Evaluation of incidence of mental nerve loop in Central India population using cone beam computed tomography.

CONTEXT: Anatomical literature has described the anterior loop being an extension of the mental nerve which is present anterior to the mental foramen while the caudal loop has been described as the distance between the lower border of the mental foramen and the lowest point of the mandibular canal. The knowledge and identification of the anterior and caudal loop of the mental nerve are important in surgical procedures performed around the mental foramen to avoid inadvertent damage to these vital structures resulting in postoperative complications. AIM: The present study was conducted to determine the incidence and measurement of mental nerve loop in the mandibular arches using cone beam computed tomography (CBCT). SETTINGS AND DESIGN: A total of 200 CBCT images were retrieved and inspected for the presence of the mental nerve loop. The length of the anterior loop was measured by counting the number of consecutive contiguous vertical cross sections displaying two round hypodense images. This number was multiplied by the thickness of the slices. The caudal loop was measured as the distance between the lower border of the mental foramen and the lowest point of mandibular canal. STATISTICAL ANALYSIS USED: Shapiro-Wilk test and Mann-Whitney U-test were used. P < 0.05 was considered statistically significant. RESULTS: 57.5% (n = 200 scans) presented with the anterior loop of the mental nerve with a mean length of 0.50 mm and 0.37 mm on the right side and left side, respectively. All the samples of CBCT scans taken were having caudal loop extension with a mean length of 3.53 mm. CONCLUSION: A considerable number of individuals (57.5%) in the present study presented with the anterior loop of the mental nerve. CBCT was found to be an effective imaging modality for the detection of anterior loop of the mental nerve.

A Focus on Variation in Morphology of Soft Palate Using Cone-Beam Computed Tomography with Assessment of Need's Ratio in Central Madhya Pradesh Population.

INTRODUCTION: Soft palate is an anatomical structure that helps in modifying the quality of voice and to breathe while swallowing. Through the variants and shapes of the soft palate, we can assess the age and gender of an individual. AIM: The aim of the present study was to investigate the variation in morphology of soft palate and to find its association with the Need's ratio, Velar Length (VL), Velar Width (VW) and Pharyngeal Depth (PD), in age groups and gender using CBCT in Central Madhya Pradesh population. MATERIALS AND METHODS: The study sample consisted of 121 CBCT scans of individuals aged between 15 to 45 years. These scans were retrieved from the Department of Oral Radiology. The velar morphology on CBCT was examined and grouped into six types. The results obtained were subjected to a statistical analysis to find the association between variants of the soft palate with gender and different age groups. ANOVA and Z-test were used for statistical analysis. The p≤0.05 was considered as significant while p≤0.001 was considered as highly significant. RESULTS: The most frequent type of soft palate was rat tail shaped. The mean VL and VW values were significantly higher in males while PD and Need's ratio were higher among females, insignificantly associated with the types of soft palate. A significant association was observed between the mean VL and VW with various age groups, showing an increase in values with an increase in age. CONCLUSION: A variation in morphology of soft palate plays an important role in the assessment of velopharyngeal closure and in diagnosing obstructive sleep apnoea individuals.