Journal of Oral & Facial Pain and Headache最新文献

Aims: To investigate the sensitivity and specificity of the TMD pain screener in a headache population.

Methods: A cross-sectional study was conducted at the Danish Headache Center (DHC). Patients were included if they had primary or secondary headache, trigeminal neuralgia, or facial pain. The pain screener was compared to the outcome of a full Diagnostic Criteria for TMD (DC/TMD) examination.

Results: A total of 62 headache patients were included (77% women). The sensitivity of the pain screener short version (three questions) was 85% (95% CI: 70% to 94%), and the specificity was 64% (95% CI: 41% to 83%). In the full version (six questions), the sensitivity was 83% (95% CI: 67% to 93%), and the specificity was 82% (95% CI: 60% to 95%).

Conclusion: The TMD pain screener seems to be a valid tool to accurately screen for the presence of TMD to provide the most optimal treatment for headache patients. These findings should however be confirmed in a larger sample with migraine, tension-type headache, and trigeminal neuralgia.

Aims: To investigate the role of exercise-induced hypoalgesia (EIH) in the development of neuropathic pain (NP) following infraorbital nerve (ION) injury and to explore possible underlying mechanisms defining the differences between rats with high and low EIH.

Methods: EIH was evaluated by measuring the percentage of withdrawal responses to a series of 30 mechanical stimuli applied to the hind paw before and after 180 seconds of exercise on a rotating rod. The rats were assigned to low- and high-EIH groups based on reduction in the percent of withdrawal responses following exercise. NP was induced in high- and low-EIH rats via ION constriction injury. Rats were tested with graded nylon monofilaments to establish the withdrawal threshold. Increasingly stiff monofilaments were applied to the ION territory until there was a clear withdrawal by the rat. This was repeated a total of three times. A decreased withdrawal threshold indicates allodynia. Testing was performed at baseline and at 3, 10, and 17 days following the injury. On day 17 postinjury, IONs were harvested for the assessment of interleukin (IL)-6, IL-1β, and IL-10 levels. Samples from high-EIH and low-EIH surgically naïve rats served as control for the cytokines study. In this second part of the study, the effects of cannabinoid 1 (CB1) and cannabinoid 2 (CB2) antagonists and naltrexone on EIH profiles and on the withdrawal thresholds to mechanical stimulation were measured. EIH and withdrawal thresholds in high- and low-EIH rats were measured before and after administration of antagonists.

Results: Low-EIH rats developed significantly more pronounced allodynia in the ION territory following injury compared to high-EIH rats. At 17 days postinjury, ION IL-1β levels were higher in low-EIH rats, and IL-10 levels were higher in high-EIH rats. CB1 antagonist blocked the analgesic effect induced by exercise in high- but not in low-EIH rats. The CB2 antagonist had no significant effect on high- or low-EIH rats. Naltrexone blocked the effects of EIH in both high- and low-EIH rats. Exercise induced a significant analgesic effect in high-EIH but not in low-EIH rats. CB1 or CB2 antagonist administration had no effect on pre-exercise responses to mechanical stimulation, while naltrexone administration resulted in significant allodynia in both low- and high-EIH rats.

Conclusion: This study demonstrated substantial differences between rats with high and low EIH. The results suggest that following ION injury, high-EIH rats may have a more prominent or activated endocannabinoids system and that their inflammatory response is moderated, with higher levels of IL-10 and lower levels of IL-1β.

Aims: To systematically review the literature to assess whether genetic polymorphisms affect orofacial pain sensitivity in healthy individuals and in patients with chronic orofacial pain disorders.

Methods: Electronic searches were conducted to identify observational studies and clinical trials investigating the association between genetic polymorphisms and orofacial pain sensitivity in healthy individuals and/or patients with chronic orofacial pain disorders. Searches were carried out in PubMed, Embase, and Scopus databases using Medical Subject Headings and free terms.

Results: Seven studies fulfilled the eligibility criteria: four analyzed healthy subjects, two included chronic orofacial pain patients, and one included samples of healthy subjects and patients with neuropathic pain. The results showed that genes associated with mechanical and thermal pain sensitivity were mostly related to opioid, catecholaminergic, inflammatory, and dopaminergic pathways.

Conclusion: Genetic polymorphisms related to opioid, catecholaminergic, inflammatory, and dopaminergic pathways were associated with sensitivity to thermal and pressure stimuli in the orofacial region. Therefore, genetic factors should be taken into account for an accurate interpretation of orofacial pain sensitivity. These results will allow for a better understanding of the etiopathogenesis of chronic pain affecting the orofacial region, and consequently for finding new therapeutic targets.

Aims: To evaluate the association between sleep bruxism (SB) and quality of life (QoL) in the general population.

Methods: A systematic review was conducted, and studies were included with no restrictions regarding age, gender, or language. SB and general health-related QoL and/or oral health-related QoL (OHRQoL) measures in the included studies needed to be based on validated tools. The databases searched were Google Scholar, LILACS, OpenGrey, ProQuest, PubMed, Science Direct, Scopus, and Web of Science. Quality of evidence was evaluated using the Joanna Briggs Institute critical appraisal checklists and GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria.

Results: Fourteen studies met the inclusion criteria. Ten studies were published in English, and four in Portuguese. All studies evaluating the association of SB with health-related QoL showed no statistical significance when overall scores were considered. The overall quality of evidence was considered very low due to high heterogeneity among the studies. SB seemed not to be associated with health-related QoL, but did have a negative impact on some characteristics of OHRQoL.

Conclusion: There is insufficient scientific evidence to support or disprove the association between SB and QoL/OHRQoL in the general population.

Aims: To investigate inflammatory mediator levels in TMJ synovial fluid (SF) and blood and to investigate clinical TMJ symptoms in relation to general and TMJ symptom duration in patients with rheumatoid arthritis (RA).

