Third molar eruption in dental panoramic radiographs as a feature for forensic age assessment - new reference data from a German population.

Forensic age assessment in the living can provide legal certainty when an individual's chronological age is unknown or when age-related information is questionable. An established method involves assessing the eruption of mandibular third molars through dental panoramic radiographs (PAN). In age assessment procedures, the respective findings are compared to reference data. The objective of this study was to generate new reference data in line with the required standards for mandibular third molar eruption within a German population. For this purpose, 605 PANs from 302 females and 303 males aged 15.04 to 25.99 years were examined. The PANs were acquired between 2013 and 2020, and the development of the mandibular third molars was rated independently by two experienced examiners using the Olze et al. staging scale from 2012. In case of disagreement in the assigned ratings, a consensus was reached through arbitration. While the mean, median and minimum ages were observed to increase with each stage of mandibular third molar eruption according to the Olze method, there was considerable overlap in the distribution of age between the stages. The minimum age for stage D, which corresponds to complete tooth eruption, was 16.1 years for females and 17.1 years for males. Thus, the completion of mandibular third molar eruption was found in both sexes before reaching the age of 18. In all individuals who had at least one tooth with completed eruption and who were younger than 17.4 years of age (n = 10), mineralization of the teeth in question was not complete. Based on our findings, the feature of assessing mandibular third molar eruption in PAN cannot be relied upon for determining age of majority.

New Perspectives in Third Molar Auto-Transplantation: Literature Review and a Case Report of Clinical, Financial and Forensic Implications.

Third molar extraction is the most common procedure in oral and maxillofacial surgery. Third molars are considered less functional than other teeth and are often extracted. Sometimes, they are also used for auto-transplantation for the benefit of oral rehabilitation. Since many biological factors are involved in this surgical approach, herein, we outline a review of the biological characteristics of medico-legal/forensic interest, in addition to presenting a successful clinical case. A scoping review of currently available research data (following the principles of PRISMA-ScR or the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) on third molar auto-transplantation was conducted by drawing upon the main databases (Scopus, PubMed, Google Scholar and LILACS) to evaluate biological and clinical characteristics possibly relatable to forensic issues. All the collected data were summarized and elaborated on for the purpose of this article. A patient underwent extraction of the right upper first molar and auto-transplantation of the unerupted ipsilateral third molar. Many biologic and clinical factors are involved in the success of this clinical procedure. Knowledge of third molar anatomy, of its development and viable surgical approaches are all essential elements; just as important are the treatment of the tooth before and after transplantation and the integrity of the periodontal ligament. Follow-up of the clinical case for 5 years made it possible to verify the stability of the procedure over time. Third molar auto-transplantation is feasible and cost-effective. However, the use of third molars as donor teeth in auto-transplantation may have medico-legal implications. The lack of official protocols and consistent evidence-based guidelines for operators still prevent such a procedure from becoming mainstream; therefore, it is viewed with suspicion by clinicians and patients, even though the biological factors herein detected point to a reasonably high degree of safety. The understanding of many specific biological and clinical factors involved in the stability of third molar auto-transplantation allows for a thorough understanding of the forensic implications relevant to clinical practice. Effective communication and information provision are therefore of utmost importance, in the interest of both patients and doctors.

Decision tree analysis for age estimation in living individuals: integrating cervical and dental radiographic evaluations within a South African population.

