Digital Orthopantomogram Research Articles

Accuracy of Mandibular Foramen Localization Using Digital Orthopantomogram (OPG) in Middle Eastern Population.

Locating the mandibular foramen (MF) through imaging is clinically important for inferior alveolar nerve (IAN) anesthesia and mandibular ramus osteotomies. Although cone-beam computed tomography (CBCT) is superior in imaging the mandible, an orthopantomogram (OPG) is preferred for its ease of use and availability. Therefore, the present study aimed to evaluate the accuracy of digital OPG in localizing the MF, in a subset of the Middle Eastern population. Radiographic images (OPG and CBCT) of selected patients (adults, dentulous and no mandibular abnormalities) were used to locate the MF through digital measurements (mm) of the anteroposterior distance from the anterior border of the ramus (MF-AP) and the superoinferior position from the mandibular occlusal plane (MF-SI). Measurements were statistically compared between OPG and CBCT for accuracy. Differences in measurements between OPG and CBCT were compared against the anatomic location (right/left), age and biological sex, assuming a p-value < 0.05 as significant. A total of 204 radiographic records (males: 100/females: 104/mean age: 34.65 ± 11.55 years) were evaluated. The measurements for the MF were MF-AP-OPG (right: 13.53 ± 2.44/left: 13.19 ± 2.25), MF-AP-CBCT (right: 13.61 ± 2.39/left: 13.36 ± 2.19), MF-SI-OPG (right: 5.25 ± 1.71/left: 5.41 ± 1.65) and MF-SI-CBCT (right: 5.59 ± 1.66/left: 5.52 ± 1.61). Measurements between OPG and CBCT were not significantly different, except for MF-SI (right) (p = 0.042). While the overall difference between OPG and CBCT (MF-AP/MF-SI) measurements showed a significant association (p < 0.01) with the anatomic location (right/left), a significant association (p < 0.05) with biological sex was observed only for MF-AP. Based on this study's outcomes, digital OPG is an accurate modality to locate the MF based on anteroposterior (MF-AP) and superoinferior (MF-SI) measurements. This would be clinically beneficial for dental and oral surgeons to achieve the optimum IAN block anesthesia based on preoperative panoramic radiographs. Similarly, it would assist maxillofacial surgeons in planning mandibular orthognathic surgeries and ramus osteotomies without complications.

Unicystic ameloblastoma: Clinico-radiological and histopathological correlation with management

Unicystic ameloblastoma is a distinct entity of ameloblastoma characterized by slow growth and relatively locally aggressive behavior. This retrospective study aimed to assess the efficacy of different treatment modalities for unicystic Ameloblastoma, focusing on clinic-radiological and histopathological features. Data from patients diagnosed with unicystic ameloblastoma were retrospectively analyzed. Patients were categorized into luminal and intraluminal (Group A), and mural (Group B) variants based on the Ackermann classification, which has a significant influence on their biological behavior, treatment approaches, and prognosis. Patients in Group A underwent enucleation with chemical cauterization and peripheral ostectomy and Iodoform packing, whereas those in Group B were treated with resection and reconstruction. Postoperatively, the patients were subjected to radiographic assessments via digital orthopantomogram (OPG) at regular intervals. Because of the rarity of unicystic ameloblastoma, 17 patients were included in the study (Group A: 9 patients; Group B: 8 patients), utilizing a mean follow-up of 4.9 years (range: 1.4 - 11.8 years).The primary outcome measure was the absence of recurrence, which indicated treatment success. No patient in either group presented with recurrence during the follow-up period. This study provides evidence supporting the successful treatment of luminal and intraluminal variants of unicystic ameloblastoma in young individuals using a conservative approach. However, the more aggressive mural variant demonstrated favorable outcomes with radical treatment. These findings emphasize the importance of Ackermann classification in guiding treatment decisions for unicystic ameloblastoma and contribute valuable insights into optimizing therapeutic strategies based on clinicoradiologic and histopathological findings.

