High prevalence of orofacial pain in juvenile fibromyalgia as detected by a novel tool specifically devised for children and adolescents.

OBJECTIVES: To examine the prevalence of temporomandibular disorders (TMD) in patients with juvenile fibromyalgia syndrome (JFS) and identify TMD characteristics specifically associated to JFS. METHODS: Signs and symptoms of TMD were assessed using a novel clinical tool specifically devised for children that consists of: 1. a self-report multiple-choice questionnaire; 2. a protocol for the clinical examination of the orofacial region. Multivariate logistic regression model was used to identify TMD features associated with JFS. RESULTS: Thirty JFS patients (median age 15.5 years) and 45 healthy controls (median age 15.0 years) were included in this cross-sectional study. Orofacial pain was reported by 26 of 30 JFS patients (86.7%) and by 3 of 45 controls (6.7%; p<0.001). Pain on TMJ palpation was present in 18 of 30 JFS patients (60%) and in 5 of 45 controls (11.1%; p<0.001). Median values of maximum spontaneous mouth opening, voluntary active opening and assisted passive opening were significantly higher in JFS patients than in controls. On multiple regression analysis spontaneous orofacial pain (OR: 21.0; p=0.005), diffuse tenderness on palpation of the masticatory muscles (OR: 14.9; p=0.026) and TMJ hypermobility (OR 1.42; p=0.008) were independently associated with JFS. CONCLUSIONS: The high prevalence of TMD in JFS highlights the need for a broader interdisciplinary evaluation of JFS patients. TMJ hypermobility, in addition to orofacial and masticatory muscle pain, is an important clue for the diagnosis of TMD in adolescents with JFS. Elucidating the link between these disorders will advance individualised management and improve treatment efficacy.

Pregnancy related factors and temporomandibular disorders evaluated through the diagnostic criteria for temporomandibular disorders (DC/TMD) axis II: a cross sectional study.

INTRODUCTION: Temporomandibular disorder (TMD) is a multifaceted condition impacting the chewing system, with its frequency varying across different age groups and showing a higher incidence in women. The involvement of estrogen in TMD has been examined due to the presence of estrogen receptors in the TMJ area. However, the exact effect of estrogen on TMD is complex. During pregnancy, marked by significant hormonal fluctuations, the impact on TMD has been hypothesized but remains unclear due to inconsistent results from various studies. METHODS: In this cross-sectional study, we enrolled 32 pregnant women consecutively. We gathered information on demographics, TMD evaluations (using the Graded Chronic Pain Scale, Jaw Functional Limitation Scale-20, and Oral Behaviors Checklist), and mental health assessments (including Patient Health Questionnaire-9, Patient Health Questionnaire-15, and Generalized Anxiety Disorder-7). We employed descriptive statistics to summarize continuous and categorical data and used t-tests and chi-square tests for comparisons. We also conducted multivariate linear regression, adjusted for demographic factors, to investigate correlations. RESULTS: The study group mainly consisted of women aged 30-35 (40.6%) and 25-30 (18.8%). Most participants had completed high school (50%) and were married (71.9%). A notable association was found between younger women (under 30) and higher levels of somatic symptoms (p = 0.008) and generalized anxiety (p = 0.015). Women in their second trimester showed lower severity of somatic symptoms (p = 0.04). A significant link was also observed between depression severity and somatic symptom severity (p = 0.01). However, we found no significant correlations with other TMD-related health aspects. DISCUSSION: Our study identified significant associations between psychosomatic and psychological symptoms with variables like age and pregnancy trimester in pregnant women. However, it notably failed to establish a clear relationship between pregnancy-related factors and the severity of temporomandibular disorders (TMD). More comprehensive studies with larger participant pools are necessary to further validate and expand these findings.

Effects of physical activity levels on characteristic pain in temporomandibular dysfunctions: a cross-sectional study.

