Signs and symptoms, quality of life and psychosocial data in 1331 post-traumatic trigeminal neuropathy patients seen in two tertiary referral centres in two countries

Permanent lingual nerve injury after dental procedures: a retrospective study of 228 patients

Lingual nerve injury (LNI) is a rare, serious complication and previous studies include limited numbers of cases. The aim of this retrospective study was to report the neurosensory outcomes for a large patient cohort with permanent LNI and correlate the mechanism of injury (surgical vs non-surgical) to neurosensory characteristics. Demographics, procedural parameters, mandibular third molar (M3) position, surgeon type, neurosensory test results, and symptoms were recorded for 228 patients and analysed. The majority were female (67.1%). Overall, 59.6% of LNIs were caused by M3 removal and 36.4% by local anaesthesia. Complete loss occurred more frequently in surgical LNIs (P = 0.013). The presence of pain did not differ significantly, however the burning type of pain was significantly more frequent in non-surgical LNIs (P = 0.008) along with altered gustation (P = 0.025). The most common M3 position related to LNI was distoangular (40.4%), class III (63.2%), level A (58.1%) (Winter/Pell and Gregory classifications). The majority of patients undergoing M3 removal were >24 years. A total of 71.7% showed no sign of recovery and 5.5% reported further impairment in their condition. Overall, nine patients underwent microsurgical repair. This study presents neurosensory characteristics potentially decisive for timely referral of operable LNIs.

Evaluating Stromal Vascular Fraction As a Treatment for Peripheral Nerve Regeneration: A Scoping Review

PURPOSE

This study aims to investigate the potential of stromal vascular fraction (SVF) for peripheral nerve regeneration.

METHODS

A scoping review of Scopus and PubMed databases was conducted. Inclusion criteria were human or animal studies exploring the use of SVF for peripheral nerve regeneration. Studies were categorized by assessed outcomes: pain assessment, neural integrity, muscle recovery, and functional recovery. Level of evidence and study quality were assessed.

RESULTS

Nine studies met the inclusion criteria. SVF injection in humans with trigeminal neuropathic pain reduced pain scores from 7.5 ± 1.58 to 4.3 ± 3.28. SVF injection improved sensation in humans with leprosy neuropathy. Repairing transected rat sciatic nerves with SVF-coated nerve autografts improved wet muscle weight ratios (0.65 ± 0.11 vs 0.55 ± 0.06) and sciatic functional index (SFI) scores (-68.2 ± 9.2 vs -72.5 ± 8.9). Repairing transected rat sciatic nerves with SVF-coated conduits increased the ratio of gastrocnemius muscle weights (RGMW) (7-10% improvement), myelinated fibers (1,605 ± 806.2 vs 543.6 ± 478.66), and myelin thickness (5-20% increase). Repairing transected rat facial nerves with SVF-coated conduits improved whisker motion (9.22° ± 0.65° vs 1.90° ± 0.84°) and myelin thickness (0.57 μm ± 0.17 vs 0.45 μm ± 0.14 μm). Repairing transected rat sciatic nerves with SVF-coated nerve allografts improved RGMW (85 vs 50%), SFI scores (-20 to -10 vs -40 to -30), and Basso, Beatie, and Bresnahan locomotor scores (18 vs 15). All metrics mentioned above were statistically significant. The human studies were level 4 evidence due to being case series, while animal studies were the lowest level of evidence.

CONCLUSION

Despite initial promising results, the low-level evidence from the included studies warrants further investigation.

Clinical insights into traumatic injury of the inferior alveolar and lingual nerves: a comprehensive approach from diagnosis to therapeutic interventions

OBJECTIVES

This scoping review explores the risk and management of traumatic injuries to the inferior alveolar and lingual nerves during mandibular dental procedures. Emphasizing the significance of diagnostic tools, the review amalgamates existing knowledge to offer a comprehensive overview.

MATERIALS AND METHODS

A literature search across PubMed, Embase, and Cochrane Library informed the analysis.

