Chronic orofacial pain

The issues specific to trigeminal pain include the complexity of the region, the problematic impact on daily function and significant psychological impact (J Dent, 43 , 2015, 1203). By nature of the geography of the pain (affecting the face, eyes, scalp, nose, mouth), it may interfere with just about every social function we take for granted and enjoy (J Orofac Pain, 25 , 2011, 333). The trigeminal nerve is the largest sensory nerve in the body, protecting the essential organs that underpin our very existence (brain, eyes, nose, mouth). It is no wonder that pain within the trigeminal system in the face is often overwhelming and inescapable for the affected individual.     

����ؽڼ��������ʹ������

疼痛治疗分为药物治疗和非药物治疗。药物治疗包括非甾体类抗炎药、阿司匹林和扑热息痛等非阿片类镇痛药、阿片类镇痛药、"辅助"药物如抗抑郁药阿米替林和抗惊厥药卡马西平等。非药物治疗包括神经刺激疗法、神经阻滞疗法、外科手术、物理治疗、心理-行为疗法等。本文介绍我们临床上常见的颞下颌关节骨关节炎、肌筋膜疼痛、神经病理性疼痛(非典型牙痛、治疗后神经痛、三叉神经痛)及复合性局部疼痛综合征的主要临床用药和理论基础,如非甾体类抗炎药特异性COX-2抑制剂、改善骨关节炎症状和关节结构的药物硫酸氨基葡萄糖、阿片类药物曲马多、三环类抗抑郁药阿米替林、新一代抗惊厥药加巴喷丁等。     

Prevalence of cervical spinal pain in craniomandibular pain patients

It has often been suggested that patients with a craniomandibular disorder (CMD) more often suffer from a cervical spine disorder (CSD) than persons without a CMD. However, in most studies no controlled, blind design was used, and conclusions were based on differing signs and symptoms. In this study, the recognition of CMD and CSD was based upon the presence of pain. The aim of this study was to determine the prevalence of cervical spinal pain in persons with or without craniomandibular pain, using a controlled, single-blind design. From 250 persons, a standardised oral history was taken, and a physical examination of the masticatory system and the neck was performed. Three classification models were used: one based on symptoms only; a second on signs only; and a third one based on a combination of symptoms and signs. The CMD patients were also subdivided in three subgroups: patients with mainly myogenous pain; mainly arthrogenous pain; and both myogenous and arthrogenous pain. Craniomandibular pain patients more often showed cervical spinal pain than persons without craniomandibular pain, independent of the classification model used. No difference in the prevalence of cervical spinal pain was found between the three subgroups of craniomandibular pain patients.     

Comparison of pain thresholds and pain tolerance levels between Middle Easterners and Swedes and between genders

Summary  Objective: This study evaluates the presence of culture and gender differences in pain thresholds and pain tolerance levels between Middle Easterners and Swedes. Methods: Sixty-four healthy individuals, 32 Middle Easterners (16 men and 16 women, mean age: 24·6 ± 3·4 years) and 32 Swedes (16 men and 16 women, mean age: 24 ± 3·5 years) participated in the study. Three experimental pain tests were conducted in each participant. Pain thresholds and pain tolerance levels were measured using an algometer (mechanical stimulus), the PainMatcher^® (electric stimulus) and cold pressor test (thermal stimulus). Results: While no significant differences in pain thresholds were observed between Middle Easterners and Swedes in algometer and cold pressor tests, differences in pain tolerance levels were significant ( P  < 0·01 for both tests). All between-culture differences in pain perception, pain threshold and pain tolerance level were non-significant when measured with the PainMatcher. Significant between-gender differences were observed only in pain threshold with the PainMatcher ( P  <   0·05) and in pain tolerance level with the algometer ( P  <   0·01) and the PainMatcher ( P  <0·001). Conclusion: This study found significant differences in two out of three pain tolerance level tests – but not pain threshold tests – between the Middle Eastern and Swedish cultures and between genders. These differences were more pronounced between Middle Eastern and Swedish men than between Middle Eastern and Swedish women. Gender differences were more pronounced within the Swedish than the Middle Eastern culture. These findings indicate that culture and gender influence pain experience.     

