Prevalence, Patterns and Variations of Anterior Loop of Inferior Alveolar Nerve—A CBCT Based Retrospective Study

The anterior loop of the inferior alveolar nerve is a sensitive anatomical feature that should be taken into account during installation of dental implants anterior to the mental foramen. This study was conducted to explore the controversy regarding prevalence and length. A total of 452 mandible quadrants of 234 patients (age: 50.1 ± 13.3 years, 113 males, 121 females) were studied using cone-beam computerized tomography. After reconstructing axial, frontal, and sagittal slices, the region between the most anterior point on the mental foramen and the most anterior part of the mandibular nerve was inspected for signs of anterior loop presence. If positive, the length of the anterior loop was measured in mm as the distance between the anterior border of mental foramen and the anterior border of the loop. Prevalence and length of the anterior loop were compared statistically between sexes and age groups. The anterior loop was observed in 106 quadrants (23.5% of 451 quadrants) of 95 patients (40.6% of 234 patients), of whom 11 had bilateral anterior loops. Prevalences were similar in males (41%) and females (39%, chi-square P =.791). The mean anterior loop length was 2.77 ± 1.56 mm (95% CI: 2.5–3.1 mm), without significant sex (regression beta = −0.159, P = .134) or age (beta = −0.059, P = .578) differences. The anterior loop might exist in about 40% of patients, regardless of their gender. The mean safe anterior distance from the anterior loop is about 3 mm + (2.5–3.1 mm) = 5.5–6.1 mm, regardless of age.

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Inferior Alveolar Nerve Injuries Associated with Mandibular Fractures at Risk: A Two-Center Retrospective Study

Craniomaxillofacial Trauma & Reconstruction ◽

10.1055/s-0034-1375169 ◽

2014 ◽

Vol 7 (4) ◽

pp. 280-283 ◽

Cited By ~ 6

Author(s):

Paolo Boffano ◽

Fabio Roccia ◽

Cesare Gallesio ◽

K. Karagozoglu ◽

Tymour Forouzanfar

Keyword(s):

At Risk ◽

Retrospective Study ◽

Medical Center ◽

Maxillofacial Surgery ◽

Inferior Alveolar Nerve ◽

Mandibular Fractures ◽

Nerve Injuries ◽

Mandibular Angle ◽

Maxillofacial Fractures ◽

Angle Fractures

The aim of the study was to investigate the incidence of the inferior alveolar nerve (IAN) injury in mandibular fractures. This study is based on two databases that have continuously recorded patients hospitalized with maxillofacial fractures in two departments—Department of Maxillofacial Surgery, Vrije Universiteit University Medical Center, Amsterdam, the Netherlands, and Division of Maxillofacial Surgery, San Giovanni Battista Hospital, Turin, Italy. Demographic, anatomic, and etiology variables were considered for each patient and statistically assessed in relation to the neurosensory IAN impairment. Statistically significant associations were found between IAN injury and fracture displacement ( p = 0.03), isolated mandibular fractures ( p = 0.01), and angle fractures ( p = 0.004). A statistically significant association was also found between IAN injury and assaults ( p = 0.03). Displaced isolated mandibular angle fractures could be considered at risk for increased incidence of IAN injury. Assaults seem to be the most important etiological factor that is responsible for IAN lesions.

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Neurosensory function of the inferior alveolar nerve after bilateral sagittal ramus osteotomy: a retrospective study of 68 patients

International Journal of Oral and Maxillofacial Surgery ◽

10.1016/j.ijom.2004.10.021 ◽

2005 ◽

Vol 34 (5) ◽

pp. 495-498 ◽

Cited By ~ 51

Author(s):

S. Nesari ◽

K.-E. Kahnberg ◽

L. Rasmusson

Keyword(s):

Retrospective Study ◽

Inferior Alveolar Nerve

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Position of the Mandibular Foramen in Different Facial Shapes Assessed by Cone-Beam Computed Tomography - A Cross-Sectional Retrospective Study

The Open Dentistry Journal ◽

10.2174/1874210601913010544 ◽

2019 ◽

Vol 13 (1) ◽

pp. 544-550

Author(s):

Silvan Correa ◽

Rogério H. Lopes Motta ◽

Milena B. Fellipe Silva ◽

Sidney R. Figueroba ◽

Francisco C. Groppo ◽

...

Keyword(s):

Computed Tomography ◽

Retrospective Study ◽

Cone Beam Computed Tomography ◽

Inferior Alveolar Nerve ◽

The Other ◽

Cone Beam ◽

Inferior Alveolar Nerve Block ◽

Mandibular Ramus ◽

Cross Sectional ◽

Mandibular Foramen

Purpose: The mandibular foramen, located on the internal surface of the mandibular ramus, is an important anatomical landmark for the success during the inferior alveolar nerve block. This cross-sectional retrospective study aimed to evaluate the location of the mandibular foramen through Cone-Beam Computed Tomography (CBCT) in different facial shapes. Materials and Methods: The determination of the location of the mandibular foramen was performed using CBCT of mesocephalic, dolichocephalic and brachycephalic patients (n=40 each). The ramus width (W), the distance from the mandibular foramen to the deepest point of the anterior border of the mandibular ramus (D), the distance from the mandibular foramen to the lowest point of the mandibular notch (V) and the distance from the inferior border of the mandible to the lowest point in of the mandibular border (R), as well as the ratios W/D and V/R, were measured. ANCOVA, two-way ANOVA and Chi-square tests were used to analyze the variation among the facial shapes. Results: The ramus width (W) was greater (p<0.0001) in the brachycephalic (28.4±0.5 mm) than in both mesocephalic (26.8±0.36 mm) and dolichocephalic (25.5±0.39 mm) patients. D (p=0.0433) and R (p=0.0072) were also greater in the brachycephalic (17.7±0.36 mm; 43.4±0.75 mm, respectively) than dolichocephalic (16.5±0.3 mm; 40.3±0.63 mm, respectively), but both did not differ from mesocephalic (17.3±0.36 mm; 41.8±0.66 mm, respectively) patients. The other measurements (V, W/D and R/V) did not significantly differ among facial shapes. Conclusion: The localization of the mandibular foramen was, in the horizontal direction, more posterior in the brachycephalic patients and, in the vertical direction, higher in the dolichocephalic patients, when compared to the other groups analyzed. Thus, the anatomic data found in this study may help dentists to increase the success of the inferior alveolar nerve block and prevent surgical complications.

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