Influence of psychometric and sleep quality features on painful mechanical sensitivity and pain modulation in patients with temporomandibular disorders.

Investigating the collective impact of psychometric properties and sleep quality on pain sensitivity in temporomandibular disorder (TMD) patients could improve clinical management strategies. OBJECTIVE: Assessing whether combined psychometric properties and sleep quality impact painful mechanical sensitivity and pain modulation in TMD patients. MATERIALS AND METHODS: A cross-sectional study using secondary data analysis of 77 TMD patients and 101 controls. All participants completed questionnaires characterizing their psychometric profile (anxiety, depression, stress and catastrophizing) and sleep quality, alongside psychophysical tests for painful mechanical sensory (mechanical pain threshold (MPT), pressure pain threshold (PPT), and wind-up ratio (WUR)) and conditioned pain modulation (CPM). Participants were grouped into "High distress" or "Low distress" categories based on psychometric properties and sleep quality using hierarchical cluster and k-means analyses. Multiple linear regression evaluated the influence of TMD, age, and the distress cluster on MPT, WUR, PPT, and CPM in masseter and thenar muscles. Differences were statistically significant when p < 0.05. RESULTS: The presence of TMD was the strongest predictor of mechanical painful sensitivity in the trigeminal region (MPT[F(3,174) = 51.902;p < .001;R2 = .463]; TMD presence (ß = -.682) / PPT[F(3,174) = 15.573;p < .001;R2 = .198] TMD presence (ß = -.452), and extra-trigeminal (MPT[F(3,174) = 35.897;p < .001;R2 = .382] TMD (ß = -.647) / CPM [F(3,174) = 4.106;p < .05;R2 = .050] TMD presence (ß = .197). Furthermore, neither the high distress group nor the low distress group were able to significantly influence the variation of the values of any of the psychophysical variables evaluated (p > .05). CONCLUSIONS: There is not a significant influence of impairment clusters based on psychological variables and sleep quality on painful mechanical sensitivity and pain modulation, regardless of the presence of TMD. CLINICAL RELEVANCE: This outcome suggests that psychosocial factors and sleep quality may not play a decisive role in the sensory-discriminative aspect of pain, particularly concerning painful TMD.

Prediction of duloxetine efficacy in addition to self-management in painful temporomandibular disorders: A randomised, placebo-controlled clinical trial.

BACKGROUND: Conditioned pain modulation (CPM) is a potential predictor of treatment response that has not been studied in temporomandibular disorders (TMD). OBJECTIVES: We conducted a randomised, double-blind, placebo-controlled trial (RCT) of duloxetine in addition to self-management (SM) strategies to investigate its efficacy to reduce pain intensity in painful TMD patients. Moreover, we investigated whether baseline CPM would predict the duloxetine efficacy to reduce TMD pain intensity. METHODS: Eighty participants were randomised to duloxetine 60 mg or placebo for 12 weeks. The primary outcomes were the change in the pain intensity from baseline to week-12 and CPM-sequential paradigm at baseline. Safety, physical and emotional functioning outcomes were also evaluated. RESULTS: Of 80 participants randomised, 78 were included in intention-to-treat analysis. Pain intensity decreased for SM-duloxetine and SM-placebo but did not differ between groups (p = .82). A more efficient CPM was associated with a greater pain intensity reduction regardless of the treatment group (p = .035). Physical and emotional functioning did not differ between groups, but adverse events (p = .014), sleep impairment (p = .003) and catastrophizing symptoms (p = .001) were more prevalent in SM-duloxetine group. CONCLUSION: This study failed to provide evidence of a beneficial effect of adding duloxetine to SM strategies for treatment of painful TMD. Nonetheless, this RCT has shown the feasibility of applying pain modulation assessment to predict short-term treatment response in painful TMD patients, which confirms previous finds that CPM evaluation may serve a step forward in individualising pain treatment.

Referred pain is associated with greater odontogenic spontaneous pain and a heightened pain sensitivity in patients with symptomatic irreversible pulpitis.