Prevalence of Impacted Third Molars Among Iraqi Patients Attending Al-Maghrib Specialized Dental Health Center in Relation to Age and Gender Using Panoramic Radiographs

Introduction: The most commonly impacted tooth is third molar. Aim: To investigate the prevalence of pattern of third molar impaction among patients attending Al-Maghrib specialized dental health center in Baghdad city. Materials and Methods: A cross-sectional analysis was conducted on digital orthopantomogram (OPGs) of high quality belonged to 519 patients referred to Al-Maghrib specialized dental health center in Baghdad city/Iraq between January2023 to June 2023. Data include age, gender and angulation type. Results: The age range was 20-70 years old. The prevalence of impacted third molar was 92%. The percentage of impacted lower third molar (51%) was higher than that of upper third molar (49%). Middle-aged patients (20-30, 31-40 years) recorded higher percentages of impaction than other age groups (31.7% and 32% respectively). Male gender revealed higher percentage (58%) of impaction than female gender (42%). Vertical and then mesioangular inclinations are the most prevalent types of lower third molar angulations (45% and 30% respectively). Conclusion: Higher prevalence of impaction in third molars was recorded in the current study that was more prevalent in the middle-aged patients with male predilection. The impaction was more common in the mandible than the maxilla. The most prevalent lower third molar angulation is vertical followed by mesioangular.

Deep learning methods for fully automated dental age estimation on orthopantomograms.

This study aimed to use all permanent teeth as the target and establish an automated dental age estimation method across all developmental stages of permanent teeth, accomplishing all the essential steps of tooth determination, tooth development staging, and dental age assessment. A three-step framework for automatically estimating dental age was developed for children aged 3 to 15. First, a YOLOv3 network was employed to complete the tasks of tooth localization and numbering on a digital orthopantomogram. Second, a novel network named SOS-Net was established for accurate tooth development staging based on a modified Demirjian method. Finally, the dental age assessment procedure was carried out through a single-group meta-analysis utilizing the statistical data derived from our reference dataset. The performance tests showed that the one-stage YOLOv3 detection network attained an overall mean average precision 50 of 97.50 for tooth determination. The proposed SOS-Net method achieved an average tooth development staging accuracy of 82.97% for a full dentition. The dental age assessment validation test yielded an MAE of 0.72years with a full dentition (excluding the third molars) as its input. The proposed automated framework enhances the dental age estimation process in a fast and standard manner, enabling the reference of any accessible population. The tooth development staging network can facilitate the precise identification of permanent teeth with abnormal growth, improving the effectiveness and comprehensiveness of dental diagnoses using pediatric orthopantomograms.

Artificial Intelligence: A Reliable Tool to Detect the Elongation of the Styloid Process.

Background Eagle's syndrome is characterized by the anomalous elongation of the styloid process. This condition is usually identified through the manual evaluation of orthopantomogram (OPG) images, which is time-consuming and can have interobserver variability. The application of Artificial intelligence (AI) in radiology is gaining importance and interest in recent years. The application of AI in detecting styloid process elongation is less explored, advocating for research in the same arena. Aim and objectives The study aimed to evaluate the accuracy of artificial intelligence in detecting styloid process elongation in digital OPGs and to compare the performance of the three different AI algorithms with that of the manual radiographic evaluation by the radiologist. Materials and methods A total of 400 digital OPGs were screened, and linear measurements of the styloid process length (ImageJ software (National Institute of Health, Maryland, USA)) were done for the identification of styloid process elongation by a single calibrated observer to finally include a processed image dataset including 169 images of the elongated styloid process and 200 images of the normal styloid process.A machine learning approach was used to detect the styloid process elongation using the three different AI models: logistic regression, neural network, and Naïve Bayes algorithms in Orange software (University of Ljubljana, Slovenia). Performance evaluation was done using the accuracy, sensitivity, specificity, precision, recall, F1 score, and AUC-ROC (area under the receiver operating characteristic) curve. Results Logistic regression and neural network algorithms depicted the highest accuracy of 100% with no false positives or false negatives, securing a score of 1.000 for all the metrics.However, the Naïve Bayes model demonstrated a fairly considerable accuracy, classifying 49 false positive images and 59 false negative images with an AUC (area under the curve) score of 78 %. Nevertheless, it performed better than random guessing. Conclusion Logistic regression and neural network algorithms accurately detected styloid process elongation similar to that of manual radiographic evaluation. The Naïve Bayes algorithm did not perform an accurate classification yet performed better than random guessing. AI holds a promising scope for its application in automatically detecting styloid process elongation in digital OPGs.

