Lingual Foramen of the Mandible on Cone-Beam Computed Tomography Scans: A Study of Anatomical Variations in an Iranian Population

Objectives: Lingual foramen (LF) is an important landmark of the mandible, which should be considered in presurgical assessment. The purpose of this study was to assess the anatomical variations of the LF using cone-beam computed tomography (CBCT). Materials and Methods: The study was conducted on 200 CBCT scans of Iranian adults. The lingual foramina (LFs) were classified into two groups by their location in the mandible namely the medial LFs (MLFs) and the lateral LFs (LLFs). The frequency of both the MLFs and the LLFs and their distance from the inferior border of the mandible were evaluated. Additionally, the diameter of the MLFs and the location of the LLFs were assessed. Data were analyzed separately for males and females. Results: All 200 participants had at least one LF. Totally, 257 LFs were detected on 200 CBCT scans, including 223 MLFs (86.6%) and 34 LLFs (13.3%). The LLF was detected in 23 patients (11.5%). The prevalence of the LLF was higher in males and in the second premolar region. The diameter of the MLFs was less than 1mm in 81% of the cases, and males had a larger MLF. Conclusion: There was a significant variability in the anatomy and location of the mandibular LF in Iranian adults. CBCT is recommended for preoperative imaging to determine the exact location and size of the LFs in the mandible to prevent possible surgical complications.

Do Morphological Changes in the Anterior Mandibular Region Interfere with Standard Implant Placement? A Cone Beam Computed Tomographic Cross-Sectional Study

Objective. To determine the morphological features in the anterior mandibular region, the presence of lingual foramen and canal dimensions in Saudi subjects that would interfere with standard implant placement. Methods. CBCT scans of patients seeking implant treatment were examined. Based on the dentition status, patients were categorized into edentulous (group I) and dentulous (group I). On the panoramic view, the distance between the two mental foramina was divided into vertical segments of 10 mm width. In each segment, vertical bone height and buccolingual thickness at three levels (alveolar crest, 5 mm, and 10 mm apical to the crest) were assessed. The lingual foramen prevalence and canal features were assessed as well. Comparisons between the two groups regarding the assessed parameters were performed using the t-test. The percentage of edentulous mandibles with thickness <6 mm corresponding to the standard implant diameter was also calculated. Results. Following the inclusion and exclusion criteria, group I consisted of 45 subjects and group II comprised 26 subjects. Bone height and thickness at the crestal level were significantly less in edentulous (I) than dentate mandibles (II) ( P < 0.0001 ). The lingual foramen was detected in 90% of patients. In both groups, males had significantly greater mandibular height than females ( P = 0.02 and 0.005). At the crestal level, the thickness was <6 mm in 50% of the anterior mandibular segments. Conclusion. Half of the edentulous patients may receive normal size implants in the anterior interforaminal segments, while the other half will be limited to narrow implants (3.5 mm and less). The lingual foramen location, canal size, and position may represent another limitation for implant placement in that segment.

Using Panoramic Radiograph for Identification of Mandibular Structures: A Study on Bangladeshi Population

Background: Panoramic view of radiograph or Orthopantomogram (OPG) is useful in the aspect of surgery done in mandible, as many visible landmarks can be found in a single tomographic image. Objectives: To evaluate the visibility of anatomical structures of mandible in OPG and to determine the relationship of age and gender with this. Materials and Methods: It was a cross-sectional study and was conducted in dental OPD of Noakhali General Hospital from January 2019 to June 2019, six-month period. Data were analyzed by SPSS version 20. Results: A Total of 272 OPGs were examined of patients (female 165, male107), having age range of 7-90 years. Here highest visible structure was mandibular canal (about 97.4%) followed by mental foramen and mandibular foramen, where visibility was 92.3% and 87.5% respectively. Anterior loop of mental nerve and incisive canal were seen in 33.5% and 31.6% cases respectively. Only in 15.1% OPG, lingual foramen was visible. There is no significant relationship between gender and visibility of structures (p>0.05). Age and visibility of landmarks showed significant relation only in case of mental foramen and mandibular canal (p<0.05). Conclusion: Panoramic view or orthopantomogram is very efficient to detect many anatomic points in adults. KYAMC Journal Vol. 11, No.-3, October 2020, Page 133-136

Prevalence and position of mandibular incisive canal, anterior loop of the mandibular canal and lingual foramen using cone beam computed tomography

Objective: Comprehensive knowledge about the anatomy of the surgical site is an important prerequisite for any surgical procedure. This study aimed to assess the prevalence, position and anatomical characteristics of mandibular incisive canal (MIC), lingual foramen (LF) and anterior loop of the mandibular canal (ALMC) in an Iranian population using cone beam computed tomography (CBCT). Materials and Methods: This study was conducted on 103 patients who underwent CBCT prior to implant placement. The CBCT scans of patients were evaluated by two observers to determine the visibility and length of MIC, LF and ALMC. The buccolingual inclination of MIC at the initiation point of canal and canal path were also studied. Results: The prevalence of MIC, LF and ALMC was 90%, 76% and 84% on CBCT scans, respectively. The mean length of MIC and ALMC was 7.5mm and 1.2mm, respectively and the mean width of LF was 0.9mm. The MIC had a buccal inclination at the initiation point and approximated the lingual plate as extended towards the midline. Analytical statistics including independent samples t-test, paired samples t-test, ANOVA analyses were applied. Conclusion: Considering the high prevalence of MIC, ALMC and LF and wide range of MIC (1.2mm to 20mm) and ALMC (1mm to 9.9mm) length, CBCT is recommended for patients prior to surgical procedures in the anterior mandible to determine the exact location of these anatomical structures.

Evaluation of medial lingual foramen with cone-beam computed tomography in a Turkish adult population

Aim: The aim of this study is to characterize the anatomical findings of the MLF in a Turkish population, using cone-beam computed tomography (CBCT). Methodology: The CBCT images of 350 untreated patients (164 male, 186 female ranging in age between 18 and 65) were included in this study. The distribution of MLFs were determined in axial, sagittal, and coronal planes by considering gender and side. For statistical evaluation, a chi-square test was used to analyze independent samples. P<0.05 was considered statistically significant. Results: At least 1 canal was observed in all subjects (n = 350). The most common result was a single canal. Among the 164 male patients (46.86%), 98 had 1 canal (59.75%); 59 had 2 canals (35.97%); and 7 had 3 canals (4.26%). Among the 186 female patients (53.14%), 134 (72.04%) had 1 conduit or canal; 49 (26.34%) had 2 canals; and only 3 case (1.61%) presented with 3 canals. Difference between genders was statistically significant. Conclusions: Vascular canals and anastomoses presence in anterior mandible which are sufficient for severe hemorrhage complications. The distribution of MLFs must be taken into account during presurgical planning.