Endoscopically-assisted extraction of broken roots or fragments within the mandibular canal: a retrospective case series study.

PURPOSE: To assess the impact of endoscope-assisted fractured roots or fragments extraction within the mandibular canal, along with quantitative sensory testing (QST) alterations in the inferior alveolar nerve (IAN). METHODS: Six patients with lower lip numbness following mandibular third molar extraction were selected. All patients had broken roots or fragments within the mandibular canal that were extracted under real-time endoscopic assistance. Follow-up assessments were conducted on postoperative days 1, 7, and 35, including a standardized QST of the lower lip skin. RESULTS: The average surgical duration was 32.5 min, with the IAN exposed in all cases. Two of the patient exhibited complete recovery of lower lip numbness, three experienced symptom improvement, and one patient remained unaffected 35 days after the surgery. Preoperative QST results showed that the mechanical detection and pain thresholds on the affected side were significantly higher than those on the healthy side, but improved significantly by postoperative day 7 in five patients, and returned to baseline in two patients on day 35. There were no significant differences in the remaining QST parameters. CONCLUSIONS: All endoscopic surgical procedures were successfully completed without any additional postoperative complications. There were no cases of deterioration of IAN injury, and lower lip numbness recovered in the majority of cases. Endoscopy allowed direct visualization and examination of the affected nerve, facilitating a comprehensive analysis of the IAN.

Prevalence and patterns of third molar impaction among Ethiopians in Addis Ababa: a retrospective pilot study.

Tooth impaction is a condition in which a tooth does not reach its normal position and is often observed in the third mandibular molar due to inadequate space. This study aimed to investigate the prevalence and configuration of the impacted third molars with an emphasis on angular orientations in a sample of the Ethiopian population. This cross-sectional study included a retrospective analysis of 291 patient records and orthopantomography data from the archives of a private dental clinic in Addis Ababa, during the study period from December 2020 to November 2022. Demographic details and data on the position and level of the impacted third molars were evaluated using the Winter classification. Data were analyzed for frequency distribution. The prevalence of impacted third molars was 22% (n = 64), with a greater incidence on the right side (60.9%) and a higher frequency in the mandible (67.2%). Vertical angulation (32.8%), followed by mesioangular angulation (31.2%), was the most common impaction pattern. The results highlight the need for improved treatment protocols for third molar impaction, emphasizing the prevalence in the mandible and the importance of addressing vertical impaction. Regular dental check-ups are essential for assessing third molar impaction and planning appropriate management. These data can inform policymaking and treatment considerations for impacted third molars in the Ethiopian population.

The Showcases of Dental History - A Time Machine in Miniature at the University of Puerto Rico: Part I.

The evolution of 20-year-old dental museum-like showcases located in the lobby and the main hallway of the School of Dental Medicine, Puerto Rico (PR) are described along with important professionals who impacted on this development.

Long-term follow-up after the treatment of impacted canines in the maxilla causing severe root resorption of the lateral incisors: two case reports.

BACKGROUND: Root resorption of adjacent teeth due to impacted canines is common, and orthodontic treatment often leads to secondary resorption or even loss of adjacent roots. Clinical reports of long-term stability after treatment are rare. CASE PRESENTATION: This study reports two cases of maxillary impacted canines resulting in severe root resorption of the adjacent lateral incisors. Surgical exposure, orthodontic retraction, and alignment of the impacted canines were successful in both cases, and the resorbed lateral incisors were stable with no significant loosening and normal pulp vitality after treatment and at the 5- and 10-year follow-up appointments. CONCLUSIONS: Light orthodontic force may be used to move adjacent teeth with root resorption due to tooth obstruction. The path and direction in which the teeth are moved must be specifically designed so that the adjacent roots are not resorbed and so long-term stability can be achieved.

Implant Placement When an Impacted Tooth and Supernumerary Teeth Are Present in the Maxilla.