BACKGROUND: Physical activity is known to influence the symptoms of a variety of pain disorders including fibromyalgia and osteoarthritis although the underlying mechanism is not fully understood. In spite of the high prevalence of temporomandibular disorders (TMD), no previous study has objectively evaluated the relationship between TMD and general physical activity. This study aims to investigate the influence of physical activity on pain and disability from TMD, considering various confounders including sleep, systemic inflammation, psychosocial disturbances, and widespread pain. METHODS: This observational cross-sectional study is based on consecutive samples of 100 TMD patients (22 with high pain disability and 78 with low pain disability level). Physical activity levels were assessed with actigraph. Level of pain and disability were evaluated using the Graded Chronic Pain Scale. Hematologic examinations including inflammatory biomarkers were assessed and comorbidities were investigated with validated questionnaires. Differences were analyzed according to disability level. RESULTS: Patients with high disability level spent significantly more time doing both moderate (p = 0.033) and vigorous (p = 0.039) level physical activity. Light physical activity, on the other hand, was associated with low disability but the difference did not reach statistical significance. Time spent in light physical activity was significantly associated with high levels of pain and disability (p = 0.026, ß = -0.001) and time spent in vigorous physical activity had significant predictive power (cutoff value 2.5 min per week, AUC 0.643, p = 0.041). Scores of the Jaw Function Limitation Score-20 (p = 0.001), present McGill Pain Score (p = 0.010), and number of people potentially diagnosed with fibromyalgia (p = 0.033) were significantly higher in the high disability group. CONCLUSIONS: Moderate or vigorous physical activity is associated with worse TMD symptoms while light physical activity may be beneficial. Further research related to the amount and frequency of physical activity is necessary to establish clinical guidelines for TMD. TRIAL REGISTRATION: clinical trial registration of the Clinical Research Information Service of Republic of Korea (number KCT0007107).

Predictors of Non-Rhinogenic Facial Pain or Pressure in Otolaryngology Clinic.

OBJECTIVES: Identify demographic and clinical characteristics that may help differentiate non-rhinogenic facial pain or pressure (NRFP) from sinusitis. STUDY DESIGN: Retrospective single-institution study. SETTING: Tertiary Care Center Rhinology Clinic. METHODS: All patients presenting with a complaint of facial pain or pressure over a 3-year period were included. Patients were categorized into either NRFP or sinusitis groups based on computed tomography imaging and nasal endoscopy. Data pertaining to demographics, history, and SNOT-22 questionnaire domains were compared via univariate analysis as well as logistic regression with backwards variable selection. RESULTS: A total of 296 patients met inclusion criteria, of which 128 had NRFP and 168 had sinusitis. A significantly greater percentage of patients in the NRFP group were women of childbearing age (40.6% vs 28.0%, P = .02). Backwards variable selection resulted in a model with four variables predicting a diagnosis of NRFP-female sex (odds ratio [OR] = 2.998, P < .0001), no history of prior sinonasal surgery (OR = 0.340 for history vs no history, P < .01), low nasal domain score (OR = 0.551, P < .0001), and high ear/facial domain score (OR = 1.453, P < .01). CONCLUSION: Accurately identifying patients with NRFP at initial presentation based on history would help direct patients to the appropriate care pathway and prevent ineffective treatments such as antibiotics and sinus procedures. Our findings suggest that the suspicion for NRFP should be higher in women of child-bearing age as well as patients with greater ear/facial symptoms or lesser nasal symptoms.

Lymphoma masquerading as jaw pain, headache, and syncope: A case report.

BACKGROUND: Lymphomas of parapharyngeal space often have complex manifestations, posing a diagnostic dilemma for clinicians. CASE DESCRIPTION: A 64-year-old man sought treatment for a 4-month history of unresolving right-sided headache and jaw pain associated with syncope, all of which started with a toothache. Since the onset of pain, the patient had undergone multiple diagnostic tests with various specialists, with no pain relief. A detailed clinical and radiologic examination by an orofacial pain specialist revealed diffuse large B-cell lymphoma in the parapharynx. PRACTICAL IMPLICATIONS: A thorough knowledge of the head and neck anatomy helps in identifying the pathophysiology of complex orofacial pain manifestations, which assists in early diagnosis and treatment.

A rare case of vestibular schwannoma manifesting as trigeminal neuralgia.

BACKGROUND: In this case report, the authors reviewed a rare case of a vestibular schwannoma manifesting as trigeminal neuralgia (TN). Intracranial tumors can have a variety of orofacial pain symptoms. Among benign cerebellopontine angle tumors, vestibular schwannoma is the most common cause of a TN-like manifestation. Although the most common symptoms of a vestibular schwannoma are hearing loss and vestibulopathy, the unique feature of this case was the manifestation of symptoms consistent with TN. CASE DESCRIPTION: The patient had right-sided episodic facial pain that was short in duration and severe in intensity. The initial differential diagnoses included short-lasting, unilateral, neuralgiform headache attacks with conjunctival injection and tearing and TN. As part of the routine evaluation, the patient was referred for brain magnetic resonance imaging, which revealed a right-sided vestibular schwannoma. The patient was prescribed 200 mg of gabapentin 3 times daily and was referred to neurosurgery for excision of the schwannoma. Surgical excision resulted in complete resolution of pain. PRACTICAL IMPLICATIONS: This case illustrates the importance of interdisciplinary treatment and how it can lead to an optimal outcome for a patient with complex orofacial pain symptoms.

