The analgesic effect of crotoxin on neuropathic pain is mediated by central muscarinic receptors and 5-lipoxygenase-derived mediators

Crotoxin (CTX). a neurotoxin isolated from the venom of the South American rattlesnake Crotalus durissus terrificus. induces analgesia. In this study, we evaluated the antinociceptive effect of CTX in a model of neuropathic pain induced by rat sciatic nerve transection. Hyperalgesia was detected 2 h after nerve transection and persisted for 64 days. Immersion of proximal and distal nerve stumps in CTX solution (0.01 mM for 10 s), immediately after nerve transection, blocked hyperalgesia. The antinociceptive effect of CTX was long-lasting, since it was detected 2 h after treatment and persisted for 64 days. CTX also delayed, but did not block, neurectomy-induced neuroma formation. The effect of CTX was blocked by zileuton (100 mg/kg, p.o.) and atropine (10 mg/kg. i.p.), and reduced by yohimbine (2 mg/kg, i.p.) and methysergide (5 mg/kg, i.p.). on the other hand. indomethacin (4 mg/kg, i.v.). naloxone (1 mg/kg, i.p.). and N-methyl atropine (30 mg/kg, i.p.) did not interfere with the effect of CTX. These results indicate that CTX induces a long-lasting antinociceptive effect in neuropathic pain, which is mediated by activation of central muscarinic receptors and partially, by activation of alpha-adrenoceptors and 5-HT receptors. Eicosanoids derived from the lipoxygenase pathway modulate the action of crotoxin. (C) 2008 Elsevier B.V. All rights reserved.

Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: a systematic review

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Different substances and dry-needling injections in patients with myofascial pain and headaches

Trigger point injections with different solutions have been studied mainly with regard to the management of myofascial pain (MFP) patient management. However, few studies have analyzed their effect in a chronic headache population with associated MFP. The purpose of this study was to assess if trigger point injections using lidocaine associated with corticoid would be better than lidocaine alone, as in comparison with dry-needling in for the management of local pain and associated headache management. Forty-five (45) myofascial pain patients with headaches that could be reproduced by activating at least one trigger point, were randomly assigned into one of the three groups: G1, dry-needling, G2, 0.25% lidocaine, at 0.25% and G3, 0.25% lidocaine at 0.25% associated with corticoid, and were assessed during a 12 week period. Levels of pain intensity, frequency and duration, local post-injection sensitivity, obtainment time and duration of relief, and the use of rescue medication were evaluated. Statistically, all three groups showed favorable results for the evaluated requisites (p <= 0.05), but only for post-injection sensitivity did the association of lidocaine with corticoid present the best results and ingestion of rescue medication.

Myofascial Pain Syndrome as a Contributing Factor in Patients with Chronic Headaches

Objectives: The purpose of this study was to evaluate the prevalence of active and latent trigger points [TrPs], as well as analyze the prevalence of different types of headaches in chronic headache patients. The active and latent TrPs in muscles of orofacial and cervical regions were also evaluated. Methods: There were 290 subjects who participated in this study. Trigger points were identified according to Simons et al.'s diagnostic criteria. Trigger points were considered active if subjects recognized the evoked referred pain as their familiar headache. If the evoked referred pain was not recognized as the familiar headache, the TrPs were considered latent. Differential diagnosis for headache was performed on the basis of International Headache Society criteria. Results: Trigger points could be diagnosed in 77 percent of patients and, in 89 percent of these, active TrPs were found. Muscle tenderness could be observed in 22 percent of patients, and only 1 percent patients were muscle-pain-free. The headache diagnosis showed that 26 percent had tension-type headache, 13 percent had migraine, and 61 percent had combined episodes of tension-type headache and migraine. The highest number of TrPs were found in temporalis [N = 159], masseter [N = 126], and occiptofrontalis [N = 113] muscles. Active TrPs were more frequent in temporalis and occiptofrontalis muscles. Conclusions: Subjects with chronic headaches had a higher prevalence of TrPs, and headache complaints could be reproduced during stimulation of active TrPs that were localized more frequently in temporalis and occiptofrontalis muscles. The presence of TrPs may be a contributing factor in the initiation and/or perpetuation of chronic headaches.

A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Topical effect of propolis in the repair of sulcoplasties by the modified Kazanjian technique. Cytological and clinical evaluation.

A study was conducted to analyze the effects of propolis mouth rinse on the repair of surgical wounds after sulcoplasty by the modified Kazanjian technique. Twenty-seven patients who underwent sulcoplasty were divided into three groups: C1--patients who did not use the mouth rinse C2--patients who used a mouth rinse containing 5% aqueous alcohol T--patients who used a mouth rinse containing 5% propolis in aqueous alcohol solution. The patients returned 7, 14, 30, and 45 days after surgery for cytological and clinical evaluation. It was concluded that: 1) the mouth rinse containing propolis in aqueous alcohol solution aids repair of intra-buccal surgical wounds and exerts a small pain-killing and anti-inflammatory effect; 2) the vehicle employed has a minor irritant effect on intra-buccal surgical wounds; 3) exfoliative cytology allows epithelization of intrabuccal surgical wounds.

