Orofacial pain for clinicians: A review of constant and attack-like facial pain syndromes.

BACKGROUND: Primary headache syndromes such as migraine are among the most common neurological syndromes. Chronic facial pain syndromes of non-odontogenic cause are less well known to neurologists despite being highly disabling. Given the pain localization, these patients often consult dentists first who may conduct unnecessary dental interventions even if a dental cause is not identified. Once it becomes clear that dental modalities have no effect on the pain, patients may be referred to another dentist or orofacial pain specialist, and later to a neurologist. Unfortunately, neurologists are also often not familiar with chronic orofacial pain syndromes although they share the neural system, i.e., trigeminal nerve and central processing areas for headache disorders. CONCLUSION: In essence, three broad groups of orofacial pain patients are important for clinicians: (i) Attack-like orofacial pain conditions, which encompass neuralgias of the cranial nerves and less well-known facial variants of primary headache syndromes; (ii) persistent orofacial pain disorders, including neuropathic pain and persistent idiopathic facial/dentoalveolar pain; and (iii) other differential diagnostically relevant orofacial pain conditions encountered by clinicians such as painful temporomandibular disorders, bruxism, sinus pain, dental pain, and others which may interfere (trigger) and overlap with headache. It is rewarding to know and recognize the clinical picture of these facial pain syndromes, given that, just like for headache, an internationally accepted classification system has been published and many of these syndromes can be treated with medications generally used by neurologists for other pain syndromes.

Characteristics and natural disease history of persistent idiopathic facial pain, trigeminal neuralgia, and neuropathic facial pain.

OBJECTIVE: This study aimed to characterize key features, and to assess the clinical development of common nondental facial pain syndromes such as persistent idiopathic facial pain (PIFP), trigeminal neuralgia (TN), and neuropathic facial pain (NEUROP). METHODS: This is a longitudinal study in which prospective questionnaire data of patients presenting to a specialized outpatient clinic were collected from 2009 to 2019. A telephone interview was conducted with the same patients in 2020 to assess the natural disease history. RESULTS: n = 411 data sets of patients with chronic facial pain were compiled. Among these were n = 150 patients with PIFP, n = 111 patients with TN, and n = 86 patients with NEUROP. Guideline therapy had not been initiated in 38.7% (58/150; PIFP), 19.8% (22/111; TN), and 33.7% (29/86; NEUROP) patients. Of the patients with PIFP, 99.3% (149/150) had primarily consulted a dentist due to their pain syndrome. The additional telephone interview was completed by 236 out of the 411 patients (57.4%). Dental interventions in healthy teeth had been performed with the intention to treat the pain in many patients (78/94 [83.0%] PIFP; 34/62 [54.8%] TN; 19/43 [44.2%] NEUROP), including dental extractions. 11.3% (7/43) of the patients with TN had never profited from any therapy. In contrast, 29.8% (28/94) of the patients with PIFP had never profited from any therapy. Furthermore, the primary pharmaceutical therapy options suggested by national guidelines were, depending on the substance class, only considered to be effective by 13.8% (13/94; antidepressants) and 14.9% (14/94; anticonvulsants) of the patients with PIFP. CONCLUSIONS: Facial pain syndromes pose a considerable disease burden. Although treatment of TN seems to be effective in most patients, patients with PIFP and NEUROP report poor effectiveness even when following guideline therapy suggestions. In addition, unwarranted dental interventions are common in facial pain syndromes.

Oxytocin-Dependent Regulation of TRPs Expression in Trigeminal Ganglion Neurons Attenuates Orofacial Neuropathic Pain Following Infraorbital Nerve Injury in Rats.

