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.

Two-stage extraction by partial grinding of impacted mandibular third molar in close proximity to the inferior alveolar nerve.

BACKGROUND: Extraction of impacted third molars often leads to severe complications caused by damage to the inferior alveolar nerve (IAN). AIM: To proposes a method for the partial grinding of an impacted mandibular third molar (IMM3) near the IAN to prevent IAN injury during IMM3 extraction. METHODS: Between January 1996 and March 2022, 25 patients with IMM3 roots near the IAN were enrolled. The first stage of the operation consisted of grinding a major part of the IMM3 crown with a high-speed turbine dental drill to achieve sufficient space between the mandibular second molar and IMM3. After 6 months, when the root tips were observed to be away from the IAN on X-ray examination, the remaining part of the IMM3 was completely removed. RESULTS: All IMM3s were extracted easily without symptoms of IAN injury after extraction. CONCLUSION: Partial IMM3 grinding may be a good alternative treatment option to avoid IAN injury in high-risk cases.

Clinical Assessment of Preemptive Analgesia on Success of Pulpal Anesthesia and Postendodontic Pain in Children with Irreversible Pulpitis: A Randomized Comparative Study.

Introduction: Optimal pain management of symptomatic pulpitis in formative years goes a long way in developing a positive dental attitude. Efforts should be made to increase the success of anesthesia, thus diminishing negative dental experiences. The aim of the study was to assess the efficacy of preemptive analgesia on the success of pulpal anesthesia following inferior alveolar nerve block (IANB) in children with symptomatic irreversible pulpitis and on reducing postendodontic pain. Materials and methods: The research design was an in vivo, three-group, parallel, quadruple-blind study. A total of 75 patients were randomly allocated to one of the three groups-group I: ibuprofen, group II: combination of ibuprofen and paracetamol, and group III: multivitamin (placebo). Premedication was given 45 minutes before treatment, and patients received IANB in a standardized manner. Pain during pulpectomy was recorded using the face, legs, activity, cry, consolability (FLACC) scale and postoperatively using Wong-Baker's pain rating scale (WBPRS) at 4, 12, and 24 hours. Success was measured if the pain felt was of no or mild intensity. Results: Success of IANB was 64% for ibuprofen, 72% for the combination group, and 40% for the placebo group, with no statistically significant difference between all groups (p = 0.06) on the FLACC scale. At 4 hours postoperatively, a significant difference (p = 0.02) was found among groups with more children experiencing no or mild pain in groups I and II and the highest number of rescue medications taken by the placebo group. Conclusion: Ibuprofen and a combination of ibuprofen and acetaminophen as preemptive analgesics had no significant effect on the success rate of IANB, although it was effective in reducing pain at 4 hours postoperatively. How to cite this article: Gori NA, Patel MC, Bhatt RK, et al. Clinical Assessment of Preemptive Analgesia on Success of Pulpal Anesthesia and Postendodontic Pain in Children with Irreversible Pulpitis: A Randomized Comparative Study. Int J Clin Pediatr Dent 2024;17(1):72-78.

The alveolar canals and foramina in the first edition of Terminologia Oroanatomica: a preview.

Anatomy was initially developed out of necessity to decrease surgery complications. Over time, anatomists and surgeons have sometimes used different terms for the same anatomical structures, thus resulting in numerous discrepancies in terminology between anatomy and surgery. To avoid any confusion or misunderstanding and to better elucidate the oral anatomy terms, the Federative International Programme for Anatomical Terminology (FIPAT) organized a group of specialists on oral anatomy, Terminologia Oroanatomica (ToA) working group, composed of dentists, anatomy researchers, anatomy educators, oral and maxillofacial surgeons, and oral and maxillofacial radiologists. Within the ToA working group, major anatomical structures in the mandible, such as the mandibular canal, were focused and discussed to determine the most appropriate term, i.e., inferior alveolar canal. Although yet to be approved by the International Federation of Associations of Anatomists (IFAA), this article will preview some changes suggested by the ToA.