Age estimation in living individuals around the age of 18 years is medico-legally important in undocumented migrant cases and in countries like South Africa where many individuals are devoid of identification documents. Establishing whether an individual is younger than 18 years largely influences the legal procedure that should be followed in dealing with an undocumented individual. The aim of this study was to combine dental third molar and anterior inferior apophysis ossification data for purposes of age estimation, by applying a decision tree analysis. A sample comprising of 871 black South African individuals (n = 446 males, 425 = females) with ages ranging between 15 and 24 years was analyzed using panoramic and cephalometric radiographs. Variables related to the left upper and lower third molars and cervical vertebral ring apophysis ossification of C2, C3, and C4 vertebrae analyzed in previous studies were combined in a multifactorial approach. The data were analyzed using a pruned decision tree function for classification. Male and female groups were handled separately as a statistically significant difference was found between the sexes in the original studies. A test sample of 30 individuals was used to determine if this approach could be used with confidence in estimating age of living individuals. The outcomes obtained from the test sample indicated a close correlation between the actual ages (in years and months) and the predicted ages (in years only), demonstrating an average age difference of 0.47 years between the corresponding values. This method showed that the application of decision tree analysis using the combination of third molar and cervical vertebral development is usable and potentially valuable in this application.

A retrospective longitudinal assessment of artificial intelligence-assisted radiographic prediction of lower third molar eruption.

Prediction of lower third molar eruption is crucial for its timely extraction. Therefore, the primary aim of this study was to investigate the prediction of lower third molar eruption and its uprighting with the assistance of an artificial intelligence (AI) tool. The secondary aim was identifying the incidence of fully erupted lower third molars with hygienic cleansability. In total, 771 patients having two panoramic radiographs were recruited, where the first radiograph was acquired at 8-15 years of age (T1) and the second acquisition was between 16 and 23 years (T2). The predictive model for third molar eruption could not be obtained as few teeth reached full eruption. However, uprighting model at T2 showed that in cases with sufficient retromolar space, an initial angulation of < 32° predicted uprighting. Full eruption was observed for 13.9% of the teeth, and only 1.7% showed hygienic cleansability. The predictions model of third molar uprighting could act as a valuable aid for guiding a clinician with the decision-making process of extracting third molars which fail to erupt in an upright fashion. In addition, a low incidence of fully erupted molars with hygienic cleansability suggest that a clinician might opt for prophylactic extraction.

Dental age assessment in the living: a comparison of two common stage classifications for assessing radiographic visibility of the root canals in mandibular third molars.

After dentition is complete, degenerative tooth characteristics can be used for dental age assessment. Radiological assessment of the visibility of the root canals of the mandibular third molars in dental panoramic radiographs (DPRs) is known to be one such suitable feature. Essentially, two different stage classifications are available for evaluating the visibility of the root canals of mandibular third molars in the DPR. The aim of this study was to determine if one method outperforms the other. Therefore, the 2010 method of Olze et al. was directly compared to the 2017 method of Lucas et al. in the 2020 modification of Al Qattan et al. To this end, 233 DPRs from 116 females and 117 males aged 20.0 to 40.9 years were evaluated by three independent experienced examiners. In addition, one examiner ran two independent evaluations. Correlation between age and stage was investigated, and the inter- and intra-rater reliability was estimated for both methods. Correlation between age and stage was higher with the Olze method (Spearman rho 0.388 [95% CI 0.309, 0.462], males and 0.283 [95% CI 0.216, 0.357], females) than the Lucas method (0.212 [95% CI 0.141, 0.284], males and 0.265 [95% CI 0.193, 0.340], females). The intra-rater repeatability of the Olze method (Krippendorff's α = 0.576 [95% CI 0.508, 0.644], males and α = 0.592 [95% CI 0.523, 0.661], females) was greater than that for the Lucas method (intra-rater α = 0.422 [95% CI 0.382, 0.502], males and α = 0.516 [95% CI 0.523, 0.661], females). Inter-rater reproducibility was also greater for the Olze method (α = 0.542 [95% CI 0.463, 0.620], males and α = 0.533 [95% CI 0.451, 0.615], females) compared to the Lucas method (α = 0.374 [95% CI 0.304, 0.443], males and α = 0.432 [95% CI 0.359, 0.505], females). The method of Olze et al. was found to present marginal advantages to the Lucas et al. method across all examinations and may be a more appropriate method for application in future studies.

Preinterventional Third-Molar Assessment Using Robust Machine Learning.