Comparative Evaluation of the Relationship between the Root-Tips of Maxillary Posterior Teeth and Floor of Maxillary Sinus using Digital Orthopantomogram in Chhattisgarh Individuals with Different Cephalic Indices

Background and Aims: Cephalic index has significant importance in the field of forensic science and variation in the cephalic index affects the facial dimensions and growth of the maxillary sinus in an individual. Knowledge of the anatomical relationship between maxillary posterior teeth and the floor of the maxillary sinus is very important for preoperative treatment planning in dentistry. The aim of the study is a comparative evaluation of the relationship and the distances between maxillary posterior teeth root tips and the floor of the maxillary sinus in different cephalic index subjects using a digital orthopantomogram. Materials and Methods: 210 subjects were categorized as Brachycephalic, Mesocephalic and Dolichocephalic according to their cephalic index. Orthopantomograms of these subjects were taken for assessment of vertical relationships between the maxillary posterior teeth and the floor of the maxillary sinus followed by distance measurement. Recorded data were statistically analyzed. Results: Significant difference in vertical distance was observed in all three cephalic groups in the case of 1st premolars, distobuccal roots of 1st molars and mesiobuccal roots of 2nd molars. Conclusion: The study concluded variation in the cephalic index affects the relationship and vertical distance between the maxillary sinus floor and the roots of maxillary posterior teeth.

Evaluation of Position and Symmetry of Mental Foramen on Digital Panoramic Radiographs: A Retrospective Study

Background: The mental foramen is an important anatomical landmark located on the anterolateral surface of the mandible, and it transfers the mental nerve and vessels. Knowledge of the position of the mental foramen is important both when administering regional anaesthesia and performing periapical surgery in the mental region of the mandible. Aim: The aim of this study was to determine the position and symmetry of the mental foramen on a digital orthopantomogram (OPG) among the Nalgonda population. Materials and Methods: A total of 400 digital OPGs taken by the Rotograph evo OPG machine of both genders were analysed retrospectively. The position of the mental foramen was recorded according to criteria given by Wei Cheong Ngeow and Yosuf Yuzawati. The symmetrical or asymmetrical position of the mental foramen was also recorded. Results: The most common position in the current study for the right side was position 4 (n = 202; 50.5%) followed by position 3 (n = 102; 25.5%), position 5 (n = 82; 20.5%), position 2 (n = 8; 2%), position 1 (n = 4; 1%) and the least common was position 6 (n = 2; 0.5%) and the most common position of mental foramen for left side was position 4 (200;50%) followed by position 3 (n = 132; 33%) , position 5 (n = 60; 15%), position 1 and 2 (n = 4; 1%) and the least common was position 6 (n = 0; 0%). The mental foramen was symmetrical in 250 patients (62.5%) and asymmetrical in 150 patients (37.5%). For the symmetrically placed mental foramina, the most common location was position 4 (n = 126; 50.4%) followed by position 3 (n = 76; 30.4%), position 5 (n = 42; 16.8), position 6 (n = 4; 1.6%), position 2 (n = 2; 0.8%), position 1 (n = 0; 0%). Conclusion: In the present study, it was found that the most common position of the mental foramen in the given population in both males and females was below the second premolar, followed by between two premolars. It was symmetrical in 62.5% of OPG’s. The current study was limited to evaluating the position and symmetry of the mental foramen relative to mandibular teeth in a small sample of the Nalgonda population in Telangana state using digital panoramic radiographs. In further studies, utilizing a larger sample size for evaluation of the mental foramen using advanced imaging modalities would be required for a more precise identification of the mental foramen.