RESULTS

Traumatic injuries often lead to hypo-/anesthesia and neuropathic pain, impacting individuals psychologically and socially. Diagnosis involves thorough anamnesis, clinical-neurological evaluations, and radiographic imaging. Severity varies, allowing for conservative or surgical interventions. Immediate action is recommended for reversible causes, while surgical therapies like decompression, readaptation, or reconstruction yield favorable outcomes. Conservative management, utilizing topical anesthesia, capsaicin, and systemic medications (tricyclic antidepressants, antipsychotics, and serotonin-norepinephrine-reuptake-inhibitors), proves effective for neuropathic pain.

CONCLUSIONS

Traumatic nerve injuries, though common in dental surgery, often go unrecorded. Despite lacking a definitive diagnostic gold standard, a meticulous examination of the injury and subsequent impairments is crucial.

CLINICAL RELEVANCE

Tailoring treatment to each case's characteristics is essential, recognizing the absence of a universal solution. This approach aims to optimize outcomes, restore functionality, and improve the quality of life for affected individuals.

Consensus guidelines on training, diagnosis, treatment and follow-up care of trigeminal nerve injuries

The aim was to present expert-based guidelines on the management of trigeminal nerve injuries. A two-round multidisciplinary Delphi study was conducted amongst international trigeminal nerve injury experts with a set of statements and three summary flowcharts using a nine-point Likert scale (1 = strongly disagree; 9 = strongly agree). An item was deemed appropriate if the median panel score was within the range of 7-9, undecided if the score was 4-6, and inappropriate if the score was 1-3. Consensus was achieved if at least 75% of panelists scored within one range. Eighteen specialists from dental, medical, and surgical specialties participated in both rounds. Consensus was reached on most statements related to training/services (78%) and diagnosis (80%). Statements related to treatment were mainly undecided due to a lack of sufficient evidence for some of the proposed treatments. Nevertheless, the summary treatment flowchart reached consensus with a median score of eight. Recommendations on follow-up and opportunities for future research were discussed. None of the statements were deemed inappropriate. A set of recommendations and accepted flowcharts are presented; these will aid professionals involved in managing patients with trigeminal nerve injuries.

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.

A unique artificial intelligence-based tool for automated CBCT segmentation of mandibular incisive canal

OBJECTIVES

To develop and validate a novel artificial intelligence (AI) tool for automated segmentation of mandibular incisive canal on cone beam computed tomography (CBCT) scans.

METHODS

After ethical approval, a data set of 200 CBCT scans were selected and categorized into training (160), validation (20), and test (20) sets. CBCT scans were imported into Virtual Patient Creator and ground truth for training and validation were manually segmented by three oral radiologists in multiplanar reconstructions. Intra- and interobserver analysis for human segmentation variability was performed on 20% of the data set. Segmentations were imported into Mimics for standardization. Resulting files were imported to 3-Matic for analysis using surface- and voxel-based methods. Evaluation metrics involved time efficiency, analysis metrics including Dice Similarity Coefficient (DSC), Intersection over Union (IoU), Root mean square error (RMSE), precision, recall, accuracy, and consistency. These values were calculated considering AI-based segmentation and refined-AI segmentation compared to manual segmentation.

RESULTS

Average time for AI-based segmentation, refined-AI segmentation and manual segmentation was 00:10, 08:09, and 47:18 (284-fold time reduction). AI-based segmentation showed mean values of DSC 0.873, IoU 0.775, RMSE 0.256 mm, precision 0.837 and recall 0.890 while refined-AI segmentation provided DSC 0.876, IoU 0.781, RMSE 0.267 mm, precision 0. 852 and recall 0.902 with the accuracy of 0.998 for both methods. The consistency was one for AI-based segmentation and 0.910 for manual segmentation.

CONCLUSIONS

An innovative AI-tool for automated segmentation of mandibular incisive canal on CBCT scans was proofed to be accurate, time efficient, and highly consistent, serving pre-surgical planning.

Pharmacological Management of Orofacial Pain

Orofacial pain is a category of complex disorders, including musculoskeletal, neuropathic and neurovascular disorders, that greatly affect the quality of life of the patient. These disorders are within the fields of dentistry and medicine and management can be challenging, requiring a referral to an orofacial pain specialist, essential for adequate evaluation, diagnosis, and care. Management is specific to the diagnosis and a treatment plan is developed with diverse pharmacological and non-pharmacological modalities. The pharmacological management of orofacial pain encompasses a vast array of medication classes and approaches. This includes anti-inflammatory drugs, muscle relaxants, anticonvulsants, antidepressants, and anesthetics. In addition, as adjunct therapy, different injections can be integrated into the management plan depending on the diagnosis and needs. These include trigger point injections, temporomandibular joint (TMJ) injections, and neurotoxin injections with botulinum toxin and nerve blocks. Multidisciplinary management is key for optimal care. New and safer therapeutic targets exclusively for the management of orofacial pain disorders are needed to offer better care for this patient population.