Machine learning (ML) models, especially deep neural networks, are increasingly being used for the analysis of medical images and as a supporting tool for clinical decision-making. In this study, we propose an artificial intelligence system to facilitate dental decision-making for the removal of mandibular third molars (M3M) based on 2-dimensional orthopantograms and the risk assessment of such a procedure. A total of 4,516 panoramic radiographic images collected at the Center of Dental Medicine at the University of Zurich, Switzerland, were used for training the ML model. After image preparation and preprocessing, a spatially dependent U-Net was employed to detect and retrieve the region of the M3M and inferior alveolar nerve (IAN). Image patches identified to contain a M3M were automatically processed by a deep neural network for the classification of M3M superimposition over the IAN (task 1) and M3M root development (task 2). A control evaluation set of 120 images, collected from a different data source than the training data and labeled by 5 dental practitioners, was leveraged to reliably evaluate model performance. By 10-fold cross-validation, we achieved accuracy values of 0.94 and 0.93 for the M3M-IAN superimposition task and the M3M root development task, respectively, and accuracies of 0.9 and 0.87 when evaluated on the control data set, using a ResNet-101 trained in a semisupervised fashion. Matthew's correlation coefficient values of 0.82 and 0.75 for task 1 and task 2, evaluated on the control data set, indicate robust generalization of our model. Depending on the different label combinations of task 1 and task 2, we propose a diagnostic table that suggests whether additional imaging via 3-dimensional cone beam tomography is advisable. Ultimately, computer-aided decision-making tools benefit clinical practice by enabling efficient and risk-reduced decision-making and by supporting less experienced practitioners before the surgical removal of the M3M.

Assessment of relationships between condylar fracture pattern and mandibular third molar position by panoramic radiography and computed tomography: A retrospective comparative study.

BACKGROUND/AIM: Although previous studies have revealed the influence of the mandibular third molar (M3) on mandibular condylar fracture risk and that the presence of M3 could result in different incidences of condylar and angle fractures, there have been no analyses of the influence of M3 on fracture patterns. Moreover, evaluations of M3 position using panoramic radiography have shown insufficient accuracy. This study investigated the relationship between condylar fracture patterns and M3 position using panoramic radiography and computed tomography. MATERIALS AND METHODS: This retrospective study included 280 patients with unilateral mandibular condylar fractures and ipsilateral M3 admitted to West China Hospital of Stomatology between January 2016 and June 2022. Patient medical records, panoramic radiographs, and computed tomography images were collected. The vertical and horizontal positions of M3 were classified using the Pell and Gregory system. M3 angulation was defined as the angle between the long axis of M3 and the mandibular occlusal plane. Condylar fracture patterns were classified as intracapsular (Types A-C) or extracapsular (neck and base). Data were analyzed using McNemar-Bowker test, Pearson chi-squared test, and Fisher's exact test. RESULTS: Classification of M3 position differed significantly between panoramic radiography and computed tomography images (p < .05). There was a significant association between the mandibular condylar fracture pattern and M3 horizontal position on computed tomography (p < .05). Class I M3 position on computed tomography was associated with a higher incidence of intracapsular than extracapsular fractures, along with a higher incidence of Type B than base fractures; the opposite relationships were observed for Class II. No such association was identified on panoramic radiography. CONCLUSIONS: Mandibular condylar fracture patterns were presumably influenced by M3 horizontal position on computed tomography. The imaging modality affected the classification of M3 position and subsequent analyses. Computed tomography is recommended for future studies to improve accuracy and reliability.

A preliminary study on the assessment of pain using figures among patients administered with dental local anesthesia for mandibular third molar extraction.