Gender Determination by Orbital Aperture Morphometry in Nalgonda Population

Background: The orbital aperture morphometry can be considered as a valuable tool in gender determination since orbit possesses resistance to damage and disintegration processes. Aim and Objective: The aim and objective of this study was to evaluate the orbital aperture dimensions in nalgonda population and verify their relationship with gender. Materials and Methods: The present retrospective study was conducted to evaluate the morphometric dimensions of orbital aperture seen on digital orthopantomogram taken using PLANMECA digital machine and ROMEXIS software. The height and width of the orbits were measured using measuring tools in the accompanying software. Data were analyzed using IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY: IBM Corp. Results: Linear measurements such as orbital height and orbital width, were significantly greater in males than females in the Nalgonda population with P &lt; 0.001. The present study found 85.6% accuracy after subjecting the obtained value to discriminant function analysis. Conclusion: The discriminant scores greater than 1.5 value indicate the sample as male and scores lesser than 1.5 value indicate the sample as female. Therefore, orbital aperture measurements can be used for gender determination in human identification.

A Fractal Dimension Analysis to Evaluate the Change in the Alveolar Osseous Structure of Mandibular Incisors after Orthodontic Treatment: A Retrospective Study

Introduction: As bone traces tooth movement during orthodontic treatment, leading to biological response of the surrounding tissues of the teeth resulting in remodelling of the socket, favourable bone response is expected after incisor retraction. Orthodontic treatment causing changes in alveolar bone can be evaluated using Fractal dimension (FD) analysis, a mathematical method of information processing, where the input data is in the form of an image and generated information is displayed as numbers. Aim: To evaluate changes in the trabecular structure of alveolar bone after incisor retraction in the mandibular symphysis region in adult patients using fractal analysis. Materials and Methods: This retrospective study was conducted with digital Orthopantomogram (OPG) of 30 patients with class I and class II malocclusion with mandibular incisor protrusion treated with extraction and retraction of anterior teeth were taken with standard protocols at the three different periods, before orthodontic treatment (T0), before retraction (T1) and after retraction of anterior teeth (T2) included in the study. Regions of interest were located between the apices of mandibular incisors. FD was calculated using ImageJ software. Statistical Analysis was carried out by repeated Analysis of Variance (ANOVA) test and post-hoc test. Results: Total of 30 cases were selected, out of which 15 were males and 15 females with the mean age of 21±2 years. FD values of the alveolar bone of mandibular incisors at T0 were 1.470±0.09 which reduced to 1.390±0.09 at T1 and to 1.350±0.08 at T2. This overall changes in FD values were significant (p-value=0.001). Conclusion: Fractal dimension analysis demonstrate significant changes in bone trabeculation of the mandibular symphysis region before and after orthodontic treatment. It has valuable impact in the cases of fenestration, dehiscence’s, and osteoporosis.

Sex determination by morphometric analysis of mandibular parameters using digital orthopantomogram of patients in a Tertiary Care Hospital in Nepal

Sex determination by morphometric analysis of mandibular parameters using digital orthopantomogram of patients in a Tertiary Care Hospital in Nepal

An Analysis of the Viability of Nonvascular Iliac and Fibula Grafts in Mandibular Reconstruction in Patients with Circulatory Diseases: A Prospective Randomized Study.

Vascularized bone grafts are considered as the gold standard for mandibular reconstruction. However, there are certain limitations of them, such as they are contraindicated in patients with circulatory disturbances. Therefore, Non-vascular bone grafts become the viable option for reconstruction. Our study aims to prospectively compare the long-term viability of avascular iliac and fibula bone grafts in the reconstruction of mandibular defects. Objectives were to evaluate the difficulty in swallowing, mastication, speech problems, infection, wound dehiscence, restricted limb movement, and altered gait among the iliac and fibula group. A total of 14 patients, planned for the reconstruction of mandibular defects from 2016 to 2018 were randomly allocated into two groups; nonvascular iliac and fibula graft groups. Clinical assessment for improvement in function, esthetics, wound healing, pain, and donor site morbidity was done and was followed up for one year. Digital orthopantomogram was taken for radiographic evaluation for up to one year. Difficulty in swallowing, mastication, speech, infection, restricted limb movement, and altered gait was statistically significant and was seen more in the fibula group. Wound dehiscence with graft exposure was found in one subject. The overall success rate was 100% in the iliac group and 85.7% in the fibula group. Considering the long-term complications and success rate, the nonvascular iliac graft was found to be superior and can be used as an alternative to a nonvascular fibula graft for a defect length up to 7cm.