Mapping out the surgical anatomy of the lingual nerve: a systematic review and meta-analysis

Objectives

Understanding the lingual nerve's precise location is crucial to prevent iatrogenic injury. This systematic review seeks to determine the lingual nerve's most probable topographical location in the posterior mandible.

Materials and Methods

Two electronic databases were searched, identifying studies reporting the lingual nerve's position in the posterior mandible. Anatomical data in the vertical and horizontal dimensions at the retromolar and molar regions were collected for meta-analyses.

Results

Of the 2,700 unique records identified, 18 studies were included in this review. In the vertical plane, 8.8% (95% confidence interval [CI], 1.0%-21.7%) and 6.3% (95% CI, 1.9%-12.5%) of the lingual nerves coursed above the alveolar crest at the retromolar and third molar regions. The mean vertical distance between the nerve and the alveolar crest ranged from 12.10 to 4.32 mm at the first to third molar regions. In the horizontal plane, 19.9% (95% CI, 0.0%-62.7%) and 35.2% (95% CI, 13.0%-61.1%) of the lingual nerves were in contact with the lingual plate at the retromolar and third molar regions.

Conclusion

This systematic review mapped out the anatomical location of the lingual nerve in the posterior mandible, highlighting regions that warrant additional caution during surgeries to avoid iatrogenic lingual nerve injuries.

Is Surgical Repair With Nerve Allograft More Cost-Effective Than Non-Surgical Management for Persistent Trigeminal Neuropathy? Initial Assessment With Markov Model

PURPOSE

Persistent trigeminal neuropathy (PTN) is associated with high rates of depression, loss of work, and decreased quality of life (QoL). Nerve allograft repair can achieve functional sensory recovery in a predictable manner; however, it bears significant upfront costs. In patients suffering from PTN, is surgical repair with allogeneic nerve graft, when compared to non-surgical therapy, a more cost-effective treatment option?

MATERIALS AND METHODS

A Markov model was constructed with TreeAge Pro Healthcare 2022 (TreeAge Software, Massachusetts) to estimate the direct and indirect costs for PTN. The model ran for 40 years with 1-year-cycles on a 40-year-old model patient with persistent inferior alveolar or lingual nerve injury (S0 to S2+) at 3 months without signs of improvement, and without dysesthesia or neuropathic pain (NPP). The 2 treatment arms were surgery with nerve allograft versus non-surgical management. There were 3 disease states, functional sensory recovery (S3 to S4), hypoesthesia/anesthesia (S0 to S2+), and NPP. Direct surgical costs were calculated using the 2022 Medicare Physician Fee Schedule and verified with standard institutional billing practices. Non-surgical treatment direct costs (follow-up, specialist referral, medications, imaging) and indirect costs (QoL, loss of employment) were determined from historical data and the literature. Direct surgical costs for allograft repair were $13,291. State-specific direct costs for hypoesthesia/anesthesia were $2,127.84 per year, and $3,168.24 for NPP per year. State-specific indirect costs included decreased labor force participation, absenteeism, and decreased QoL.

RESULTS

Surgical treatment with nerve allograft was more effective and had a lower long-term cost. The incremental cost-effectiveness ratio was -10,751.94, indicating surgical treatment should be utilized based on efficiency and cost. With a willingness-to-pay threshold of $50,000, the net monetary benefits of surgical treatment are $1,158,339 compared to $830,654 for non-surgical treatment. With a standard threshold incremental cost-effectiveness ratio of 50,000, the sensitivity analysis shows that surgical treatment would remain the preferred choice based on efficiency even if surgical costs were doubled.

CONCLUSION

Despite high initial costs of surgical treatment with nerve allograft for PTN, surgical intervention with nerve allograft is a more cost-effective treatment option when compared to non-surgical therapy.