The presence of impacted and/or supernumerary teeth in the maxillary anterior region can cause complications when attempting to perform restorations with implants. Extracting these structures can lead to adverse issues related to the adjacent dentition and require osseous grafting to provide a base to house the planned implant, but such an approach increases treatment time and cost. In this case report, a patient presented with an impacted permanent canine oriented on the horizontal plane with several supernumerary teeth coronal to the impacted canine. CBCT analysis revealed a very thin buccal plate over the impacted supernumerary teeth. The proposed treatment followed the principles of partial extraction therapy (PET) whereby the impacted structures were treated like bone, and implants were placed in contact with them or through them to achieve the desired osseointegration and provide long-term survival of the restored implants.

[Clinical observation of minimally invasive extraction of lower third molar by retaining the buccal bone plate].

PURPOSE: To explore the effect of extracting the completely impacted teeth by minimally invasive surgery with preserving the buccal bone plate. METHODS: Eighty-six cases were selected and randomly divided into 2 groups. In the experimental group, a fenestration was made with a ball drill to expose the buccal and lingual margin of crown, and the buccal bone plate was preserved. T-shaped crown cuttings were performed, minimally invasive extraction was conducted.In the control group, the distal and buccal bone plates were removed with a ball drill, the distal and buccal crowns were exposed, and T-shaped crown was cut. The other procedures were the same. The degree of swelling, restricted mouth opening and VAS pain score after operation were observed, the levels of C-reactive protein and anti-hemolytic streptoglobulin were detected by laboratory tests, and the periodontal probing depth(PD), bleeding index (BI), and clinical attachment loss(CAL) of the adjacent second molar were examined 1 month after surgery. SPSS 25.0 software package was used for data analysis. RESULTS: The swelling degree of the two groups was significantly relieved in the experimental group than in the control group (P＜0.05), and there was no significant difference in the degree of mouth opening limitation and pain (P＞0.05). The level of C-reactive protein in the control group was significantly higher than that in the observation group (P＜0.05). There was no significantly difference in the level of anti-hemolytic streptococcus between the 2 groups (P＞0.05). One month after operation, the PD and CAL in the control group were significantly higher than those in the experimental group(P＜0.05). There was no significant difference between the 2 groups in BI(P＞0.05). CONCLUSIONS: The patients who preserve the buccal bone plate by minimally invasive extraction of impacted mandibular teeth have less reaction and better wound healing.

[Evaluation of the effect of MTF-S on the removal of impacted mandibular wisdom teeth with complete or partial crown impaction].

PURPOSE: To evaluation the effect of modified triangular flap-secondary healing (MTF-S) on the treatment of mandibular impacted wisdom teeth with full or partial bone impaction. METHODS: A total of 207 patients with mandibular impacted wisdom teeth were selected in Shaoxing Stomatological Hospital from June 2022 to June 2023. Among them, 86 patients had completely impacted wisdom teeth (group A), and 121 patients had partially impacted wisdom teeth (group B). All patients had bilateral impacted wisdom teeth. One of the wisdom teeth was removed first and was sutured with triangular flap-primary healing (TF-P). The other wisdom tooth was removed two weeks later and was sutured with MTF-S. Patients in groups A and B were divided into two subgroups based on suture methods, with TF-P used for group A1 and B1, and MTF-S used for groups A2 and B2. Perioperative indicators, including surgical time, root loss rate, and completeness of extraction sockets were recorded; Postoperative complications of four groups, including pain, swelling, and limited mouth opening were compared. SPSS 22.0 software package was used for statistical analysis. RESULTS: The surgical time of group A1, A2, B1 and B2 was (17.69±3.28), (18.22±3.06), (12.37±3.72) and (12.64±4.13) minutes, respectively. The surgical time of group A1 and A2 was significantly longer than that of group B1 and B2 (P＜0.05). Seven days after surgery, the VAS scores of group A1, A2, B1 and B2 were (1.17±0.34), (0.93±0.29), (0.48±0.15) and (0.76±0.21), respectively. The VAS scores of group B1 and B2 were lower than those of group A1 and A2, and group A2 was lower than group A1 and B2 was higher than group B1 group(P＜0.05). On the 1st day, 3rd day, and 7th day after surgery, the swelling degree in group A1 was greater than that in group B1, and the swelling degree in group B1 was greater than that in group A2 and B2(P＜0.05); while the limitation of mouth opening mouth in group A2 and B2 was lower than that in group A1 and B1, and the limitation of opening mouth in group B2 was lower than that in group A2(P＜0.05). CONCLUSIONS: Compared with partially impacted wisdom teeth, the extraction of completely impacted wisdom teeth has a longer surgical time. For completely impacted wisdom teeth, MTF-S is beneficial for reducing postoperative pain, swelling and mouth opening limitations. For partially impacted wisdom teeth, MTF-S is beneficial for reducing postoperative swelling and mouth opening limitations, but the effect is not significant in reducing patient pain.