BACKGROUND: Symptomatic irreversible pulpitis often results in heightened reactions to thermal stimuli such as pain evoked by a cold stimulus, and spontaneous odontogenic pain (unprovoked pain). OBJECTIVE: This study primarily compared the clinical manifestations of odontogenic spontaneous pain and pain provoked by cold stimulus specifically focusing on their sensory discriminative characteristics (intensity, duration and quality) between symptomatic irreversible pulpitis patients with and without referred pain. METHODS: Twenty-three patients with symptomatic irreversible pulpitis with referred pain and 12 patients without referred pain were included in this cross-sectional study. The following outcomes were assessed: odontogenic spontaneous pain and its descriptors; pain evoked by cold stimulus and qualitative sensory testing before and after local anaesthesia; referred pain location; use of analgesic medication; complementary anaesthesia efficacy. T-test, chi-squared and McNemar tests were applied to the data (p < .50). RESULTS: Patients with referred pain presented a greater odontogenic pain intensity (p < .05) when considered the average of the last 24 h. These patients also showed higher pain rating and pain descriptors (p < .05). Intensity and duration of the pain evoked by cold stimulus in the non-affected contralateral tooth at baseline were higher for patients with referred pain (p < .05). CONCLUSION: Symptomatic irreversible pulpitis patients with referred pain present greater odontogenic spontaneous pain and a heightened pain sensitivity. Therefore, patients with referred pain seem more complex from a pain severity perspective, supporting the clinical utility of discriminating symptomatic irreversible pulpitis with and without referred pain.

Nutrition and chronic musculoskeletal pain: A narrative review and directions for temporomandibular disorder research and management.

BACKGROUND: Recent evidence suggests neuro-immune mechanisms may link dietary patterns to chronic painful conditions (CPC). In the research field of oro-facial pain (OFP), studies focuses primarily on dietary mechanical limitations due to pain and dysfunction. OBJECTIVE: This narrative review aimed to overview the role of nutrition on CPC, with emphasis on temporomandibular disorder (TMD), enlightening OFP researcher on dietary assessment possibilities and providing directions for studies in the field of OFP and nutrition. METHODS: A PubMed database search was performed using the MeSH and non-MeSH descriptors: "temporomandibular joint disorder"; "orofacial pain"; "musculoskeletal pain"; "chronic pain disorders"; "nutrition"; "diet"; "dietary therapy"; "dietary intake" and "inflammation". No time restrictions were applied. Literature reviews, systematic reviews, meta-analyses and clinical and pre-clinical trials were included. RESULTS: Exogenous oxidants from unhealthy dietary patterns may contribute to peripheral and central pro-inflammatory immune signalling leading to peripheral and central sensitization. Furthermore, diets rich in bioactive compounds are suggested to contribute to pain management of CPC. High dietary intake of ultra-processed foods impacts the quality of the diet and shows adverse health outcomes. In this context, the role of nutrition on TMD remains overlooked. CONCLUSION: Considering diet may influence CPC, allied with the scarcity of studies evaluating the role of nutrition on TMD, well-designed clinical trials based on dietary assessments and measurements capable of evaluating food quality, UPF consumption and nutrient adequacy-added to serum nutrient levels evaluation-are suggested.

Influence of genetic polymorphisms on mechanical pain sensitivity and endogenous pain modulation of trigeminal and spinal areas.

BACKGROUND: Previous evidence indicates significant association between genetic polymorphisms and phenotypes related to pain sensitivity in patients with temporomandibular disorders (TMD). Despite the important advances in cataloguing diverse factors such as sleep disorders, anxiety and depression, the interrelated mechanisms of painful TMD aetiopathogenesis still need investigation. OBJECTIVES: This case-control study aimed to evaluate the influence of genetic polymorphisms (rs6296, rs6295, rs1799971, rs4680, rs4633, rs4818) and psychosocial factors on the mechanical pain sensitivity and endogenous pain modulation in women with painful TMD and asymptomatic controls. METHODS: We evaluated six independent variables: anxiety levels, depression, stress, sleep quality, pain catastrophising and genetic polymorphisms, and four dependent variables: mechanical pain threshold (MPT), pressure pain threshold (PPT), wind-up ratio (WUR) and conditioned pain modulation (CPM) collected at masseter (trigeminal) and hand (spinal) areas in a sample of 95 painful TMD patients and 85 controls. A regression model was used to test the possible effect of the independent variables on dependent variables. RESULTS: The regression model was significant for MPT (F11,168  = 9.772; R2  = .390). Painful TMD diagnoses and sleep quality were associated with trigeminal MPT (B coefficient = -.499; and B coefficient = -.211, respectively). WUR was associated with rs6295 and rs6746030, respectively, for the spinal and the trigeminal area. CONCLUSION: Genetic polymorphisms had a slight contribution to endogenous pain modulation as indicated by the significant association with WUR but did not contribute to mechanical pain sensitivity. On the other hand, the presence of painful TMD and the sleep quality contributed significantly to mechanical pain sensitivity.