Is 3T MR nerve-bone fusion imaging a viable alternative to MRI-CBCT to identify the relationship between the inferior alveolar nerve and mandibular third molar.

OBJECTIVES: To investigate the feasibility of MRI nerve-bone fusion imaging in assessing the relationship between inferior alveolar nerve (IAN) / mandibular canal (MC) and mandibular third molar (MTM) compared with MRI-CBCT fusion. MATERIALS AND METHODS: The MRI nerve-bone fusion and MRI-CBCT fusion imaging were performed in 20 subjects with 37 MTMs. The Hausdorff distance (HD) value and dice similarity coefficient (DSC) was calculated. The relationship between IAN/MC and MTM roots, inflammatory, and fusion patterns were compared between these two fused images. The reliability was assessed using a weighted κ statistic. RESULTS: The mean HD and DSC ranged from 0.62 ~ 1.35 and 0.83 ~ 0.88 for MRI nerve-bone fusion, 0.98 ~ 1.50 and 0.76 ~ 0.83 for MRI-CBCT fusion. MR nerve-bone fusion had considerable reproducibility compared to MRI-CBCT fusion in relation classification (MR nerve-bone fusion κ = 0.694, MRI-CBCT fusion κ = 0.644), direct contact (MR nerve-bone fusion κ = 0.729, MRI-CBCT fusion κ = 0.720), and moderate to good agreement for inflammation detection (MR nerve-bone fusion κ = 0.603, MRI-CBCT fusion κ = 0.532, average). The MR nerve-bone fusion imaging showed a lower ratio of larger pattern compared to MR-CBCT fusion (16.2% VS 27.3% in the molar region, and 2.7% VS 5.4% in the retromolar region). And the average time spent on MR nerve-bone fusion and MRI-CBCT fusion was 1 min and 3 min, respectively. CONCLUSIONS: Both MR nerve-bone fusion and MRI-CBCT fusion exhibited good consistency in evaluating the spatial relationship between IAN/MC and MTM, fusion effect, and inflammation detection. CLINICAL RELEVANCE: MR nerve-bone fusion imaging can be a preoperative one-stop radiation-free examination for patients at high risk for MTM surgery.

Use of Adult Dry Human Mandibles to Study of Mandibular Foramen from Various Bony Landmarks.

Background: Precise knowledge of the mandibular foramen's location is essential for clinical and surgical procedures, especially the inferior alveolar nerve block. Variability in its position concerning different bony landmarks can significantly impact clinical outcomes. Materials and Methods: This study examined 30 Adult dry human mandibles to determine the mandibular foramen's positions in relation to specific bony landmarks: the occlusal plane, posterior border of the ramus, and lingula. Measurements were obtained using a calibrated digital caliper, and statistical analysis was performed. Results: The study revealed significant variations in the position of the mandibular foramen. In relation to the occlusal plane, the mandibular foramen was found at an average height of approximately 15.2 mm (±2.1 mm). Regarding the posterior border of the ramus, it was situated at an average distance of about 18.5 mm (±3.4 mm). In relation to the lingula, the average distance was approximately 21.8 mm (±4.0 mm). These results underscore the considerable individual differences and anatomical variations in the mandibular foramen's location among the studied specimens. Conclusion: The observed variations in the position of the mandibular foramen emphasize the need for clinicians and surgeons to be cognizant of these differences when performing procedures involving the inferior alveolar nerve block. Understanding these anatomical variations is crucial for enhancing clinical precision, reducing complications, and ensuring optimal outcomes.

Flipped classroom teaching model with video instruction improves skills in local anesthesia training.