We evaluated the mechanisms underlying the oxytocin (OXT)-induced analgesic effect on orofacial neuropathic pain following infraorbital nerve injury (IONI). IONI was established through tight ligation of one-third of the infraorbital nerve thickness. Subsequently, the head withdrawal threshold for mechanical stimulation (MHWT) of the whisker pad skin was measured using a von Frey filament. Trigeminal ganglion (TG) neurons innervating the whisker pad skin were identified using a retrograde labeling technique. OXT receptor-immunoreactive (IR), transient receptor potential vanilloid 1 (TRPV1)-IR, and TRPV4-IR TG neurons innervating the whisker pad skin were examined on post-IONI day 5. The MHWT remarkably decreased from post-IONI day 1 onward. OXT application to the nerve-injured site attenuated the decrease in MHWT from day 5 onward. TRPV1 or TRPV4 antagonism significantly suppressed the decrement of MHWT following IONI. OXT receptors were expressed in the uninjured and Fluoro-Gold (FG)-labeled TG neurons. Furthermore, there was an increase in the number of FG-labeled TRPV1-IR and TRPV4-IR TG neurons, which was inhibited by administering OXT. This inhibition was suppressed by co-administration with an OXT receptor antagonist. These findings suggest that OXT application inhibits the increase in TRPV1-IR and TRPV4-IR TG neurons innervating the whisker pad skin, which attenuates post-IONI orofacial mechanical allodynia.

First Bite Syndrome Following Carotid Endarterectomy.

A 67-year-old man with a high position carotid plaque presented with severe pain in ipsilateral parotid region several days after carotid endarterectomy (CEA). The pain occurred at the first bite of each meal and resolved as further bite. We diagnosed the pain as first bite syndrome (FBS). FBS is infrequent but known as a complication associated with parapharyngeal space surgery. The pain is characterized by sharp pain in the parotid region associated with mastication. The cause is unclear but thought to the result from sympathetic denervation of the parotid gland, followed by parasympathetic nerve hypersensitivity. Only five cases associated with carotid endarterectomy (CEA) have been reported. We should be in mind that CEA for high position plaque is one of the risk factors to cause FBS associated with CEA. Neurologists and vascular surgeons as well as otolaryngologists should all be informed FBS as one of the complications after carotid endarterectomy.

The neurosurgical treatment of craniofacial pain syndromes: current surgical indications and techniques.

Craniofacial pain syndromes are comprised of multiple pathological entities resulting in pain referred to the scalp, face, or deeper cranial structures. In a small subset of patients affected by those syndromes, pharmacological and physical therapies fail in alleviating pain. In some of those refractory patients surgical procedures aimed at relieving pain are indicated and have been adopted with variable results and safety profiles. In this review, the authors describe craniofacial pain syndromes that most commonly fail to respond to pharmacological therapies and may be amenable to tailored surgical procedures. In particular, trigeminal, glossopharyngeal, and occipital neuralgias are considered, as well as some primary headache syndromes such as cluster headache, short unilateral neuralgiform headache with conjunctival injection and tearing/short unilateral neuralgiform headache with autonomic symptoms, and migraine. Surgical techniques, including the implantation of deep brain or peripheral nerve electrodes with subsequent chronic stimulation, microvascular decompression of neurovascular conflicts, and percutaneous lesioning of neural structures are described. Finally, surgical indications, outcomes, and safety of these procedures are presented.

Acute and chronic pain in orofacial trauma patients.

Trauma or injury to the dentition and supporting tissues is associated with pain and discomfort, as expected, that may present immediately, shortly afterwards, or within a few days. Pain is an essential response to injury because it allows the organism to develop avoidance behavior to potential threats and helps the organism to avoid usage of the injured organ during the healing process. Not only does external trauma induce pain, but also essential invasive dental procedures such as extractions, dental implant insertions, root canal treatments, and oral surgeries are accompanied by similar post-surgical (post-traumatic) pain. The pain intensity after trauma varies and does not always correlate with the extent of injury. Trauma to the orofacial region or the teeth may also indirectly affect and induce pain in other orofacial structures such as the masticatory muscles, the temporomandibular joint, and even the cervical spine. In most cases, the pain will resolve as soon as healing of the affected tissue occurs or after dental and routine palliative treatment. In a limited number of cases, the pain persists beyond healing and evolves into a chronic pain state. Chronic pain in the orofacial region presents diagnostic and management challenges. Misdiagnosis or delayed diagnosis of the oral chronic pain condition may lead to unnecessary dental treatment. This article will discuss diagnosis and treatment for acute and chronic pain as well as potential mechanisms involved in the undesirable transition from acute to chronic pain.

Comparative study of shockwave therapy and low-level laser therapy effects in patients with myofascial pain syndrome of the trapezius.