Case report: Peripheral nerve stimulation relieves post-traumatic trigeminal neuropathic pain and secondary hemifacial dystonia

Post-traumatic trigeminal neuropathic pain (PTNP) combined with secondary dystonia are rare sequelae of orofacial injury and often do not respond to conservative treatment. The consensus on treatment for both symptoms is yet to be standardized. This study reports the case of a 57-year-old male patient with left orbital trauma who developed PTNP immediately after the injury and secondary hemifacial dystonia 7 months thereafter. To treat his neuropathic pain, we performed peripheral nerve stimulation (PNS) using a percutaneously implanted electrode to the ipsilateral supraorbital notch along the brow arch, which instantly resolved the patient's pain and dystonia. PTNP was relieved in a satisfactory manner until 18 months after the surgery, despite a gradual recurrence of the dystonia since 6 months after the surgery. To the best of our knowledge, this is the first reported case of PNS used for the treatment of PTNP combined with dystonia. This case report highlights the potential benefits of PNS in relieving neuropathic pain and dystonia and discusses the underlying therapeutic mechanism. Moreover, this study suggests that secondary dystonia occurs due to the uncoordinated integration of afferent sensory and efferent motor information. The findings of the present study indicate that PNS should be considered for patients with PTNP following the failure of conservative treatment. Secondary hemifacial dystonia may benefit from PNS upon further research and long-term assessment.

Posttraumatic Trigeminal Neuropathic Pain in Association with Dental Implant Surgery

Posttraumatic trigeminal neuropathy in association with dental implant surgery is preventable, and this should be the emphasis for all clinicians considering this treatment for a patient. Once the nerve injury and posttraumatic neuropathy with or without pain ensues, there is very little the clinician can do to reverse it and the high pain and permanency of the neuropathy will have a significant functional and psychological impact on the patient. Immediate implant removal is required, and home check should be routine for all cases. International diagnostic criteria are available and should be implemented in everyday practice.

Post-traumatic Trigeminal Neuropathy Associated With Endodontic Therapy: A Systematic Review

A painful or non-painful trigeminal nerve lesion brought on by trauma that exhibits symptoms and/or clinical evidence of trigeminal nerve dysfunction is known as painful post-traumatic trigeminal neuropathy (PTTN). In relation to this, the term post-traumatic persistent dentoalveolar pain (PDAP) is an idiopathic condition of chronic neuropathic origin that manifests as a diagnostic challenge for dental practitioners. Neuropathic pain is defined by the International Association for the Study of Pain (IASP) as "pain initiated or caused by a primary lesion or dysfunction in the nervous system." PDAP is located primarily in the teeth and jaws. This study systematically reviews how likely it is to get painful PTTN if the patient received endodontic therapy and the duration between doing root canal therapy (RCT) and getting PTTN. A systematic review was carried out using key search terms from PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) with English as the only permitted language. There were strict inclusion requirements. The 10 articles that were included showed a prevalence of an endodontic procedure anywhere from three to 48 months following post-endodontic treatment, and it mainly affects females in their mid-40s with no variation regarding the areas, whether it is in the maxilla or mandible. The lack of information about the association between RCT and PTTN led practitioners to make wrong diagnoses, which made the patient unwilling to seek further help. So, in this review, we identified some visible characteristics that can help in that process.

Misleading information before lower third molar surgery - 40 years of failing our patients?

Lower third molar removal is a common surgical procedure that, like all surgery, carries with it inherent risks. One primary risk of significance is inferior dental nerve injury, which can have a significant impact on patients' lives. Conventional consenting usually involves the generic discussion of risks of inferior dental nerve injury but without any substantive personalised risk assessment. Following the Montgomery judgement, these warnings have to be considered both inadequate and potentially misleading, as they are based on population research that is inherently flawed; pre-surgical risk assessments should be focused on the individual. This paper will consider the inadequacy of current consenting protocols and will suggest how we might offer clearer guidance to our patients when seeking valid consent for third molar surgery.

