The role of tryptophan and its derivatives in musculoskeletal pains: A systematic review and meta-analysis.

BACKGROUND: Studies present ambiguous findings regarding the role of tryptophan and its metabolites, kynurenine and serotonin in chronic musculoskeletal pain. This systematic review aimed to investigate the expression of tryptophan and its metabolites, serotonin and kynurenine in patients with local and generalized chronic musculoskeletal pain in comparison with pain-free controls. METHODS: An electronic search was conducted in the databases MEDLINE, CINAHL, EMBASE, the Cochrane Central Registry of Controlled Trials (CENTRAL) and Web of Science for clinical and observational trials from the beginning of each database to 21 April 2023. Out of 6734 articles, a total of 17 studies were included; 12 studies were used in the meta-analysis of serotonin, 3 regarding tryptophan and 2 studies for a narrative synthesis regarding kynurenine. Risk of bias was assessed using the quality assessment tool for observational cohort and cross-sectional studies of the National Heart, Lung, and Blood Institute, while the certainty of evidence was by GRADE. RESULTS: All included studies showed a low risk of bias. The meta-analysis showed lower blood levels of tryptophan (p < .001; very low quality of evidence) and higher blood levels of serotonin (p < .001; very low-quality evidence) in patients with generalized musculoskeletal pain, when compared to pain-free individuals. In local chronic musculoskeletal pain, there were higher blood levels of serotonin (p=.251; very low quality of evidence) compared to pain-free individuals. Regarding kynurenine, the studies reported both higher and lower blood levels in generalized chronic musculoskeletal pain compared to pain-free individuals. CONCLUSIONS: The blood levels of tryptophan and its metabolites serotonin and kynurenine seem to influence chronic musculoskeletal pain.

Psychological treatments for temporomandibular disorder pain-A systematic review.

OBJECTIVE: Temporomandibular disorders (TMD) are common. They affect abilities for carrying out daily tasks and influence different psychological aspects. In addition to standard treatment, psychological treatments have been suggested. The aim was to investigate the effects of psychological treatments on patients with painful TMD in a short- and long-term perspective. MATERIALS AND METHODS: An electronic search was conducted in the databases MEDLINE, CINAHL, EMBASE, the Cochrane Central Registry of Controlled Trials (CENTRAL), and Web of Science for randomized clinical trials (RCTs) reporting psychological interventions for TMD. Registered beforehand in PROSPERO (CRD42022320106). In total, 18 RCTs were included; six RCTs that could be used in the meta-analysis, and all 18 RCTs were used in the narrative synthesis. Risk of bias was assessed by the Cochrane's tool for assessing risk of bias and certainty of evidence by GRADE. RESULTS: The narrative synthesis indicates that psychological treatment options seem equivalent to standard treatment for painful TMD. The meta-analysis showed that a combination of psychological treatment and standard treatment and manual treatment (very low-quality evidence) are significantly better in pain reduction than just counselling and standard treatments of TMD. CONCLUSION: This study indicates that psychological treatments seem to reduce pain intensity in individuals with painful TMD, and that the effect seems to be equally good as standard treatment. However, a combination of psychological treatments and standard treatments seems to have an even better effect. This indicates that psychological treatments are promising as an additional treatment approach for painful TMDs.

Are acupuncture and dry needling effective in the management of masticatory muscle pain: A network meta-analysis of randomised clinical trials.

BACKGROUND: Several studies have shown that both acupuncture and dry needling are effective in the treatment of musculoskeletal pains. Therefore, the aim of this network meta-analysis (NMA) was to investigate the treatment outcome of acupuncture and dry-needling for masticatory muscle pain (TMD-M) and to compare with active and inactive placebo. MATERIAL AND METHOD: An electronic search was performed to identify randomised controlled trials (RCTs) published until September 2019, comparing dry-needling, acupuncture, and inactive as well as active placebo in patients with TMD-M. Outcome variables were post-treatment pain intensity, pressure pain threshold (PPT), and maximum mouth opening (MMO). The quality of evidence was rated according to Cochrane's tool for assessing the risk of bias. Mean difference was used to analyse via frequentist NMA using STATA-software. RESULTS: Both NMA and direct pairwise meta-analysis have shown that there was no difference between active treatment with either acupuncture or dry-needling when compared to active and inactive placebo in patients with TMD-M with respect to pain intensity, and PPT (p > .05). However, there was a significant increase in MMO following dry-needling when compared to the placebo (very low-quality evidence). CONCLUSION: Despite the short-term positive effect of MMO by dry-needling, this NMA could not show any pain-reducing effect in patients with TMD-M by acupuncture or dry-needling when compared to an active or inactive placebo. Taken together, this NMA indicates that it is the placebo effect that accounts for the majority of the treatment effect of TMD-M, rather than a real therapeutic effect of acupuncture/dry-needling.