Background/purpose: Local anesthesia (LA) training is an essential clinical skill in dental education. However, the traditional teaching method of student-to-student injection has ethical concerns. This study investigated whether a flipped classroom (FC) teaching model with instructional videos improves students' skills in administering LA. Materials and methods: Fourth-year dental students in 2017 (traditional teaching, n = 70) and 2018 (FC model, n = 79) were assessed for their ability to perform an inferior alveolar nerve block and lingual nerve block. The FC group watched pre-recorded videos prior to a hands-on training session. Skills were evaluated using a 24-item checklist converted to letter grades. Perceptions of the FC approach were also surveyed. Results: The FC group showed statistically significantly higher final grades than the traditional teaching group (P < 0.05). Most FC students agreed that the videos improved clarity and learning objectives. Conclusion: The FC teaching model with procedural video instruction improved skills and confidence in administering LA over traditional teaching methods. Videos can be a beneficial supplement in pre-clinical dental training.

The Management of a Geriatric Patient Using Dabigatran Therapy on Dentigerous Cyst with Oral Bleeding.

Jaw cysts represent a great matter of interest in oral and maxillofacial surgery. Jaw cyst surgery is a common intervention in oral surgery but, in the case of a multidisciplinary patient, the oral surgeon needs to meet with other specialists. A cyst is an epithelium-lined sac containing fluid and/or semisolid material due to epithelial cell proliferation, degeneration, and liquefaction; the hypertonic solution withdraws liquids from the surrounding tissues, while internal pressure exerts an equal strength on the cyst walls. Dentigerous cysts are the second most common odontogenic cysts after radicular cysts, and commonly few or no symptoms are reported. However, the most common diagnosis for dentigerous cyst is represented by eruption of the affected tooth or accidental diagnosis. Commonly, dentigerous cysts may be related to impacted third molars; in the case of impacted third molars and a dentigerous cyst, the tooth should be removed along with the cyst in the same intervention. Mandibular dentigerous cysts are common in children and adults, while dentigerous cysts are a rare neoformation in elderly patients. Treatment usually involves removal of the entire cyst and the associated unerupted tooth. This intervention may be more difficult if the cyst is large, the third molar is in contact with the mandibular nerve, and/or the patient has a medical history that may represent a relative or absolute contraindication. We present the case of a rare symptomatic manifestation of dentigerous cyst in an elderly patient in treatment with dabigatran therapy; for the treatment of dentigerous cysts in the elderly, we suggest a multidisciplinary approach with the use of the histological examination and a careful follow-up.

Efficacy of Different Techniques of the Inferior Alveolar Nerve Block for Mandibular Anesthesia: A Comparative Prospective Study.

Background The inferior alveolar nerve block (IANB) is a commonly employed technique in oral surgery for achieving profound anesthesia in the mandibular teeth and associated structures. Several techniques have been developed to enhance the success rate and patient comfort during the IANB. The aim of this study was to compare and evaluate the efficacy of different IANB techniques for mandibular anesthesia.  Materials and methods The participants included in the study were adults requiring surgical extraction of an impacted mandibular third molar teeth. A total of 100 participants were randomly assigned to five different groups representing various techniques of IANB, i.e., conventional Halsted technique, Vazirani-Akinosi technique, Gow-Gates technique, Fischer 1-2-3, and extraoral Kurt-Thoma technique, with 20 participants in each group. The participants were evaluated for the onset of anesthesia using subjective and objective methods, pain perception during the administration of local anesthesia using a 10-point visual analogue scale (VAS), and the incidence of trismus postoperatively. Data were analyzed using IBM SPSS Statistics for windows, version 23.0 (released 2015; IBM Corp Armonk, United States) with p-values less than 0.05 considered as statistically significant. Descriptive statistics, Kruskal-Wallis, and post-hoc tests were included in the data analysis for intergroup comparisons. Results The primary outcomes evaluated were the onset of anesthesia, the patient's perception of pain during the administration of local anesthesia, and the secondary outcome included in the incidence of trismus. In this study, it was found that the Kurt-Thoma technique had the fastest onset of anesthesia (2.25 minutes), higher incidence of trismus (25%), and higher pain perception (6.5 score on VAS). The conventional Halstead technique (3.55 minutes), Fischer 1-2-3 technique (3.5 minutes), and Vazirani-Akinosi technique (3.1 minutes) had an almost similar mean duration of anesthesia. The onset of anesthesia was delayed in the Gow-Gates technique (5.1 minutes). Patient perception of pain during administration of local anesthesia was higher in the Kurt-Thoma (6.5) and Gow-Gates techniques (4.95), and it was least in the Fischer 1-2-3 technique (0.75) in the VAS scores. The incidence of trismus was highest with the Kurt-Thoma technique (25%), then the Gow-Gates technique (20%), followed by the conventional Halstead technique (5%).  Conclusion In this study, it was found that the conventional Halsted technique was the best among the different techniques of IANB and remains the gold standard.

