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Introduction: Bruxism is defined as a repetitive masticatory muscle activity that can manifest it upon awakening (awake bruxism‐AB) or during sleep (sleep bruxism‐SB). Some forms of both, AB and SB can be associated to many other coexistent factors, considered of risk for the initiation and maintenance of the bruxism. Although controversial, the term 'secondary bruxism' has frequently been used to label these cases. The absence of an adequate definition of bruxism, the non‐distinction between the circadian manifestations and the report of many different measurement techniques, however, are important factors to be considered when judging the literature findings. The use (and abuse) of drugs, caffeine, nicotine, alcohol and psychoactive substances, the presence of respiratory disorders during sleep, gastroesophageal reflux disorders and movement, neurological and psychiatric disorders are among these factors. The scarcity of controlled studies and the complexity and interactions among all aforementioned factors, unfortunately, does not allow to establish any causality or temporal association with SB and AB. The supposition that variables are related depends on different parameters, not clearly demonstrated in the available studies. Objectives: This narrative review aims at providing oral health care professionals with an update on the co‐risk factors and disorders possibly associated with bruxism. In addition, the authors discuss the appropriateness of the term 'secondary bruxism' as a valid diagnostic category based on the available evidence. Conclusion: The absence of an adequate definition of bruxism, the non‐distinction between the circadian manifestations and the report of many different measurement techniques found in many studies preclude any solid and convincing conclusion on the existence of the 'secondary' bruxism. [ABSTRACT FROM AUTHOR]

Introduction: The influence of aligners on the activity of the masticatory muscles is still controversial, especially regarding the behaviour associated with awake bruxism (AB). Objective: To compare the frequency of AB behaviours between patients treated with aligners and fixed appliances. Methods: The sample comprised 38 Class I patients (mean age 22.08 years), divided by simple randomisation into two groups: OA group; orthodontic aligners (n 19) and FA group; fixed appliance (n 19). The frequency of AB was investigated by the ecological momentary assessment using an online device (mentimeter), during 7 following days at different timepoints, before and after appliance placement and in the 2nd, 3rd, 4th and 6th months of orthodontic treatment. These variables were also evaluated: level of anxiety by the State‐Trait Anxiety Inventory, stress by the Perceived Stress Scale, catastrophising related to pain and degree of hypervigilance by the Pain Vigilance and Awareness Questionnaire, and the presence of facial pain evaluated by the DC/TMD. Results: There was no difference between groups in the frequency of AB behaviours, with mean of 53.5% for group OA and 51.3% for FA. The most frequent behaviour was slightly touching the teeth, and in FA group, there was a significant reduction in this behaviour soon after appliance placement. The groups did not differ concerning the degree of anxiety, stress, catastrophising, hypervigilance and facial pain. Conclusion: The orthodontic treatment performed with aligners or fixed appliances did not influence the frequency of AB during the 6 months of treatment. Registry of Clinical Trials: (REBEC): RBR‐9zytwf. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the influence of self-reported physical activity level on painful mechanical somatosensory profile and psychosocial characteristics. Methods: A total of 90 participants, male and female, were divided into three groups based on the frequency, duration, and intensity of physical activity over the last 3 months. The classification followed a modified criterion of the short version of the International Physical Activity Questionnaire (IPAQ). Mechanical quantitative sensory tests were performed in the region of the anterior temporalis muscle and on the thenar area of the dominant hand, and psychosocial aspects were assessed using questionnaires measuring state and trait anxiety, pain catastrophizing, lifestyle, and quality of life. Results: There was no significant main effect of group on any of the somatosensory variables (F < 0.34 and P > .416). As for psychosocial aspects, the low level of physical activity group had the lowest scores on the lifestyle questionnaire (P < .009). Conclusion: Level of physical activity did not significantly influence mechanical somatosensory thresholds or temporal summation in the orofacial region, and worse quality of life was found in participants reporting a low level of physical activity. [ABSTRACT FROM AUTHOR]