Publication performance and trends in bruxism research: A bibliometric analysis.

BACKGROUND: Bruxism is an umbrella term that encompass a multidimensional spectrum of masticatory muscle activities. OBJECTIVE: The purpose of this study was to do a bibliometric analysis including citation performance in the research topic of bruxism, by using an innovative method including details of article title, author keyword, KeyWords Plus and abstracts. METHODS: The data were retrieved 2022-12-19 from the Clarivate Analytics Web of Science Core Collection, and the online version of the Science Citation Index Expanded (SCI-EXPANDED) for studies published 1992 to 2021. To evaluate research trends, the distribution of keywords in the article title and author-selected keywords were used. RESULTS: The search yielded 3233 documents in SCI-EXPANDED, of which 2598 were of the document-type 'articles' published in 676 journals. The analysis of the articles revealed that "bruxism/sleep bruxism," "electromyography," "temporomandibular disorders" and "masticatory muscles" are the most used keywords by the authors. Further, the most frequently cited study was published 9 years ago and handles the present definition of bruxism. CONCLUSION: The most productive authors and those with the highest performance have some common features; they have several national and international collaborations; and they have published articles about the definition, aetiology/pathophysiology and prevalence of bruxism, all senior researchers in the field of TMD. Hopefully, based on this study, researchers and clinicians will have information to be stimulated to outline future research projects on bruxism-related aspects, and to initiate new international or multinational collaborations.

Are we passing the acceptable? Standard setting of theoretical proficiency tests for foreign-trained dentists.

INTRODUCTION: Dentists educated outside the EU, EEA and Switzerland have the option to undergo proficiency testing to practice dentistry in Sweden. A standardised evidence-based procedure for proficiency tests is crucial. This paper explores if the standard setting of the theoretical examination in the Swedish proficiency test for foreign dentists is fit to differentiate candidates who meet the acceptable standard for licensure from those who do not, by analysis of inter-rater reliability and credibility of Angoff panels and the test's ability to differentiate candidates regarding learning outcomes and dental disciplines. MATERIALS AND METHODS: In a cohort study design, test results were collected from seven examinations during 2018-2019 (n = 316), combined with Angoff judgements and demographic data from The National Board of Health and Welfare. Intraclass correlation, Pearson correlation and linear regression were calculated. RESULTS: All exams demonstrated substantial judge inter-rater reliability using the Angoff procedure (0.65-0.82). Item difficulty predicted by the expert panels showed significant positive correlations with the item difficulty by candidate results (0.69-0.77). Candidates who did not meet the requirements for pass mark in the theoretical test revealed a significantly reduced performance overall in professional qualifications (i.e., learning outcomes) and reduced performance within dental disciplines. CONCLUSIONS: The results indicate that a modified Angoff method is a feasible, simple, and defensible method for setting the pass mark for the theoretical examinations. The standard setting appears to differentiate candidates who do not meet the requirements of the professional qualifications of the dental degree. Adjustments could be undertaken to further discriminate for competence within single dental disciplines.

Early steps towards professional clinical note-taking in a Swedish study programme in dentistry.

