Perspectives on next steps in classification of oro-facial pain - Part 3: biomarkers of chronic oro-facial pain - from research to clinic

The purpose of this study was to review the current status of biomarkers used in oro-facial pain conditions. Specifically, we critically appraise their relative strengths and weaknesses for assessing mechanisms associated with the oro-facial pain conditions and interpret that information in the light of their current value for use in diagnosis. In the third section, we explore biomarkers through the perspective of ontological realism. We discuss ontological problems of biomarkers as currently widely conceptualised and implemented. This leads to recommendations for research practice aimed to a better understanding of the potential contribution that biomarkers might make to oro-facial pain diagnosis and thereby fulfil our goal for an expanded multidimensional framework for oro-facial pain conditions that would include a third axis

Dores orofaciais: mecanismos básicos e implicações para um tratamento efetivo

Orofacial Pain is the field of dentistry devoted to the diagnosis and management of chronic, complex, facial pain and oromotor disorders. This specialty in dentistry has developed over a number of years out of the need for better understanding of a group of patients who somehow were not clearly suffering from dental pain disorders, but still did not seem to have a clearly defined medical problem. After a long period of treating patients based on the mechanicist aspect of the disease, our profession has realized the importance of basic knowledge and differencial diagnosis in order to proper manage these patients. This modification in the approach has caused severe changes in education as well as in clinical activities. Historically considered as a problem of occlusion, Orofacial Pain, including Temporomandibular Disorders (TMD) has recently reached the status of "Specialty" in Brazil. Therefore, this paper aims to discuss the main differences between musculoskeletal and neuropathic pain and the importance of basic knowledge to perform successful management.Dor Orofacial é um campo da odontologia dedicado ao diagnóstico e tratamento de dores orofaciais crônicas e complexas, além d e desordens motoras. Essa especialidade odontológica tem se desenvolvido por vários anos com o objetivo de prover um melhor entendimento de um grupo de pacientes que, de alguma forma, não tinham dores de origem dentária e nem condições óbvias médicas que explicassem suas dores na face. Depois de um longo período propondo tratamentos baseados apenas no aspecto mecanicista da doença, nossa profissão percebeu a importância de entender mecanismos básicos de diagnóstico diferencial para melhor controlar esses casos. Essa mudança de mentalidade tem levado a modificações na educação em odontologia, assim como nos procedimentos clínicos executados. Historicamente considerada como um "problema de oclusão", as dores orofaciais obtiveram recentemente o reconhecimento como especialidade em nosso país. Baseado nisso, o objetivo desse artigo é discutir diferenças básicas entre os tipos mais comuns de dor orofacial, assim como ressaltar a importância do conhecimento de mecanismos de condução de dor para a formulação de um plano de tratamento efetivo

Effect of Clear Aligner Therapy on Masticatory Muscle Tenderness and Orthodontic Pain

Introduction: Patients undergoing orthodontic clear aligner therapy (CAT) may experience discomfort in their teeth and jaws, and often present with visible wear on their aligners. This multi-site prospective clinical study aimed to analyze tooth pain and masticatory muscle tenderness in patients subjected to CAT with Invisalign©. Methods: Twenty-seven healthy adults undergoing treatment with Invisalign© were recruited from three university-based orthodontic clinics. Tooth pain and muscle tenderness were reported on visual analog scales in pain diaries prior to, and after starting CAT. Pressure pain thresholds (PPT) measured using pressure algometers were used to assess somatosensory changes in trigeminal and extra-trigeminal locations. Results: The aligners resulted in tooth pain, which was greater with the initial passive aligner than the subsequent active aligners (all p0.05). Conclusion: In the short-term, CAT results in mild tooth pain and jaw muscle tenderness of likely limited clinical significance, and does not result in significant somatosensory changes

Signal acquisition and analysis of ambulatory electromyographic recordings for the assessment of sleep bruxism : A scoping review

Background Ambulatory electromyographic (EMG) devices are increasingly being used in sleep bruxism studies. EMG signal acquisition, analysis and scoring methods vary between studies. This may impact comparability of studies and the assessment of sleep bruxism in patients. Objectives (a) To provide an overview of EMG signal acquisition and analysis methods of recordings from limited-channel ambulatory EMG devices for the assessment of sleep bruxism; and (b) to provide an overview of outcome measures used in sleep bruxism literature utilising such devices. Method A scoping review of the literature was performed. Online databases PubMed and Semantics Scholar were searched for studies published in English until 7 October 2020. Data on five categories were extracted: recording hardware, recording logistics, signal acquisition, signal analysis and sleep bruxism outcomes. Results Seventy-eight studies were included, published between 1977 and 2020. Recording hardware was generally well described. Reports of participant instructions in device handling and of dealing with failed recordings were often lacking. Basic elements of signal acquisition, for example amplifications factors, impedance and bandpass settings, and signal analysis, for example rectification, signal processing and additional filtering, were underreported. Extensive variability was found for thresholds used to characterise sleep bruxism events. Sleep bruxism outcomes varied, but typically represented frequency, duration and/or intensity of masticatory muscle activity (MMA). Conclusion Adequate and standardised reporting of recording procedures is highly recommended. In future studies utilising ambulatory EMG devices, the focus may need to shift from the concept of scoring sleep bruxism events to that of scoring the whole spectrum of MMA.Peer reviewe