The aim of this study was to clarify or determine any possible association between pain reports with a visual analogue scale (VAS) and a figures based scale. This research was a preliminary study aimed at developing a new pain scale without any verbal description. Healthy Japanese patients aged 20 to 39 years who received anesthetic injections for mandibular third molar extraction at our department were enrolled. Regarding pain from dental local anesthetic injections, we recorded figures selected by participants (among options of a circle, triangle, square, bar, and cross), and VAS scores. Overall, 29 men and 31 women participated in the study. Pain caused by local dental anesthesia tended to remind both men and women of the triangle among the suggested figures. Furthermore, patients who chose a cross also reported higher VAS scores than those who chose other figures. Acute pain caused by local dental anesthesia was associated with triangles, and patients who selected a cross were associated with higher VAS scores. The results of this study provide clinicians with important information for dental practice, and could prove useful in developing new pain scales.

Assessment of palatal mucosal thickness and location of the greater palatine foramen using cone-beam computed tomography: a retrospective study.

OBJECTIVES: This study aimed to measure the palatal mucosal thickness and examine the location of the greater palatine foramen using cone-beam computerized tomography (CBCT). METHODS: In this study, cone-beam computed tomography (CBCT) images of the maxillary posterior region of 120 subjects were evaluated. The palatal mucosal thickness (PMT), palatal width and depth, and location of the greater palatine foramen (GPF) were determined on CBCT. The differences in the palatal mucosal thickness according to gender and palatal width/palatal depth were analyzed. The location of the GPF related to the maxillary molars was noted. RESULTS: The mean palatal mucosal thicknesses from the canine to the second molar teeth were 3.66, 3.90, 4.06, 3.76, and 3.92 mm, respectively. The mean PMT at the second premolar was statistically thicker than at other regions (p < 0,001). There was no relationship between PMT and gender. However, the palatal depth and width of the males were greater than females. (p = 0.004 and p = 0.014, respectively) PMT in the low palatal vault group had statistically higher compared to the high palatal vault group. (p = 0.023) Greater palatine foramen was mostly observed between second and third molar teeth. (48%). CONCLUSIONS: According to our results, first and second premolar regions can be preferable in soft tissue grafting procedures for safe and successful treatment outcomes. The measurement of the thickness of the palatal mucosa and the evaluation of the greater palatine foramen location before the surgical procedures are essential steps to harvest from the ideal donor site and to achieve optimal surgical outcomes.

A modified triangular flap suture method used for inferior third molar extraction: A three-arm randomized clinical trial for the assessment of quality of life.

BACKGROUND: The purpose of this study is to explore whether decreasing the number of sutures can improve the quality of life after inferior third molar extraction. MATERIAL AND METHODS: This study used a three-arm randomized design that included 90 individuals. Patients were randomized and divided into three groups-the airtight suture group (traditional), the buccal drainage group, and the no-suture group. Postoperative measurements, including treatment time, visual analog scale, questionnaire on postoperative patient quality of life, and details about trismus, swelling, dry socket, and other postoperative complications were obtained twice and the mean values were recorded. To verify the normal distribution of the data, the Shapiro-Wilk test was performed. The statistical differences were evaluated using the one-way ANOVA and the Kruskal-Wallis test with Bonferroni post-hoc correction. RESULTS: The buccal drainage group showed a significant decrease in postoperative pain and better speech ability than the no-suture group on the 3st day, with a mean of 1.3 and 0.7 (P < 0.05). The airtight suture group also showed similar eating and speech ability, which was better than the no-suture group, with a mean of 0.6 and 0.7 (P < 0.05). However, no significant improvements were noted on the 1st and 7th days. The surgical treatment time, postoperative social isolation, sleep impairment, physical appearance, trismus, and swelling showed no statistical difference between the three groups at all measured times (P > 0.05). CONCLUSIONS: Based on the above findings, the triangular flap without a buccal suture may be superior to the traditional group and no-suture group in less pain, and better postoperative patient satisfaction in the first 3 days and may be a simple and viable option in clinical practice.

Assessment of Dry Socket after Mandibular Third Molar Surgery Using Platelet-Rich Fibrin - A Prospective Clinical Study.