BACKGROUND: Higher education tends to focus on academic writing only, instead of emphasizing that professional texts are also used as a basis for communication in contexts with a variety of participators. When it comes to clinical notes, research is scarce and focused on technology and informatics. Therefore, the aim was to explore dental students' clinical notes, and specifically which aspects of the clinical notes characterizes clinical notes that are not sufficient enough for professional purposes. METHODS: The object of analysis was the student's written completion of a teacher constructed protocol regarding oral mucosa, the dental apparatus including pathology on tooth level, oral hygiene, and a validated international clinical examination protocol of the temporomandibular region. The study was framed within the New Literacy Studies approach, and the clinical notes were analyzed using thematic analysis. RESULTS: Within the clinical notes three themes were identified; a) familiar content; b) familiar content in new context; and c) new content. The forms of notes could refer to either categorizational clinical notes or descriptive clinical notes. Most students were able to write acceptable clinical notes when the content was familiar, but as soon as the familiar content was in a new context the students had difficulties to write acceptable notes. When it comes to descriptive notes students suffered difficulties to write acceptable notes both when it came to familiar content, or familiar content in a new context. CONCLUSIONS: Taken together, the results indicate that students have difficulties writing acceptable notes when they are novices to the content or context, making their notes either insufficient, too short or even wrong for professional purposes. With this in mind, this study suggests that there is a need to strengthen the demands on sufficient professional quality in clinical notes and focus on clinical notes already in the early stages of the different medical educations.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis-Symptoms, clinical signs and radiographic findings.

BACKGROUND: Although many children with juvenile idiopathic arthritis (JIA) develop arthritis and deformity of the temporomandibular joint (TMJ), many go undetected. OBJECTIVE: This study investigates whether findings from patient history and clinical examination using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) can be used to diagnose TMJ involvement. METHODS: As a part of the screening program, 59 consecutive JIA patients age 7-14 years underwent a clinical examination according to RDC/TMD including self-reported orofacial pain and pain related to jaw function, and cone beam computer tomography (CBCT). Data were obtained from the patient's medical charts. Patients were divided into two groups based on the presence or absence of TMJ deformities on CBCT. RESULTS: Self-reported TMJ symptoms before inclusion were reported by 52% of children with and 18% of children without TMJ deformities on CBCT (p = .020). On a group level, the maximum unassisted (mouth) opening (MUO) with and without pain was within the normal range, but children with TMJ deformities showed a significantly smaller MUO with pain (p = .035). A diagnosis of osteoarthritis and osteoarthrosis was more prevalent in children with TMJ deformities. CONCLUSION: Although there were few differences between children with and without radiographic TMJ deformities, self-reported previous TMJ symptoms and reduced MUO with pain could indicate the presence of TMJ involvement. However, radiographic examinations are needed to confirm TMJ involvement. Thus, this study indicates that the RDC/TMD protocol is a blunt tool when targeting TMJ involvement in JIA.

Bone Graft Osseous Changes After Maxillary Sinus Floor Augmentation: A Systematic Review.

This systematic review aimed to evaluate computed tomographic scans for volumetric bone gain following lateral sinus floor augmentation of the atrophic posterior maxilla after the use of various bone-grafting materials. The databases MEDLINE, EMBASE, CINAHL, Cochrane Central Registry of Controlled Trials (CENTRAL), and SCOPUS were used for a comprehensive search for all potentially eligible randomized controlled trials (RCTs), without language restrictions, from the beginning of each database until June 2021. The predictor variables for this review were autogenous bone (AB), allografts (AG), xenografts (XG), and alloplastic bone (AP), which were assessed individually and in combination with the inclusion of growth factors with XGs. The outcome variable was the graft volume on cone beam computerized tomographic (CBCT) scans. Seven RCTs with a short-term observation period were included. Topographical analyses of all graft materials identified a volumetric reduction at 6 months postgrafting, compared with values immediately after graft placement. The volumetric reduction occurred regardless of the type of bone-grafting material. The largest volumetric gain over baseline, pregraft values, was found in the AG+XG group. Autografts, the present gold standard bone graft, showed a high resorption rate and inferior volumetric increase when compared with alternative grafting combinations. AG and XG also showed a significant difference with less volumetric gain than AP and their combinations. No difference was detected between AP and AG+AP. However, there was significantly less volumetric gain for AP alone compared with AG+XG and XG-growth factor combinations. As a result, these findings suggest significant advantages to new bone formation using grafting materials in combination. To achieve a better understanding of topographical variables related to various grafting materials, more clinically focused RCTs, with sufficient statistical power to control for confounding factors, are needed.

Literacy as part of professional knowing in a Swedish dental education.