Orofacial Pain and Risk of Dysphagia in Women With Fibromyalgia: A Cross-Sectional Observational Study.

OBJECTIVE: This study aims to analyze the frequency of dysphagia risk and swallowing-associated quality of life (QoL) in a sample of women with fibromyalgia syndrome (FMS) and examine the potential relationship between risk of dysphagia and chronic orofacial pain (COP) in a sample of women with FMS. METHOD: A cross-sectional observational study was conducted in 46 women with FMS. COP was assessed by mouth opening, the orofacial visual analog scale (VAS), and the craniofacial pain and disability inventory (CF-PDI). Risk of dysphagia was assessed using the Eating Assessment Tool (EAT-10) and the volume-viscosity swallowing test (V-VST). Swallowing-associated QoL was determined using the Swallowing Quality of Life (SWAL-QOL) questionnaire. RESULTS: Thirty patients were identified as being at risk for dysphagia (65.21%) using the EAT-10 and, according to the SWAL-QOL, 41.30% of patients had alterations in QoL associated with swallowing. The EAT-10 correlated positively with orofacial VAS, CF-PDI-total, CF-PDI-pain and disability, and CF-PDI-jaw-functional status. In relation to SWAL-QOL, negative correlations were observed for orofacial VAS, CF-PDI-total, CF-PDI-pain and disability, and CF-PDI-jaw-functional status. Patients at risk of dysphagia (EAT-10 and V-VST) had significantly higher scores in orofacial VAS (p = .002 and p = .015), CF-PDI-total (p = .006 and p = .014), and CF-PDI-pain and disability (p = .004 and p = .013). CONCLUSIONS: In this sample of women with FMS, we identified a high rate of dysphagia risk. Also, a high percentage of these women presented alterations in QoL associated with swallowing. Patients at risk for dysphagia had significantly higher orofacial VAS and CF-PDI-total scores, supporting the relationship between dysphagia risk and COP in FMS. Further research to establish the need for appropriate assessment referrals in clinical practice to determine whether dysphagia is present in this population is needed.

Ketamine for atypical facial pain and hormonal dysregulation: a case report.

BACKGROUND: Ketamine has garnered increased interest for its promising applications in chronic pain treatment, particularly in cases where conventional therapies have proven insufficient. Nevertheless, despite its potential advantages, ketamine remains classified as a third-line medication for pain management. While there are well-documented reactions to ketamine such as hypertension and tachycardia, not much is known about its relationship to cortisol. In this case report, we explicate the administration of ketamine in a patient presenting with atypical facial pain, examining its multifaceted effects on cortisol levels and concurrent pain management. CASE PRESENTATION: A patient with a history of Cushing's disease underwent multiple resections of a pituitary tumor. Afterwards, the patient began experiencing a burning-like pain on the left side of the face. The discomfort was initially treated with a variety of neuromodulatory and anti-inflammatory medications, which caused intolerable side effects and were not effective for pain. As a final recourse, we initiated a regimen of oral compounded ketamine at 5-10 mg three times daily as needed. The patient exhibited marked amelioration in their pain symptoms; however, there was an elevation in their baseline cortisol. In view of the potential risk of inducing Cushing's syndrome, the administration of daily ketamine was discontinued. CONCLUSION: While ketamine is primarily known to control pain through the antagonization of N-methyl-D-aspartate receptors, its effects on cortisol may also contribute to its analgesic properties. Physicians should be aware of the potential for these interactions, particularly when treating patients with a predisposition to hormonal imbalances.

Pathogenesis and Differential Diagnosis of Temporomandibular Joint Disorders.

Temporomandibular disorders (TMDs) are an umbrella term including disorders of the temporomandibular joint and muscles of the masticatory system. They are the most common nonodontogenic cause of pain in the orofacial region. A clear understanding of various conditions, underlying mechanisms, clinical presentation, and examination skills is required to effectively diagnose and manage these patients.

Temporomandibular disorders-review of evidence-based management and a proposed multidisciplinary care pathway.