Mental foramen of mandible in South Kerala population - A digital radiographic study

To assess whether there is sexual dimorphism in the location of mental foramen from base of mandible in South Kerala population.A two-year retrospective study was conducted in 200 subjects [100 males and 100 females] using digital radiographs. The location of mental foramen mandible was assessed from digital orthopantomogram. The vertical distance was measured from the superior border of the mental foramen to the lower border of the mandible and the inferior border of the mental foramen to the lower border of the mandible. The obtained data statistically analyzed using SPSS software version 20. Descriptive statistics was analyzed. Independent t-test was done to determine the association between gender and different parameters. The level of significance set at p ≤ 0.05.The average value of the distance of lower border of mandible from the superior and inferior border of mental foramen is found to be significantly higher in males than females.The study revealed that there is sexual dimorphism in the location of mental foramen in South Kerala population.

Assessment of Morphological Variation of the Mandibular Condylar Process, Coronoid Process, and Sigmoid Notch in Temporomandibular Joints of Adult Population Using Digital Orthopantomogram Based on Age and Gender –A Cross-sectional Study

Introduction: Orthopantomogram, a form of radiography that uses X-ray technology and is used in the diagnosis and treatment planning in various fields of dentistry, has been found to be less expensive than other advanced imaging modalities such as computed tomography or magnetic resonance imaging. Objective: The aim of the study was to evaluate the shape of mandibular condylar process, coronoid process, and sigmoid notch in various age groups and among the gender. Methods: A study was conducted using 150 digital orthopantomograms of patients. The different shapes of condylar process, coronoid process, and sigmoid notch were traced in computer using Galileos software. Statistical analysis was performed on the data obtained. A Chi-square test was performed to evaluate the P-value which was ascertained to be significant if &lt;0.05. Results: The condylar shapes commonly observed among males and females were round, coronoid process shapes were triangular in shape and round, and sigmoid notches were wide. These variations in condylar process, coronoid process, and sigmoid notch are most commonly seen in the age group of 20–30 years. When compared between gender-wise and age-wise, there were no statistical significance differences found with these variations. Conclusion: In the present study, morphological variation in the shape of the condylar process, coronoid process, and sigmoid notch was observed among the adult population. Knowing these variations can help detect gender, age, and diagnoses of pathologies.

Morphometric Analysis of Mandibular Ramus for Sex Determination on Orthopantomogram

Mandible is the strongest and most dimorphic bone of skull which resists postmortem changes and plays an important role in sex determination. Skeletal characteristic differ in different population therefore need of population specific studies. The aim of present study was to determine sex by morphometric analysis of mandibular ramus. A cross sectionalstudy was performed in orthopantomogram of patients collected from Dental Department of Patan Hospital, Lalitpur, Nepal. One hundred and fifty digital orthopantomogram of patient fulfilling inclusion criteria were included in the study. Five different mandibular parameters (maximum ramus breadth, minimum ramus breadth, condylar height/maximum ramus height, projective height of ramus, and coronoid height) were measured bilaterally resulting in total 300 rami being assessed. Orthopantomogram were made with Planmeca ProMax classic 2D machine and all the measurements on digital radiograph were performed with Planmeca Romexis viewer software version 5.1.0.R. Discriminant function analysis was performed to find the most significant predictors for determining sex. All the measured mandibular parameters were statistically significantly higher in male than females (P<0.001). Condylar height was the most significant predictors for determining sex. The discriminate function equation was derived to determine sex with an overall accuracy of 84.0%. Morphometric analysis of mandibular ramus using digital orthopantomogram showed a high sexual dimorphism.