BACKGROUND: Academic reading and writing are seen as self-evident literacy competences in most contemporary higher educations, however, whether students also are introduced to professional literacy of relevance for dentistry during their education is a question. The purpose of this study is to analyze one of the Swedish dental programmes, with respect to its design, in relation to possible content of relevance for academic and professional literacy. Secondarily, to identify and analyze Swedish dental students' writing in an academic setting, i.e. what these students are expected to read and write, and how they write. METHODS: Data, for this ethnographically inspired case-study, was produced by observations and audio-recordings of lectures, copies of teachers' handouts and of volunteering students' notes, and a multiple-choice-test. Data-analysis was made in five steps, starting with macro-level data, i.e. curriculum and syllabuses, followed by the syllabuses for the two observed modules, the teacher-provided material, analysis of the students' notes, while in the fifth and final step, the results from the previous steps were compared, to find patterns of what students were expected to read and write, and what in the teacher-provided multimodal material that was emphasized in teachers' talk. RESULTS: This study showed that students were engaged in several types of literacy events, such as reading, finding and watching videos on their learning platform, writing, and following instructions. The study also showed that there is a recurrent academic content comprised of anatomy, physiology and pathology, while the professional content comprised of patient communication and anamnesis. Further, an integrated content was found and was initiated in teacher-constructed PowerPoints and by student-questions. Note-taking patterns varied between individual students, but the general pattern for this group of students were the use of complementary notes. This type of note-taking was used to make available further descriptions of the teacher-constructed text in PowerPoints, but also an independent text describing pictures shown on teachers' PowerPoints or the blackboard. CONCLUSION: Findings from the present study reveal that students either copy text from teachers' PowerPoint-slides, re-formulate text from teachers' PowerPoint-slides, or write complementing text to teachers' PowerPoint-slides. Further, the students individually choses type of note-taking based on situation. The study also revealed that the academic literacy - in the two modules during the fifth and sixth semesters of a dental education analyzed - mainly has a professional basis for reading, writing, and communication purposes. The study also showed that academic and professional literacy are closely connected through recurrent integration.

Sterile water; a novel and promising human experimental craniofacial muscle pain model.

BACKGROUND: The aim of this study was to investigate if intramuscular injection of sterile water can be used as a human experimental pain model that resembles clinical craniofacial muscle pain and to analyse if the effects differ between sexes. METHODS: This randomised, double-blind, placebo-controlled cross-over study included 30 healthy age-matched women and men (23.6 ± 2.4 years). At three sessions, with at least one week of washout in between, 0.2 mL of either sterile water (test-substance), hypertonic saline (58.5 mg/mL; active control) or isotonic saline (0.9 mg/mL; passive control) was randomly injected into the right masseter muscle. Pain intensity (VAS) was continuously assessed during 5 min whereafter pain duration (s) and pain area (au) were calculated; pressure pain thresholds (PPT;kPa) were recorded every 5 minutes during 30 minutes. RESULTS: Sterile water evoked pain of similar intensity (74.5 ± 49.9) as hypertonic saline (74.0 ± 50.5); whereas, isotonic saline evoked low-intensity pain (11.4 ± 23.4). The pain induced by sterile water and hypertonic saline had higher intensity (P < 0.001), longer duration (P < 0.001) and larger pain area (P < 0.001) than isotonic saline. There were no significant differences in any pain variable between sterile water and hypertonic saline. The PPT did not change significantly after any substance, except for in women 5 minutes after sterile water injection (P < 0.002). Pain duration was longer in the men for all substances (P < 0.006), while the pain area was larger in women after injection of hypertonic saline (P < 0.003). CONCLUSION: These results indicate that pain evoked by sterile water resembles clinical muscle pain and may offer a novel and simpler alternative to hypertonic saline injections.

Density of nerve fibres and expression of substance P, NR2B-receptors and nerve growth factor in healthy human masseter muscle: An immunohistochemical study.