Temporomandibular disorders (TMDs) are a prevalent but complex group of conditions that cause orofacial pain. Temporomandibular disorders are recognized as one of the most common chronic pain conditions, alongside back pain and headache disorders. Given the competing theories surrounding what causes TMDs and limited high-equality evidence on optimally treating TMDs, clinicians often encounter challenges in developing an effective management plan for patients. Furthermore, patients will often seek advice from multiple health care providers from varying specialties, seeking curative management, often resulting in inappropriate treatments and no improvement in pain symptoms. Throughout this review, we explore the existing evidence base surrounding the pathophysiology, diagnosis, and management of TMDs. An existing United Kingdom-based multidisciplinary care pathway for the management of TMDs is described herein, highlighting the benefits of a multidisciplinary approach to patient care for TMDs.

Diagnosis and treatment of intractable idiopathic orofacial pain with attention-deficit/hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) has been reported to be associated with primary chronic pain syndromes, such as fibromyalgia, migraine, and chronic low back pain. Although idiopathic orofacial pain (IOP) is classified as burning mouth syndrome or persistent idiopathic facial or dentoalveolar pain and as a primary chronic pain, the association between IOP and ADHD has not been investigated. This retrospective cohort study investigated the severity of ADHD symptoms measured using the ADHD scale and the effects of treatment using ADHD drugs and the dopamine system stabilizer aripiprazole. The participants were 25 consecutive patients with refractory IOP referred to a psychiatrist and diagnosed with coexisting ADHD according to the Diagnostic and Statistical Manual of Mental Disorders-5. The ADHD scale scores were higher in patients with intractable IOP than those in the general population. Pharmacotherapy used in this study led to clinically significant improvements in pain, anxiety/depression, and pain catastrophizing. Intractable IOP and ADHD were shown to be associated. In the future, screening and pharmacotherapy for ADHD should be considered in the treatment of intractable IOP.

Pathology Mimicking Orofacial Pain.

A case of a 64-year-old woman is reported, who developed new-onset pain over a preexisting area of right mandibular fullness. Clinical examination, MRI, and fine-needle aspiration cytology confirmed the diagnosis of a benign parotid gland tumor-pleomorphic adenoma, which was treated by total parotidectomy with complete removal of the tumor. When evaluating a patient with orofacial pain, oral health care providers should be cognizant of all potential differential diagnoses, especially in the setting of red flags such as persistent or enlarging facial swelling/fullness.

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.

Investigation of temporomandibular disorders in patients with fibromyalgia syndrome: A case-control study.

INTRODUCTION: The aim of this study is to compare the frequency of temporomandibular disorders and to examine the temporomandibular pain and functionality levels between healthy female participants and female patients diagnosed with fibromyalgia. MATERIALS AND METHODS: Our study included 300 participants. Patients were evaluated according to the Diagnostic Criteria for Temporomandibular Disorders: Assessment Instruments (DC/TMD). While evaluating the patients using DC/TMD, TMD Pain Screener and Symptom questionnaire were used within the scope of Axis I, and Graded Chronic Pain Scale, Jaw Functional Limitation Scale-8 (JFLS-8), Patient Health Questionnaire (PHQ-4) and Oral Behaviors Checklist were applied. RESULTS: Bruxism, tooth grinding and masseter hypertrophy were found to be significantly higher in fibromyalgia patients compared to healthy volunteers (p<0.001). The pain screener, JFLS-8, PHQ-4 and OBC scores and GCPS levels were found to be increased in the fibromyalgia group compared to healthy individuals (p<0.001). Considering the post-examination diagnoses of the participants, the diagnoses of myalgia (p=0.022) and disc displacement with reduction (p<0.001) were significantly higher than healthy individuals. CONCLUSIONS: Fibromyalgia is a common pathology, therefore, TMD symptoms, which are more difficult to diagnose and often missed, should be questioned in fibromyalgia patients and should be kept in mind in the management of fibromyalgia patients.

Reconsideration of hyoid bone syndrome-A case series with a review of the literature.