Background: Changes in quantitative sensory testing (QST) parameters following topical anaesthesia could contribute to better elucidate underlying mechanisms of somatosensory alterations in temporomandibular disorder (TMD) pain patients. This placebo‐controlled crossover investigation compared the somatosensory profile following topical anaesthesia between TMD patients (n = 20) and healthy participants (n = 20). Methods: Cold detection threshold, warm detection threshold, cold pain threshold, heat pain threshold, mechanical detection threshold, mechanical pain threshold, wind‐up ratio and pressure pain threshold were assessed on the skin overlying the masseter at three consecutive days (baseline and immediately after lidocaine 4%/placebo cream). Mixed ANOVA and a coding system that accounts for the diversity of types of peripheral axons associated with the somatosensory parameters were applied for data analysis. Results: The lidocaine application caused no changes in the somatosensory sensitivity in the masseter region in TMD patients (P >.050), but sensitivity to cold, cold pain, touch and pinprick stimuli were reduced after topical anaesthesia in healthy participants (P <.050). Also, the degree of topical anaesthesia was greater in healthy participants (P =.008). The coding system suggested that TMD patients presented only Aδ‐fibre block, whereas a combination of either Aβ‐ and/or C‐fibre block was observed in 35% of healthy participants in addition to Aδ‐fibre block following lidocaine application. Conclusion: Quantitative sensory testing can be successfully applied to identify meaningful differences in the degree of hypoalgesia and hypoesthesia following short‐time topical anaesthesia. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the antinociceptive effects of citronellal (CTL) on formalin-, capsaicin-, and glutamate-induced orofacial nociception in mice and to investigate whether such effects might involve a change in neural excitability. Methods: Male mice were pretreated with CTL (50, 100, and 200 mg/kg, ip), morphine (5 mg/kg, ip), or vehicle (distilled water + one drop of Tween 80 0.2%) before formalin (20 μL, 2%), capsaicin (20 μL, 2.5 μg) or glutamate (40 μL, 25 μM) injection into the right vibrissa. Sciatic nerve recordings were made using the single sucrose gap technique in rats. The data obtained were analyzed by ANOVA followed by Dunnett's test for the behavioral analyses and by the Student t test for CAP evaluation. Results: Pretreatment with CTL was effective in reducing nociceptive face-rubbing behavior in both phases of the formalin test, which was also naloxone-sensitive. CTL produced significantly antinociceptive effect at all doses in the capsaicin- and glutamate- tests. Rota-rod testing indicated that such results were unlikely to be provoked by motor abnormality. Recordings using the single sucrose gap technique revealed that CTL (10 mM) could reduce the excitability of the isolated sciatic nerve through a diminution of the compound action potential amplitude by about 42.4% from control recordings. Conclusion: These results suggest that CTL might represent an important tool for management and/or treatment of orofacial pain. [ABSTRACT FROM AUTHOR]

The aim of this study was assess the effect of collagen-based films containing usnic acid as a wound dressing for dermal burn healing. Second-degree burn wounds were performed in forty-five Wistar rats, assigned into nine groups: COL--animals treated with collagen-based films; PHO--animals treated with collagen films containing empty liposomes; UAL--animals treated with collagen-based films containing usnic acid incorporated into liposomes. After 7, 14, and 21 days the animals were euthanized. On 7th day there was a moderate infiltration of neutrophils, in UAL, distributed throughout the burn wounds, whereas in COL and PHO, the severity of the reaction was slighter and still limited to the margins of the burn wounds. On the 14th day, the inflammatory reaction was less intense in UAL, with remarkable plasma cells infiltration. On the 21st day, there was reduction of the inflammation, which was predominantly composed of plasma cells in all groups, particularly in UAL. The use of the usnic acid provided more rapid substitution of type-III for type-I collagen on the 14th day, and improved the collagenization density on the 21st day. It was concluded that the use of reconstituted bovine type-I collagen-based films containing usnic acid improved burn healing process in rats., 1. Introduction Disruption of the skin generally leads to an increased fluid loss, infection, hypothermia, scarring, compromised immunity, and change in body image; furthermore, large skin damage can cause mortality [...]

Summary: Background: Although inflammation can alter cytokines release and nerve function, it is not yet fully established if orthodontic‐induced inflammation can cause significant extraoral trigeminal somatosensory alterations and release of inflammatory chemical mediators. Objective: The primary aim of this study was to investigate the impact of orthodontic separator and short‐term fixed orthodontic appliance on the extraoral trigeminal somatosensory function and concentrations of cytokines in the gingival crevicular fluid (GCF). Methods: Twenty‐two female patients were evaluated as follow: baseline, 24 hour‐after elastomeric separator (‐aES), 24 hour‐ and 1 month‐after bonding brackets (‐aBB) at both arches. The outcome variables were as follows: self‐reported pain (Visual Analog Scale), QSTs (current perception threshold‐CPT, cold detection threshold‐CDT, warm detection threshold‐WDT, mechanical detection threshold‐MDT, mechanical suprathreshold‐MST and wind‐up ratio‐WUR. All QSTs were performed at infra‐orbital and mental nerve entry zone at patient's dominant side. In addition, GCF samples in order to assess cytokines profile (IL‐1β,IL‐8,IL‐6 and TNF‐α) were collected. ANOVA and Tukey's post hoc analyses were performed (a = 5%). Results: Patients reported higher pain intensity 24 hour‐aBB compared to baseline and 24 hour‐aES (P < 0.050). Patients were less sensitive to pin‐prick pain (MST) at 24 hour‐aBB and 1 month‐aBB compared to baseline (P < 0.006). Significant increases in IL‐6 levels were observed 24 hour‐aBB (P < 0.001). Multiple comparison analysis showed significant increase in IL‐1β levels (P < 0.001) and TNF‐α (P < 0.001) 1 month‐aBB compared to baseline. Conclusion: Elastomeric separators only induced mild pain and were not able to significantly increase proinflammatory cytokines level in the GCF. In addition, orthodontic fixed appliance may induce only minor somatosensory changes at extraoral trigeminal locations. [ABSTRACT FROM AUTHOR]