BACKGROUND: In skeletal muscle, free nerve endings are mostly located within the connective tissue. However, the distribution of sensory afferent fibres in healthy human masseter muscle tissues has not been studied. OBJECTIVES: Primarily to investigate human masseter muscle nerve fibre densities as well as expression of NR2B receptors, substance P (SP) and nerve growth factor (NGF), and secondarily to compare this between a) nerve fibres associated with myocytes and within connective tissue; b) sexes; and c) ages. METHODS: Microbiopsies of the masseter muscle were obtained from 60 sex- and age-matched healthy participants. Biopsy sections were analysed using immunohistochemistry and were visualised with a Leica TCS SPE confocal microscope. The Mann-Whitney U test was used for statistical analyses. RESULTS: The density of nerve fibres within connective tissue was significantly greater than in nerve fibres associated with myocytes (P < .001). Nerve fibres within connective tissue expressed SP alone or together with NR2B significantly more often than those associated with myocytes (P < .001). The frequency of nerve fibres, which expressed SP alone or in combination with NR2B or NGF, was significantly greater in women than in men (P < .050). Moreover, the co-expression of the three markers together was inversely correlated with age in women (P < .002). CONCLUSIONS: There is a higher density and greater expression of sensory nerve fibres within the connective tissue than associated with myocytes in healthy human masseter muscle. This suggests that nerve fibres within connective tissue are more involved in nociception than nerve fibres associated with myocytes.

Is the therapeutic effect of occlusal stabilization appliances more than just placebo effect in the management of painful temporomandibular disorders? A network meta-analysis of randomized clinical trials.

STATEMENT OF PROBLEM: Occlusal devices, particularly the stabilization appliances, have been commonly used as treatment for painful temporomandibular disorders (TMDs). However, the mechanisms of action of these devices are still unclear, including the role of the placebo effect in the pain management. PURPOSE: The purpose of this network meta-analysis was to identify to what extent the degree of efficacy of stabilization appliances in the management of painful TMDs arises from the placebo effect only or whether it arises chiefly from an actual effect. MATERIAL AND METHODS: An electronic search was undertaken to identify randomized clinical trials (RCTs) published up to April 2020, comparing the efficacy of the stabilization appliances in patients with painful temporomandibular disorders, with nonoccluding appliances (active placebo), and untreated controls (passive placebo). Outcome variables were pain intensity at follow-ups, the proportion of participants reporting pain improvement, and the number needed to treat. The quality of evidence was rated as per the Cochrane tool for assessing risk of bias. Mean difference was used to analyze via frequentist network meta-analysis by using the STATA software program. RESULTS: Treatment with stabilization appliances showed a significant reduction in pain intensity when compared with the other groups; but, the lower pain intensity at follow-ups in favor of stabilization appliances when compared with nonoccluding appliances was not statistically significant. However, a significantly higher number of participants reported pain improvement after treatment with stabilization appliances when compared with those treated with nonoccluding appliances or untreated participants. CONCLUSIONS: This network meta-analysis showed no significant difference in reported pain intensity at follow-ups between the treatment of painful TMDs with stabilization appliances or nonoccluding appliances (active placebo). However, a significant difference in participants reporting treatment satisfaction with reduced pain, and a significantly lower number needed to treat in favor of stabilization appliances were found. Patient-reported treatment satisfaction probably included more domains than just pain intensity, such as improvements in physical functioning and psychosocial factors, and deserves further investigation. The authors concluded that stabilization appliances treatment efficacy is beyond the placebo effect.

Experimental muscle pain and music, do they interact?

BACKGROUND: Music is used to evoke audio analgesia during dental procedures, but it is unknown if experimental pain and music interact. This study aimed to explore the multisensory interaction between contrasting types of music and experimentally induced muscle pain. METHODS: In 20 healthy women, 0.3 mL sterile hypertonic saline (5.8%) was injected into the masseter muscle during three sessions while contrasting music (classical and black metal) or no music was played in the background. Pain intensity was assessed every 15 seconds with a 0-100 mm visual analogue scale (VAS) until pain subsided. Pain spread (pain drawings), unpleasantness (VAS), anxiety (VAS), and pain quality (McGill Questionnaire) were assessed after the last pain assessment. RESULTS: Pain of high intensity was evoked at all sessions with a median (interquartile range) peak pain intensity of 78 (30) in the black metal music, 86 (39) in the classical music, and 77 (30) in the control session. The pain duration was 142 (150) seconds in the black metal music, 135 (150) seconds in the classical music, and 135 (172) seconds in the control session. The corresponding pain-drawing areas were 42 (52), 37 (36), and 44 (34), arbitrary units respectively. There were no differences in any of these variables (Friedman's test; P´s > .368), or in unpleasantness, anxiety, or pain quality between sessions (P´s > .095). CONCLUSIONS: Experimentally induced muscle pain does not seem to be influenced by contrasting types of background music. Further studies exploring the multisensory integration between music and experimental muscle pain are needed.

