Common Orofacial Pain Research Articles

Attention-deficit hyperactivity disorder and psychostimulant use in patients seeking dental care-Associations with common orofacial pain complaints.

Dental medicine should expand its scope to properly assess medical and psychosocial factors that might have an impact on patients' oral health. Based on previous literature and clinical experience, attention-deficit/hyperactivity disorder and psychostimulant medications might represent factors associated with orofacial pain symptoms. The aim of the study was to assess whether common orofacial pain complaints such as jaw pain, jaw clicking, teeth clenching and headaches are more prevalent in dental patients who have an ADHD diagnosis and/or use psychostimulant medications. Orofacial pain symptoms prevalence was compared among four groups from a sample of new patients seeking dental care at Tufts University School of Dental Medicine (n = 11 699) based on ADHD diagnosis and psychostimulants intake: G1: no ADHD, no stimulants; G2: yes ADHD, yes stimulants; G3: yes ADHD, no stimulants; G4: no ADHD, yes stimulants. In multivariable logistic regression models adjusting for age, gender, tobacco use, and alcohol consumption, significant differences were found for clenching (p < .0001), jaw pain (p < .0001), and headache (p < .0001). Compared to G1, two groups (G2 and G4) exhibited significantly higher odds of clenching and headaches, whereas only G2 exhibited significantly higher odds of jaw pain. In comparison with patients without ADHD and not taking psychostimulants medications, dental patients using psychostimulants with and without ADHD diagnosis report headaches and teeth clenching more frequently, while jaw pain is reported more frequently only by those taking psychostimulants with an ADHD diagnosis. Further research is necessary to assess the nature of these associations and their clinical relevance.

Non-invasive evaluation of vascular permeability in formalin-induced orofacial pain model using infrared thermography

Enhanced vascular permeability at the site of injury is a prominent feature in acute inflammatory pain models, commonly assessed through the Evans Blue test. However, this invasive test requires euthanasia, thereby precluding further investigations on the same animal. Due to these limitations, the integration of non-invasive tools such as IRT has been sought. Here, we aimed to evaluate the use of thermography in a common orofacial pain model that employs formalin as a chemical irritant to induce local orofacial inflammation. Male Hannover rats (290–300 g, N = 43) were used. In the first approach, radiometric images were taken before and after formalin administration, assessing temperature changes and extravasated Evans Blue. The second approach included capturing pre- and post-formalin test radiometric images, followed by cytokine measurements in excised vibrissae tissue. Rats were anesthetized for vibrissae tissue collection, allowing correlations between thermographic patterns, nocifensive behavior duration, and cytokine levels in this area. Our findings revealed a positive correlation between local temperature, measured via thermography, and vascular permeability in the contralateral (r2 = 0.3483) and ipsilateral (r2 = 0.4502) side, measured using spectrophotometry. The obtained data supports the notion that thermography-based temperature assessment can effectively evaluate vascular permeability in the orofacial region.

Effectiveness of exercise therapy on pain relief and jaw mobility in patients with pain-related temporomandibular disorders: a systematic review.

Orofacial pain conditions are complex disorders that involve biological, social, and psychological factors. Temporomandibular Disorders (TMDs) are one of the most common orofacial pain conditions, and our previous literature review indicated that exercise therapy has shown promise in reducing TMD-related pain. However, more evidence is needed to firmly establish its effectiveness. This systematic review aims to investigate the effectiveness of exercise therapy on pain relief and jaw mobility in patients with pain-related TMDs. To include randomized controlled trials (RCTs) written in English, a literature search was performed using PubMed, Scopus, Web of Science, Cochrane Library, Ovid, EBM reviews, and Academic Search Complete initially from 4th November 2020 until March 2022. A PICOS for this review was as follows; P: Patients with TMD myalgia or arthralgia, I: Excursion exercise, Stretch exercises, Resistance exercise, or Coordination exercise, C: No treatment or education only. O: Pain intensity and Range of Motion (ROM), S: RCTs. After title screening, a full-text assessment was done to extract data. According to Risk of Bias (RoB) 2.0, risk of bias was assessed in each included paper by 2 reviewers independently. A total of 3,388 titles were identified from the electronic database search. After the screening and full-text evaluation, only 5 studies (145 participants) were eligible to be included. Among the exercise modalities, coordination exercise showed a significant effect on pain relief and improvement of joint mobility. Due to the heterogeneity and small sample size of the included studies, a meta-analysis was not feasible. However, this systematic review suggested that exercise therapy, especially coordinate exercise, can be effective in managing painful TMD conditions. Further research is needed to establish optimal parameters for this patient population, as well as standardization and consistency in terminology and treatment structure.