OBJECTIVE:  To determine the efficacy of Platelet-Rich Fibrin (PRF) in preventing Dry Socket (DS) after mandibular third molar surgery in comparison with the control group. STUDY DESIGN: Experimental study. Place and Duration of the Study: Oral and Maxillofacial Surgery Department, Dental Section, Faisalabad Medical University, Faisalabad, Pakistan, from July 2019 to June 2021. METHODOLOGY: Patients aged 18-35 years with good oral hygiene, and requiring surgical extraction of their mandibular third molar were included in the study. Those with periodontal disease, pregnant or nursing women, smokers, or allergic to the agents that were recommended for use before and after surgery, were excluded. Patients presenting for surgical removal of the mandibular third molar and meeting the inclusion criteria were enrolled and randomly divided into 2 groups. Standard protocol for tooth removal was followed in both groups. Group1 (study group) received PRF and group 2 (control group) did not receive PRF. RESULTS: A total of 170 consecutive patients (85/group) were randomly selected and allocated to the study group and control group. The mean age in the study group was 24.28±3.7 years while the mean age in the control group was 24.14±3.64 years. Out of them, 51.2% (n=87) were males and 48.8% (n=83) were females with a M: F of 1:1.05. On the 3rd postoperative day, DS frequency in the study group was 2.4% (n=2) and 18.8% (n=16) in the control group (p=0.0001), which reduced to 01 and 05 respectively on 7th day (p=0.096). CONCLUSION: PRF administration was effective in preventing DS on the third postoperative day in mandibular third molar surgery, with statistically significant results. However, on postoperative day 7, the results were not statistically significant. KEY WORDS: Third molar, Tooth extraction, Dry socket, PRF.

Positional assessment of lower third molar and mandibular canal using explainable artificial intelligence.

OBJECTIVE: The aim of this study is to automatically assess the positional relationship between lower third molars (M3i) and the mandibular canal (MC) based on the panoramic radiograph(s) (PR(s)). MATERIAL AND METHODS: A total of 1444 M3s were manually annotated and labeled on 863 PRs as a reference. A deep-learning approach, based on MobileNet-V2 combination with a skeletonization algorithm and a signed distance method, was trained and validated on 733 PRs with 1227 M3s to classify the positional relationship between M3i and MC into three categories. Subsequently, the trained algorithm was applied to a test set consisting of 130 PRs (217 M3s). Accuracy, precision, sensitivity, specificity, negative predictive value, and F1-score were calculated. RESULTS: The proposed method achieved a weighted accuracy of 0.951, precision of 0.943, sensitivity of 0.941, specificity of 0.800, negative predictive value of 0.865 and an F1-score of 0.938. CONCLUSION: AI-enhanced assessment of PRs can objectively, accurately, and reproducibly determine the positional relationship between M3i and MC. CLINICAL SIGNIFICANCE: The use of such an explainable AI system can assist clinicians in the intuitive positional assessment of lower third molars and mandibular canals. Further research is required to automatically assess the risk of alveolar nerve injury on panoramic radiographs.

Assessment of Difficulty in Mandibular Third Molar Surgery by Lambade-Dawane-Mali's Index.