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.

Prevalence of impacted third molars: a radiographic study among a North African population.

INTRODUCTION: Third molars are the most commonly concerned teeth with the impaction. Impacted third molar (ITM) can be associated to various clinical pathologies Aim: To determine the prevalence of ITM, its pattern and associated affections in Tunisian patients. METHODS: The study reviewed panoramic radiographs of patients consulting the Fattouma Bourguiba University Hospital, Monastir (Tunisia). Orthopantomograms were analyzed to define the prevalence of ITM; its angulation, depth and relation with the anterior border of mandibular ramus. Associated pathologies were also assessed. RESULTS: Seven hundred and thirty patients were included (286 men and 444 women). The age ranged from 19 to 89 years. Half of the patients (50.3%) showed at least one ITM. The total number of ITM was 881 with a statistical difference between arches (respectively 34.3% and 65.7% in the maxilla and in the mandible). The most common number of ITM was two (35.4%). Level C of impaction was observed more frequently in the maxilla and level A in the mandible. The most common angulation was the vertical one for both arches. Seventy six percent of ITM were presented with class II in relation with the anterior border of mandibular ramus. There was no significant difference in the frequency of impaction between gender and sides. The number of ITM associated with pathological conditions was 199 (22.6%). The most frequently observed pathology was the distal caries on the second molars (11.7%) followed by the caries of the third molars (5.2%). CONCLUSION: The prevalence of ITM among Tunisian patients was high.

Combining public datasets for automated tooth assessment in panoramic radiographs.

OBJECTIVE: Panoramic radiographs (PRs) provide a comprehensive view of the oral and maxillofacial region and are used routinely to assess dental and osseous pathologies. Artificial intelligence (AI) can be used to improve the diagnostic accuracy of PRs compared to bitewings and periapical radiographs. This study aimed to evaluate the advantages and challenges of using publicly available datasets in dental AI research, focusing on solving the novel task of predicting tooth segmentations, FDI numbers, and tooth diagnoses, simultaneously. MATERIALS AND METHODS: Datasets from the OdontoAI platform (tooth instance segmentations) and the DENTEX challenge (tooth bounding boxes with associated diagnoses) were combined to develop a two-stage AI model. The first stage implemented tooth instance segmentation with FDI numbering and extracted regions of interest around each tooth segmentation, whereafter the second stage implemented multi-label classification to detect dental caries, impacted teeth, and periapical lesions in PRs. The performance of the automated tooth segmentation algorithm was evaluated using a free-response receiver-operating-characteristics (FROC) curve and mean average precision (mAP) metrics. The diagnostic accuracy of detection and classification of dental pathology was evaluated with ROC curves and F1 and AUC metrics. RESULTS: The two-stage AI model achieved high accuracy in tooth segmentations with a FROC score of 0.988 and a mAP of 0.848. High accuracy was also achieved in the diagnostic classification of impacted teeth (F1 = 0.901, AUC = 0.996), whereas moderate accuracy was achieved in the diagnostic classification of deep caries (F1 = 0.683, AUC = 0.960), early caries (F1 = 0.662, AUC = 0.881), and periapical lesions (F1 = 0.603, AUC = 0.974). The model's performance correlated positively with the quality of annotations in the used public datasets. Selected samples from the DENTEX dataset revealed cases of missing (false-negative) and incorrect (false-positive) diagnoses, which negatively influenced the performance of the AI model. CONCLUSIONS: The use and pooling of public datasets in dental AI research can significantly accelerate the development of new AI models and enable fast exploration of novel tasks. However, standardized quality assurance is essential before using the datasets to ensure reliable outcomes and limit potential biases.