Topical review- salivary biomarkers in chronic muscle pain.

Muscle related temporomandibular disorders (myogenous TMD), one of the most common orofacial pain conditions, is characterized by facial pain and often accompanied by jaw movement limitations. Although the underlying biological mechanisms are still unclear, a cluster of proteins and peptides is assumed tobe involved in the pathophysiology. These proteins andpeptides may be measured in a simple non-invasive saliva sample. This work investigated whether saliva can be used to sample algogenic substances that can serve asmolecular biomarkers for TMD myalgia. Saliva and blood samples were collected from healthy individuals (n=69) and patients diagnosed with TMD myalgia (n=39) according to the Diagnostic Criteria for TMD. Unstimulated and stimulated whole, parotid, and sublingual saliva were analysed. The protein profiles were investigated using two-dimensional gel electrophoresis followed by identification with liquid chromatography tandem mass spectrometry. Levels of nerve growth factor (NGF), calcitonin gene-related peptide (CGRP), and brain derived neuro-tropic factor (BDNF) were determined using western blotting based technology and multiplex electro-chemiluminescence assay panel. Glutamate, serotonin, and substance p (SP) were determined using commercially available methods. Different saliva collection approaches resulted insignificant differences in the protein profile as well as inthe expression of NGF, BDNF, CGRP, SP, and glutamate. Stimulated whole saliva showed least variability in protein concentration (35%) and was correlated to plasma levels ofglutamate. Unlike SP and glutamate, NGF and BDNF expressed a rhythmic variation in salivary expression withhigher levels in the morning (p<0.05). Patients with a diagnosis of TMD myalgia had significantly higher levels of salivary glutamate but lower salivary NGF and BDNF compared to controls; in addition, the lower NGF and BDNF levels correlated to psychological dysfunction. Thequantitative proteomics data revealed 20 proteins that were significantly altered in patients compared to controls. The identified proteins are involved in metabolic processes, immune response, and stress response. Dissimilarities in protein profile and clinical variables were observed between TMD myalgia and myofascial pain. The work highlights the importance of consistency in saliva collection approaches, including thetiming of the collection. It displayed significant changes in pain specific mediators and protein profile in TMD myalgia and furthermore dissimilarities between subclasses indicating different pathophysiology. After extensive validation, potential salivary biomarkers can becombined with clinical features to better understand and diagnose TMD myalgia.

Correlation between Clinical Pain in Temporomandibular Disorders and Signal Intensity of the Retrodiscal Tissue Using Fluid Attenuation Inversion Recovery MRI – A Cross Sectional Study