PURPOSE: The evaluation of mandibular third molar (M3) difficulty is extremely important. This study aims to measure the association between preoperative Lambade-Dawane-Mali's (LDM) M3 difficulty index and postoperative assessment of difficulty score. MATERIAL AND METHODS: This prospective cohort study included patients with impacted M3 reported to the Department of OMS, RRK Dental College, Akola, from 2017 to 2022. The preoperative surgical difficulty was estimated using the predictor, LDM index with scores, easy (15-25), moderate (25-30), and difficult (>30). The postoperative surgical difficulty was analyzed with the primary outcome variable, total time intervention measured from the beginning of incision to the final suturing, wherein extraction was classified as easy if time (<15 minutes), moderate (15-30 minutes), and difficult (>30 minutes). The secondary outcome variable, Modified Parant's Scale (MPS), defines four levels of difficulty required for extraction of M3: Easy I (forceps extraction), Easy II (requiring osteotomy), Difficult III (coronal sectioning), and Difficult IV (complex extraction). Data were analyzed using agreement between LDM difficulty with three established criteria (time, MPS, Pederson index) and were assessed with Cohen's Kappa statistics. McNemar's test for paired data was used to assess concordance between two criteria of evaluation with a P-value <.05 was considered statistically significant. RESULTS: The study sample included 1000 patients with a mean age of 26.7 ± 7.6 years and 456 (45.6%) females. Those assessed preoperatively with LDM to be difficult and easy outcomes were found upon postoperative assessment with MPS to be 99% and 99% correct, respectively. Inter-criteria agreement and Kappa statistics suggested a positive Kappa value (κ) and statistically significant agreement between the LDM index with perioperative time (κ = 0.8930), MPS (κ = 0.6488), and Pederson index (κ = 0.4920) at P-value 0.0001. Pair-wise comparisons of LDM criteria with perioperative time, MPS, and Pederson scale were assessed by McNemar's test, which evaluated concordance between the two criteria. CONCLUSION: Postoperative evaluation of surgical difficulty in M3 extraction was strongly correlated with preoperative variables in the LDM difficulty-scoring index. Preoperative evaluation helps in anticipating the difficulty, planning surgical management, and scheduling time more optimally.

Third molar eruption in orthopantomograms as a feature for forensic age assessment-a comparison study of different classification systems.

Evaluation of third molar eruption represents an established method for age assessment of living individuals. Different classification systems are available for the radiological assessment of third molar eruption. The aim of this study was to identify the most accurate and reliable classification system for the mandibular third molar eruption on orthopantomograms (OPG). We compared the method of Olze et al. (2012) with the method of Willmot et al. (2018) and a newly derived classification system using OPGs from 211 individuals aged 15-25 years. The assessments were performed by three experienced examiners. One examiner evaluated all radiographs twice. The correlation between age and stage was investigated and the inter- and intra-rater reliability was estimated for all three methods. Correlation between stage and age was similar between classification systems, although higher in the data from males (Spearman's rho ranging from 0.568 to 0.583) than from females (0.440 to 0.446). Inter- and intra-rater reliability measures were similar across methods and invariant on sex, with overlapping confidence intervals, although the highest point estimates for both intra- and inter-rater reliability were for the method by Olze et al. with Krippendorf's alpha values of 0.904 (95% confidence interval 0.854, 0.954) and 0.797 (95% confidence interval 0.744, 0.850). It was concluded that the method of Olze et al. from 2012 is a reliable method for practical application and future studies.

Third molar maturity index (I3M) assessment according to different geographical zones: a large multi-ethnic study sample.

Identification of living undocumented individuals highlights the need for accurate, precise, and reproducible age estimation methods, especially in those cases involving minors. However, when their country of origin is unknown, or it can be only roughly estimated, it is extremely difficult to apply assessment policies, procedures, and practices that are accurate and child-sensitive. The main aim of this research is to optimize the correct classification of adults and minors by establishing new cut-off values for four different continents (Africa, America, Asia, and Europe). For this purpose, a vast sample of 10,701 orthopantomographs (OPTs) from four continents was evaluated. For determination and subsequent validation of the new third molar maturity index (I3M) cut-off values by world regions, a cross-validation by holdout method was used and contingency tables (confusion matrices) were generated. The lower third molar maturity indexes, from both left and right side (I3ML and I3MR) and the combination of both sides (I3ML_I3MR) were calculated. The new cut-off values, that aim to differentiate between a minor and an adult, with more than 74.00% accuracy for all populations were as follows (I3ML; I3MR; I3ML_I3MR, respectively): Africa = (0.10; 0.10; 0.10), America = (0.10; 0.09; 0.09), Asia = (0.15; 0.17; 0.14), and Europe = (0.09; 0.09; 0.09). The higher sensitivity (Se) was detected for the I3ML for male African people (91%) and the higher specificity (Sp) of all the parameters (I3ML; I3MR; I3ML_I3MR) for Europeans both male and female (> 91%). The original cut-off value (0.08) is still useful, especially in discriminating individuals younger than 18 years old which is the goal of the forensic methods used for justice.