Methods: Examination of 80 TMJs (68 patients; median age 55 years; 85% women) included the following variables: TMJ pain at rest, maximum mouth opening, and palpation; jaw movement capacity; number of painful movements; crepitus; and degree of anterior open bite. Levels of tumor necrosis factor (TNF), TNF soluble receptor II, interleukin 1β, IL-1 receptor antagonist, IL-1 soluble receptor II, and serotonin in TMJ SF and blood; systemic disease activity; and duration of general and TMJ symptoms were assessed. General symptom duration ≤ 2 years was considered early RA.

Results: TMJ symptoms predominantly developed within 5 years following general symptom onset. Logistic regression analysis showed that number of involved joints, general pain, maximum mouth opening, anterior open bite, and TNF plasma levels combined explained 46% of the distinction between early and established RA. Furthermore, TMJ pain at rest and maximum mouth opening, contralateral laterotrusion, painful movements, crepitus, and SF TNF levels combined explained 35% of the distinction. In these analyses, higher general pain and maximum mouth opening, TMJ pain on maximum mouth opening, and crepitus were associated with early RA.

Conclusion: This study indicates that TMJ pain and crepitus in RA usually occur within 2 years following general symptom onset. Pain-related dysfunction and structural changes develop with time. TNF in plasma and TMJ SF are associated with this development. This makes early (clinical) recognition of pain and inflammation important, enabling early treatment to minimize later irreversible damage.

Aims: To assess the prevalence of catastrophizing in patients with temporomandibular disorders (TMD) and the possible associations between catastrophizing and treatment outcome.

Methods: This review was registered in the Prospero database (CRD42018114233). Electronic searches were performed in PubMed, Scopus, and PsycINFO from the inception of each database up to October 26, 2018, and were combined with a hand search. Articles focusing on levels of catastrophizing and how catastrophizing affects pain levels and treatment outcomes for patients diagnosed with TMD were included, as well as studies reporting how treatment outcomes were affected by cognitive behavioral treatment as an addition to standard treatment for TMD. Reviews and case reports were excluded. Risk of bias was assessed with the Newcastle-Ottawa scale.

Results: The literature search identified 266 articles. After screening of abstracts, the full texts of 59 articles were assessed. Of these, 37 articles, including 4,789 patients with TMD and 6,617 controls, met the inclusion criteria. Higher levels of pain catastrophizing were reported in patients with TMD, with a large effect size (Hedges' g = 0.86) compared to pain-free controls. Furthermore, associations of higher levels of catastrophizing with higher symptom severity and with poorer treatment outcome were reported together with indications of positive effects from cognitive behavioral therapy.

Conclusion: The results suggest an association between catastrophizing and TMD that may affect not only symptom severity but also treatment outcome. Assessing levels of pain catastrophizing might therefore be valuable in the assessment and management of patients with TMD.

Aims: To compare two pain models of myalgic TMD, delayed-onset muscle soreness (DOMS) and injections of nerve growth factor (NGF), in terms of pain-related and motor function outcomes, as well as activity-related temporal summation.

Methods: Fifty age- and gender-matched healthy participants were recruited and randomized into one of three groups: to a repeated eccentric contraction task to cause DOMS (n = 20), to receive NGF injections into the masseter muscle (n = 20), or to a control group (n = 10). Mechanical sensitivity of masticatory muscles, chewing parameters, jaw function limitation, maximum bite force, and activity-related temporal summation were assessed at baseline and at days 1, 2, and 7 following the intervention.

Results: Compared to baseline, both model groups showed increased mechanical sensitivity, jaw function limitation, pain on chewing, and decreased chewing efficiency, lasting longer in the NGF group than in the DOMS group (P < .05). Furthermore, also compared to baseline, the NGF group showed increased pain on maximum bite and decreased pain-free maximum opening (P < .05). No increases in activity-related temporal summation were shown for any of the model groups when compared to baseline or the control group (P > .05).

Conclusion: Both models produced similar pain-related outcomes, with the NGF model having a longer effect. Furthermore, the NGF model showed a more substantial effect on motor function, which was not seen for the DOMS model. Finally, neither of the models were able to provoke activity-related temporal summation of pain.

Aims: To investigate how estrogen level, dietary loading, and aging affect cartilage structure and the expression of major collagens (types I, II, and X) in rat mandibular condylar cartilage (MCC).

Methods: A total of 96 outbred Sprague Dawley female rats were randomly divided into two groups by ovariectomy (OVX) at 7 weeks old. One week later, the rats in each group were further divided into three subgroups on the basis of food hardness: hard food (diet board), normal food (pellet), and soft food (powder). The rats were sacrificed at the age of 5 or 14 months. The thickness of the fibrous, proliferative, and chondroblastic layers of the mandibular condylar cartilage were measured after toluidine blue staining. Immunohistochemical analysis was performed to evaluate the expression levels of types I, II, and X collagen. A linear regression model was used to investigate the main factors affecting changes in thickness and collagen expression.

Results: The expression levels of types II and X collagen were decreased by ovarian estrogen deficiency and increased by dietary loading. Increased dietary loading was the main factor affecting an increase in thickness of the cartilage layers, while aging was the main factor affecting a decrease in thickness of the fibrous layer. A significant age-related increase was found in the expression of type I collagen. There was some degree of interaction between aging and dietary loading that affected the thickness of the chondroblastic layer and the expression of type X collagen.

Conclusion: The physiologic level of estrogen plays a role in MCC development by promoting the expression of types II and X collagen. Dietary loading is essential to increase the expression of types II and X collagen, as well as the thickness of cellular layers, to maintain the integrity of the MCC. Aging seems to reduce the ability of the MCC to withstand occlusal loading.