Diagnostic criteria for temporomandibular disorders-INfORM recommendations: Comprehensive and short-form adaptations for children.

BACKGROUND: The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) are used worldwide in adults. Until now, no adaptation for use in children has been proposed. OBJECTIVE: The aim of this study was to present comprehensive and short-form adaptations of Axis I and Axis II of the DC/TMD for adults that are appropriate for use with children in clinical and research settings. METHODS: Global Delphi studies with experts in TMDs and in pain psychology identified ways of adapting the DC/TMD for children. RESULTS: The proposed adaptation is suitable for children aged 6-9 years. Proposed changes in Axis I include (i) adapting the language of the Demographics and the Symptom Questionnaires to be developmentally appropriate for children, (ii) adding a general health questionnaire for children and one for their parents, (iii) replacing the TMD Pain Screener with the 3Q/TMD questionnaire and (iv) modifying the clinical examination protocol. Proposed changes in Axis II include (i) for the Graded Chronic Pain Scale, to be developmentally appropriate for children, (ii) adding anxiety and depression assessments that have been validated in children and (iii) adding three constructs (stress, catastrophising and sleep disorders) to assess psychosocial functioning in children. CONCLUSION: The recommended DC/TMD, including Axis I and Axis II, for children aged 6-9 years, is appropriate for use in clinical and research settings. This adapted the first version for children includes changes in Axis I and Axis II changes requiring reliability and validity testing in international settings. Official translations to different languages according to INfORM requirements will enable a worldwide dissemination and implementation.

Who is the individual that will complain about temporomandibular joint clicking?

BACKGROUND: Understanding the profile of the individual complaining of TMJ clicking can help in the clinical approach of these patients. OBJECTIVE: To identify clinical variables associated with individuals who complain about and seek treatment for TMJ clicking. METHODS: Seventy-two individuals, composed the sample: Group 1 - patients with a complaint of TMJ clicking who sought treatment; (n = 36); Group 2 - individuals with TMJ clicking who have no complaints about it (n = 36). Three categories of data were evaluated: clinical (gender; age; side of TMJ clicking; TMJ pain; self-reported level of bother; previous TMJ clicking information); somatosensory (mechanical pain threshold [MPT], wind-up ratio [WUR], pressure pain threshold [PPT]); and, psychosocial (Pain Vigilance and Awareness Questionnaire [PVAQ]; Pain Catastrophising Scale [PCS]; Tampa Scale for Kinesiophobia for Temporomandibular Disorders [TSK/TMD]); The Perceived Stress Scale (PSS); The State-Trait Anxiety Inventory (STAI). RESULTS: Group 1 was composed mostly of female patients, with TMJ pain, without previous orientation about the condition, bothered by the clicking, with lower PPT and higher scores in the PVAQ, PCS, TKS/TMD, PSS and STAI scales than Group 2. The groups did not differ significantly for side of TMJ clicking, age, MPT and WUR. CONCLUSION: Individuals who have a TMJ clicking complaint and seek treatment are mostly female, have TMJ pain, have not received previous orientation about TMJ clicking, are bothered by the clicking, have a lower pain threshold and higher scores of hypervigilance, catastrophising, kinesiophobia, stress and anxiety than people with TMJ clicking who do not report it.

Evaluation of pain intensity in patients treated with aligners and conventional fixed appliances: Randomized clinical trial.