Assessment of mandibular retromolar space in adults with regard to third molar eruption status.

OBJECTIVE: The aim of this study was to compare the difference in length and width of the mandibular retromolar space (RMS) stratified by the different eruption and impaction statuses of the third molars in patients with skeletal Class I malocclusion. MATERIALS AND METHODS: The right mandibular RMS in 186 adult patients categorized according to the different statuses of the third molar was analyzed by using cone-beam computed tomography (CBCT). The shortest distances between the inner lingual cortex of the mandibular body and second molar root were measured parallel to the posterior occlusal line (POL) at depths of 2, 4, 6, 8, and 10 mm (mandibular retromolar space length in root level, RLin2,4,6,8,10) on the axial slices with the cementoenamel junction (CEJ) as the reference level. The width of the RMS and second molar root was measured vertical to the POL at the terminal point of the molar distalization at depths of 2, 4, 6, 8, and 10 mm (width of the mandibular retromolar space, BW2,4,6,8,10/ width of the second molar distal root, TW2,4,6,8,10) from the CEJ. RESULTS: RL in different measurement planes was 2.72 ± 2.22 ~ 3.74 ± 2.26 for Group A, 5.27 ± 1.68 ~ 9.10 ± 2.04 for Group B, 1.94 ± 2.34 ~ 5.71 ± 4.37 for Group C, 1.83 ± 2.95 ~ 5.05 ± 4.24 for Group D, and 5.93 ± 3.97 ~ 10.52 ± 2.16 for Group E. The BW measurement results for A ~ E group were 9.71 ± 1.41 ~ 10.51 ± 1.81, 9.83 ± 1.39 ~ 12.55 ± 2.11, 9.96 ± 1.21 ~ 12.17 ± 1.62, 9.82 ± 1.47 ~ 12.28 ± 2.77, and 10.02 ± 1.20 ~ 12.75 ± 0.82, respectively. There was no significant difference between men and women in any measurements (P > 0.05). Patients with normal third molars erupted and those vertically impacted possessed larger RMS lengths than those in which the third molars were missing, horizontally impacted or mesially impacted (P < 0.05). In each measurement plane, TW was significantly smaller than BW (P < 0.05). CONCLUSIONS: Sex had no effect on the length or width of the mandibular RMS. Different statuses of third molars can also differentially affect the mandibular RMS. The mandibular RMS width is not a limit for mandibular molar distalization. CLINICAL RELEVANCE: When considering the distalization of mandibular molars, more attention should be directed to the lingual cortex of the mandible, and CBCT scans are recommended for patients who require significant mandibular molar distalization. The mandible buccal shelf and retromolar area maybe a safe zone to insert the miniscrew for molar distalization.

Assessment of Panoramic Radiographic Variables as Predictors of Inferior Alveolar Nerve Injury During Third Molar Extraction

ABSTRACT Objective: To assess the role of radiological predictive markers on orthopantomogram for inferior alveolar nerve (IAN) injury related to the removal of mandibular third molar surgery and the occurrence of post-operative IAN paresthesia. Material and Methods: This prospective observational study was conducted on 60 patients (aged 17-35 years) indicated for extraction and showed one or more of the seven previously known panoramic radiographic risk signs of IAN injury. Variables such as age, sex, tooth angulation, and relationship with the inferior alveolar canal (IAC) were assessed to see their outcome on IAN injury. Data analysis is presented through tables and descriptive methods. Results: Among patients, 26 were male and 34 were female, with a mean age of 26.17 years. Out of seven radiological predictive markers, only six were found in this study, whereas one marker, viz. interruption of white line of the canal was not found. After surgical removal of the lower third molar, only two patients with radiographic signs showing the deflection of roots and darkening of roots continued with sensory deficit 5 weeks post-operatively. Conclusion: The risk of inferior alveolar nerve injury during lower third molar surgery is very low, even in patients with radiological predictive markers.