Towards clinically applicable automated mandibular canal segmentation on CBCT.

OBJECTIVES: To develop a deep learning-based system for precise, robust, and fully automated segmentation of the mandibular canal on cone beam computed tomography (CBCT) images. METHODS: The system was developed on 536 CBCT scans (training set: 376, validation set: 80, testing set: 80) from one center and validated on an external dataset of 89 CBCT scans from 3 centers. Each scan was annotated using a multi-stage annotation method and refined by oral and maxillofacial radiologists. We proposed a three-step strategy for the mandibular canal segmentation: extraction of the region of interest based on 2D U-Net, global segmentation of the mandibular canal, and segmentation refinement based on 3D U-Net. RESULTS: The system consistently achieved accurate mandibular canal segmentation in the internal set (Dice similarity coefficient [DSC], 0.952; intersection over union [IoU], 0.912; average symmetric surface distance [ASSD], 0.046 mm; 95% Hausdorff distance [HD95], 0.325 mm) and the external set (DSC, 0.960; IoU, 0.924; ASSD, 0.040 mm; HD95, 0.288 mm). CONCLUSIONS: These results demonstrated the potential clinical application of this AI system in facilitating clinical workflows related to mandibular canal localization. CLINICAL SIGNIFICANCE: Accurate delineation of the mandibular canal on CBCT images is critical for implant placement, mandibular third molar extraction, and orthognathic surgery. This AI system enables accurate segmentation across different models, which could contribute to more efficient and precise dental automation systems.

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.

Systemic Corticosteroid Uses in Endodontics-Part 2: Enhancing the Success of Local Anesthesia.

INTRODUCTION: Chronic inflammation in irreversible pulpitis leads to heightened sensitivity of nociceptive receptors, resulting in persistent hyperalgesia. This poses significant challenges in achieving effective anesthesia for patients with irreversible pulpitis. Various anesthetic techniques and pharmacological approaches have been employed to enhance the success of local anesthesia. Recently, the preemptive use of anti-inflammatory agents, specifically corticosteroids, has gained attention and shown promising results in randomized controlled trials. This systemic review and meta-analysis aimed to evaluate the impact of systemically administered corticosteroids on enhancing anesthetic success in patients undergoing endodontic treatment. METHODS: A comprehensive search was conducted across multiple databases including PubMed, Cochrane Library, Embase, Scopus, Dentistry & Oral Science, and ProQuest. Additionally, the references of primary studies and related systematic reviews were manually searched for additional relevant publications. The primary outcome assessed was the success of anesthesia, and the effect measure was risk ratio using the random-effects inverse variance method. Statistical significance was set at P < .05. The certainty of the evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: Twelve studies involving 917 participants were analyzed to determine the frequency of successful anesthesia. The corticosteroid group demonstrated a significantly higher number of patients achieving successful anesthesia (risk ratio = 1.66; 95% confidence interval, 1.34-2.06;P < .00001). However, heterogeneity within the pooled data analysis was observed (I2 = 57%, P = .007). CONCLUSIONS: Moderate certainty evidence indicates that preemptive use of systemic corticosteroids enhances the success of local anesthesia, specifically inferior alveolar nerve block, in cases of irreversible pulpitis.