Study of mental foramen in patients coming to government dental hospital, Jamnagar

Introduction: The Mental foramen is one of two funnel-like openings located on the antero- lateral aspect of the body of the mandible. There are variations in it’s anatomical position in different individuals of different populations. Such variations can cause difficulty in diagnosis of peri-apical lesions. It may result in failure of regional anaesthesia during clinical and surgical procedures required to be administered in the mandibular and mental region. Aims And Objectives: This study was performed to determine the position and bilateral positional symmetry of mental foramen on a digital orthopantomogram (OPG) of the population visiting Government Dental Hospital, Jamnagar. The objective was to document the frequency of location of mental foramen in relation with several teeth in close possible proximity to the mental foramen on digital panoramic radiographs. Materials And Methods: The study was conducted in the Department of Oral Medicine and Radiology, Government Dental College and Hospital, Jamnagar. Radiographic study of mental foramen of 1270 participants was carried out by analysing their digital orthopantomographs. Mental foramina were analysed with respect to their positions and bilateral symmetry.

Estimation of dental age using Willems method and comparing it with Demirjian's method in 7-14-year-old children of Uttarakhand.

The aim of this comparative study was to estimate the dental age using Willems method by assessing the developmental stages of left seven permanent mandibular teeth in 7-14 years of age groups with the help of digital orthopantomogram and comparing it with Demirjian's method to conclude which method was more appropriate and better in Indian population of Uttarakhand region. A total of 100 digital orthopantomogram films of patients in the age group of 7-14 years was collected over the study period of 3 years from July 2014 to January 2017 and was equally distributed by convenience sampling. Group I included 50 boys and Group II included 50 girls aging 7-14 years of age (as permanent 7 teeth in the 3rd quadrant were to be assessed and scored according to the Demirjian's table, the 7-14 age group was selected). The date of birth of the subject was documented against their allocated identification number. Dental age according to Willem's method was calculated using Willem's table and Demirjian and Goldstein's table scores were used to calculate dental age by Demirjian's method. Willems method was more accurate and better than Demirjian's method as it showed less mean percentage error, i.e., 0.34% as compared to 15.94% obtained from Demirjian's method in Group II and 2.19% as compared to 8.05% obtained from Demirjian's method in Group I. The results suggested that Willems method of dental age estimation was an effective method of age estimation and was better and more accurate than Demirjian's method.

Mandibular parameters as a predictor of sex: A digital orthopantomogram study

Background: The determination of age and sex is required for forensic practice and medicolegal purposes. Because the mandible is typically recovered intact, it plays a crucial role in determining sex. Orthopantomogram X-rays can be used to thoroughly examine the mandible. The availability of a large number of antemortem orthopantomograms could be extremely beneficial in terms of evaluating and developing population-specific sex determination standards. Objectives: To evaluate the usefulness of the mandibular ramus in sex determination by evaluating linear and angular measurements of the mandibular ramus on digital panoramic radiographs. Methods: An analytical cross-sectional study was conducted on 216 digital orthopantomogram from March 2021 to June 2021 in Kantipur Dental College. A convenient sampling technique was used to collect the radiographs. Mandibular parameters were traced using Image J Software, and angular and linear parameters were calculated. Radiographs with high image quality and sharpness of patients with full permanent dentition, no radiographic evidence of trauma were included in the study. Descriptive analysis was done using IBM SPSS Statistics for Windows, version 20 (IBM Corp., Armonk, N.Y., USA). The measures were compared using an Independent t-test, and the results were subjected to discriminant function analysis. Results: The male’s vertical parameters were found to be greater than the female’s. The coronoid height was shown to be the most dimorphic using discriminant analysis. The overall accuracy of the mandibular parameters was 63.4%. Conclusion: Mandible can be used as an adjunct in sex determination.

Evaluation of Sexual Dimorphism of Inter Condylo-Coronoid Process Distance by Panoramic Radiography in South Indian Population

