Cone beam computed tomography study on the relation between mental foramen and roots of mandibular teeth, presence of anterior loop and satellite foramina

Prevalence of accessory mental foramen and lateral lingual foramen using cone beam computed tomography: A single-center cross-sectional study

PURPOSE

This study aimed to assess the prevalence, dimensions, and positions of accessory mental foramen (AMF) and lateral lingual foramen (LLF) in an Iranian population using cone beam computed tomography (CBCT).

METHODS AND MATERIALS

In this cross-sectional study, CBCT images of 2082 patients were retrospectively reviewed based on inclusion criteria, including images from the mandibular region taken in the past five years with accurate demographic data. Exclusion criteria included images with significant pathologies, fractures, or poor quality. CBCT images were captured, and AMF and LLF presence (primary outcome variable), dimensions, and positions (secondary outcome variables) were recorded relative to the mental foramen and adjacent teeth. Data analysis was performed using the Chi-square test with a 5% significance level.

RESULTS

A total of 2082 CBCT samples (46.54% females and 53.46% males) with a mean age of 48.30 ± 12.70 years were examined. Among these, 246 AMFs were observed in 222 individuals with a prevalence at the foramen level of 11.815%, with 24 having two AMFs. AMF was mostly observed unilaterally, with bilateral occurrence noted in 10.81% of patients with AMF. Additionally, 86 patients were found to have LLF with a prevalence at the foramen level of 5.907%. There were no significant differences between genders in AMF and LLF prevalence.

CONCLUSION

AMF and LLF were detectable using CBCT in the selected Iranian population. AMF was commonly situated posterior and superior to the mental foramen, while LLF was often found near the first premolar. This knowledge is crucial for preventing nerve injury during surgery and ensuring effective nerve block procedures.

The anterior loop of the inferior alveolar nerve within the mentonian foramen: a scoping review

PURPOSE

The aim of this study is to delineate the safety zone concerning the anteriorization of the AL and correlate it with the behavior of the AL, analyzing its feasibility.

METHODS

Adhering to the Joanna Briggs Institute (JBI) manual guidelines, both the protocol and this review were conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist. MeSH terms, combined with free terms, were utilized to search for articles in the following databases: Embase, LILACS, LIVIVO, PubMed/MEDLINE, Scopus, Web of Science, and grey literature.

RESULTS

Fifteen articles were select following the eligibility criteria. An average safe zone of 4.75 mm in humans was observed, with a prevalence 60.8% and average anterior length of the AL of 2.09 mm in humans.

CONCLUSION

The AL has varied patterns across different populations, then, it could not be asserted a 100% safe zone. Preoperative analysis of the AL with CBCT is always necessary. While it could be stated that a safe zone should be employed as an inviolable region, stipulated measures of a safe zone should be regarded as an area of greater attention in preoperative planning.

Influence of CBCT-derived panoramic curve variability in the measurements for dental implant planning

OBJECTIVE

To investigate whether the curve markings performed prior to panoramic and cross-sectional reconstructions can influence the planning of oral implants.

METHODS

Twenty oral radiologists landmarked the reference panoramic curves in 25 CBCT scans of the mandible. Bone height was measured on the resulting cross-sectional slices in the edentulous region of the lower first molar. The following data were recorded: (1) number of landmarks used to build each reference curve; (2) shape of the reference curve (inverted "U", inverted "V" or "horseshoe"); and (3) measurement in the first molar region. The data were assessed for variability based on the number of landmarks, the shape of the reference curve, and the measurements obtained.

RESULTS

The number of landmarks used to guide the panoramic reconstruction varied among radiologists (p < 0.05), but most of them draw curves in inverted "U" shape (68-100%). The reproducibility of the measurements taken in the edentulous mandibular first molar region was excellent (84.7%). The number of landmarks and the shape of the curve did not have a significant influence on the reproducibility of the measurements (p > 0.05).

CONCLUSION

Variations of the operator-dependent steps during the panoramic reconstructions occur but do not play a significant part changing the measurements taken for oral implant planning.

Prevalence and extension of the anterior loop of the mental nerve in different populations and CBCT imaging settings: A systematic review and meta-analysis

Purpose

Materials and Methods

Results

Conclusion

Evaluation of Mental Foramen with Cone Beam Computed Tomography: A Systematic Review of Literature

Purpose

The aim of this systematic review is to assess whether the anatomy of mental foramen is precisely evaluable with cone beam computed tomography (CBCT) before implantation in humans.

Methods

A systematic review was carried out to evaluate the anatomy of mental foramen (size, position, symmetry, anterior loop, and accessory mental foramen or multiple mental foramina). According to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, an electronic search of three databases (Medline, Web of Science, and Cochrane Library) was undertaken until June 2020 and was supplemented by manual searching. Two reviewers will independently perform the processes of study inclusion, data extraction, and quality assessment. Systematic reviews, studies about children, and case reports were excluded. Only studies using CBCT to do preoperative evaluation were selected.

Results

From 728 potentially eligible articles, 72 were included in the qualitative analysis and quantitative synthesis. This systematic review provided an assessment of the anatomy of the mental foramen. The mental foramen was located mostly between the two premolars (between 50.4% and 61.95%) or apically to the second premolar (from 50.3% to 57.9%). The mean diameter of the mental foramen was bigger in males than in females; the difference between them could reach 0.62 mm. The anterior loop seemed to be longer in males (between 0.87 ± 1.81 and 7.25 ± 2.02 mm) than in females (between 0.81 ± 1.18 and 6.52 ± 1.63 mm) and with the presence of teeth (from 0.91 ± 1.18 to 2.55 ± 1.28 for dentate people and from 0.25 ± 0.61 to 2.40 ± 0.88 mm for edentate population). The anterior loop and the accessory mental foramina were detected more frequently with CBCT than panoramic X-ray: only between 0.0 and 48.6% AMFs detected with CBCT were also seen with panoramic images. Clinical Significance. The mental foramen (MF) is an important landmark for local anesthesia and surgical and implantology procedures. Its location, morphology, and anatomical variations need to be considered to avoid mental nerve injury. The aim of this review is to evaluate the mental foramen using CBCT through a systematic literature review to improve knowledge of this complex area for the clinician.

Alveolar antral artery in edentulous patients and their visualization through cone beam computed tomography

OBJECTIVE OF THE STUDY

The aim of this study was to assess the anatomical features of the alveolar antral artery (AAA) in edentulous patients using cone beam computed tomography (CBCT).

PATIENTS

The sample consisted of 191 CBCT scans of maxillary sinuses (n=382) of male (n=59) and female (n=132) edentulous patients (age: 38-89 years).

MATERIAL AND METHODS

The images were analyzed in Dolphin™ 11.9 software. Visualization, location, and diameter of the AAA was registered.

RESULTS

AAA was present in 88.5% of the assessed maxillary sinuses. Bilateral visualization was predominant 77% (P<0.0001). The mean vertical distance from the most anterior part of the AAA to the sinus floor was 7.9±6mm in female patients (both sides) and 12±7.22mm on the right side and 10.9±6.86mm on the left side in males. The mean diameter of the AAA was 1.2±0.7mm on both sides in females. In males, the diameter was significantly (P<0.05) larger: 1.5±0.62mm on the right side and 1.4±0.69 on the left side in females.

CONCLUSION

The AAA had a higher visualization rate, better visualization, and larger diameter when it was present bilaterally in male and female patients.