Temporomandibular disorders (TMD) is a broad term referring to pain and dysfunction of temporomandibular joint (TMJ), nmasticatory muscles and its associated structures. TMD is the most common orofacial pain condition with prominent feature like regional pain in the face and preauricular area during static and dynamic movements. Methods of assessing clinical pain were subjective and not affirmative. There still remains element of drafting the clinical pain evaluation in TMD patients. This study correlated the pain range in TMD patients with the levels of signal intensity (SI) in FLAIR MRI (Fluid Attenuation Inversion Recovery magnetic resonance imaging) to devise an objective pain assessing system based on the SI values. Settings and design: The present study is institution based, observational cross sectional study. A 32 temporomandibular joints were evaluated in the study. Before imaging, subjective pain score were recorded using Visual Analog Scale (VAS). In FLAIR MRI, both grey matter and retro discal tissue were included in the Region of Interest and the SIRs were calculated. SIRs in painful temporomandibular joints were correlated with Visual Analog Scale score. Unpaired t test was used to compare the mean values recorded for SIR. P-value &lt;0.05 is considered to be statistically significant. Study results shows that SIRs of retrodiscal tissue were significantly increased in patient with higher VAS score (p&lt;0.05). Retrodiscal tissue in painful proteinous elements. Keywords: Temporomandibular disorders, Signal intensity, FLAIR MRI, Retrodiscal tissue

Orofacial pain disorders: An overview and diagnostic approach

Background: Non-dental orofacial pain disorders are not uncommon, but idiopathic or primary facial pain syndromes are rare. Inadequate recognition of these disorders usually leads to unsatisfactory and unmet treatment needs. Methods: We conducted a narrative review with a literature search in PubMed until December 2021, focusing on current guidelines and the recently published International Classification of Orofacial Pain (ICOP). Results: In this paper, we provide an updated overview of the common orofacial pain disorders following the ICOP, covering the classification, epidemiology, pathophysiology, clinical approaches, and treatment options. Additionally, we propose a pragmatic approach focusing on the attack duration to improve distinguishing orofacial disorders. Conclusion: The introduction of ICOP offers the opportunity to better coordinate and concentrate scientific efforts, which lays the foundation for the identification of the disease mechanism of facial pain disorders and the optimization of the currently still insufficient therapeutic strategies.

THE VOICE OF THE PATIENT IN OROFACIAL PAIN MANAGEMENT.

As pain cannot be measured objectively, the use of patient reported outcomes (PROs), and specifically dental PROs (dPROs), is essential for adequate assessment and management of the patient with orofacial pain. For orofacial pain conditions, some of the suitable PROs are specific to dentistry and hence can be labelled dPROs, whereas others are not. There is also a need to understand which outcomes and domains are most relevant to the patient with pain complaints within the context of the biopsychosocial model. Acute pain in the orofacial area is most often related to toothache, whereas the most common chronic orofacial pain are temporomandibular disorders. Other chronic pains in the orofacial area include neuropathic pain and unknown or idiopathic pain. PROs have been fundamental in the development of both screening procedures and diagnostic criteria in temporomandibular disorders. PROs are now often a prerequisite for the most common temporomandibular disorder pain diagnoses. Furthermore, PROs form the basis for decision-making with regard to treatment, prognostics, and referrals. Future areas of development include the standardized use of PROs in the screening and diagnostics of the less common orofacial pain conditions, together with development of core outcomes sets and standardized protocols for the use of PROs in evaluation of treatment including efficacy, compliance, adherence, and side-effects.

Outcomes of referrals from endodontic to orofacial pain specialists: A retrospective cohort study.

ObjectivesDiagnosis and treatment of non‐odontogenic pain is challenging for endodontists. The purpose of the study was to investigate the outcomes of referrals to orofacial pain specialists made for patients with suspected non‐odontogenic pain, after evaluation and/or treatment by an endodontist.Materials and MethodsA retrospective review of dental records was conducted for 60 patients referred from a postgraduate endodontic clinic to an orofacial pain clinic. Patient demographics, pain history, endodontic, and orofacial pain diagnoses were collected. Number of visits, length of treatment, and treatments prescribed were recorded. For analysis of outcomes, data pertinent to resolution/persistence of symptoms and patient compliance were analyzed.ResultsThirty‐five patients were included in the study. The most frequent pulpal and periapical diagnoses were previously treated (62%) and symptomatic apical periodontitis (72%), respectively. The most common orofacial pain diagnosis was temporomandibular disorder. The average time spent to diagnose and treat the pain was 17 months. Pain reduction varied and was documented for 51% of patients. Indications of non‐compliance with orofacial pain appointments and treatments were documented for 66% of patients.ConclusionsNon‐odontogenic pain diagnosis and treatment are challenging. Patients may have an increased predilection for developing persistent pain after endodontic treatment and/or have an undiagnosed, chronic orofacial pain condition as a true source of their chief complaint. It may be helpful for endodontists to set expectations of typical treatment times/plans when referring patients for evaluation and treatment of non‐odontogenic pain.