Coronectomy of impacted mandibular third molars: a clinical and radiological retrospective case series study with 2-9 years of follow-up / Coronectomía de terceros molares mandibulares impactados: un estudio de serie de casos retrospectivo clínico y radiológico con 2-9 años de seguimiento

Background: Impacted mandibular third molars occasionally are in intimate relation to the inferior alveolar nerve (IAN). Coronectomy has been proposed as a good alternative to prevent injury of the IAN. The present study evaluates the clinical and radiological outcomes of impacted mandibular third molars presenting radiographic signs associated with a high risk of IAN injury, and which were treated with the coronectomy technique. Material and Methods: A retrospective case series evaluated the outcomes of coronectomies of impacted mandibular third molars. The inclusion criteria were: available preoperative, immediate postoperative and two-year panoramic radiographs, preoperative cone-beam computed tomography (CBCT), and a complete case history. The clinical evaluation comprised intraoperative complications (mobilized fragments of root and damage to adjacent structures), short-term complications (sensory alterations and postoperative infection), and long-term complications (infection or oral exposure). The IAN position with respect to the roots, root shape, eruption status, third molar position, radicular-complex migration and bone above roots were radiographically evaluated as well. Results: Approximately a total of 2000 mandibular third molars were removed from 2011 to 2022. Of these, 39 molars in 34 patients were partially extracted using the coronectomy technique. The mean age was 36 years (range 22-77), and the mean follow-up was 28 months (range 24-84). There were two short-term postoperative infections. One of them was resolved through reintervention to remove the roots after antibiotic treatment, while the other required hospital admission and removal of the roots. One case of short-term transient lingual paresthesia was also recorded. Two long-term oral exposures were detected, and the root fragments had to be extracted. There were no permanent sensory alterations...(AU)

Anatomical Analysis of Inferior Alveolar Nerve Relation to Mandibular Posterior Teeth Using Cone Beam Computed Tomography: A Retrospective Radiographic Analysis Study.

Introduction: Cone beam computed tomography (CBCT) is reliable in the assessment of structures related to teeth. The assessment of the inferior alveolar neurovascular (IAN) bundle location using CBCT is considered one of its prime uses in different mandibular surgeries. Methodology: Retrospective CBCT data of patients presented to the institute were assessed to measure relations of IAN. Measurements were taken to assess the bone thickness adjacent to IAN, the superior-inferior dimension between the canal and the teeth, and the dimension between the canal and the inferior border of the mandible. Results: Out of the 170 patients the root apices nearest to the IAN were that of the second molars (1.76 ± 1.86 mm). The IAN was closest to the inferior border of the mandible at the roots of the second molars (8 ± 3.4 mm). The buccal bone thickness had its greater dimension buccal to the IAN at the area of the second molar (5.16 ± 1.26 mm). Conclusion: Two mini-plates in trauma do not increase the risk of injury. It is advisable in apicectomy not to extend 1.5 mm apically. The thickness of the nerve-lateralization window should not exceed 2 mm. In body osteotomy procedure, perform surgery anterior to premolars as much as possible.

Comparison of Neurosensory Recovery of the Inferior Alveolar Nerve After Open and Closed Reduction for Mandibular Fractures: A Prospective Study.

INTRODUCTION: Traumatic mandibular fractures are the most common fractures of the facial region and are associated with loss of neurosensation in the inferior alveolar nerve (IAN). The present study aimed to compare IAN recovery after traumatic mandibular fractures between the open and closed reduction methods. MATERIALS AND METHODS: The study included 90 patients with traumatic mandibular fractures of the body, angle, and symphysis, divided into two groups of 45 patients: group 1 was treated with closed reduction and fixation with rich arch-bar fixation under local anesthesia, and group 2 was treated with open reduction and rigid internal fixation with 2-mm titanium mini plates and monocortical screws (6 mm), and the plate was fixed to the fractured bony fragments. All patients underwent neurosensory testing using the Zuniga and Essick algorithm at baseline (preoperative), one week after surgery (postoperative), at three months, and at six months of follow-up. RESULTS: No statistically significant differences were observed in IAN recovery between the groups. The most common site of fracture was the body (44% in group 1 and 56% in group 2). The maximum recovery was observed in the younger age group (25-30 years). At baseline, functional nerve recovery was observed in 40 cases (88%) in group 1 and 38 cases (84%) in group 2, and the difference was not statistically significant. Levels A and B tests were affected by surgical management and improved after three months. The total recovery in group 1 ranged from 60% to 80%, and that in group 2 ranged from 56% to 72%. CONCLUSION: Based on the findings of the current study, both methods are recommended for surgical management of traumatic mandibular fractures with IAN recovery in 60-80% of cases six months postoperatively.

