Juxta-Apical Radiolucency: Prevalence, Characterization, and Association With the Third Molar Status

Evaluating the presence of IAN injury in patients with juxta-apical radiolucency after third molar surgery: a retrospective cohort study

Background

Juxta-apical radiolucency (JAR) has been presented as a radiographic sign, suggestive of the IAN injury through third molar surgery. This study aimed to evaluate the relation of JAR with IAN injury in cone-beam computed tomography (CBCT) images and to determine whether the presence of JAR is related to tooth angulation, proximity to the mandibular canal, position to the IAN, and thinning of the cortical plates.

Methods

Of an initial sample of 545 mandibular third molars, a total of 75 JAR⁺ and 75 JAR⁻ teeth were evaluated by CBCT. We assessed the relationship between the presence of JAR in cone-beam computed tomography (CBCT) images and the presence of IAN injury after mandibular third molar surgeries. Moreover, we investigated whether the presence of IAN injury is related to tooth angulation, proximity to the mandibular canal, position to the IAN, and thinning of the cortical plates. Descriptive statistics, Chi-square test, and Fisher’s exact test were performed for statistical analysis.

Results

A significant relationship was found between JAR and temporary IAN injury (P = 0.036). However, there was no case of permanent IAN injury. IAN injury showed no significant relationship with the tooth angulation, position to IAN and proximity to the mandibular canal, lingual cortical plate thinning, sex, and age.

Conclusions

JAR is generally in contact with the mandibular canal, and some degree of cortical thinning can be found in most cases. In this study, JAR was significantly related to temporary IAN injury. JAR may increase the risk of nerve injury during the surgical removal of third molars.

Contemplations and Ruminations of Methodological Error

PURPOSE

Journal articles in our field of oral and maxillofacial surgery are rife with case studies, cohort reviews, meta-analysis, basic science studies, surgical techniques, and anatomic studies. The data found in these studies often rely on multiple measurements by which the authors draw their conclusions. Accurate measurements play a critical role in the design of the study, which in turn affects the conclusion that the author is attempting to convey. Investigators must determine and develop the processes to determine the methodological errors associated with each project to help with determining the accuracy of these measurements. The aim of this study is to highlight some of the methodological errors contained in the material and methods in oral and maxillofacial surgery studies over the calendar years of 2018 and 2019 and how best to evaluate them.

MATERIALS AND METHODS

The inclusion criteria involved articles that used measurements where discrepancies could exist such as clinical measurements, histological measurements, and radiological measurements. The number of specimens or subjects measured in each study was tabulated.

RESULTS

Over the 2-year period considered, 744 articles were published, and 116 (15.6%) of them met the inclusion criteria. Of these articles, 37 (32%) reported a methodological error, while 79 (68%) did not. In addition, 31 (84%) of the articles with a methodological error were radiographic, while only 6 (16%) were not radiographic. Among the studies that reported methodological error, there were approximately 7 different types used with no rationale given for the choice.

CONCLUSIONS

We believe that it is important to ensure sound methods and materials, including a stated methodological error. An attempt at standardization will help to serve to enhance and strengthen the different research studies seen in our field.

Is juxta-apical radiolucency a reliable risk factor for injury to the inferior alveolar nerve during removal of lower third molars?

The aim of this study was to find out if juxta-apical radiolucency (JAR) is a reliable risk factor for injury to the inferior alveolar nerve (IAN) during removal of lower third molars. We designed a cohort study of patients whose dental panoramic tomograms (DPT) had shown JAR before complete removal of lower wisdom teeth. The outcome variable was postoperative permanent neurosensory disturbance of the IAN. A total of 39 patients (50 lower third molars) were identified and screened for permanent neurosensory disturbance. None reported any permanently altered sensation 18 months after the operation. Based on our group, the presence of JAR does not seem to be a reliable predictor of the risk of permanent injury to the IAN during removal of lower third molars.