Clinical examination of patients with orofacial pain

Abstract A thorough clinical examination of patients with orofacial pain is of paramount importance. The examination is time-consuming, but is usually fully rewarding in that it may prevent unnecessary or incorrect and often irreversible treatment, and clarify to the clinician and hopefully to the patient the nature of the patient's problem. Only then may proper treatment be rendered. In this context it should be noted that a skillfully performed examination in these patients in itself provides valuable and effective treatment, especially when muscular dysfunction is the primary cause of the pain.     

The measurement of human pain

Abstract The assessment of human pain is complicated not only because pain, like other sensory experiences, is subjective, but also because pain, unlike other sensory experiences, may be modified by psychological, social, and situational factors. These factors can modify the neuronal response evoked by a relatively constant noxious stimulus (such as an injection) so that the resulting pain sensation may be enhanced or reduced. Consequently, in order to measure pain accurately, investigators must attempt to assess the subjective experience of pain. Although there are observational, self-report, behavioral, and physiological methods available for measuring pain, direct scaling techniques may constitute a comprehensive measure by providing qualitative and quantitative estimates of pain expressed in terms of a patient's perception. A patient may rate both the strength and the affective dimensions of their clinical pain using simple measurement techniques that have been validated in well-controlled studies on experimental pain. Direct scaling throughout a range of stimulus intensities (experimental pain) or throughout a range of time intervals (clinical pain) also provides a framework for standardization of individual responses. This standardization facilitates rigorous evaluation of analgesic efficacy for different pharmacological methods and for different pain conditions. The requirements for an objective measure of pain are similar to the requirements for any measuring instrument. These are: 1) reliability – that the procedure yields consistent results over time; 2) validity – that the procedure measures unequivocally a specific dimension of pain; 3) minimum inherent bias – that the procedure is relatively independent of method bias or patient/investigator response bias; and 4) versatility – that the procedure is applicable for both laboratory and clinical use and is practical for a wide variety of different medical settings. Visual analog scales, a direct scaling method in which a patient adjusts the length of a line so that the length is proportional to their pain, have been validated in a variety of experimental and clinical pain studies. Although these scales are deceptively simple, they have the reliability, validity, and versatility necessary for an objective pain measure.     

正畸治疗疼痛的研究进展

疼痛是正畸治疗中最常见的问题之一,随着患者对治疗舒适度要求的增加,如何认识正畸治疗中的疼痛特点,如何减轻正畸治疗的疼痛程度,成为正畸医师关注的研究热点.本文就正畸治疗时疼痛的特点和减轻疼痛方法的研究进展作一综述.     

Patients’ experiences of supervised jaw-neck exercise among patients with localized TMD pain or TMD pain associated with generalized pain

Objective: To evaluate temporomandibular disorder (TMD) patients’ experiences of a supervised jaw-neck exercise programme.

Materials and methods: The study used a mixed method design. All patients were diagnosed with myalgia according to the Research Diagnostic Criteria for TMD and divided into local myalgia (n?=?50; 38 women, mean age 43 yrs, SD 14), and myalgia with generalized pain (n?=?28; 27 women, mean age 43 yrs, SD 13). Patients participated in a ten-session supervised exercise programme that included relaxation, coordination and resistance training of the jaw, neck and shoulders. After the 10 sessions an evaluation form was filled out including both open- and closed-ended questions. The quantitative analysis was based on closed-ended questions concerned experience, adaptation and side-effects from the exercise programme. The qualitative analysis was employing inductive content analysis of open-ended questions.

Results: Patients reported similar positive overall experiences of exercise regardless of diagnosis, although more individuals in the general pain group experienced pain during training (57%) compared to the local pain group (26%; p?=?.015). Patients in both groups shared similar experiences and acknowledged the possibility to participate in an individualized and demanding exercise programme. They expressed feelings of being noticed, taken seriously and respectful care management to be key factors for successful treatment outcome. The exercise programme was acknowledged as a valuable part of treatment.

Conclusion: The hypothesis generated was that individualized and gradually demanding exercise in the rehabilitation process of TMD stimulates self-efficacy and confidence in chronic TMD patients regardless of whether the pain was localized or combined with wide-spread pain.     