OBJECTIVE: This randomized clinical trial aimed to compare the pain intensity in patients treated with orthodontic aligners and conventional fixed appliances. SETTING AND SAMPLE POPULATION: This study was a randomized clinical trial. The sample comprised 39 patients randomly allocated into 2 groups: OA (orthodontic aligners, n = 20) and FA (Fixed Appliance, n = 19). MATERIAL AND METHODS: The pain intensity was measured by the visual analogue scale (VAS) in the following periods: T0 (baseline), T1 (seven days after appliance placement) and seven days after each return on the first (T2), third (T3) and sixth (T4) months. The following variables were also investigated in the baseline: conditioned pain modulation, anxiety levels, hypervigilance and catastrophizing. The VAS measurements between groups were compared by the Mann-Whitney test. Comparisons between periods within each group were performed by the Friedman test. Data regarding catastrophizing and hypervigilance were compared by the t test. All tests were applied at a significance level of 5%, with 95% confidence interval. RESULTS: Both groups presented similar levels of anxiety, hypervigilance, catastrophizing and conditioned pain modulation. Both groups did not differ concerning the pain intensity in all periods. The intragroup evaluation revealed statistical differences between days in the FA group at all moments evaluated, for the OA group, similar findings between days were found for the T1 evaluation; however, at the 6-month period (T4), the pain levels varied over these days without statistical difference. Higher levels of pain were observed in the first seven days after appliance placement. CONCLUSION: The pain intensity, usually mild, was not influenced by the appliance design, although different patterns of reported pain seem to occur between groups.

Influence of self-reported physical activity and sleep quality on conditioned pain modulation in the orofacial region.

OBJECTIVES: To evaluate the influence of self-reported physical activity and sleep quality on conditioned pain modulation (CPM) in the orofacial region. MATERIALS AND METHODS: Ninety healthy participants aged 18-50 years old were evenly distributed according to the level of physical activity into low, moderate, and high level. The classification of physical activity was based on modified criteria of the International Physical Activity Questionnaire (IPAQ), considering intensity, duration, and frequency of physical activity. The Pittsburgh Sleep Quality Index (PSQI) assessed sleep quality and the individuals were then classified as good or poor sleepers. CPM was assessed using the pressure pain threshold (PPT) of the anterior temporalis as test stimulus and hand immersion in hot water as conditioning stimulus. ANOVA was applied to the data and Tukey's posttest was applied when the main effects or interactions were significant (p < 0.050). RESULTS: There was no significant main effect of neither physical activity nor sleep quality on pain modulation. However, individuals who reported high level of physical activity and good quality of sleep had a greater pain modulation (- 0.60 ± 0.34) when compared with those who reported moderate (- 0.10 ± 0.25) and low level of physical activity (- 0.10 ± 0.52) and good sleep quality (p < 0.028). CONCLUSIONS: Pain modulation seems to be more efficient in individuals who report a good sleep quality and a high level of physical activity. CLINICAL RELEVANCE: Conditioned pain modulation is highly variable in healthy people. Therefore, a multifactorial approach should be taken into consideration in the evaluation of the efficacy of endogenous analgesia.

Clinical variables associated with the presence of articular pain in patients with temporomandibular joint clicking.