BACKGROUND: Hyoid bone syndrome is a type of faciocervical pain and occasionally concomitant clicking larynx that is caused by degeneration and/or elongation of the greater horn of the hyoid bone at the attachment of the stylohyoid ligament. CASES PRESENTATION: We report five patients who presented with deep-seated, dull, aching, throat pain that radiated from neck, accompanying by throat clicking while speaking, swallowing, yawning, and turning head. Most notably, one of them also complained an intermittent ulcer hemorrhage in the tongue base. Diagnostic tests included physical palpation of the hyoid greater cornu and computed tomography examination. One patient did not accept the surgery, but other than that four patients responded well to resection of the abnormal hyoid bone, which resulted in immediate and complete relief of their symptoms and with no postoperative complications. CONCLUSIONS: Clicking sensation and pain while deglutition is an unpleasant condition, which produces physiological and psychological bearings. This dictates the need for accurate diagnosis and proper management of the condition. Oral and maxillofacial surgeons involved in the treatment of orofacial pain should consider this rare condition as a differential diagnosis.

Association of climacterium with temporomandibular disorders at the age of 46 years - a cross-sectional study.

OBJECTIVE: Hormonal factors have been suggested to contribute to female dominance among subjects with temporomandibular disorders (TMD). Aim of the study was to examine the association of climacteric status with TMD amongst female participants in the Northern Finland Birth Cohort (NFBC) 1966 at 46 years of age. MATERIAL AND METHODS: Among female subjects in NFBC1966, climacteric status was determined based on menstrual anamnesis and measurement of blood follicle-stimulating hormone (FSH) levels. Women with FSH > 25 IU/L and amenorrhoea > 4 months were defined as climacteric (case group, n = 71); women not diagnosed as climacteric were defined as preclimacteric (control group, n = 656). Differences between cases and controls were evaluated on self-reported TMD pain, clinical TMD signs and TMD diagnoses using modified Diagnostic Criteria for TMD (DC/TMD) protocol. Crosstabulation and logistic regression models were used to analyse differences between cases and controls. RESULTS: Compared to preclimacteric women, climacteric women had significantly more often pain on palpation in temporomandibular joints (TMJs) (OR = 2.64, 95% CI 1.12-6.21, p= .026) and more crepitus in TMJs (OR = 2.92, 95% CI 1.13-7.56, p= .027). Degenerative joint disease diagnoses were more common in climacteric than preclimacteric women (OR = 2.27, 95% CI 1.05-4.91, p= .037). Differences were statistically significant after adjusting for confounding factors (body mass index (BMI), smoking, parity). No statistically significant differences in self-reported TMD pain were noted between groups. CONCLUSION: Among females at the age of 46 years, climacterium seems associated with TMD by increasing pain on palpation in TMJs, subjective symptoms, and clinical signs indicating degenerative changes in TMJs when using DC/TMD.

Diagnosis and treatment of Eagle's syndrome and possible complications.

BACKGROUND: Eagle's syndrome (ES) is a term describing a group of symptoms associated with the elongation of the styloid process (SP) of the temporal bone or with ossification of the stylohyoid ligament. Clinically, it manifests through pain in the orofacial and pharyngeal regions, similar to that experienced by patients with temporomandibular joint disease. The presented paper aims to assess the evaluation of the success of surgical treatment and the complications associated with such treatment. METHODS: Our retrospective study includes nine patients with ES treated in our Department Oral and Maxillofacial Surgery in years 2019-2023 (median age of 47 years) - all patients affected with this disease out of 2,716 patients examined at our department due to a temporomandibular joint disease. Eight of these patients underwent a surgical resection of the SP. The success and complications in these patients are evaluated in this study. RESULTS: In seven patients, the problems disappeared or at least diminished, which is consistent with data from the literature. Postoperative complications such as deficit of the marginal branch of the facial nerve (n. VII), limited sticking the tongue out (n. XII), and velopharyngeal insufficiency (n. IX) occurred in three patients. CONCLUSION: The wide spectrum of clinical manifestations makes ES a condition that should be considered in the differential diagnosis of temporomandibular joint disorders, post-traumatic conditions, or complicated eruption of wisdom teeth or their extraction. ES can be treated conservatively or (mostly) surgically. Surgical treatment can be relatively successful and effective, but it is necessary to respect the anatomical placement of the SP, which can be associated with the development of complications, especially in cases with extremely long SP.

Differential diagnosis of temporomandibular disorders - a review of the literature.