Characteristics of dental note taking: a material based themed analysis of Swedish dental students.

BACKGROUND: The transition from upper secondary to higher education and from higher education to professional practice requires that students adapt to new literacy practices, academic and professional. However, there is a gap of knowledge regarding literacy practices in dental education. Therefore, the aim of this study was to identify what characterizes dental students' notetaking and secondarily to determine what dental students express regarding their notetaking. METHODS: To analyze students' perspectives about the purposes of notetaking and to examine their written notes in depth, three volunteer students, out of the 24 students that voluntarily and anonymously handed in their notes, were interviewed. The three undergraduate dental students that participated in this material-based, semi-structured interview study, framed within a New Literacy Studies approach, were on their third year (6th semester). The focus of these material-based interviews was on each student's notes. Questions prepared for semi-structured interviews were open-ended and allowed for individual follow-up questions related to the interviewee's answer. To analyze the outcome of the interviews a thematic analysis was used. RESULTS: From the material-based interviews eight themes that relate to what, how and for what purpose students write were discerned. These eight themes include professional vocabulary, core content as well as clinical examples that belong to what students read and write; multimodal accentuation as well as synthesis that belong to how students read and write; and mnemonic strategies, academic purposes, and professional purposes that belong to for what purpose students read and write. CONCLUSIONS: Findings from the interviews indicate that the digital development, offering a variety of available tools, has expanded the notion of notetaking. This study identified that dental students' notetaking has changed during their education from initially being synchronous, to also include multimodal and asynchronous writing, making notetaking more of a writing practice. Further, students' writing practices seem to be motivated by their knowledge formation in relation to a subject matter, but also in relation to their experiences during clinical training. Although, our hypothesis was that the main purpose of notetaking and writing was to pass their course examinations, this study showed that students that were half-way through their dental education, are aware that literacy practices are for learning for their future profession, and not only for passing their exams.

Needling therapies in the management of myofascial pain of the masticatory muscles: A network meta-analysis of randomised clinical trials.

OBJECTIVE: A network meta-analysis (NMA) of randomised clinical trials (RCTs) was performed aiming to compare the treatment outcome of dry needling, acupuncture or wet needling using different substances in managing myofascial pain of the masticatory muscles (TMD-M). METHOD: An electronic search was undertaken to identify RCTs published until September 2019, comparing dry needling, acupuncture or wet needling using local anaesthesia (LA), botulinum toxin-A (BTX-A), granisetron, platelet-rich plasma (PRP) or passive placebo versus real active placebo in patients with TMD-M. RCTs meeting the inclusion criteria were stratified according to the follow-up time: immediate post-treatment to 3 weeks, and 1 to 6 months post-treatment. Outcome variables were post-treatment pain intensity, increased mouth opening (MMO) and pressure threshold pain (PPT). The quality of evidence was rated according to Cochrane's tool for assessing risk of bias. Mean difference (MD) was used to analysed via frequentist NMA using Stata software. RESULTS: Twenty-one RCTs involving 959 patients were included. The quality of evidence of the included studies was low or very low. There was significant pain decrease after PRP when compared to an active/passive placebo and acupuncture. There was a significant improvement of MMO after LA (MD = 3.65; CI: 1.18-6.1) and dry needling therapy (MD = 2.37; CI: 0.66-4) versus placebo. The three highest ranked treatments for short-term post-treatment pain reduction in TMD-M (1-20 days) were PRP (95.8%), followed by LA (62.5%) and dry needling (57.1%), whereas the three highest ranked treatments at intermediate-term follow-up (1-6 months) were LA (90.2%), dry needling (66.1%) and BTX-A (52.1%) (all very low-quality evidence). LA (96.4%) was the most effective treatment regarding the increase in MMO followed by dry needling (72.4%). CONCLUSION: Based on this NMA, one can conclude that the effectiveness of needling therapy did not depend on needling type (dry or wet) or needling substance. The outcome of this NMA suggests that LA, BTX-A, granisetron and PRP hold some promise as injection therapies, but no definite conclusions can be drawn due to the low quality of evidence of the included studies. This NMA did not provide enough support for any of the needling therapies for TMD-M.