Effect of preemptive use of a nonsteroidal anti-inflammatory drug and a corticosteroid on the efficacy of inferior alveolar nerve blockade and postoperative pain control in endodontic treatment of molars with symptomatic pulpitis: A randomized double-blind placebo-controlled clinical trial.

AIM: The anaesthetic success rate of an inferior alveolar nerve block (IANB) in mandibular molars with irreversible symptomatic pulpitis can be low, and postoperative pain control in teeth with this diagnosis can be challenging. This study aimed to evaluate the influence of preemptive use of dexamethasone and oral potassium diclofenac on the success of IANB. The influence of these drugs on the intensity of postoperative pain was assessed as a secondary outcome. METHODOLOGY: Eighty-four patients with mandibular molars diagnosed with irreversible symptomatic pulpitis recorded preoperative pain intensity using a cold thermal test and a modified Numerical Rating Scale (mNRS). Sixty minutes before the anaesthetic procedure, patients were randomly assigned to one of three groups based on the medication they received: dexamethasone (4 mg), diclofenac potassium (50 mg), or placebo. All patients received IANB with 4% articaine (1:200 000 epinephrine), and 15 min later, they were evaluated for pain intensity using the cold thermal test. Anaesthetic success was analysed. The pain intensity was then recorded, and endodontic treatment and provisional restoration of the tooth were executed in a single session. Patients were monitored for 6, 12, 24, 48 and 72 h using the mNRS to assess the intensity of postoperative pain. RESULTS: There was a statistically significant increase in anaesthetic success when 4 mg dexamethasone (39.3%) or 50 mg diclofenac potassium (21.4%) was used compared to the placebo group (3.6%) (p < .001), with no significant difference between the two drugs. Regarding postoperative pain, dexamethasone was superior to placebo at 6 h (p < .001), with diclofenac having an intermediate behaviour, not differing between dexamethasone and placebo (p > .05). There was no significant difference amongst the groups at 12 h (p > .05). At 24, 48 and 72 h, the effectiveness of dexamethasone and diclofenac were comparable, and both were superior to placebo (p < .001). CONCLUSION: The use of dexamethasone or diclofenac potassium was favourable in terms of increasing the success rate of inferior alveolar nerve block in cases of mandibular molars with irreversible symptomatic pulpitis and decreased the occurrence of postoperative pain when compared to the use of a placebo.

Effect of betamethasone injection into the pterygomandibular space on the neurosensory disturbance after bilateral sagittal split ramus osteotomy: a pilot study.