OBJECTIVE: To study and estimate the impact of clinical, somatosensory, and psychosocial variables associated with the concomitant presence of temporomandibular joint (TMJ) pain in patients with TMJ clicking. MATERIALS AND METHODS: Ninety-three individuals composed the sample: patients with painful TMJ clicking (n = 47) and patients with painless TMJ clicking (n = 46). Four categories of data were evaluated: clinical features (gender, maximal interincisal distance (MID), side of complaint, age); bruxism (sleep bruxism (SB), awake bruxism (AB)); somatosensory (mechanical pain threshold (MPT), wind-up ratio (WUR), pressure pain threshold (PPT), conditioned pain modulation (CPM)); and psychosocial (Pittsburgh Sleep Quality Index (PSQI), pain vigilance and awareness questionnaire (PVAQ), Pain Catastrophizing Scale (PCS), Tampa Scale for Kinesiophobia for Temporomandibular Disorders (TSK/TMD), Oral Behaviors (OBs)). RESULTS: Female gender, AB, WUR, CPM, PSQI, PCS, and OBs significantly (p < 0.05) increased the chance of the concomitant presence of TMJ pain in patients with TMJ clicking. On the other hand, MID, MPT, and PPT significantly (p < 0.05) decreased this chance. The other variables had no association. CONCLUSION: It can be concluded that being a woman, having AB, hyperalgesia in WUR, less efficient CPM, poor sleep quality, pain catastrophizing, and harmful OBs significantly increased the chance of the concomitant presence of TMJ pain in patients with TMJ clicking. In the opposite, high figures of MID, MPT, and PPT decreased the chance. CLINICAL RELEVANCE: Most patients with TMJ clicking usually postpone seeking treatment until the clicking truly disturbs or there is a concomitant presence of TMJ pain. Understanding the variables associated with this concomitance can be important in clinical practice.

Pain complications of oral implants: Is that an issue?

The use of oral implants as a form of replacing missing teeth in partial or total edentulous patients is considered the gold standard in oral rehabilitation. Although considered a history of success in contemporary dentistry, surgical complications may occur, as excessive bleeding, damage to the adjacent teeth and mandibular fractures. Persistent pain and abnormal somatosensory responses after the surgery ordinary healing time are also potential problems and may lead to the development of a condition named posttraumatic trigeminal neuropathic pain (PTNP). Though relatively rare, PTNP has a profound impact on patient's quality of life. Appropriated previous image techniques, effective anaesthetic procedures and caution during the surgical procedure and implant installation are recommended for the prevention of this condition. In case of the PTNP, different management modalities, including antidepressant and membrane stabilizer medications, as well as peripheral strategies, as the use of topical medication and the botulin toxin are presented and discussed.

Diagnostic criteria for temporomandibular disorders (DC/TMD) for children and adolescents: An international Delphi study-Part 1-Development of Axis I.

BACKGROUND: Since in children and adolescence prevalence is assessed mainly on self-reported or proxy-reported signs and symptoms; there is a need to develop a more comprehensive standardised process for the collection of clinical information and the diagnosis of TMD in these populations. OBJECTIVE: To develop new instruments and to adapt the diagnostic criteria for temporomandibular disorders (DC/TMD) for the evaluation of TMD in children and adolescents. METHOD: A modified Delphi method was used to seek international consensus among TMD experts. Fourteen clinicians and researchers in the field of oro-facial pain and TMD worldwide were invited to participate in a workshop initiated by the International Network for Orofacial Pain and Related Disorders Methodology (INfORM scientific network) at the General Session of the International Association for Dental Research (IADR, London 2018), as the first step in the Delphi process. Participants discussed the protocols required to make physical diagnoses included in the Axis I of the DC/TMD. Thereafter, nine experts in the field were added, and the first Delphi round was created. This survey included 60 statements for Axis I, and the experts were asked to respond to each statement on a five-item Likert scale ranging from 'Strongly disagree' to 'Strongly agree'. Consensus level was set at 80% agreement for the first round, and at 70% for the next. RESULTS: After three rounds of the Delphi process, a consensus among TMD experts was achieved and two adapted DC/TMD protocols for Axis I physical diagnoses for children and adolescents were developed. CONCLUSION: Through international consensus among TMD experts, this study adapted the Axis I of the DC/TMD for use in evaluating TMD in children and adolescents.

The effectiveness of microwave disinfection in treating Candida-associated denture stomatitis: a systematic review and metaanalysis.