Experimental pain and fatigue induced by excessive chewing.

BACKGROUND: The study was aiming to optimize excessive gum chewing as an experimental model to induce jaw muscle pain and fatigue similar to those in painful TMDs with durations that would allow immediate investigations of jaw-motor function. Further, if any sex differences would be detected in the expression of pain. METHODS: This randomized, double blinded study included 31 healthy participants of both sexes. A standardized chewing protocol of either 40- or 60-min of chewing was used with a wash-out period of 1 week. Subjective fatigue, pain characteristics and functional measures were assessed. For statistical analyses, Wilcoxon Signed Rank test, Mann-Whitney Rank Sum test and Friedman's ANOVA with Tukey post-hoc test were used. RESULTS: High subjective fatigue scores that lasted up to 20 min after the end of the trial were significantly induced both in the 40- and 60-min chewing trials (P <  0.001*). Significant but mild pain was induced only in the 60-min trial (P = 0.004*) and only in men (P = 0.04*). Also, the induced pain area was significantly bigger in the 60-min trial (P = 0.009*). However, this increase in pain and pain area did not last to the first 10-min follow-up. There were no significant differences neither between the 40- and 60-min chewing trials, except regarding the pain area (P = 0.008*), nor between the sexes. CONCLUSION: Taken together, excessive chewing in its current form does not seem to be a proper pain experimental model. The model needs further adjustments in order to mimic TMD-pain especially in women and to prolong the pain duration.

Prevalence and treatment strategies regarding temporomandibular disorders in children and adolescents-A systematic review.

AIMS: Temporomandibular disorders (TMD) in children/adolescents are very common. Yet, there is a lack of consensus regarding which clinical interventions are appropriate. The aim of this systematic review was to gather and assess the quality of the available literature on the prevalence and evidence-based treatment strategies in children and adolescents suffering from TMD. METHODS: A systematic literature review was conducted including articles from 1992 to 2016. A total of 2293 articles were found. Eight were included, six regarding prevalence and two regarding treatment. Simple or multiple conjunctions of different search words: "temporomandibular disorder", "temporomandibular joint disorder", "prevalence", "children" "adolescents", "occlusal appliance", "jaw exercise" and "relaxation" were used on the databases PubMed and Web of Science. Inclusion criteria were (a) scientific articles or randomised controlled clinical trials evaluating prevalence, choice of therapy and treatment outcome for children and/or adolescents with TMD published in Swedish or English and (b) a TMD diagnosis according to the Research Diagnostic Criteria for TMD or Diagnostic Criteria for TMD. RESULTS: Prevalence (ages 10-19 years) varied between 7.3 and 30.4%, and the most common diagnoses were myofascial pain and anterior disc displacement with reduction. Only two articles were found regarding treatment in adolescents (ages 12-18 years). The stabilising occlusal appliance had superior treatment outcome compared to relaxation therapy or brief information. CONCLUSION: The general absence of standardised studies concerning children/adolescents with TMD pain states the evident need for further systematic prevalence and treatment evaluations. Considering this, it is not possible to achieve any evidence-based treatment strategies or guidelines for children and adolescents with TMD.

Using the child behavior checklist to determine associations between psychosocial aspects and TMD-related pain in children and adolescents.

BACKGROUND: Since children and adolescents are frequently experiencing emotional and behavioral consequences due to pain, their parents should be aware of this emotional and behavioral status. Therefore, the aim of this study was to analyze and describe the parents' reports of the emotional and behavioral status of children and adolescents with different types of temporomandibular disorders using the Child Behavior Checklist. METHODS: This Cross-sectional study comprises of 386 randomly selected children and adolescents that ages between 10 and 18 years in Jeddah. One day prior the clinical examination according to Research Diagnostic Criteria for temporomandibular disorders (TMD) Axis I and II, Arabic version of the Child Behavior Checklist scale was distributed to the parents of participant. According to the diagnosis, the participants were divided into three groups; non-TMD group, TMD-pain group, and TMD-painfree group. RESULTS: In regard to internalizing problems, the parents to the children and adolescents in the TMD-pain group rated a higher frequency of anxiety, depression and somatic complaints in their children than the parents of children in the non-TMD group (p < 0.05). Only one significant association regarding the externalizing problems was found for the aggressive behavior in the TMD-pain group. CONCLUSION: The parents rated that their children with TMD-pain suffer from emotional, somatic and aggressive behavior to a higher degree than healthy control subjects. Also, the parents believed that TMD-pain influenced their children's physical activities but not social activities.