Minimally invasive surgical removal of bilateral impacted mandibular supernumerary teeth using 3D surgical guide template: a case report.

Impacted supernumerary teeth are defined as the presence of one or more teeth in a patient's upper and lower jaws in addition to the normal number of teeth in the dental arch. It has an incidence rate of approximately 1%-14% and more frequently occurs in males than females, may be single or multiple, unilateral or bilateral, erupted or impacted. In this article, we describe the case of a patient with two supernumerary teeth between the roots of the mandibular second premolar and the first molar, which influenced the effectiveness of the first orthodontic treatment. The special anatomical position of the complex supernumerary teeth made tooth extraction challenging. Given the higher risk status of surgery, we implemented a novel tooth extracting technique for this patient. Thus, in this study, we describe a case of minimally invasive extraction of bilateral mandibular impacted supernumerary teeth using a digital 3D positioning guide plate.

Comparing pre- and postoperative etoricoxib administration versus only postoperative on third molar extraction sequelae and oral health quality of life: a prospective quasi-experimental study.

OBJECTIVES: This study aimed to compare the impact of pre- and postoperative etoricoxib administration versus only postoperative on third molar extraction sequelae and oral health quality of life. MATERIALS AND METHODS: This prospective quasi experimental study involved 56 patients, divided into a study group receiving preemptive etoricoxib 120 mg before surgery and postoperative etoricoxib 120 mg (n = 28), and a control group receiving preemptive placebo before surgery and postoperative etoricoxib 120 mg (n = 28). Follow-up assessments were conducted at 3- and 7-days post-surgery, recording swelling, trismus, and adverse events. Patients rated perceived pain using the visual analog scale (VAS) and completed an oral health-related quality of life (OHRQoL) questionnaire at specified intervals. Statistical analysis employed non-parametric tests (i.e., the Mann-Whitney test, Friedman test, and Wilcoxon sign test) with P < 0.05. RESULTS: Significantly lower VAS scores were reported in the study group throughout the follow-up period (P < 0.05). Pharmacological protocol did not have a significant impact on postoperative edema and trismus (P > 0.05). However, double etoricoxib intake significantly improved postoperative quality of life on day 3 after surgery (P < 0.05). CONCLUSIONS: Pre- and postoperative etoricoxib 120 mg intake in third molar surgery reduced postoperative pain and enhanced postoperative quality of life on day 3 after surgery. Importantly, it was equally effective in managing swelling and trismus compared to exclusive postoperative intake. CLINICAL RELEVANCE: Preemptive etoricoxib use may decrease patient discomfort following impacted mandibular third molar extraction.

Can concentrated growth factor prevent postoperative complications of impacted third molar surgery? A split-mouth randomized double-blind trial.

OBJECTIVES: The purpose of the present study was to evaluate the effect of concentrated growth factor (CGF) on prevention of postoperative complications in the impacted third molar extraction. MATERIALS AND METHODS: A total of 25 healthy patients with symmetrical bilaterally impacted third molars (50 extraction sites) were enrolled in this split-mouth, randomized, double-blind clinical trial. Third molar extractions were performed in both sites of the mandible at the same appointment. Randomization was performed using a coin toss to choose the test and control sites. CGF was placed in the extraction socket and the socket was sutured (test group), while the contralateral socket was only sutured (control group). Each patient acted as their own control. The primary outcome were pain assessed by visual analog scale (VAS) and facial swelling on the1st, 3rd and 7th postoperative days. The secondary outcomes were bone healing in extraction sockets through alveolar bone height (ABH) and alveolar bone density (ABD) evaluated by cone beam computed tomography (CBCT) immediately after extraction and in the 3rd and 6th months. RESULTS: Twenty-five patients (12 female, 13 male; mean age 29.17) with bilateral impacted third molars participated in the study. A statistically significant reduction in pain was determined on the 3rd and 7th postoperative days in the CGF sites compared to the control sites while no statistically significant difference was found between the groups on the 1st postoperative day (3rd day, p = 0.009; 7th day, p = 0.039). There were no statistically significant differences in facial swelling and bone healing between the test and control groups at different time intervals, although the data obtained were slightly favoring the CGF group (p > 0.05). There were no serious adverse effects such as infection, alveolitis, paraesthesia, fracture through the follow-up period in all of the cases. CONCLUSION: The study has demonstrated the effect of CGF on relieving the severity of pain after the third molar extraction. CLINICAL RELEVANCE: Placement of CGF in the extraction socket could relieve postoperative pain and reduce patient discomfort after the third molar extraction. CGF is recommended during the third molar extraction due to its good biological effects, low cost and simple preparation procedures. TRIAL REGISTRATION NUMBER: ChiCTR2300077819.