Healthcare costs of post-traumatic trigeminal neuropathy in Belgium - A retrospective analysis

The present aim was to estimate direct health care costs of patients suffering from post-traumatic trigeminal neuropathy (PTTN) and to compare the use of health care services, medications, and costs between temporary and persistent (>3 months) PTTN cohorts. A pre-existing clinical dataset of PTTN patients visiting a tertiary orofacial pain clinic in Belgium was utilized, including symptoms and quality of life measurements. Cost and resource utilization data were obtained by Belgium's largest health insurance provider for a period of 5 years after onset. Data from 158 patients was analyzed. The average cost per patient in the first year after injury was €2353 (IQR 1426-4499) with an out-of-pocket expense of 25% of the total cost. Hospitalization and technical interventions were the main drivers of cumulative costs, followed by consultation costs. For each cost category, expenditure was significantly higher in patients with persistent PTTN than in those with temporary PTTN (median 5-year total costs in persistent PTTN patients yielded €8866 (IQR 4368-18191) versus €4432 (IQR 2156-9032) in temporary PTTN, p <0.001) PTTN patients received repeated and frequent head and neck imaging (mean number of imaging investigations per patient was 10 ± 12). Medication consumption was high, with an unwarranted higher use of opioids and antibiotics in persistent PTTN patients. Within the limitations of this study, it seems there is a need for informing patients in detail on the inherent risks of nerve damage during dental and oromaxillofacial procedures. Every surgery should be preceded by a risk-benefit assessment in order to avoid unnecessary nerve damage.

Incidence, Aetiology, and Associated Fracture Patterns of Infraorbital Nerve Injuries Following Zygomaticomaxillary Complex Fractures: A Retrospective Analysis of 272 Patients

STUDY DESIGN

Retrospective study.

OBJECTIVE

Zygomaticomaxillary complex (ZMC) fractures are common facial injuries with heterogeneity regarding aetiologies, fracture types, infraorbital nerve (ION) involvement, and treatment methods. The aim of this study was to identify associations between aetiologies, fracture types, and neurological complications. Additionally, treatment methods and recovery time were investigated.

METHODS

Medical files of 272 patients with unilateral and bilateral ZMC fractures were reviewed, whose cases were managed from January 2014 to January 2019 at the Department of Oral and Maxillofacial Surgery, University hospitals Leuven, Belgium. History of ION sensory dysfunction and facial nerve motoric dysfunction were noted during follow-up.

RESULTS

ION hypoaesthesia incidence was 37.3%, with the main causes being fall accidents, road traffic accidents, and interpersonal violence. Significant predictors of ION hypoaesthesia were Zingg type B fractures (P = 0.003), fracture line course through the infraorbital canal (P < .001), orbital floor fracture (P < 0.001), and ZMC dislocation or mobility (P = 0.001).

CONCLUSION

Of all ZMC fractures, 37.3% exhibited ION hypoaesthesia. Only ZMC Zingg type B fractures (74.0%) were significantly more associated with ION hypoaesthesia. ION hypoesthesia was more likely (OR = 2.707) when the fracture line course ran through the infraorbital canal, and was less dependent on the degree of displacement. Neuropathic pain symptoms developed after ZMC fractures in 2.2% patients, posing a treatment challenge. Neuropathic pain symptoms were slightly more common among women, and were associated only with type B or C fractures. No other parameters were found to predict the outcome of this post-traumatic neuropathic pain condition.

Prognostic factors, symptom evolution, and quality of life of posttraumatic trigeminal neuropathy

ABSTRACT

Neurosensory disturbances (NSDs) caused by injury to the trigeminal nerve can affect many aspects of daily life. However, factors affecting the persistence of NSDs in patients with posttraumatic trigeminal neuropathies (PTTNs) remain largely unknown. The identification of such risk factors will allow for the phenotyping of patients with PTTNs, which is crucial for improving treatment strategies. We therefore aimed to identify the prognostic factors of NSD persistence, pain intensity, and quality of life (QoL) in patients with PTTNs and to use these factors to create a prognostic prediction model. We first performed a bivariate analysis using retrospective longitudinal data from 384 patients with NSDs related to posttraumatic injury of the trigeminal nerve (mean follow-up time: 322 ± 302 weeks). Bivariate and multivariate analyses were performed. The multivariable prediction model to predict persistent NSDs was able to identify 76.9% of patients with persistent NSDs, with an excellent level of discrimination (area under the receiver operating characteristic curve: 0.84; sensitivity: 81.8%; specificity: 70.0%). Furthermore, neurosensory recovery was significantly associated with sex; injury caused by local anesthesia, extraction, third molar surgery, or endodontic treatment; and the presence of thermal hyperesthesia. Pain intensity and QoL analysis revealed several factors associated with higher pain levels and poorer QoL. Together, our findings may aid in predicting patient prognosis after dental, oral, and maxillofacial surgery and might lead to personalized treatment options and improved patient outcomes.