OBJECTIVE: To evaluate the effectiveness of microwave disinfection in treating Candida-associated denture stomatitis (CADS). MATERIALS AND METHODS: The PubMed/MEDLINE, Embase, and Scopus databases were searched for reports on randomized clinical trials (RCTs) published in English until May 2020 (PROSPERO CRD42020192062) that evaluated the treatment of CADS by using microwave disinfection. The main outcomes were the improvement of clinical signs and/or the decrease in the residual yeast present on the dentures and palatal mucosa. The mean differences, standard deviations, risk ratio, and 95% confidence interval were calculated by using the random-effects model. Heterogeneity was assessed by using Cochran's Q test and I2 values. The level of significance was set at α = 0.05. RESULTS: Five RCTs with 245 participants were included. The descriptive investigations demonstrated that microwave disinfection was as effective (p > 0.05) as 0.2% chlorhexidine, 0.02% sodium hypochlorite, and topical nystatin (100.000 IU/mL), and was superior to topical miconazole in treating CADS. The metaanalysis did not show a statistical difference between microwave disinfection and nystatin (100.000 IU/mL) treatment in terms of mycological counts, cure, and recurrence rates (p > 0.05). CONCLUSION: Microwave disinfection showed comparable results with those of conventional therapies for treating CADS. In addition, treatment with 650 W for 3 min once a week for 14 days had better cost-effect results, indicating both the prevention and treatment of CADS. CLINICAL RELEVANCE: Our findings provide evidence regarding the treatment of CADS using microwave disinfection, and also indicating the best cost-effective option for this treatment modality.

Somatosensory and psychosocial profile of patients with painful temporomandibular joint clicking.

BACKGROUND: Determining the somatosensory and psychosocial profile of patients with painful temporomandibular joint (TMJ) clicking can help to understand the pain mechanisms in cases of TMJ clicking. OBJECTIVE: To characterise the somatosensory and psychosocial profile of patients with painful TMJ clicking when compared to patients with painless TMJ clicking and healthy control group. METHODS: Somatosensory and psychosocial functions were assessed in 90 individuals: patients with painful TMJ clicking (n = 30); patients with painless TMJ clicking (n = 30); and healthy controls (n = 30). Somatosensory profile included: mechanical pain threshold (MPT); wind-up ratio (WUR); pressure pain threshold (PPT); and conditioned pain modulation (CPM). Psychosocial profile included some questionnaires: Pittsburgh Sleep Quality Index (PSQI); Pain Vigilance-Awareness Questionnaire (PVAQ); Pain Catastrophizing Scale (PCS); Tampa Scale for Kinesiophobia (TSK); Perceived Stress (PSS); and State-Trait Anxiety Inventory (STAI). All variables were compared among all groups. RESULTS: Higher values of MPT and WUR; lower PPT; less efficient CPM; and higher scores of PSQI, PVAQ, PCS, and TSK were found in patients with painful TMJ clicking when compared to the other two groups (P < .001). Patients with painless TMJ clicking showed lower PPT and higher scores of PVAQ and TKS than the healthy control group. PSS and STAI data had no differences. CONCLUSION: Patients with painful TMJ clicking had abnormalities in the somatosensory profile, with a significant somatosensory gain of function (more sensitive) to mechanical pain tests and less efficient CPM. Poor sleep quality along with higher levels of hypervigilance, pain catastrophising, and kinesiophobia were features of psychosocial profile of these patients.

Association between painful temporomandibular disorders and sleep quality: A systematic review.

This review aimed to systematically evaluate the association between painful temporomandibular disorders (TMD) and sleep quality in adults. Observational case-control studies using either RDC/TMD or DC/TMD for TMD diagnostic and validated questionnaires for sleep quality were selected by two reviewers in a two-phase process. A systematic review was conducted in accordance with the PRISMA statement. The search was performed in PubMed/MEDLINE, LILACS, SCOPUS, PsycINFO, Web of Science and Grey literature (ProQuest, Google Scholar and OpenGrey). To be eligible, studies had to include adults (>18 years old), with no language, gender or time of publication restrictions. The quality of the papers was assessed using the Newcastle-Ottawa Scale (NOS). Eight case-control studies were included, with high (4) and moderate (4) quality assessment. Seven studies reported a significant association between the presence of painful TMD and sleep quality (P < .05), while the other found impaired sleep in participants with higher sensitivity to heat pain (P < .001). When pain levels were concerned, using different pain scales, six studies found differences when compared to control groups. One study showed that in non-painful TMD, the PSQI values were not different when compared to the control group. An association exists between painful TMD and sleep quality. The presence of pain seems to strongly impact the sleep quality in TMD patients.