Pain in the masticatory muscles or temporomandibular joints may in some cases be a symptom of other afflictions occurring in this region. The aim of the study was to present the differential diagnosis of temporomandibular disorders (TMD) and other diseases in the craniofacial area, based on review of the literature. Using the key words: "differential diagnosis of TMD", "pain of non-dental origin" and "chronic orofacial pain", PUBMED and Scopus databases were systematically searched for articles in English from 2005 to 2020. Additionally, the PUBMED database was supplementarily reviewed using the keywords "Lyme disease orofacial symptoms" for the English-language articles published in the years 1996-2020. Out of 445 publications from PUBMED and Scopus databases as well as other sources, 57 articles describing the pathogenesis and characteristic symptoms of diseases that may cause pain similar to that occurring in TMD as well as diagnostic methods used in differential diagnosis of TMD were selected for analysis. Dental and jawbones-related conditions, ear and maxillary sinus diseases, as well as ailments of neuropathic and vascular origin, were taken into account. Neoplastic processes taking place in this region and less often occurring diseases caused by viruses, bacteria and parasites were also described. Conclusions. Correct diagnosis of temporomandibular disorders is based on medical history and thorough physical examination, as well as results of additional tests. Pain localized in the head and neck structures may have diverse, sometimes complex aetiology, and may require multidisciplinary treatment. Observation of the patient's behaviour and - in selected cases - the results of additional laboratory tests, also play a significant role.

Characteristics and prevalence of orofacial pain as an initial symptom of oral and oropharyngeal cancer and its impact on the patient's functionality and quality of life.

OBJECTIVE: To evaluate the prevalence and characteristics of orofacial pain in oral and oropharyngeal cancer (OOC), at diagnosis. MATERIAL AND METHODS: a) Study group (SG; n = 74) patients with cancer were divided into 2 subgroups: oral cancer (OC) and oropharyngeal cancer (OPC); b) control group (CG; n = 74) patients within dental care. STUDY DESIGN: An Orofacial Pain Assessment, verbal descriptive scale, Helkimo dysfunction index, Quality of Life questionnaire, and Karnofsky performance status (KPS) was used for evaluation. RESULTS: The mean age was 58.46 years (79.7% male) in SG, 58.61 years (20.3% male) in CG. The pain within the SG was indicated by the following: prevalence = 91.9% (21.6% in stages 0, I, or II; 70.3% in III or IV); reason for seeking care = 50.1%; main complaint = 55.4%; most important issue in the past 7 days = 74.3%; breakthrough-like pain = 64.9%; main features: chewing or swallowing as triggering factors, wake up patient, variable duration, independent of daytime, multiple descriptors, and earache. The following indexes were worse within the SG: clinical dysfunction, quality of life, and KPS. In addition, the OC subgroup reported toothache-like pain and burning; whereas the OPC subgroup reported heavy swallowing as triggering factor, throat as location, and a bilateral earache. CONCLUSION: At diagnosis, orofacial pain, including breakthrough-like pain, was prevalent in patients with OOC, and the pattern was heterogeneous. Predominantly, the pain was moderate to severe, related to stage of cancer, and already compromising the patients' quality of life and functionality.

Assessment of Nerve Injury-induced Mechanical Hypersensitivity in Rats using an Orofacial Operant Pain Assay.

Pain has sensory and affective components. Unlike traditional, reflex-based pain assays, operant pain assays can produce more clinically relevant results by addressing the cognitive and motivational aspects of pain in rodents. This paper presents a protocol for assessing mechanical hypersensitivity following chronic constriction injury of the infraorbital nerves (CCI-ION) in rats using an orofacial operant pain system. Before CCI-ION surgery, rats were trained in an orofacial pain assessment device (OPAD) to drink sweetened condensed milk while making facial contact with the metal spiked bars and lick-tube. In this assay, rats can choose between receiving milk as a positive reinforcer or escaping an aversive mechanical stimulus that is produced by a vertical row of small pyramid-shaped spikes on each side of the reward access hole. Following 2 weeks of training in the OPAD and before the CCI-ION surgery, baseline mechanical sensitivity data were recorded for 5 days for each rat during a 10 min testing session. During a session, the operant system automatically records the number of reward bottle activations (licks) and facial contacts, contact duration, and latency to the first lick, among other measures. Following baseline measurements, rats underwent either CCI-ION or sham surgery. In this protocol, mechanical hypersensitivity was quantified by measuring the number of licks, latency to the first lick, the number of contacts, and the ratio of licks to facial contacts (L/F). The data showed that CCI-ION resulted in a significant decrease in the number of licks and the L/F ratio and an increase in the latency to the first lick, indicating mechanical hypersensitivity. These data support the use of operant-based pain assays to assess mechanical pain sensitivity in preclinical pain research.