Prevalence of Sign and Symptoms of Temporomandibular Joint Disorders in Pakistani Population at Sheikhupura, Lahore: A Gender comparison

Background: Temporomandibular disorders have been considered as a common orofacial pain condition. The term temporomandibular pain dysfunction (TMPD) is used synonymously with myofacial pain dysfunction disorder/syndrome, temporomandibular disorder, craniomandibular disorder and many other terms. Objective: To evaluate the prevalence of signs and symptoms of temporo-mandibular joint disorder (TMD). Study Design: Descriptive cross-sectional study Place and Duration of Study: Department of Oral and Maxillofacial Surgery, Faryal Dental College, Sheikhupura , Lahore, Pakistan from 1st February 2019 to 31st May 2021. Methodology: One hundred adolescents aged 15 to 60 years were enrolled. A detailed history about the chief complaint was taken and clinical examination was done. Temporomandibular joint examination performed included Auscultation for temporomandibular joint sounds like clicking and crepitus and palpation of both TMJs and associated muscles for evaluation of pain. Results: The most common signs of temporomandibular joint disorders were temporomandibular joint pain 78%, temporomandibular joint clicking 53% and trismus 29%. The most prevalent predisposing factors of temporomandibular joint disorders were parafunctional habits 40%, unknown factors 23% and history of road traffic accident/history of difficult extractions 9%. Male to female ratio showed female predominance (P = 0.001). Conclusion: Signs and symptoms of temporomandibular joint disorders were prevalent in Pakistani population with a clear female predominance. Key words: Temporomandibular disorders, Temporomandibular joint, Orofacial pain, Bruxism, Headache, Pain

Temporomandibular disorder and serum levels of progesterone and estrogen: Systematic review

Temporomandibular Disorder (TMD) is a pathology of the stomatognathic system characterized by a set of clinical disorders that includes a temporomandibular joint, a masticatory musculature and associated structures. It is the most common orofacial pain condition of non-dental origin and which is increasing among adults in the age group between 18 and 45 years with a not well defined etiology, mainly not with regard to its higher prevalence in women than men. The present study aimed to evaluate the literature if there is a relationship between the levels of progesterone and estrogen with the clinical manifestations of TMD. The systematic search was carried out in the following electronic databases: PubMed, Web of Science, SciELO, and LILACS, Scopus, Embase and Google Scholar in addition to a complementary manual search of cross-references of original articles. There was no time restriction. The descriptors used were "TMD" or "TMJ" and "progesterone" and "estrogen". Initially, 132 articles were found, were 15 presented the eligibility criteria to be read in full. In the end, 4 studies were included in the review. The conclusion was that most studies relate the variations of progesterone and estrogen to the symptoms of the disease; however, there are differences between them. Thus, it is recommended to carry out studies that analyze this relationship, leading to hormonal fluctuations ranging from reproductive age to post-menopause.

Glia and Orofacial Pain: Progress and Future Directions.

Orofacial pain is a universal predicament, afflicting millions of individuals worldwide. Research on the molecular mechanisms of orofacial pain has predominately focused on the role of neurons underlying nociception. However, aside from neural mechanisms, non-neuronal cells, such as Schwann cells and satellite ganglion cells in the peripheral nervous system, and microglia and astrocytes in the central nervous system, are important players in both peripheral and central processing of pain in the orofacial region. This review highlights recent molecular and cellular findings of the glia involvement and glia–neuron interactions in four common orofacial pain conditions such as headache, dental pulp injury, temporomandibular joint dysfunction/inflammation, and head and neck cancer. We will discuss the remaining questions and future directions on glial involvement in these four orofacial pain conditions.