正畸疼痛的临床研究

疼痛是正畸牙移动过程中的最常见症状之一。许多研究表明疼痛已经成为患者中断正畸治疗最主要的原因之一,随着患者对治疗舒适度要求的增加,如何监测正畸疼痛,如何减轻正畸治疗过程中的疼痛成为正畸医生的研究热点。本文就正畸过程中产生的疼痛特点以及临床上正畸疼痛的控制方法以及研究进展做一综述。     

Genetic contributions to pain: a review of findings in humans

Pain represents the major motivating factor for which individuals seek healthcare, and pain responses are characterized by substantial inter‐individual differences. Increasing evidence suggests that genetic factors contribute significantly to individual differences in responses to both clinical and experimental pain. The purpose of this review article was to summarize the current literature regarding genetic contributions to pain, highlighting findings relevant to oral pain where available. A brief discussion of methodologic considerations is followed by a review of findings regarding genetic influences on clinical pain. Next, the literature examining genetic contributions to experimental pain responses is presented, emphasizing genetic associations that have been replicated in multiple cohorts. It is hoped that an enhanced understanding of genetic contributions to pain responses will ultimately improve diagnosis and treatment of clinical pain conditions.     

Management of postoperative pain in maxillofacial surgery

In this review we describe the evidence base for postoperative analgesia after maxillofacial surgery. We discuss the implications of poorly managed pain, risk factors for the development of severe pain, and pharmacological and non-pharmacological analgesic strategies to manage it.     

Factors associated with pain induced by orthodontic separators

Pain resulting from the application of orthodontic forces varies markedly across individuals. The reasons of this variability are still largely unknown. To investigate factors that may be associated with orthodontic pain following the application of orthodontic separators. One hundred and seven participants were screened for pain response over 48 h following placement of orthodontic elastomeric separators. The highest (n = 10) and lowest (n = 10) pain responders were identified, and data collected on tooth pain sensitivity to electrical stimulation in conjunction with using the Pain Catastrophising Scale (PCS), Dental Anxiety Scale (DAS) and cold pressor test (CPT). There were statistically significant differences between high‐ and low‐pain responders in catastrophising score (P ≤ 0·023). For every PCS magnification score of 1 unit higher, the relative risk of being a high‐pain responder was 1·6 (P = 0·002); those scoring higher on helplessness had a lower risk of being so. DAS scores of high‐pain responders were twice as high as those of low‐pain responder (P = 0·043). During the first 2 min of CPT, the high‐pain responders experienced more pain than the low‐pain responders (P ≤ 0·029). Tooth pain thresholds did not differ between the two different pain responder groups. Pain catastrophising, dental anxiety and cold sensitivity appear to modify the pain experienced following placement of orthodontic separators. Further research is needed to determine the validity of screening questions to identify at‐risk patients prior to commencing orthodontic treatment.     

Widespread pain symptoms and psychological distress in southern Chinese with orofacial pain

Summary  The study investigated the experience of widespread pain (WP) symptoms and psychological distress in southern Chinese with orofacial pain (OFP). A community-based, cross-sectional case–control study involving people aged 35–70 registered with the Hospital Authority/University of Hong Kong Family Medicine Clinic served as the sampling frame. People with recent OFP symptoms and a group without OFP took part. Standard questions were asked about OFP conditions in the previous month. Psychological status was evaluated through depression, and non-specific physical symptoms (NPS) scores were measured with depression and somatization sub-scales of the Symptom Checklist-90. Widespread pain was determined using body outline drawings to identify painful sites prior to a standard clinical examination. Two hundred people with OFP and 200 without OFP participated. Compared with 5·0% in the comparison group ( P  =   0·005), 13·5% of participants with OFP had WP (OFP/WP). Multiple OFP symptoms were more common in the OFP/WP sub-group than the OFP sub-group without WP (OFP/No WP) ( P  <   0·002). Sixty-three percent of the OFP/WP sub-group had moderate/severe depression scores compared with 26·0% in the OFP/No WP sub-group ( P  <   0·001). When pain items were included and excluded, 92·6% and 88·9% of the OFP/WP sub-group had moderate/severe NPS scores, respectively compared with 68·5% and 65·0% in the OFP/No WP sub-group ( P  =   0·004). Co-morbid WP occurred relatively often in southern Chinese with OFP. Psychological distress was common in OFP sufferers, particularly those with WP. A multidisciplinary approach to treatment including cognitive/behavioural therapy should be considered in Chinese people with OFP as part of a WP pattern.     