Therapeutic response of benzodiazepine, orphenadrine citrate and occlusal splint association in TMD pain

Loss of function, muscle inflammation, and pain are some of the signs and symptoms of temporomandibular dysfunction (TMD). Pharmacological strategies to minimize the clinical manifestation of these disorders often focus on blocking or inhibiting the pain-causing symptom. Resources such as muscle-relaxants, anxiety-relief drugs, and splint therapy are often used to reduce muscular hyperactivity related to TMD muscle pain. This study compares the effect of a randomly ordered association of occlusal splint therapy (S), nonsteroid anti-inflammatory with a muscle-relaxant drug (orphenadrine citrate) (O), and an anxiety-relief drug (benzodiazepine) (B), to ease painful TMD muscle symptoms. Clinical and anamnestic analyses were recorded in accordance with the Helkimo TMD index and applied before and after treatments. Twenty-one group two Helkimo TMD adult female patients were treated, all of whom were subjected to the three random therapeutic associations proposed: SBO, BOS, and OSB. The same operator applied the three specific associations over a period of 21 days in the proposed sequence, seven days for each therapy. The results show that all the groups presented the best results in terms of relief from pain after the therapeutic association (28.5% showed a decrease and 47.6% showed an absence of symptoms). No significant difference was observed among association therapeutic protocols. Copyright © 2003 by CHROMA, Inc.

Clinical evaluation of amitriptyline for the control of chronic pain caused by temporomandibular joint disorders

Temporomandibular disorder (TMD) is characterized by a combination of symptoms affecting the temporomandibular joint and/or chewing muscles. The two most common clinical TMD symptoms are pain and dysfunction. Pain is usually caused by dysfunction, and emergency therapy has focused on controlling it. Recent investigations into TMD have led to the recommendation of antidepressants as a supporting treatment against constant neuralgic pain. The aim of this double-blind study was to verify the efficiency of antidepressants (amitriptyline) as a support in the treatment of chronic TMD pain. Twelve female volunteers presenting chronic TMD pain were divided into two groups and treated for 14 days: Group 1 with 25 mg/day of amitriptyline and Group 2 with a placebo. The intensity of pain and discomfort was evaluated daily, using a visual analog scale (VAS), over a period of seven days preceding the treatment (baseline), during the 14-day treatment, and for seven days after the treatment. The results revealed a significant reduction of pain and discomfort in Group 1 (75%) compared to Group 2 (28%) during the three weeks beginning at baseline (p< 0.01). Amitriptyline proved to be an efficient alternative treatment for chronic pain in TMD patients. Copyright © 2003 by CHROMA, Inc.

Effect of diclofenac sodium on the healing process of end-to-end anastomosis in carotid arteries of rabbits. Histopathological and biomechanical studies

Aim. Diclofenac sodium is a non-steroidal anti-inflammatory drug commonly used to attenuate painful inflammatory reactions in surgery. However, it may delay healing in the skin and gastrointestinal tract. The aim of this study was to evaluate the influence of Diclofenac in vascular healing. Methods. Ninety rabbits had their carotid arteries sectioned and reconstructed by end-to-end anastomosis with interrupted sutures. The animals were randomly allocated into 3 groups of 30 each and treated by intramuscular route with saline (control), 5 mg/kg/day of diclofenac sodium (DS-5), and 10 mg/kg/day of diclofenac sodium (DS-10). Treatment began on the day of surgery and lasted 4 days. Angiography, biomechanical properties (failure load, failure elongation, yield point, yield point elongation, and stiffness were obtained from the load/elongation curve), macroscopic and histological examinations (hematoxylin-eosin, Masson, Calleja, Picrossirius-red), and scanning electron microscopy were studied in both arteries on the 3rd and 15th postoperative days. Results. No significant differences in biomechanical properties were observed either in the 3 groups or the experimental times. The carotid artery healing process was similar in the 3 groups. Conclusion. Diclofenac sodium did not cause alterations nor delayed carotid artery healing.

Evaluation of microcurrent electrical nerve stimulation (mens) effectiveness on muscle pain in temporomandibular disorders patients

The effect of Microcurrent Electrical Nerve Stimulation (MENS) was evaluated and compared with occlusal splint therapy in temporomandibular disorders (TMD) patients with muscle pain. Twenty TMD patients were divided into four groups. One received occlusal splint therapy and MENS (I); other received splints and placebo MENS (II); the third, only MENS (III) and the last group, placebo MENS (IV). Sensitivity derived from muscle palpation was evaluated using a visual analogue scale. Results were submitted to analysis of variance (p<0.05). There was reduction of pain level in all groups: group I (occlusal splint and MENS) had a 47.7% reduction rate; group II (occlusal splint and placebo MENS), 66.7%; group III (MENS), 49.7% and group IV (placebo MENS), 16.5%. In spite of that, there was no statistical difference (analysis of variance / p<0.05) between MENS and occlusal splint therapy regarding muscle pain reduction in TMD patients after four weeks.

Sleep bruxism: Clinical aspects and characteristics in patients with and without chronic orofacial pain

Objective. Evaluation of long-standing sleep bruxism (SB) patients. Study Design. Descriptive study. Results. One hundred subjects with SB (80 women and 20 men, mean age: 36.1±11.3 years) were evaluated according to the RDC/TMD and a pain questionnaire (EDOF-HC). The patients were divided into 2 groups: Group A-without (30.0%) and Group B-with orofacial pain (70.0%). AM stiffness: 36.4% in Group A and 88.6% in Group B; mean pain duration: 6.92 years; mean intensity of pain: 4.33 (VAS); quality of pain: tightness/pressure (84,3%); 95.7% of Group B had myofascial pain. Depression and somatization levels were different between the groups (p = 0.001). Higher frequency of depression was found with body pain or presence of comorbidities. Conclusion. The data presented in this study showed statistical differences between long-standing bruxism without and with chronic facial pain; the two questionnaires allowed interaction between the chief complaint and the clinical findings; depression levels increased with pain in several regions of the body. © 2006 Elsevier Inc. All rights reserved.