Development and validation of a novel artificial intelligence driven tool for accurate mandibular canal segmentation on CBCT

OBJECTIVES

The objective of this study is the development and validation of a novel artificial intelligence driven tool for fast and accurate mandibular canal segmentation on cone beam computed tomography (CBCT).

METHODS

A total of 235 CBCT scans from dentate subjects needing oral surgery were used in this study, allowing for development, training and validation of a deep learning algorithm for automated mandibular canal (MC) segmentation on CBCT. Shape, diameter and direction of the MC were adjusted on all CBCT slices using a voxel-wise approach. Validation was then performed on a random set of 30 CBCTs - previously unseen by the algorithm - where voxel-level annotations allowed for assessment of all MC segmentations.

RESULTS

Primary results show successful implementation of the AI algorithm for segmentation of the MC with a mean IoU of 0.636 (± 0.081), a median IoU of 0.639 (± 0.081), a mean Dice Similarity Coefficient of 0.774 (± 0.062). Precision, recall and accuracy had mean values of 0.782 (± 0.121), 0.792 (± 0.108) and 0.99 (± 7.64×10^-05) respectively. The total time for automated AI segmentation was 21.26 s (±2.79), which is 107 times faster than accurate manual segmentation.

CONCLUSIONS

This study demonstrates a novel, fast and accurate AI-driven module for MC segmentation on CBCT.

CLINICAL SIGNIFICANCE

Given the importance of adequate pre-operative mandibular canal assessment, Artificial Intelligence could help relieve practitioners from the delicate and time-consuming task of manually tracing and segmenting this structure, helping prevent per- and post-operative neurovascular complications.

Post-traumatic trigeminal neuropathy: correlation between objective and subjective assessments and a prediction model for neurosensory recovery

BACKGROUND

Post-traumatic trigeminal neuropathy (PTN) can have a substantial effect on patient well-being. However, the relation between the neuropathic symptoms and their effect on psychosocial functioning remains a matter of debate. The purpose of this study was to evaluate the association between objective and subjective assessments of neurosensory function in PTN and predict neurosensory outcome using baseline measurements.

METHODS

This prospective observational cohort study included patients diagnosed with PTN at the Department of Oral and Maxillofacial Surgery, University Hospital Leuven, Belgium, between April 2018 and May 2020. Standardized objective and subjective neurosensory examinations were recorded simultaneously on multiple occasions during the follow-up period. Correlation analyses and principal component analysis were conducted, and a prediction model of neurosensory recovery was developed.

RESULTS

Quality of life correlated significantly (P < 0.05) with percentage of affected dermatome (ρ = - 0.35), the presence of brush stroke allodynia (ρ = - 0.24), gain-of-function sensory phenotype (ρ = - 0.41), Medical Research Council Scale (ρ = 0.36), and Sunderland classification (ρ = - 0.21). Quality of life was not significantly correlated (P > 0.05) with directional discrimination, stimulus localization, two-point discrimination, or sensory loss-of-function. The prediction model showed a negative predictive value for neurosensory recovery after 6 months of 87%.

CONCLUSIONS

We found a strong correlation of subjective well-being with the presence of brush stroke allodynia, thermal and/or mechanical hyperesthesia, and the size of the neuropathic area. These results suggest that positive symptoms dominate the effect on affect. In patients reporting poor subjective well-being in the absence of positive symptoms or a large neuropathic area, additional attention towards psychosocial triggers might enhance treatment outcome. The prediction model could contribute to establishing realistic expectations about the likelihood of neurosensory recovery but remains to be validated in future studies.

Signs and symptoms, quality of life and psychosocial data in 1331 post-traumatic trigeminal neuropathy patients seen in two tertiary referral centres in two countries

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.