Factors associated with continuing pain in endodontics

A survey of 100 patients referred to a specialist endodontic practice was undertaken to determine the frequency of various factors associated with continuing pain after endodontic treatment had been commenced by the patient's general dental practitioner. Information was obtained by questioning the patient, examining the tooth, reviewing information supplied by the referring dentist and by observation during subsequent treatment. There were 23 different factors associated with continuing pain — all patients had more than one factor; most (78 per cent) had four, five or six factors; the highest was 9 factors (2 per cent). The most commonly occurring factors were: lack of use of rubber dam (87 per cent), unsatisfactory temporary restorations (80 per cent), and inappropriate use of intracanal medicaments (71 per cent). The other factors were related to diagnostic or treatment errors that could have been avoided in most cases. This survey suggests that dentists need to pay more attention to basic treatment recommendations in order to predictably relieve pain when carrying out emergency endodontics.     

Changing face of orofacial pain: The diagnostic impact of working with Neurology on an orofacial pain clinic

This study assessed the impact of collaborative working with a headache neurologist on diagnoses of patients attending orofacial pain (OFP) clinic. Patient diagnostic data was collected from adult patients attending an Orofacial Pain Service from January 2013 to January 2017. A liaison headache neurologist was appointed late 2015; OFP clinics were co-run with the neurologist specialist thereafter. Overall, 639 patients attended the service; 315 in 2013–2015 and 324 in 2016–2017. Compared to 2013–2015, there were increased rates of diagnoses related to neurovascular (27.5% vs. 19.0%; P = .012) and musculoskeletal pain (36.9% vs. 26.0%; P = .003) in the 2016–2017 cohort and decreased rates of neuropathic (55.6% vs. 70.2%; P < .001) and atypical/idiopathic pain (1.3% vs. 5.4%; P = .003) diagnoses. There was a trend towards an increased rate of comorbid diagnoses (26.3% vs. 20.3%; P = .077), especially those relating to headache conditions. The findings suggest that introduction of a specialist headache neurologist into the OFP clinic widened its remit of assessment, increasing recognition of (co-morbid) neurovascular-related pain and decreasing atypical/idiopathic pain diagnoses in patients with complex OFP. The increase rate of musculoskeletal pain diagnosis in the later cohort is likely attributable to service expansion and normalisation of diagnostics reportedly seen in other OFP services.Statement of clinical relevance: Orofacial pain is a complex diagnosis, it requires a multidisciplinary approach that includes neurological input.     

С��������ʹ����

提要：从胎儿开始,人体感知疼痛的中枢、传导系统和神经末梢就已经形成,并且具备功能。目前,在国内小儿术后疼痛仍被严重忽视,由此给外科手术患儿带来痛苦的同时也影响其康复过程。国外,尤其美国经过2001—2010年“疼痛研究的十年”,投入了大量人力、物力,已经在处理小儿疼痛方面取得喜人的成就。而我国小儿术后疼痛治疗严重滞后,现将国内外有关报道、资料汇总如下。     

The impact of stress and anxiety on the pressure pain threshold of myofascial pain patients

Summary  The purpose of this study was to evaluate the influence of stress and anxiety on the pressure pain threshold (PPT) of masticatory muscles and on the subjective pain report. Forty-five women, students, with mean age of 19·75 years, were divided into two groups: group 1:29 presenting with masticatory myofascial pain (MFP), according to the Research Diagnostic Criteria for Temporomandibular Disorders and group 2: 16 asymptomatic controls. An electronic algometer registered the pain thresholds on four different occasions throughout the academic year. To measure levels of stress, anxiety and pain, the Beck Anxiety Inventory, Lipp Stress Symptoms Inventory and Visual Analog Scale (VAS) were used. Three-way anova and Tukey's tests were used to verify differences in PPT between groups, times and sites. Levels of anxiety and VAS were compared using Mann–Whitney test, while Friedman's test was used for the within-groups comparison at different times (T1 to T4). The chi-squared and Cochran tests were performed to compare groups for the proportion of subjects with stress (α = 0·05). Differences in PPT recordings between time ( P  = 0·001) and sites ( P  < 0·001) were detected. Higher levels of anxiety and lower PPT figures were detected at T2 (academic examination) ( P  = 0·001). There was no difference between groups for anxiety and stress at any time ( P  > 0·05). The MFP group also has shown significant increase of VAS at the time of academic examination ( P  < 0·001). External stressors such as academic examinations have a potential impact on masticatory muscle tenderness, regardless of the presence of a previous condition such as masticatory myofascial pain.