The present study investigated the antinociceptive, anti-inflammatory and antioxidant effects of the leaf essential oil (LEO) of Cymbopogon winterianus Jowitt (Poaceae). In the acetic acid-induced writhing and formalin tests, the LEO (50, 100, and 200 mg/kg, p.o.) significantly reduced (p < 0.05) the number of writhings and paw licking times in the first (0-5 min) and second (15-30 min) phases, respectively. In contrast, the LEO did not alter the latency time for mice licking the rear paws in hot-plate test. The LEO inhibited the carrageenan-induced neutrophil migration to the peritoneal cavity in a dose-dependent manner (35.5%, 42.8%, and 66.1% at doses of 50, 100, and 200 mg/kg, respectively, p < 0.001). Moreover, LEO exhibited higher scavenging activity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with an IC50 (12.66 ± 0.56 μg/mL). Our present results demonstrated that the LEO has antinociceptive, anti-inflammatory, and antioxidant properties. [ABSTRACT FROM AUTHOR]

We investigated the antinociceptive and nerve excitability effects of the N-salicyloyltryptamine (NST) NST-treated mice exhibited a significant decrease in the number of writhes when 100 and 200 mg/kg (i.p.) were administered (i.p.). This effect was not antagonized by naloxone (1.5 mg/kg, i.p.). NST inhibited the licking response of the injected paw when 100 and 200 mg/kg were administered (i.p.) to mice in the first and second phases of the formalin test. Because the antinociceptive effects could be associated with neuronal excitability inhibition, we performed the single sucrose gap technique and showed that NST (3.57mM) significantly reduced (29.2%) amplitude of the compound action potential (CAP) suggesting a sodium channel effect induced by NST. Our results demonstrated an antinociceptive activity of the NST that could be, at least in part, associated to the reduction of the action potential amplitude. NST might represent an important tool for pain management. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to find out the prevalence of temporomandibular disorder (TMD) in a sample of university students and its relationship to gender, occlusion, and psychological factors. Materials and Methods: The sample comprised 196 subjects, aged 18-25 years. The TMD degree was evaluated using an anamnestic questionnaire. Morphologic occlusion was evaluated according to Angle classification (classes I, II, and III). The Hospital Anxiety and Depression Scale (HADS), a 14-item self-administered rating scale developed specifically to identify anxiety and depression in nonpsychiatric medical outpatients, was used to assess the levels of anxiety (HADSa) and depression (HADSd). Statistical Analysis: The incidence of TMD level, malocclusion, anxiety, and depression in both genders was calculated as percentages. Association between TMD degree and occlusion, HADSa, and HADSd was tested using the Chi-square test. Results: According to our results, 50% of the subjects had TMD, but it was of moderate or severe degree in only 9.18% of them. No statistically significant association could be found between TMD and gender or occlusion. TMD was found to have statistically significant association with HADSa but not with HADSd. Conclusion: A high prevalence of TMD was found in this student population; however, most of the cases could be classified as mild. Of the variables studied, only HADSa had a statistically significant association with TMD. [ABSTRACT FROM AUTHOR]

This work aimed to characterize and evaluate the antihypertensive effect of the (-)-β-pinene/β-cyclodextrin (βP/β-CD) complex. The complex was prepared through physical mixture and slurry complexation methods and was analyzed through differential scanning calorimetry, thermogravimetry/derivative thermogravimetry, fourier transform infrared spectroscopy, diffraction X-ray, docking and scanning electron microscopy. Normotensive or L-NAME-induced hypertensive rats were used in pharmacological experiments. Mean arterial pressure (MAP) was determined with direct blood pressure measurements from the abdominal aorta. The drugs were orally administrated and their effects were recorded during 48 hours. Vascular effects of βP were evaluated in isolated ring of mesenteric artery. The physicochemical characterization showed βP/β-CD complex formation. In hypertensive rats (MAP = 156±16 mmHg), the complex, but not βP alone, promoted hypotension at 36 and 48 hours after administration (MAP = 124±3 and 110±5 mmHg, respectively). In arterial rings, βP vasorelaxed rings precontracted with phenylephrine (Emax = 105±6%), which was not changed after the removal of the vascular endothelium (Emax = 108±4%), after the pre-contraction with KCl 80 mM (Emax = 107±8%) or S(-)-BayK8644 (Emax = 107±5%), or after incubation with TEA (Emax = 113±4%). Finally, βP inhibited CaCl2- and sodium-orthovanadate-induced contractions. In conclusion, the slurry complexation method was the best among them. Pharmacological results demonstrated that the complex promoted antihypertensive effect. Furthermore, βP induced endothelium- independent vasorelaxation possibly caused by the inhibition of the Ca2+ influx through L-type Ca2+ channel associated to a decrease in calcium sensitivity.