Evaluation of Relative Position of Mandibular Foramen in Children as a Reference for Inferior Alveolar Nerve Block using Orthopantamograph

Abstract

Introduction: The Mandibular Foramen (MF) is a landmark for administering local anaesthetic solution for Inferior Alveolar Nerve Block (IANB). The position of MF shows considerable variation among different ethnicity, ages and on either sides even within the same individual. Failure to achieve IANB leading to repeated injection of the local anaesthetic solution will not only pose a behaviour problem in children but can also lead to systemic toxic level of anaesthetic solution being administered. Aim:To determine the relative position of the mandibular foramen in 7 to 12-year-old children in relation to the mandibular occlusal plane and the deepest point on coronoid notch. Materials and Methods:Ninety orthopantamograph of 7 to 12-year-old children were selected from the database and were divided into three groups: Group 1 (G1): seven to eight-year-old, Group 2 (G2): 9 to 10-year-old and Group 3 (G3): 11 to 12-yearold. The radiographs were traced on acetate paper, anatomical landmarks were marked and linear measurements were noted from the Mandibular Lingula (ML) to the occlusal plane, and to the deepest point on coronoid notch. The data obtained was tabulated and subjected to statistical analysis. One way ANOVA test followed by Bonferroni post hoc analysis and Student's paired t-test were used.Results: Mandibular foramen is approximately, 2-3 mm above the occlusal plane and 11.6-13.0 mm from deepest point of coronoid notch for seven to eight-year-old children, 3-4 mm above the occlusal plane and 13.0-13.9 mm from deepest point of coronoid notch for 9-10 year age group and 5.5-6.5 mm above the occlusal plane and 11.9-12.2 mm from deepest point of coronoid notch for children of the ages 11-12 years. The linear distance from the deepest point of coronoid notch to the mandibular lingula showed statistical significance in G2 vs G3 on right side G1 vs G2 and G2 vs G3 on the left side. The variance of this distance for either side showed statistical significance for G1 and G2. Conclusion:The distance from the mandibular lingula to the occlusal plane showed gradual increase in all the three groups, which was statistically significant. The position of the mandibular foramen is not bilaterally symmetrically for any of the considered age groups.Navin Hadadi Krishnamurthy et al., Mandibular Foramen Location in Children www.jcdr.net

The mandibular plane: a stable reference to localize the mandibular foramen, even during growth

“…No significant differences between the measurements on the right and left were observed as in other studies [14,19,22,26,29]. Facial symmetry was respected.…”

“…Six other studies have analyzed the mandibular lingula (ML) position on panoramic radiographs [6,11,14,19] or on CBCT [24,25]. The ML is a tongue-shaped bony projection on the medial surface of the mandibular ramus [24], situated superiorly and anteriorly to the mandibular foramen [16].…”

“…Kanno found that the lingula was above the OP in 70% of girls and 55% of boys in the 7 years old group and in 85% of all children by age 10 [11]. Krishnamurthy described the location of the ML of 2-3 mm above the occlusal plane in 7 and 8 years old children, increasing until 6 mm for children of the ages 11-12 years [14]. In Sekerci study [24] using CBCT, the authors reported a mean height level of the mandibular lingula of 2 mm above the occlusal plane.…”

“…Many studies have tried to determine its position, but the results are often contradictory Frédéric Vaysse and Emmanuelle Noirrit contributed equally. and the reference landmarks are sometimes difficult to identify clinically, especially in children [6,[11][12][13][14]. Previous attempts to determine the position of the MF relative to the occlusal plane have mainly been based on dry mandibles [7,15,16] or on 2D radiographs which were deformed (panoramic radiographs [6,[11][12][13][14][17][18][19]) and/or had a high level of anatomical superimposition (lateral cephalometric radiographs [20,21]).…”

“…and the reference landmarks are sometimes difficult to identify clinically, especially in children [6,[11][12][13][14]. Previous attempts to determine the position of the MF relative to the occlusal plane have mainly been based on dry mandibles [7,15,16] or on 2D radiographs which were deformed (panoramic radiographs [6,[11][12][13][14][17][18][19]) and/or had a high level of anatomical superimposition (lateral cephalometric radiographs [20,21]). Nowadays, the development of 3D computer software combined with computed tomography (CT) allows indisputable data on the mandibular foramen location to be produced [10,[22][23][24][25][26][27][28][29].…”