Botulinum toxin type A applications for masticatory myofascial pain and trigeminal neuralgia: what is the evidence regarding adverse effects?

OBJECTIVES: The objective of the study was to conduct a systematic review of literature assessing botulinum toxin type A (BoNT-A) safety and adverse effects in the treatment of myofascial pain (MFP) and trigeminal neuralgia (TN). MATERIALS AND METHODS: The search for articles by two specific researchers involved the PubMed, EMBASE, Web of Science, and Scopus databases. Specific terms were used, and no publication time and language restrictions were applied. Clinical trials that investigated the effects of BoNT-A among participants with myofascial pain in masticatory muscles or trigeminal neuralgia were considered eligible for this systematic review. Data for each study were extracted and analyzed according to a PICO-like structured reading. RESULTS: The search strategy provided 436 citations. After analysis, 16 citations were included, seven for MFP and nine for TN. In all studies, BoNT-A was well tolerated and improved pain. The most common adverse effects were temporary regional weakness, tenderness over the injection sites, and minor discomfort during chewing. Most studies reported a spontaneous resolution of adverse effect. CONCLUSIONS: It can be concluded that BoNT-A treatment is well tolerated, since minor adverse effects were the most frequently reported; however, it is recommended that future studies aim to assess the safety and possible adverse effects of multiples applications or high doses of this treatment. CLINICAL RELEVANCE: BoNT-A has been increasingly diffused in dentistry, being used for the management of masticatory myofascial pain and trigeminal neuralgia. Nonetheless, there is no consensus about its efficacy and adverse effects that could occur when this treatment is applied.

Placebo and nocebo response magnitude on temporomandibular disorder-related pain: A systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review (SR) was to answer the following question: "In adult patients with temporomandibular disorder (TMD)-related pain, what is the placebo or nocebo effect of different therapies?" METHODS: A SR was performed with randomised clinical placebo-controlled trials on diagnosed painful TMD studies from five main databases and from three grey literature. Studies included must have sample older than 18 years, with painful TMD, which diagnosis was done by Research Diagnostic Criteria (RDC/TMD) or Diagnostic Criteria (DC/TMD). RESULTS: Out of 770 articles obtained, 42 met the inclusion criteria for qualitative and 26 for quantitative analysis. Meta-analysis indicated mean variation on pain intensity for placebo therapy was higher on laser acupuncture with 45.5 mm point reduction, followed by avocado soya bean extract with 36 mm and amitriptyline 25 mg with 25.2 mm. Laser showed a 29% of placebo effect, as well medicine with 19% and other therapies with 26%. Possible nocebo effect of 8% pain increase was found for intra-articular injection of Ultracain. CONCLUSIONS: Based on the available data, the placebo response could play a major effect on TMD pain management and may be responsible from 10% to 75% of pain relief. Laser acupuncture, avocado soya bean and amitriptyline promoted the higher placebo effect. Possible nocebo effect was found only for Ultracain injection with 8%. CLINICAL RELEVANCE: Clinicians could apply such evidence to optimise pain management and judgement about treatment efficacy, and researches may find it useful when designing their investigations.

Prevalence of psychosocial impairment in temporomandibular disorder patients: A systematic review.

BACKGROUND: Several studies have described high levels of psychosocial disorders in patients with temporomandibular disorders (TMD), but an estimate of their prevalence in populations of TMD patients has never been assessed systematically. OBJECTIVE: To conduct a systematic review of the literature on the prevalence of research diagnostic criteria for TMD (RDC/TMD) Axis II findings in TMD patients. METHODS: Search for articles was carried out by two independent researchers to retrieve papers published after 1992. Inclusion was reserved to observational studies with a minimum sample size of 100 individuals, which used RDC/TMD diagnostic protocol. Quality assessment was performed with the adoption of the methodological evaluation of observational research (MORE). RESULTS: A total of 1186 citations were obtained from search strategy, but only 14 filled the inclusion criteria. Included papers reported somatisation, depression and/or pain-related disability prevalence or scores from populations of 12 different countries. A broad range in the prevalence of moderate-to-severe somatisation in patients with TMD was observed, ranging from 28.5% to 76.6%. Similar results were found for depression, with moderate-to-severe levels in 21.4%-60.1% of patients. Finally, most patients were rated as grade I or II of the Graded Chronic Pain Scale, whereas high pain-related impairment was present in 2.6% to 24% of the individuals. CONCLUSION: The prevalence of severe-to-moderate somatisation and depression was high in TMD patients, while severe physical impairment was not commonly reported.