Background: Sexual dimorphism is a condition where the sexes of an equivalent species exhibit different characteristics beyond the differences in their sexual organs. Sexual identification is most significant in huge fatality accidents where the body is beyond recognition. Coronoid process of mandible is a triangular eminence, thin and flattened in size and shape. The Condylar process is the process of the mandible and it is thicker than the coronoid process. Identification of Gender characteristics is of forensic importance.&#x0D; Aim: To evaluate the sexual dimorphism of inter condylo-coronoid process distance by Panoramic radiographic study in the south Indian population.&#x0D; Materials and Methods: A total of 49 digital orthopantomogram collected from a private dental college in Chennai. The distance between the condylar and the coronoid process is measured on both sides of a digital orthopantomogram using adobe photoshop. The data was analyzed and observed using SPSS v23.0 and the standard deviation was calculated.&#x0D; Results: The mean of left and right distance of inter condylo-coronoid distance is 2.45cm and 2.52cm respectively. The standard deviation of left and right distance of inter condylo-coronoid distance is 0.32cm and 0.31cm respectively.&#x0D; Conclusion: From the results obtained, within the limitations of the study it can be concluded that there is no significant difference in the measure of distance between inter condyle-coronoid processes in terms of age and gender. Future studies should be conducted with large samples to get conclusive results using advance CBCT.

Comparison of Digital OPG and CBCT in Assessment of Risk Factors Associated with Inferior Nerve Injury during Mandibular Third Molar Surgery.

Background: Pre-operative radiographic assessment of the anatomical relationship between the roots of the mandibular third molar and the inferior alveolar nerve (IAN) is a must to minimize the risk of IAN injury during surgery. Objectives: To compare the radiographic signs of digital orthopantomogram (OPG) and cone-beam computed tomography (CBCT). An additional objective was to assess the cortex status between the mandibular canal and third molar on CBCT images in relation to the demographic characteristics, region (right or left side), and angulation of mandibular molar. Methodology: In this retrospective study, a total of 350 impacted mandibular third molars with a close relationship between the inferior alveolar canal (IAC) and impacted mandibular third molars on digital OPG were further referred for CBCT imaging for assessment of the position of the mandibular canal. The study was conducted between August 2018 and February 2020. Digital OPGs were evaluated for radiographic signs like interruption of the mandibular canal wall, darkening of the roots, diversion of the mandibular canal, and narrowing of the mandibular canal. The age and sex of patients, site of impacted third molar, Winter’s classification of mandibular third molar, position of IAC relative to impacted molar, and the radiographic markers of OPG were assessed for cortical integrity using CBCT. Chi square testing was applied to study the values of difference and binomial logistic regression was done to assess the factors associated with cortication. Statistical significance was set at p ≤ 0.05. Results: Among 350 patients, 207 (59.1%) were male and 143 (40.9%) were female with a mean age of 36.8 years. The most common OPG sign was interruption of white line, seen in 179 (51.1%) cases. In total, 246 cases (70.3%) showed an absence of canal cortication between the mandibular canal and the impacted third molar on CBCT images. Cortication was observed in all cases with a combination of panoramic signs which was statistically significant (p = 0.047). Cortication was observed in 85 (50.6%) cases where IAC was positioned on the buccal side, 11 (16.9%) in cases of inferiorly positioned IAC, and just 8 (7.6%) for cases of lingually positioned IAC which was statistically significant (p = 0.003). Statistically insignificant (p > 0.05) results were noted for cortex status in CBCT images with regards to the age, sex, site, and angulation of impacted third molars. Conclusion: CBCT imaging is highly recommended for those cases where diversion of the mandibular canal is observed on OPG and when the roots are present between canals.

Morphology of mandible - A two year digital radiographic study

Mandible is a unique single bone often recovered intact during mass disasters.To assess whether the specific morphological characteristics of mandible in males and females can be used as an aid for sex determination based on radiographs.A two-year retrospective study was conducted in 200 subjects [100 males and 100 females] using digital radiographs. Profile of chin and morphologic differences in the base of the mandible were assessed using digital lateral cephalogram. Mandibular ramus flexure was assessed from digital Orthopantomogram. The obtained data statistically analysed using SPSS software version 20. Descriptive statistics was analysed. Chi square test was done to determine the association between gender and different parameters. The level of significance set at p ≤ 0.05.There is a significant association between chin profile, base of mandible and mandibular ramus flexure with gender. Females have prominent chin compared to males. Males have undulating base of mandible while females have straight base of mandible. Mandibular ramus flexure in males seen at the level of occlusal plane while it is seen above the occlusal plane in females.There is a morphological difference in the mandible of the males and females.