The objective of the study was to compare the effects of shockwave therapy and laser therapy on pain, neck functionality, and quality of life in patients with myofascial pain syndrome of the trapezius. 61 patients (> 18 years) were randomly allocated to two treatment groups: (1) 31 patients received soft laser therapy once daily in a 3-week period for a total of 15 sessions, (2) 30 patients received shockwave therapy once in a week for 3 weeks, totalling 3 treatments. Resting pain and pain tolerance were assessed by a 100 mm visual analogue scale; functional status and quality of life were measured by specific questionnaires (Neck Disability Index, SF-36) before and after the 3-week therapy and at the 15th week follow-up visit. All measured parameters improved significantly in both groups at week 3 and week 15. Comparing the two groups, patients receiving shockwave therapy demonstrated significantly better changes in pain tolerance (mean between-group differences at visit 1-0 = 14.911, 95% CI = 2.641-27.182, mean between-group differences at visit 2-0 = 17.190, 95% CI = 4.326-30.055 in the left trapezius), neck functionality (mean between-group differences at visit 1- 0 = 0.660, 95% CI = - 1.933 to 3.253, mean between-group differences at visit 2-0 = 1.072, 95% CI = - 2.110 to 4.254), and in all domains using SF-36 QoL questionnaire. The only parameter in which the laser group showed significantly higher benefits was at week 15 for resting pain (mean between-group differences at visit 2-0 = - 1.345, 95% CI = - 14.600 to 11.910). The results of our study point to a conclusion that both laser and shockwave therapy are effective in myofascial pain syndrome, though we found shockwave therapy to be somewhat more beneficial. Clinical trial registration number NCT03436459 ( https://clinicaltrials.gov/ct2/show/NCT03436459 ).

Eagle Syndrome: An Unusual Cause Limited Mouth Opening and Surgical Management.

Eagle syndrome, defined "stylalgia," occurs when an elongated styloid process or calcified stylohyoid ligament causes dysphagia, facial pain recurrent throat pain or foreign body sensation, also associated symptoms such as neck or throat pain with radiation to the ear. The symptoms related to this condition can be confused or misdiagnosed to a wide variety of facial neuralgias. The incidence of Eagle syndrome varies among population. Usually asymptomatic, it occurs in adult patients, and can be diagnosed by physical examination and radiologically. A 30-year-old male patient presented to the maxillofacial unit of Sulaimaniyah Teaching Hospital with a complaint of pain in the right side of face interfering with mouth opening and causing deviation to the right side of mouth for 6 months duration. The elongated styloid process of the right side was resected surgically by the intra-oral approach. The patient was asymptomatic and comfortably followed up for 5 months.

A Multimodal Approach for Myofascial Pain Syndrome: A Prospective Study.

OBJECTIVE: The purpose of this study was to analyze pain intensity in patients with myofascial pain syndrome (MPS) following a multimodal rehabilitation protocol. METHODS: A prospective study was carried out following the Template for Intervention Description and Replication criteria. Patients were recruited from the rehabilitation unit of a university hospital in Spain between 2009 and 2013. Patients were included if they had a medical diagnosis of MPS in any of the following regions: cervicobrachial (n = 102), lumbosacral (n = 30), elbow (n = 14), ankle and foot (n = 10), and temporomandibular jaw (n = 1). The multimodal rehabilitation protocol included myofascial trigger point dry needling, spray and stretching, Kinesio taping, eccentric exercise, and patient education. The protocol was applied for 4 weeks (5 sessions) for the active and/or latent myofascial trigger points in each body region. Pain intensity was measured by using the visual analog scale (VAS) immediately before beginning of the study and 1 week after completion of the protocol. RESULTS: The study sample comprised 150 patients (mean ± standard deviation age, 51.5 ± 1.19 years). Statistically significant differences were obtained for reduction in pain intensity (4 ± 2.03; P = .002). Clinically relevant reductions (VAS ≥30 mm; P < .001) were obtained in 78.7% of the interventions. Four treatment sessions reduced the VAS score by 10 mm in 83.55% of the sample. There were no statistically significant differences (P = .064) for reduction in pain intensity in the different body regions. CONCLUSIONS: A multimodal rehabilitation protocol showed clinically relevant differences in the reduction in pain intensity in different body regions in patients with MPS.