Reliability of the nociceptive blink reflex evoked by electrical stimulation of the trigeminal nerve in humans.

OBJECTIVE: The nociceptive blink reflex (nBR) can be useful to investigate trigeminal nociceptive function. The aim of this study was to estimate the reliability of the nBR evoked by electrical stimulation of the three branches of the trigeminal nerve under the following conditions: over time (test-retest and intrarater reliability) and by two examiners (interrater reliability). MATERIALS AND METHODS: Twenty-one healthy participants were evaluated in two sessions (24 h apart). The nBR was elicited by a so-called "nociceptive-specific" electrode placed over the entry zone of the right supraorbital (V1R), infraorbital (V2R), mental (V3R), and left infraorbital (V2L) nerve. The outcomes were individual electrical sensory (I 0) and pain thresholds (I P); root mean square (RMS), area-under-the-curve (AUC), and onset latencies of R2 responses (determined twice after a recalibration session); and stimulus-evoked pain on a 0-10 numerical rating scale. Intraclass correlation coefficients (ICCs) and Kappa statistics were computed (α = 5%). RESULTS: ICCs were fair to excellent in 82% of the psychophysical measures (fair 21%, good 31%, excellent 30%) and in 86% of V1R, V2R, and V2L nBR parameters, whereas 52% of V3R showed poor reliability. ICCs for intrarater reliability were fair to good in 70% of measurements (fair 20%, good 50%) and in 75% of interrater measurements after the recalibration (fair 55%, good 20%). All kappa values showed at least fair agreement and the majority of the nBR measures (93%) presented moderate to excellent reliability. CONCLUSION: The nBR and its associated psychophysical measures can be considered a sufficiently reliable test. CLINICAL SIGNIFICANCE: The nBR can be recommended as an electrophysiological technique to assess trigeminal nociceptive function.

Agreement of the International Classification of Sleep Disorders Criteria with polysomnography for sleep bruxism diagnosis: A preliminary study.

STATEMENT OF PROBLEM: Validated questionnaires and guidelines for assessing sleep bruxism (SB) that can be administered by dentists in clinical practice are still lacking. PURPOSE: The purpose of this preliminary study was to compare the third edition of the International Classification of Sleep Disorders (ICSD-3) criteria for diagnosing SB with the results of the gold standard polysomnography (PSG) examination. MATERIAL AND METHODS: Twenty consecutive postgraduate students and staff at Bauru School of Dentistry, University of São Paulo, Bauru, Brazil, participated. Each participant underwent interview, clinical assessment, and a PSG evaluation. Bruxers and nonbruxers were identified based only on the PSG analysis. The validity of the ICSD-3 criteria was assessed by receiver operating characteristics curve analysis, area under the curve (AUC), likelihood ratios (LR), and the diagnostic odds ratio (DOR). RESULTS: The ICSD-3 diagnostic criteria items for SB had fair to moderate concordance with the PSG diagnosis, with AUC ranging from 0.55 to 0.75. The best value of agreement was the association of SB more than once a week with transient morning jaw muscle pain or fatigue with a moderate but significant agreement with the PSG diagnosis of SB (AUC=0.75), with 90% specificity, positive LR=6, and DOR=13.5. When the frequency of self-reported SB increased to more than 4 times a week, the combination of this finding with tooth wear also had high values of agreement with the PSG diagnosis of SB (AUC= 0.75, +LR=6, DOR=13.6). CONCLUSIONS: The report of regular or frequent SB and the presence of (1) incident of abnormal tooth wear or (2) incidents of transient morning jaw muscle pain or fatigue were the best discriminatory items of ICSD-3 for SB diagnosis.