AIM: The aim of this study was to evaluate the effect of local betamethasone injection into the pterygomandibular space on postoperative neurosensory deficits. MATERIALS AND METHODS: A prospective controlled clinical study was conducted on 16 patients (6 male, 10 female; mean age, 24.95 ± 9.22 years) who underwent bilateral sagittal ramus osteotomy for mandibular discrepancies. One side of each patient's mandible was randomly selected as the control side, and the opposite side as the experimental side. On the experimental side, a solution of betamethasone (6 mg/1 ml) was injected into the pterygomandibular space after the completion of wound closure. Neurosensory tests, including light touch, two-point discrimination, direction of movement, thermal sensitivity, and pin-prick discrimination, were performed. The follow-up period ranged between 6 and 12 months, according to the particular sensory test. The Fisher exact test was used to analyse the data. RESULTS: The light touch sensation was abnormal in 75% of the control side and 31% of the study side, with the difference being significant (p = 0.03). However, at 6 months, all the study cases regained touch sensation, compared to 69% of the control side. No significant difference in direction movement discrimination was seen; however, at 3 months, the study side showed significantly less direction sensation (19%) compared to the control side (56%) (p = 0.02). There was no significant difference in the two-point discrimination; however, at 3 months, the study side had a significantly less abnormal two-point sensation (13%) than the control side (56%) (p = 0.02). In addition, no significant difference was noted in thermal sensitivity or pin-prick sensation. CONCLUSION: Betamethasone injection into the pterygomandibular space reduces neurosensory disturbances after bilateral sagittal split ramus osteotomies nd leads to faster recovery of sensations.

System for automatically assessing the likelihood of inferior alveolar nerve injury.

Inferior alveolar nerve (IAN) injury is a severe complication associated with mandibular third molar (MM3) extraction. Consequently, the likelihood of IAN injury must be assessed before performing such an extraction. However, existing deep learning methods for classifying the likelihood of IAN injury that rely on mask images often suffer from limited accuracy and lack of interpretability. In this paper, we propose an automated system based on panoramic radiographs, featuring a novel segmentation model SS-TransUnet and classification algorithm CD-IAN injury class. Our objective was to enhance the precision of segmentation of MM3 and mandibular canal (MC) and classification accuracy of the likelihood of IAN injury, ultimately reducing the occurrence of IAN injuries and providing a certain degree of interpretable foundation for diagnosis. The proposed segmentation model demonstrated a 0.9 % and 2.6 % enhancement in dice coefficient for MM3 and MC, accompanied by a reduction in 95 % Hausdorff distance, reaching 1.619 and 1.886, respectively. Additionally, our classification algorithm achieved an accuracy of 0.846, surpassing deep learning-based models by 3.8 %, confirming the effectiveness of our system.

Is it possible to predict neurosensory alterations in impacted lower third molar removal based on preoperative imaging procedures? A prospective cohort study / ¿Es posible predecir alteraciones neurosensoriales en la extracción del tercer molar inferior impactado basándose en procedimientos de imagen preoperatorios? Un estudio de cohorte prospectivo

Background: Surgical extraction of the lower third molar (LTM) may trigger neurosensory injury of the inferioralveolar nerve, making extraction a real challenge. This study set out to assess whether is it possible to predictneurosensory alterations from preoperative imaging.Material and Methods: A total of 99 patients underwent 124 impacted lower third molar (ILTM) surgeries. Priorto surgery, panoramic and CBCT images were evaluated in an attempt to predict a neurosensory disturbance.Preoperative data (ILTM position, panoramic radiograph signs, inferior alveolar nerve (IAN) location and its con-tact with the ILTM roots) and intra/postoperative findings (extraction difficulty and sensitivity alterations) wererecorded. Descriptive and bivariate data analysis was performed. Statistical comparison applied the chi-squaretest, Fisher test, and one-way ANOVA test. Statistical significance was established with a confidence interval (CI)of 95%.Results: In 4.03% of cases, patients experienced neurosensory alterations. Of 124 ILTM positions in panoramicradiographs, 76 cases were considered to exhibit a potential neurosensory risk as they presented two or more typesof superimposed relationships between ILTM and mandibular canal. Of these, alterations were reported in onlythree cases (3.95%). Of the 48 remaining ILTM images presenting only one sign, neurosensory alterations wereobserved in two cases (4.17%). No permanent alterations were recorded in any of the five cases observed.Conclusions: Within the limitations of the present study, prediction of neurosensory alterations prior to ILTMextraction by means of preoperative imaging did not show a significant statistical correlation with post-surgicalincidence. Nevertheless, interruption of the canal´s white line (ICWL) or a diversion of the canal (DC) may predictan increased risk of IAN injury.(AU)