An overview of common diseases of the nasal cavity and paranasal sinuses.

Diseases of the nasal cavity and paranasal sinuses are a common complaint amongst the general population and service personnel. Chronic rhinosinusitis, with or without nasal polyps, and nasal deformity leading to airway obstruction are some of the commonest ear, nose and throat (ENT) conditions encountered. However, hidden within this generally benign group of conditions are some potentially lethal problems that clinicians need to be able to recognise. This article aims to provide an overview of common conditions affecting the nose and paranasal sinuses, including fractured nasal bones, acute rhinosinusitis and its complications, and chronic rhinosinusitis. Epistaxis and sinonasal malignancies are largely outside the scope of this paper. Background information on pathogenesis will be described, along with guidance on diagnosis and management with particular stress on emergency pre-hospital treatment and indications for referral to an ENT specialist.

The Utility of the Sino-Nasal Outcome Test (SNOT) as a Treatment Outcome Measure in Nonsinogenic Facial Pain Syndrome.

INTRODUCTION: The purpose of this study was to assess the strength of correlation between the Sino-Nasal Outcome Test (SNOT) subdomains to determine which bore the greatest disease burden so that it could be used as a suitable measure of clinical response. METHODS: Prospective clinical audit of patients attending the Liverpool Multi-Disciplinary Facial Pain Clinic. The Brief Pain Inventory-Facial (BPI-F) was used as a comparator and surrogate measure of quality of life. RESULTS: Fifty patients (38 female) were reviewed, of whom 66% had midfacial segment pain. The total SNOT score was highly correlated with the BPI-F. Both the sleep function and psychological issues were the most highly correlated SNOT subdomains with the BPI-F, followed by ear-facial symptoms. The rhinologic symptom subdomain had a weak correlation with the BPI-F. The total SNOT score was most significantly correlated with the sleep function and psychological issues subdomains. CONCLUSION: This study supports the utility of the SNOT questionnaire as a measure of clinical outcome for nonsinogenic facial pain. The total SNOT score is highly correlated with the BPI-F, which has been used as a surrogate measure of quality of life. In addition, the sleep function and psychological issues subdomains are suitable variables to measure response to treatment.

[Heterozygote forms of familial Mediterranean fever can be manifested in adults as myofacial pain syndrome]. / Heterozygote Formen des familiären Mittelmeerfiebers können beim Erwachsenen als myofasziales Schmerzsyndrom imponieren.

BACKGROUND: Familial Mediterranean fever (FMF) is a disease characterized by recurrent fever, serositis, arthritis and unspecific myalgia. It is prevalent among Mediterranean people and has been shown to be associated with mutations in the Mediterranean fever (MEFV) gene which, encodes pyrin a regulatory protein of the inflammasome. As heterozygous mutations in MEFV can be associated with only mild inflammatory symptoms, such as arthralgia or chronic fibromyalgic pain, FMF may be underdiagnosed in the current diagnostic work-up of musculoskeletal diseases. METHODS: The selection of patients was carried out according to the following criteria: myofacial pain syndrome, seronegative oligoarthralgia, a slight inflammatory constellation and ethnic origin from the Mediterranean area. When these criteria were fulfilled a molecular genetic investigation was carried out RESULTS: This article presents evidence that 9 out of 12 Mediterranean patients with recurrent myofascial pain syndrome and mild inflammation revealed heterozygote mutations in the MEFV gene and 7 of these patients benefitted from treatment with colchicine. DISCUSSION: As colchicine treatment not only improved the myofascial pain but also prevented FMF-associated amyloidosis and nephropathy, differential diagnosis of fibromyalgia in patients of Mediterranean origin should include FMF and a genetic screening of the MEFV locus.

The temporal evolution of a facial pain syndrome associated with neurovascular contact: a case report.