Comparative Evaluation of the Efficacy of Gabapentin and Gabapentin in Combination with Nortriptyline in the Management of Pain-Related Temporomandibular Disorders

Background: Temporomandibular disorders (TMDs) are considered the most common orofacial pain conditions of nonodontogenic origin. The current perspective regarding TMD is multidimensional. If the pain becomes chronic, it can have a great impact on the social and emotional behavior of the patient. Materials and Methods: A total of 40 patients between the age groups of 18 and 45 years were included in the study. These patients were divided into two groups comprising 20 patients each. Group I was prescribed gabapentin and was advised to take the medicine twice daily. Group II was prescribed gabapentin along with nortryptyline twice daily. Patients in each group were evaluated at the end of every week using a visual analog scale (VAS) score for pain, maximum interincisal mouth opening, and several muscle tenderness sites for 3 weeks, and a comparison was made. Results: The age range in group I was 19–45 years, whereas in group II it was 18–45 years with a P value of 0.711. Female predominance was observed in both groups as 65% of patients were females in group I and 60% were females in group II and P value obtained was 0.74. VAS score decreased more rapidly in group II than group I. The P value obtained was &lt;0.001 at the end of the third week. Comfortable moth opening shows a more effective increase in group II than group I. The P value (0.003) shows significance at the end of the third week. The mean number of muscle tenderness sites at the end of 3 weeks in group I and group II reduced to 1.15 and 0.40, respectively. Conclusion: The combination therapy of gabapentin with nortryptyline was found to be more effective than gabapentin alone.

Editorial: Disseminating Knowledge About Orofacial Pain— A Huge and Important Challenge

Editorial: Disseminating Knowledge About Orofacial Pain— A Huge and Important Challenge

Preliminary evidence for conserved transcriptional response to adversity in adults with temporomandibular disorder.

In the current study, we investigated whether individuals with TMD would exhibit differential activity of 3 specific transcription factors involved in inflammatory (nuclear factor-kappa B, NF-kB), antiviral (interferon-regulatory factors, IRF), and sympathetic (cAMP response element-binding protein, CREB) processes using a promoter-based bioinformatics analysis, which is characterized as the "Conserved Transcriptional Response to Adversity." Adults with TMD (n = 19) and without (n = 17) underwent a standardized clinical examination for TMD. A blood sample was collected for genome-wide transcriptional RNA profiling. Bioinformatic analyses tested for differential prevalence of proinflammatory and antiviral transcription factor activity in core promoter sequences from all genes showing >1.2-fold differential expression in TMD vs controls. Promoter-based bioinformatic analyses of genome-wide transcriptome profiles confirmed upregulation of genes bearing response elements for proinflammatory transcription factor (NF-kB, P = 0.002) and downregulation of genes with response elements for IRF (P = 0.037) in patients with TMD relative to controls. Results also indicated upregulated activity of CREB in patients with TMD (P = 0.08), consistent with increased activity of the sympathetic nervous system. These results provide initial support that the regulation of immune pathways is altered in individuals with TMD. A shift of transcriptional resources to a proinflammatory state may be driven by psychosocial stress and contributes to symptoms associated with TMD.