The Role 18F-FDG and 18F-NaF PET/CT in Assessment of Temporomandibular Joint Metabolic Activity in Rheumatoid Arthritis

Objective: The aim of this study was to evaluate the efficacy of 18F-fluorodeoxyglucose (FDG) and 18F-sodium fluoride (NaF)PET/CT for assessing the status of the temporomandibular joint (TMJ) of rheumatoid arthritis (RA) patients compared with healthy (non-RA) individuals. Method: Eighteen patients diagnosed with RA (mean age 55±12.1years: 4 females and 14 males) were included in the test group. Eighteen age-, sex- and race-matched healthy control subjects were selected from the CAMONA clinical trial. PET/CT images were acquired 180-minute post-intravenous administration of FDG and NaF (2.2 MBq/kg). For FDG analysis, regions of interest (ROIs) were manually assigned per anatomical boundaries using a closed polygon tool. The first ROI of the mask was assigned on the trans-axial CT slice with the first evidence of the glenoid fossa down to two to three slices inferiorly. The ROI followed the anatomy of the TMJ. For NaF, a three-dimensional ball tool of 1.5 cm was used to assign ROIs with the head of the mandibular condyle located at the center including the osseous compartment of the joint extending inferiorly to the neck of the condyle. Averaged SUVmean was used to semi-quantify FDG and NaF uptake in each joint. Then average SUVmean of the right and the left TMJ was determined. For normalization, a Target to Background Ratio (TBR) was used. For statistical analysis, the student’s t-test and regression analysis were used. The severity of RA was assessed by determining the Disease Activity Score of serum C reactive protein (DAS-28 CRP) and erythrocyte sedimentation rate (DAS-28 ESR) for each subject. Results: FDG TBRmean for the test group was 1.21±0.33 compared to 0.91±0.2 in controls, (p=0.003.) No correlation was found between FDG uptake and DAS28-CRP or DAS28-ESR. The NaF average SUVmean was significantly higher in RA patients than healthy control subjects (2.4±0.8 versus 1.9±0.4, p=0.02). Similarly, the TMJ TBRmean was also higher in RA patients relative to healthy controls (4.2±2.1 versus 2.7±0.9, p=0.01) A significant positive correlation was found between TBRmean and DAS28-CRP (r=0.49, p=0.03), while there was positive trend in the correlation between TBRmean with DAS28-ESR that was not statistically significance (r=0.37, p=0.12). Conclusion: RA patients appear to have significantly higher metabolic activity in the TMJ than age-, sex- and race-matched healthy control subjects. Our results illustrate the potential value of using FDG and NaF-PET/CT for evaluation of TMJ disorders and suggest that this modality may useful for monitoring the effects of treatment regimens

Physical Therapy and Internal Derangement of the Temporomandibular Joint

In orthopedic literature, internal derangement is considered to be one of the main predisposing factors in the development of temporomandibular joint dysfunction and subsequent arthrosis. Internal derangement can be defined as the abnormal relationship of the articular disc to the condyle and consists of a multitude of disorders. Physical therapy is well-recognized as an effective, conservative method of treatment for temporomandibular disorders. Early treatment to correct symptomatic internal derangement decreases the possibility of disc deformation and further joint degeneration. However, much of the physical therapy literature consists of uncontrolled case studies and focal clinical technique articles. For this reason, there is a need for well-controlled outcome studies. The proposed review of literature will clarify current knowledge concerning internal derangement and define the role of physical therapy in its management. The review will illustrate the etiology, clinical manifestation, and progression of derangement. The current views regarding medical management will be discussed

Signal acquisition and analysis of ambulatory electromyographic recordings for the assessment of sleep bruxism: A scoping review

Background: Ambulatory electromyographic (EMG) devices are increasingly being used in sleep bruxism studies. EMG signal acquisition, analysis and scoring methods vary between studies. This may impact comparability of studies and the assessment of sleep bruxism in patients. Objectives: (a) To provide an overview of EMG signal acquisition and analysis methods of recordings from limited-channel ambulatory EMG devices for the assessment of sleep bruxism; and (b) to provide an overview of outcome measures used in sleep bruxism literature utilising such devices. Method: A scoping review of the literature was performed. Online databases PubMed and Semantics Scholar were searched for studies published in English until 7 October 2020. Data on five categories were extracted: recording hardware, recording logistics, signal acquisition, signal analysis and sleep bruxism outcomes. Results: Seventy-eight studies were included, published between 1977 and 2020. Recording hardware was generally well described. Reports of participant instructions in device handling and of dealing with failed recordings were often lacking. Basic elements of signal acquisition, for example amplifications factors, impedance and bandpass settings, and signal analysis, for example rectification, signal processing and additional filtering, were underreported. Extensive variability was found for thresholds used to characterise sleep bruxism events. Sleep bruxism outcomes varied, but typically represented frequency, duration and/or intensity of masticatory muscle activity (MMA). Conclusion: Adequate and standardised reporting of recording procedures is highly recommended. In future studies utilising ambulatory EMG devices, the focus may need to shift from the concept of scoring sleep bruxism events to that of scoring the whole spectrum of MMA