BACKGROUND: Trigeminal autonomic cephalalgias are primary headaches characterized by unilateral pain and cranial autonomic symptoms. However, associated autonomic symptoms have also been reported in other headaches and facial pains, e.g. trigeminal neuralgia, with the clinical differentiation proving a complex task. CASE: A 54-year-old man presented with right-sided, sharp, intense facial pain in the distribution area of the trigeminal nerve. Pain duration was from seconds to a few minutes, and trigger factors included ipsilateral touching of the skin and hair. Over the next ten years, symptoms progressed and changed presentation, also displaying as right-sided, severe, orbital pain, lasting 60 to 90 minutes, with conjunctival injection and rhinorrhea. Neurological examination was normal. Numerous medications were tried with limited or no effect. In 2010, magnetic resonance imaging revealed a right-sided deviation of the basilar artery at the level of pons, creating neurovascular contact with the trigeminal nerve. Microvascular decompression was performed, and symptoms resolved within days. CONCLUSION: Differentiating between trigeminal autonomic cephalalgias and trigeminal neuralgia with autonomic symptoms can be challenging. The distinct change and evolution over time in the clinical presentation of the patient's head pain suggests a temporal plasticity of the pain in head and facial syndromes, irrespective of underlying pathoanatomic features.

Pain Part 5b: Non-Odontogenic Dysfunctional Pain.

UNLABELLED: Orofacial chronic pain provides a significant challenge to all clinicians and the patients seeking treatment for it. Due to the anatomical and regional complexities, diagnosis can be extremely difficult, and due to the lack of cross specialty training, patients will undergo a variety of treatment under different disciplines. Dysfunctional pain provides a unique challenge for patient management and requires a multidisciplinary team. CLINICAL RELEVANCE: Lack of recognition of dysfunctional chronic pain can result in inappropriate dental treatment and further damage. to the patient. Appropriate patient reassurance and referral to an orofacial pain multidisciplinary team is recommended as most of these conditions require medical management.

Use of an artificial neural network for diagnosis of facial pain syndromes: an update.

BACKGROUND: Based on a classification scheme for facial pain syndromes and a binomial (yes/no) facial pain questionnaire, we previously reported on the ability of an artificial neural network (ANN) to recognize and correctly diagnose patients with different facial pain syndromes. OBJECTIVES: We now report on an updated questionnaire, the development of a secure web-based neural network application and details of ANNs trained to diagnose patients with different facial pain syndromes. METHODS: Online facial pain questionnaire responses collected from 607 facial pain patients (395 female, 65%, ratio F/M 1.86/1) over 5 years and 7 months were used for ANN training. RESULTS: Sensitivity and specificity of the currently running ANN for trigeminal neuralgia type 1 and trigeminal neuralgia type 2 are 92.4 and 62.5% and 87.8 and 96.4%, respectively. Sensitivity and specificity are 86.7 and 95.2% for trigeminal neuropathic pain, 0 and 100% for trigeminal deafferentation pain and 100% for symptomatic trigeminal neuralgia and postherpetic neuralgia. Sensitivity is 50% for nervus intermedius neuralgia (NIN) and 0% for atypical facial pain (AFP), glossopharyngeal neuralgia (GPN) and temporomandibular joint disorder (TMJ). Specificity for AFP, NIN and TMJ is 99% and for GPN, 100%. CONCLUSIONS: We demonstrate the utilization of question-based historical self-assessment responses used as inputs to design an ANN for the purpose of diagnosing facial pain syndromes (outputs) with high accuracy.

Intermediate nerve neuralgia can be diagnosed and cured by microvascular decompression.

Here, we present a case of a 55-year-old woman with a 10-year history of hemifacial spasm accompanied by 1-month ipsilateral paroxysmal otalgia. Magnetic resonance imaging revealed the presence of vessels around the facial nerve root. Surgical exploration via suboccipital retromastoid craniotomy showed converging compression of the facial nerve root and intermediate nerve from both sides by an anterior inferior cerebellar artery loop. The patient's hemifacial spasm and ipsilateral otalgia were completely relieved after microvascular decompression of the facial nerve root and intermediate nerve. Intraoperative findings and the postoperative result of this case confirmed that vascular compression of the intermediate nerve was the exclusive cause of paroxysmal otalgia. The presence of ipsilateral hemifacial spasm, combined with preoperative neuroimaging studies, contributed to the diagnosis of intermediate nerve neuralgia. Microvascular decompression should be considered for the management of patients with intermediate nerve neuralgia.