Awareness and Knowledge of General Dental Practitioners in Central India Towards Management of Patients with Temporomandibular Disorder: A Questionnaire-based Survey

Introduction: Temporomandibular Disorders (TMDs) accounts for common Orofacial Pain (OFP) arising from musculoskeletal origins, affecting almost 80% of the overall population. The multifactorial nature of the disease makes it difficult to diagnose and treat and is challenging to a considerable number of General Dental Practitioners (GDPs). They’re increasingly approached by patients for advice on TMD, but little is understood about how this disorder is addressed with in primary health care. Aim: To assess the awareness and knowledge regarding management of TMDs among GDPs in Central India. Materials and Methods: The cross-sectional study was conducted at Central India, Nagpur, Maharashtra, India from 20th June 2020 to 12th December 2020, including 200 general dental practitioners, who were registered under the Dental Council of India. A questionnaire consisting of 17 questions with reference to TMDs was designed and the questionnaire was circulated through a web designed program. The responses were collected, and data were analysed descriptively using Statistical Package for the Social Sciences (SPSS) statistics for windows version 24.0. Results: The mean age of the participants in the study was 24.80±1.63 years. Predominantly, participants were 164 females (82%). Among all the participants, about 181 (90.50%) of GDP’s were practicing Dentistry. The study findings suggest that the overall general practicing dentists encounter TMD cases and 162 (81%) of GDP’s treat patient at their clinic. A 76% of GDPs acknowledged the causative factor for TMD to be multifactorial and physical examination (88.50%) as the diagnostic tool. Most of the general practitioners around 126 (63%) preferred referring the patient to the specialist, maxillofacial surgeon. Among the practitioners who were confident in treating TMD, occlusal splint was the treatment of choice for 198 (96%) of the GDPs. Conclusion: Many GDPs lack standard protocol knowledge, felt insecure in TMD diagnosis, therapy decisions and treatment. There is a requirement for better quality evidence on which TMD diagnosis and treatment, including the event of a valid, reproducible patient-centered outcome measure to enable dental practitioners to feel confident in managing TMD. It is essential to train GDPs to identify individuals with TMDs through professional courses and training. It would be highly beneficial to educate the undergraduates regarding the diagnosis of TMDs in their curriculum.

Accuracy of online symptom checkers for diagnosis of orofacial pain and oral medicine disease.

The aim of this study was to compare and contrast the diagnostic accuracy of multiple online symptom checkers when used for the diagnosis of orofacial pain and oral medicine related disease vignettes. The comparison condition used in this study was the diagnostic accuracy achieved by advanced specialty residents on these same vignettes using a virtual patient system. 27 individual disease vignettes were utilized. These vignettes had a variety of orofacial pain and oral medicine diseases. Post graduate orofacial pain and oral medicine residents at our University of Southern California interacted with their randomly assigned virtual patients were analyzed [n=574]. Virtual patient accuracy was based on whether the user selected the primary diagnosis as one of their top four choices after interviewing. Eleven English-language symptom checkers accuracy was based on whether the vignettes produced the primary diagnosis as one of their top four choices. Using these data, symptom checker and virtual patient accuracy rates were calculated. The primary diagnosis on virtual patient encounters was found within the top four choices a mean of 67.2% of the time. The primary diagnosis for the same vignettes entered into the 11 symptom checkers was found within the top four choices a mean of 5.9% of the time. The accuracy of currently available symptom checkers that patient might use for self-diagnosis of common orofacial pain and oral medicine diseases was low, this result suggest that the improved diagnostic algorithms are needed.

The impact of oro-facial pain conditions on oral health-related quality of life: A systematic review.

Pain in the oro-facial region is one of the most common reasons for patients to seek dental treatment. Oral health-related quality of life (OHRQoL) can be affected not only by pain, but also by other oral disorders. Four main dimensions, Oral Function, Orofacial Pain, Orofacial Appearance and Psychosocial Impact, have been suggested to cover different areas of OHRQoL. The aim of this systematic review was to map the impact of oro-facial pain conditions on the Orofacial Pain dimension of OHRQoL (PROSPERO registration: CRD42017064033). Studies were included if they reported Oral Health Impact Profile (OHIP) mean or median domain scores for patients with odontogenic pain, oral mucosal pain/burning mouth syndrome (BMS), third molar extractions or temporomandibular disorders (TMD). A search in PubMed (MEDLINE), EMBASE, Cochrane, CINAHL and PsycINFO on 8 June 2017, updated 14 January 2019, combined with a hand search identified 2104 articles. After screening of abstracts, 1607 articles were reviewed in full text and 36 articles were included that reported OHIP data for 44 patient populations including 5849 patients. Typical Orofacial Pain impact for all four conditions (odontogenic pain, oral mucosal pain/BMS, pain after third molar extractions and TMD) was between 2 and 3 on a 0-8 converted OHIP scale with the highest reported impact for pain after 3rd molar extractions. This review provides standardised information about OHRQoL impact from four oro-facial pain conditions as a model for the Orofacial Pain dimension. The results show moderate impact for the pain dimension of OHRQoL in patients with common oro-facial pain conditions.