Investigation of the relationship between the mandibular third molar teeth and the inferior alveolar nerve using posteroanterior radiographs: a pilot study.

BACKGROUND: The most severe complication that can occur after mandibular third molar (MM3) surgery is inferior alveolar nerve (IAN) damage. It is crucial to have a comprehensive radiographic evaluation to reduce the possibility of nerve damage. The objective of this study is to assess the diagnostic accuracy of panoramic radiographs (PR) and posteroanterior (PA) radiographs in identifying the association between impacted MM3 roots and IAN. METHODS: This study included individuals who had PR, PA radiographs, and cone beam computed tomography (CBCT) and who had at least one impacted MM3. A total of 141 impacted MM3s were evaluated on CBCT images, and the findings were considered gold standard. The relationship between impacted MM3 roots and IAN was also evaluated on PR and PA radiographies. The data was analyzed using the McNemar and Chi-squared tests. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of PR and PA radiographies were determined. RESULTS: Considering CBCT the gold standard, the relationship between MM3 roots and IAN was found to be statistically significant between PR and CBCT (p = 0.00). However, there was no statistically significant relationship between PA radiography and CBCT (0.227). The study revealed that the most prevalent limitation of the PR in assessing the relationship between MM3 roots and IAN was the identification of false-positive relationship. CONCLUSIONS: PA radiography may be a good alternative in developing countries to find out if there is a contact between MM3 roots and IAN because it is easier to get to, cheaper, and uses less radiation.

Immediate loading of implants inserted through impacted teeth in the aesthetic area: A retrospective study with a mean follow-up period of 7 years.

PURPOSE: To evaluate the survival and success rate of and the incidence of complications affecting implants inserted and immediately loaded in sites where an impacted tooth was present in the maxilla. MATERIALS AND METHODS: A total of 10 patients were treated and 14 implants were inserted, 4 in healed sites and 10 in extraction sites. The implant site preparation started in the crestal bone and continued in the enamel and dentine of the impacted tooth. The radiographic depth of implant penetration into the impacted tooth, peri-implant soft tissue and hard tissue condition at the 1-year follow-up and the last follow-up appointment, marginal bone loss at the 1-year follow-up and the last follow-up appointment, and the final aesthetic result were evaluated. RESULTS: The implants healed uneventfully with an adequate hard and soft tissue response and no adverse clinical or radiographic signs or symptoms. They were in function for a minimum of 3 and a maximum of 11 years (mean 7.2 years). CONCLUSION: Although further studies with a larger sample size are required to validate this unconventional approach, it can be considered a valuable clinical option to replace teeth in an area of impaction.

The use of panoramic radiographs to address the oral health needs of vulnerable Canadian populations.

Background: The high demand for oral health care services among vulnerable individuals combined with limited available resources requires a rethinking of the provision of oral health services. This study aimed to determine the usefulness of the dental panoramic radiograph (DPR) as an imaging tool to assess oral health and prioritize dental interventions in vulnerable patients. Methods: This observational and retrospective study evaluated charts of patients who attended Public Health Dental Clinics (PHDC), Alberta Health Services (AHS), in Calgary, Canada, between January 2018 and December 2019. Data collected included sex and age at the time of image acquisition. The following radiographic findings were gathered: the number of missing, present, decayed, restored, and impacted teeth; periapical lesions; retained root; periodontal bone loss; odontogenic and non-odontogenic lesions in the jaws; carotid calcification; and incidental radiographic findings with clinical relevance. Results: Of the 526 DPRs evaluated, 57.4% were from male patients and 42.6% were from female patients, with a mean age of 38.5 years. The average number of present teeth in females and males was 23.7 and 22.6, respectively. The most prevalent dental-related finding was periodontal bone loss (81.5%), followed by periapical lesions (59.6%) and impacted teeth (27%). Among non-dental findings, osseous lesions of the jaws were found in 10.4% of the patients, and carotid atheroma had a frequency of 3.2%. Conclusion: The DPR is a useful adjunct to the clinical exam in this specific population. It provides an opportunistic overview of their oral health and necessary support to establish priorities in oral health care in a public health setting.

