Prevalence and characteristics of the anterior loop in adult patients using Cone Beam computed tomography: A Cross-sectional study

Abstract

Background: The anterior loop is the extension of the inferior dental nerve which is one of the most important anatomical landmarks to consider when placing dental implants or any other surgical procedure that involves the chin region. Determining the frequency and characteristics of the anterior loop is important to reduce the risk of complications in the chin region as a result of the implant or regenerative surgeries. For this reason, the objective of the study was to determine the prevalence and characteristics of the anterior loop in adult patients using Cone Beam computed tomography. Methods: A Cross-sectional study of 93 Cone Beam computed topographies (CBCT) obtained from patients of the Faculty of Dentistry of the UNMSM during the period 2016-2017. CBCTs were analyzed and measurements of the anterior projection (AP) and caudal projection (CP) of the anterior loop were performed. In addition, the distance of the anterior loop to the alveolar ridge (D-AR) and the buccal table (D-BP) was evaluated. Results: The prevalence of the anterior loop was 95.1% (n=177) and with an average AP of 2.67 ± 1.36 mm. In AP and CP, a significant difference was evidenced concerning dental status on the right side (p <0.05). The CP of the anterior loop was 5.27 ± 1.69 mm; the rods presented a higher value on the side with 5.94 ± 2.01 mm (p = 0.01); the completely edentulous patients presented a higher value on the side with 7.00 ± 1.13 mm (p = 0.036). The D-AR was 15.33 ± 2.45 mm and the D-BP was 4.97 ± 1.40 mm. Conclusions: In this study, it was found that there is a high prevalence of the anterior loop (95.1%) with an average length of 2.67 mm. In addition, some characteristics associated with the anterior loop were found, such as its anterior projection with dental status and its caudal projection with gender and dental status.