Risk assessment of inferior alveolar nerve injury after wisdom tooth removal using 3D AI-driven models: A within-patient study.

OBJECTIVE: To compare a three-dimensional (3D) artificial intelligence (AI)- driven model with panoramic radiography (PANO) and cone-beam computed tomography (CBCT) in assessing the risk of inferior alveolar nerve (IAN) injury after mandibular wisdom tooth (M3M) removal through a within-patient controlled trial. METHODS: From a database of 6,010 patients undergoing M3M surgery, 25 patients met the inclusion criteria of bilateral M3M removal with postoperative unilateral IAN injury. In this within-patient controlled trial, preoperative PANO and CBCT images were available, while 3D-AI models of the mandibular canal and teeth were generated from the CBCT images using the Virtual Patient Creator AI platform (Relu BV, Leuven, Belgium). Five examiners, who were blinded to surgical outcomes, assessed the imaging modalities and assigned scores indicating the risk level of IAN injury (high, medium, or low risk). Sensitivity, specificity, and area under receiver operating curve (AUC) for IAN risk assessment were calculated for each imaging modality. RESULTS: For IAN injury risk assessment after M3M removal, sensitivity was 0.87 for 3D-AI, 0.89 for CBCT versus 0.73 for PANO. Furthermore, the AUC and specificity values were 0.63 and 0.39 for 3D-AI, 0.58 and 0.28 for CBCT, and 0.57 and 0.41 for PANO, respectively. There was no statistically significant difference (p>0.05) among the imaging modalities for any diagnostic parameters. CONCLUSION: This within-patient controlled trial study revealed that risk assessment for IAN injury after M3M removal was rather similar for 3D-AI, PANO, and CBCT, with a sensitivity for injury prediction reaching up to 0.87 for 3D-AI and 0.89 for CBCT. CLINICAL SIGNIFICANCE: This within-patient trial is pioneering in exploring the application of 3D AI-driven models for assessing IAN injury risk after M3M removal. The present results indicate that AI-powered 3D models based on CBCT might facilitate IAN risk assessment of M3M removal.

Assessment of Relationship between Hemodynamic Changes and Anxiety in Patients During Lower Third Molar Surgery.

OBJECTIVE: To investigate the relationship between anxiety and hemodynamic changes in patients who have undergone impacted third molar surgery under local anaesthesia. STUDY DESIGN: Observational clinical study. PLACE AND DURATION OF STUDY: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gazi University, Ankara, Turkey, from January 2018 to December 2019. METHODOLOGY: Normotensive patients aged over 18 years, not using antidepressant medicine and ASA I included. A total of 83 patients were monitored and operated on for impacted third molar surgery. Blood pressure, pulse, and oxygen saturation values of the patients were noted at eight different stages during the surgery. Only the mesioangular impacted lower third molars of the patients were removed by a surgical operation. STAI forms were given before the operation. RESULTS: There is a significant difference between values of blood pressure, pulse, and oxygen saturation and gender (p<0.05). However, there was found to be an increased blood pressure in male patients while an increase in pulse and oxygen saturation was observed in female patients (p<0.05). CONCLUSION: Male patients were more concerned than female patients by having higher blood pressure which may cause longer postoperative bleeding. KEY WORDS: Anxiety, Impacted third molars, Dental surgery, Hemodynamic changes.

Furcation-involved molar teeth - part 1: prevalence, classification and assessment.

Furcation-involved molars are a common presentation in general dental practice. Teeth with increasing degrees of furcation involvement are at a higher risk of requiring extraction. The assessment and management of these teeth may be complicated by difficulties in accessing the furcation for both the clinician and patient. However, with appropriate supportive therapy, these teeth have been shown to have acceptable survival rates. This first article reviews and discusses the classification, assessment and the non-surgical management of furcation-involved molar teeth. An improved understanding of how to appropriately manage these teeth can result in improved outcomes for patients.