Contexte : La forte demande de services de santé buccodentaire chez les personnes vulnérables, combinée aux ressources limitées disponibles, nécessite de repenser la prestation des services de santé buccodentaire. Cette étude vise à déterminer l'utilité de la radiographie panoramique comme outil d'imagerie pour évaluer la santé buccodentaire et prioriser les interventions dentaires chez les patients vulnérables. Méthodes : Cette étude observationnelle et rétrospective a évalué les dossiers des patients qui ont fréquenté les cliniques dentaires de santé publique d'Alberta Health Services (AHS) à Calgary, au Canada, entre janvier 2018 et décembre 2019. Les données recueillies comprenaient le sexe et l'âge au moment de l'acquisition de l'image. Les résultats radiographiques suivants ont été recueillis : nombre de dents manquantes, présentes, cariées, réparées et incluses; lésions périapicales; racine résiduelle; perte osseuse parodontale; lésions odontogéniques et non odontogéniques dans les mâchoires; calcification carotidienne; et résultats radiographiques accessoires pertinents sur le plan clinique. Résultats : Parmi les 526 radiographies panoramiques évaluées, 57,4 % provenaient d'hommes et 42,6 % de femmes, avec un âge moyen de 38,5 ans. Le nombre moyen de dents présentes chez les femmes et les hommes était de 23,7 et 22,6, respectivement. La découverte la plus courante liée aux soins dentaires était la perte osseuse parodontale (81,5 %), suivie des lésions périapicales (59,6 %) et des dents incluses (27 %). En ce qui concerne les résultats non liés aux soins dentaires, des lésions osseuses des mâchoires ont été repérées chez 10,4 % des patients, et l'athérome carotidien avait une fréquence de 3,2 %. Conclusion : La radiographie panoramique est un complément utile à l'examen clinique dans cette population particulière. Elle donne un aperçu de leur santé buccodentaire et le soutien nécessaire pour établir les priorités en matière de soins buccodentaires dans un contexte de santé publique.

Relationship between Impacted Mandibular Third Molars and the Mandibular Canal on CBCT Scans.

This study aimed to assess the relationship of impacted mandibular third molars with the mandibular canal on cone beam computed tomography (CBCT) scans. This cross-sectional study was conducted on CBCT scans of 137 patients with 204 impacted mandibular third molars. The relation of age, gender, class of impaction, anatomical position of canal relative to tooth (buccal, lingual, inferior, inter-radicular), tooth angulation (mesioangular, vertical, distoangular, horizontal), relationship of tooth with the mandibular canal (no contact, in contact, relation), relationship of tooth with the mandibular cortex, anatomical site of contact of tooth with the mandibular cortex (buccal, lingual, inferior), and the impression of canal (grooving, no effect) on impacted teeth were evaluated. Data were analyzed using one-way ANOVA, Chi-square test and Fisher's exact test. Class B of impaction (78.9%), inferior position of canal relative to the impacted tooth (53.9%) and mesioangular angulation (53.4%) had the highest frequency, respectively. The relationship of tooth with the mandibular canal was "relation" in most cases (53.4%) followed by no contact (26.9%) and in contact (19.6%). Significant associations were noted between depth of impaction (P < 0.001), tooth angulation (P = 0.024), anatomical position of canal relative to tooth (P < 0.001), relationship of tooth with the mandibular cortex (P = 0.032) and anatomical site of contact of tooth with the mandibular cortex (P = 0.013) with the impacted tooth-mandibular canal relationship. CBCT provides accurate information about the relationship of impacted third molars with the mandibular canal and can decrease the risk of traumatization of inferior alveolar nerve (IAN) during their surgical extraction.