With the growing demand for dental work, trigeminal nerve injuries are increasingly common. This retrospective cohort study examined 53 cases of iatrogenic trigeminal nerve injury seen at the Department of Oral and Maxillofacial Surgery, University Hospitals of Leuven between 2013 and 2014 (0.6% among 8845 new patient visits). Patient records were screened for post-traumatic trigeminal nerve neuropathy caused by nerve injury incurred during implant surgery, endodontic treatment, local anaesthesia, tooth extraction, or specifically third molar removal. The patients ranged in age from 15 to 80years (mean age 42.1years) and 68% were female. The referral delay ranged from 1day to 6.5years (average 10months). The inferior alveolar nerve (IAN) was most frequently injured (28 cases), followed by the lingual nerve (LN) (21 cases). Most nerve injuries were caused during third molar removal (24 cases), followed by implant placement (nine cases) and local anaesthesia injuries (nine cases). Pain symptoms were experienced by 54% of patients suffering IAN injury, compared to 10% of patients with LN injury. Persistent neurosensory disturbances were identified in 60% of patients. While prevention remains the key issue, timely referral seems to be a critical factor for the successful treatment of post-traumatic neuropathy.

Objectives: Three-dimensional models of mandibular condyles provide a way for condylar remodeling follow-up. The overall aim was to develop and validate a user-friendly workflow for cone beam CT (CBCT)-based semi-automatic condylar registration and segmentation. Methods: A rigid voxel-based registration (VBR) technique for registration of two post-operative CBCT-scans was tested. Two modified mandibular rami, with or without gonial angle, were investigated as the volume of interest for registration. Inter- and intraoperator reproducibility of this technique was tested on 10 mandibular rami of orthognathic patients by means of intraclass correlation coefficients (ICC’s) and descriptive statistics of the transformation values from the VBR. The difference in reproducibility between the two modified rami was evaluated using a paired t-test (p < 0.05). For the segmentation, eight fresh frozen cadaver heads were scanned with CBCT and micro-CT. These data were used to test the inter- and intraoperator reproducibility (ICC’s) and accuracy (Bland–Altman plot) of a newly designed workflow based on semi-automated contour enhancement. Results: Excellent ICC’s (0.94–0.99) were obtained for the voxel-based registration technique using both modified rami. If the gonial angle was not included in the volume of interest, there was a trend of increased operator error suggested by significant higher interoperator differences in translation values (p = 0,0036). The segmentation workflow proved to be highly reproducible with excellent ICC’s (0.99), low absolute mean volume differences between operators (23.19 mm3), within operators (28.93 mm3) and low surface distances between models of different operators (<0.20 mm). Regarding the accuracy, CBCT-models slightly overestimate the condylar volume compared to micro-CT. Conclusions: This study provides a validated user-friendly and reproducible method of creating three-dimensional-surface models of mandibular condyles out of longitudinal CBCT-scans.

Background Post‐traumatic trigeminal neuropathy (PTN) is a disturbance of function or pathological change of the trigeminal nerve branches following trauma and has an important impact on patient's quality of life (QoL). Objectives To provide diagnostic data on PTN and illustrate differences in aetiology, injured nerve, pain distribution, sensory profile and QoL between PTN subgroups. Methods 1331 patients with painful or non‐painful PTN were retrospectively reviewed in two centres, extracting demographic data, time and cause of trauma, clinical findings including signs and symptoms, basic neurosensory testing, imaging modalities, treatments, and QoL or psychosocial assessment. Results More females were represented (70%) than males. The inferior alveolar nerve was most frequently damaged (60%) followed by the lingual nerve (28%). Wisdom teeth removal was considered the main cause (48%). Pain was reported in 63% of patients and pain frequency increased with age without clinically significant gender differences. Numbness was reported in 50% of PTN patients. Neurosensory testing showed larger affected dermatome involvement in persistent injuries, with no differences between the non‐painful and painful PTN groups. Patient clustering indicated different sensory profile distributions when stratified according to aetiology or affected nerve branch. High interference with lifestyle was reported (78%), and patients suffering from painful PTN had worse QoL and psychosocial outcomes. Conclusion Patients with painful PTN had different clinical profiles and lower QoL scores than those with non‐painful PTN. Sensory profiles may provide important prognostic and therapeutic information; however, more research is needed to assess the clustering procedure and link these clusters to therapeutic guidelines.

Oral Surgery 13 (2020) 389-403.

This study investigated the feasibility of a 3D black-blood STIR TSE sequence with a pseudo steady-state sweep and motion-sensitized driven equilibrium pulse for extraforaminal cranial nerve imaging on a 3T system. Assessments of healthy volunteers showed near-perfect agreement in nerve visualization with excellent to good visualization of the extraforaminal trigeminal, greater occipital, and facial nerves. Suppression of surrounding tissues was excellent to good. 3D cranial nerve imaging can produce nerve selective imaging of extraforaminal cranial and spinal nerve branches.