Temporomandibular joint disorders

The temporomandibular joint (TMJ) is prone to a number of disease states involving any one of its anatomical components. The current favoured term for problems associated with the TMJ is ‘temporomandibular disorder’ (TMD). TMD is one of the most common orofacial pain conditions. Patients will present to GPs and general dental practitioners as well as directly to accident and emergency, typically for referral to Oral and maxillofacial surgery, due to either significant acute pain or chronic pain that can no longer be tolerated. Common features of TMD include pain in the face and preauricular area, restricted jaw movement, and noise from the TMJs during jaw movements. TMD can coincide with poor general health, psychological co-morbidities such as depression and often affects quality of life.

Pharmacological and Surgical Treatment for Trigeminal Neuralgia a Review of the Literature

Trigeminal neuralgia is the most common orofacial pain, with incidence levels that increase every year. Characterized by paroxysmal attacks of pain, brief, lancinating, stabbing, is considered one of the most painful conditions affecting patients. Drug therapy has been the gold standard for the management and control of this neuropathy, on the contrary, recent studies find wide drug resistance with history of neuralgia for many years, causing recurrence of the picture. That is why there is a need to establish a proper surgical planning, among which stands vascular decompression and percutaneous micro harmful methods such as retrogasserianas rhizotomies, chemical methods, such as injection of alcohol or glycerol in the oval hole, mental foramen, as an alternative to medical-pharmacological treatment, however, not all procedures reviewed in the literature indicate a continued success rate and further, the various adverse effects involving the implementation of each treatment should be considered.

Temporomandibular disorders: Old ideas and new concepts.

Background Temporomandibular disorders (TMD) is an umbrella term for pain and dysfunction involving the masticatory muscles and the temporomandibular joints (TMJs). TMD is the most common orofacial pain condition. Its prominent features include regional pain in the face and preauricular area, limitations in jaw movement, and noise from the TMJs during jaw movements. TMD affects up to 15% of adults and 7% of adolescents. Chronic pain is the overwhelming reason that patients with TMD seek treatment. TMD can associate with impaired general health, depression, and other psychological disabilities, and may affect the quality of life of the patient. Assessment Evaluations indicate that the recently published Diagnostic Criteria for TMD (DC/TMD) are reliable and valid. These criteria cover the most common types of TMD, which include pain-related disorders (e.g., myalgia, headache attributable to TMD, and arthralgia) as well as disorders associated with the TMJ (primarily disc displacements and degenerative disease). As peripheral mechanisms most likely play a role in the onset of TMD, a detailed muscle examination is recommended. The persistence of pain involves more central factors, such as sensitization of the supraspinal neurons and second-order neurons at the level of the spinal dorsal horn/trigeminal nucleus, imbalanced antinociceptive activity, and strong genetic predisposition, which also is included in DC/TMD. Conclusion The etiology is complex and still not clearly understood, but several biological and psychosocial risk factors for TMD have been identified. Several studies indicate that patients with TMD improve with a combination of noninvasive therapies, including behavior therapy, pharmacotherapy, physical therapy, and occlusal appliances. More stringently designed studies, however, are needed to assess treatment efficacy and how to tailor treatment to the individual patient.