining Safe Zone in Anterior Mandible Related to the Genial Tubercle for Implant Placement using Cone Beam Computed Tomography in Ahvaz Jundishapur Dental School

Razavi, Mahshid; Shirafkan, Saeed; Mousavi, Seyyedeh Elham; Shishe Saz, Farnaz

doi:10.32592/JSMJ.23.4.341

Determining Safe Zone in Anterior Mandible Related to the Genial Tubercle for Implant Placement using Cone Beam Computed Tomography in Ahvaz Jundishapur Dental School

Document Type : Original Article

Authors

Mahshid Razavi ¹

Saeed Shirafkan ²

Seyyedeh Elham Mousavi ³

Farnaz Shishe Saz ⁴

¹ Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

² Assistant Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

³ Resident, Department of Oral and Maxillofacial Radiology, School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

⁴ Dentist, Department of Oral and Maxillofacial Radiology, School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

10.32592/JSMJ.23.4.341

Abstract

Background and Objectives Surgeries in the anterior mandible such as implant placement in the interforaminal area or chin grafting may damage the anterior loop of the mental nerve, resulting in neurosensory disturbances. Given the significance of genial tubercles in delineating the safe zone for mandible treatment planning, this study aims to establish the optimal implant placement zone in the anterior mandible relative to genial tubercle location.
Subjects and Methods This study analyzed 96 CBCT images from patients treated at the Oral and Maxillofacial Radiology Department of Ahvaz Jundishapur School of Dentistry. The anatomies of the anterior mandible areas were studied based on the coronal sections, as well as the axial and cross sectional images, while the genial tubercles, mental foramen, and the anterior loop of inferior alveolar nerve were marked on each side.
Results The mean distance from the genial tubercles to the mesial margin of the mental foramen was 22.44 ± 2.23 mm overall, 22.41 ± 2.20 mm on the left side, and 22.47 ± 2.27 mm on the right side. The mean distance from the genial tubercles to the mesial margin of the anterior loop was 21.03 ± 2.43 mm overall, 21.19 ± 2.58 mm on the left side, and 20.70 ± 2.21 mm on the right side. The mean safe zone was 36.47 ± 2.75 mm overall, 18.15 ± 2.36 mm on the left side, and 18.07 ± 2.21 mm on the right side. Statistical analysis revealed that the mean safe zone in the anterior mandible is 36.24 ± 2.75 mm.
Conclusion The mean distance from the genial tubercle to the mesial of the left mental foramen, the mean distance from the genial tubercle to the mesial of the left anterior loop, and the mean left safe zone were found to be smaller in women. However, this difference was not statistically significant. The mean distance from the genial tubercle to the mesial of the mental foramen overall and on the right side, the mean distance from the genial tubercle to the mesial of the anterior loop overall and on the right side, the mean safe zone overall and on the right side, and the mean safe zone in the anterior mandible were all smaller in women. This difference was statistically significant. No significant differences were observed between different age groups for any of the distances. A statistically significant difference was found between the left and right sides when comparing the distance from the genial tubercle to the mesial of the anterior loop.
Background and Objectives Surgeries in the anterior mandible such as implant placement in the interforaminal area or chin grafting may damage the anterior loop of the mental nerve, resulting in neurosensory disturbances. Given the significance of genial tubercles in delineating the safe zone for mandible treatment planning, this study aims to establish the optimal implant placement zone in the anterior mandible relative to genial tubercle location.
Subjects and Methods This study analyzed 96 CBCT images from patients treated at the Oral and Maxillofacial Radiology Department of Ahvaz Jundishapur School of Dentistry. The anatomies of the anterior mandible areas were studied based on the coronal sections, as well as the axial and cross sectional images, while the genial tubercles, mental foramen, and the anterior loop of inferior alveolar nerve were marked on each side.
Results The mean distance from the genial tubercles to the mesial margin of the mental foramen was 22.44 ± 2.23 mm overall, 22.41 ± 2.20 mm on the left side, and 22.47 ± 2.27 mm on the right side. The mean distance from the genial tubercles to the mesial margin of the anterior loop was 21.03 ± 2.43 mm overall, 21.19 ± 2.58 mm on the left side, and 20.70 ± 2.21 mm on the right side. The mean safe zone was 36.47 ± 2.75 mm overall, 18.15 ± 2.36 mm on the left side, and 18.07 ± 2.21 mm on the right side. Statistical analysis revealed that the mean safe zone in the anterior mandible is 36.24 ± 2.75 mm.
Conclusion The mean distance from the genial tubercle to the mesial of the left mental foramen, the mean distance from the genial tubercle to the mesial of the left anterior loop, and the mean left safe zone were found to be smaller in women. However, this difference was not statistically significant. The mean distance from the genial tubercle to the mesial of the mental foramen overall and on the right side, the mean distance from the genial tubercle to the mesial of the anterior loop overall and on the right side, the mean safe zone overall and on the right side, and the mean safe zone in the anterior mandible were all smaller in women. This difference was statistically significant. No significant differences were observed between different age groups for any of the distances. A statistically significant difference was found between the left and right sides when comparing the distance from the genial tubercle to the mesial of the anterior loop.

Keywords

Cone beam computed tomography

Inferior alveolar canal and anterior loop

Genial tubercle

Dental implants

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