Effects of audiovisual distraction on children's behaviour during dental treatment: a randomized controlled clinical trial.

AIM: Dental anxiety leads to undesirable distresses such as avoidance of dental treatment and increase stress among caregivers that consequently affect the treatment quality. The aim of this study was therefore to evaluate the effectiveness of viewing videotaped cartoons using an eyeglass system (i-theatre™) as an audiovisual (AV) distraction technique on behaviour and anxiety in children receiving dental restorative treatment. METHODS: Fifty-six consecutive children patients who presented for treatment and met inclusion criteria were included and randomly divided into two groups; a control group without distraction (CTR-group) and a distraction-group (AV-group). Three dental treatment visits were provided for each patient. Anxiety and cooperative behaviour were assessed with the Facial Image Scale (FIS) and the Modified Venham's clinical ratings of anxiety and cooperative behaviour scale (MVARS). The vital signs, blood pressure and pulse were also taken. RESULTS: The AV-group showed significantly lower MVARS scores than the CTR-group (p = 0.029), and the scores decreased significantly during treatment in the AV-group (p = 0.04). Further, the pulse rate was significantly increased in the CTR-group during injection with local anaesthesia (p = 0.02), but not in the AV-group. CONCLUSION: AV distraction seems to be an effective method in reducing fear and anxiety in children during dental treatment. Further, children who used eyeglass goggle display as a distraction tool during dental treatment reported not only less anxiety than control groups but also showed more positive responses after injection with local anaesthesia. Hence, AV-distraction seems to be a useful tool to decrease the distress and dental anxiety during dental treatment.

The associations between psychosocial aspects and TMD-pain related aspects in children and adolescents.

BACKGROUND: Temporomandibular disorders (TMD) in children and adolescents is prevalent with pain as a common component, and has a comorbidity with psychosocial problems such as stress, depression, anxiety as well as somatic complaints. Therefore, the aim of the study was to investigate if psychosocial problems in children and adolescents are associated with TMD with pain (TMD-pain) and TMD without pain (TMD-painfree) when compared to children and adolescents without TMD. METHODS: This cross-sectional study consisted of 456 randomly selected children and adolescents, enrolled from 10 boy's- and 10 girl's- schools in Jeddah, between 10 and 18 years of age. On the examination day, prior to the clinical examination according to Research Diagnostic Criteria for TMD Axis I and II, the participants first answered two validated questions about TMD pain, and after that the Arabic version of the Youth Self Report scale. According to their clinical examination and diagnosis the participants were divided into three groups; non-TMD group, TMD-pain group, and TMD-painfree group. RESULTS: The TMD-pain group presents a higher frequency of the internalizing problems anxiety, depression and somatic complaints than non-TMD group (p < 0.05). Regarding externalizing problems the only significant association found was for aggressive behavior in the TMD-pain group (p < 0.05). The TMD-pain group also shows a higher frequency of social problems than the non-TMD group. However, no such difference was found when compared to the TMD-painfree group. There was also a significant association with a higher frequency of thought problems in the TMD-pain group (p < 0.05). The children's and adolescents' physical activities were within border line clinical range for all three groups, whereas the social competence was within the normal range. There were no significant associations between any of the groups in this respect. CONCLUSIONS: TMD-pain in children and adolescents does not seem to affect the social activities. However, TMD-pain seem to have a strong association to emotional, behavior and somatic functioning, with higher frequencies of anxiety, depression, somatic problems, aggressive behavior and thought problems, than children and adolescents without TMD-pain. With respect to the biopsychosocial model the present study indicates that there are significant associations to psychosocial, somatic and behavioral comorbidities and TMD-pain in children and adolescents in the Middle East region.