Assessment of Anterior Loop of Inferior Alveolar Nerve and Its Anatomic Variations with Age, Gender, and Dentition Status in Indian Population: A CBCT Study

A Retrospective CBCT Evaluation of the Inferior Alveolar Nerve's Anterior Loop in Odisha People

Background

The anterior loop of the inferior alveolar nerve is the portion of the nerve that is located anterior to the mental foramen before it exits the canal.

Objectives

The objective of the research was to assess anterior loop in the Odisha population.

Materials and Methods

For this study, a random selection of 100 CBCT scans representing 200 hemi-mandibles was made. Descriptive statistics were used to compute the distribution of the mental nerve pattern according to gender, age, and the presence or absence of dysplastic features. Frequency and percentages were then used to show the results.

Results

There was significant difference among male and female on left and right side for anterior loop. 28% of studied population had loop and 72% without loop out of 100 participants. Pattern III was common type followed by patter I. Right side had slightly more loop than left side. Loop length distribution was significant.

Conclusions

It was concluded that loop is a common finding; hence it must be evaluated before doing any surgical procedure in that anatomical location.

Prevalence and management of neuropathic injury caused by dental implant insertion in mandible: a systematic review

To synthesize scientific knowledge regarding the prevalence of neuropathies and nerve injuries caused by dental implant placement in mandible and the available management. Observational and interventional studies evaluating neuropathies occurrence in adults who underwent dental implant surgery were included. Any neuropathy diagnostic was accepted. The searches were conducted in six databases and grey literature. Methodological quality was screened using the Joanna Briggs Institute. The resulting synthesis was a narrative summary, and prevalence meta-analyses were performed in MetaXL 5.3. Among 98 full texts assessed, 38 studies were included. Neuropathies were diagnosed by questionnaires and/or clinical assessment. Eighteen studies presented high, sixteen moderate, and four low methodological quality. In implant surgeries without nerve lateralization, 12% and 5% of the patients may experience neuropathy during the first week and after three months, respectively. In implant surgeries with nerve lateralization, the prevalence was from 90% in the first week to 42% after three months. Proposed management included drugs, laser therapy and dental implant removal. In mandible, the prevalence of neuropathies in dental implant surgeries without lateralization is lower when compared with those with lateralization (eight times more in both follow-up times). The most frequent treatment was pharmacologic management.

Identification of the Incisive Branch of the Inferior Alveolar Nerve of Edentulous Mandibles Using Cone-Beam Computerized Tomography

This study explored the average length of the incisive branch (IB) of the inferior alveolar nerve on cone-beam computerized tomography (CBCT) with regard to patient demographics in patients with edentulous mandibles. CBCT was used in a retrospective study of edentulous mandibles to assess the presence and anatomical variation for the IB. Three independent observers measured bilateral IB lengths. In addition to demographics, IB length and port of exit data were obtained. A 1-way analysis of variance was used to test whether IB length varied by sex or port of exit, and a standard Pearson correlation was used to test for IB length and age significance, with a significance level of P < .05. Intraclass correlation coefficients showed significant agreement in IB length across all observers. No significant difference was noted between the exit port and IB length. An important effect was reported for sex, indicating women have generally shorter IB lengths (9.43 ± 3.99 vs 10.55 ± 3.92). There was a significant correlation with age, but the relationship was weak. Edentulous mandibles have an altered anatomic landscape, and establishing predictive IB dimensions aids practitioners in surgical planning.

Assessment of the Anterior Loop and Pattern of Entry of Mental Nerve Into the Mental Foramen: A Radiographic Study of Panoramic Images

INTRODUCTION

The precise location of the mental foramina is an essential landmark in planning the position of dental implants in the anterior mandible. Injury to inferior alveolar nerve during anterior mandibular implant surgery causes altered sensation which greatly affects patient satisfaction.

METHODS

In this study, we assessed the prevalence of anterior loop of mental nerve and the pattern of entry of mental nerve into the mental foramen. Three hundred panoramic radiographs (600 hemimandibles) obtained from records maintained in the Department of Oral Medicine and Radiology were randomly selected for the study. The radiographs were evaluated by two independent observers for the pattern of entry of mental nerve into the mental foramen on either side of the mandible and for the presence or absence of anterior loop of mental nerve.

RESULTS

The most prevalent pattern of mental nerve observed was Straight pattern which totals to 67.5% followed by Anterior loop pattern (18.8%) and then the Perpendicular pattern (13.7%). There was no significant association between the gender and subtypes of looping pattern on the left and right side and a highly significant association between the side of the mandible and loop pattern was observed by Chi square test.

CONCLUSION

The Anterior loop pattern of mental nerve has been found in 18.8% of the population suggesting to accurate planning with three-dimensional imaging techniques to avoid injury to mental nerve during dental implant placement and other surgical procedure involving the interforaminal region of the mandible.

Automated segmentation of the mandibular canal and its anterior loop by deep learning

Accurate mandibular canal (MC) detection is crucial to avoid nerve injury during surgical procedures. Moreover, the anatomic complexity of the interforaminal region requires a precise delineation of anatomical variations such as the anterior loop (AL). Therefore, CBCT-based presurgical planning is recommended, even though anatomical variations and lack of MC cortication make canal delineation challenging. To overcome these limitations, artificial intelligence (AI) may aid presurgical MC delineation. In the present study, we aim to train and validate an AI-driven tool capable of performing accurate segmentation of the MC even in the presence of anatomical variation such as AL. Results achieved high accuracy metrics, with 0.997 of global accuracy for both MC with and without AL. The anterior and middle sections of the MC, where most surgical interventions are performed, presented the most accurate segmentation compared to the posterior section. The AI-driven tool provided accurate segmentation of the mandibular canal, even in the presence of anatomical variation such as an anterior loop. Thus, the presently validated dedicated AI tool may aid clinicians in automating the segmentation of neurovascular canals and their anatomical variations. It may significantly contribute to presurgical planning for dental implant placement, especially in the interforaminal region.