Diagnostic role of magnetic resonance imaging in assessing orofacial pain and paresthesia.

The aim of this study was to compare the efficacy of CT and MRI in evaluating orofacial pain and paresthesia. A total of 96 patients with orofacial pain and/or paresthesia were included in this study. The patients who underwent CT and/or MRI examinations were assessed, and the efficacy of CT and/or MRI examinations in detecting the causative disease of the orofacial pain and paresthesia was evaluated. Seventy (72.9%) of 96 patients underwent CT and/or MRI examinations. Whereas CT examinations detected 2 diseases (4.5%) in 44 tests, 13 diseases (37.1%) were detected in 35 MRI examinations. Seven (53.8%) of 13 diseases, which were detected by MRI, were found in elderly patients. A high percentage of patients, who claimed orofacial pain and paresthesia, have other diseases in their brain, especially in elderly patients, and MRI is more useful than CT for evaluating these patients.

Effects of deep cervical flexor training on pressure pain thresholds over myofascial trigger points in patients with chronic neck pain.

OBJECTIVE: The purpose of this study was to assess the effects of a low-load training program for the deep cervical flexors (DCFs) on pain, disability, and pressure pain threshold (PPT) over cervical myofascial trigger points (MTrPs) in patients with chronic neck pain. METHODS: Thirty patients with chronic idiopathic neck pain participated in a 6-week program of specific training for the DCF, which consisted of active craniocervical flexion performed twice per day (10-20 minutes) for the duration of the trial. Perceived pain and disability (Neck Disability Index, 0-50) and PPT over MTrPs of the upper trapezius, levator scapulae, and splenius capitis muscles were measured at the beginning and end of the training period. RESULTS: After completion of training, there was a significant reduction in Neck Disability Index values (before, 18.2 ± 12.1; after, 13.5 ± 10.6; P < .01). However, no significant changes in PPT were observed over the MTrPs. CONCLUSION: Patients performing DCF training for 6 weeks demonstrated reductions in pain and disability but did not show changes in pressure pain sensitivity over MTrPs in the splenius capitis, levator scapulae, or upper trapezius muscles.

Orofacial Migraine and Other Idiopathic Non-Dental Facial Pain Syndromes: A Clinical Survey of a Social Orofacial Patient Group.

Background: Orofacial pain syndromes (OFPs) are a heterogeneous group of syndromes mainly characterized by painful attacks localized in facial and oral structures. According to the International Classification of Orofacial Pain (ICOP), the last three groups (non-dental facial pain, NDFP) are cranial neuralgias, facial pain syndromes resembling primary headache syndromes, and idiopathic orofacial pain. These are often clinical challenges because the symptoms may be similar or common among different disorders. The diagnostic efforts often induce a complex diagnostic algorithm and lead to several imaging studies or specialized tests, which are not always necessary. The aim of this study was to describe the encountered difficulties by these patients during the diagnostic-therapeutic course. Methods: This study was based on the responses to a survey questionnaire, administered to an Italian Facebook Orofacial Patient Group, searching for pain characteristics and diagnostic-therapeutic care courses. The questionnaire was filled out by patients affected by orofacial pain, who were 18 years and older, using a free online tool available on tablets, smartphones, and computers. Results: The sample was composed of 320 subjects (244F/76M), subdivided by age range (18-35 ys: 17.2%; 36-55 ys: 55.0%; >55 ys 27.8%). Most of the patients were affected by OFP for more than 3 years The sample presented one OFP diagnosis in 60% of cases, more than one in 36.2% of cases, and 3.8% not classified. Trigeminal neuralgia is more represented, followed by cluster headaches and migraines. About 70% had no pain remission, showing persisting background pain (VAS median = 7); autonomic cranial signs during a pain attack ranged between 45 and 65%. About 70% of the subjects consulted at least two different specialists. Almost all received drug treatment, about 25% received four to nine drug treatments, 40% remained unsatisfied, and almost 50% received no pharmacological treatment, together with drug therapy. Conclusion: To the authors' knowledge, this is the first study on an OFP population not selected by a third-level specialized center. The authors believe this represents a realistic perspective of what orofacial pain subjects suffer during their diagnostic-therapeutic course and the medical approach often results in unsatisfactory outcomes.