Generalized joint hypermobility and temporomandibular disorders: inherited connective tissue disease as a model with maximum expression

AIMS: To study the relationship between generalized joint hypermobility (GJH) and temporomandibular disorders (TMD) by assessing prevalence and patient characteristics of TMD in a population of patients with maximum expression of GJH as a symptom of inherited connective tissue disease. In addition, diagnostic reliability of a series of clinical signs indicative of temporomandibular joint (TMJ) hypermobility was tested. METHODS: The study sample consisted of 42 subjects with GJH, 24 with Marfan syndrome and 18 with Ehlers-Danlos syndrome. A subgroup of 27 individuals was selected by age (> or = 18 yrs) and was compared to 40 controls with TMD and normal peripheral joint mobility. TMD diagnoses were assigned to each subject according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). RESULTS: In the GJH sample (n = 42), 71.4% of the subjects were symptomatic for TMD. Of those, 13.3% had sought treatment. A myofascial pain diagnosis was made in 69%, disc dislocation with reduction was diagnosed in 85.7%, and TMJ arthralgia in 61.9%. Multiple TMD diagnoses were assigned in 69% of the subjects; of these, 57% had 3 or more subgroup diagnoses. Joint noises (P < .01) and recurrent TMJ dislocations (P < .01) were a frequent finding in adult GJH subjects (n = 27) compared to controls, with symptomatic GJH subjects presenting more and more prolonged dislocation events than asymptomatic subjects (P < .001). TMJ hypermobility signs were expressed significantly more often in GJH compared to controls with TMD and normal joint mobility. CONCLUSION: This study indicates a positive relationship between GJH and TMD.     

Association between generalized joint hypermobility and signs and diagnoses of temporomandibular disorders

The aim of this study was to analyze whether generalized joint hypermobility (GJH) is a risk factor for temporomandibular disorders (TMD). We examined 895 subjects (20–60 yr of age) in a population‐based cross‐sectional sample in Germany for GJH according to the Beighton classification and for TMD according to the Research Diagnostic Criteria for TMD (RDC/TMD). After controlling for the effects of age, gender, and general joint diseases using multiple logistic regression analyses, hypermobile subjects (with four or more hypermobile joints on the 0–9 scale) had a higher risk for reproducible reciprocal clicking as an indicator for disk displacement with reduction (Odds Ratio (OR) = 1.68) compared with those subjects without hypermobile joints. Concurrently, subjects with four or more hypermobile joints had a lower risk for limited mouth opening (< 35 mm; OR = 0.26). The associations between GJH and reproducible reciprocal clicking or limited mouth opening were statistically significant in a trend test. No association was observed between hypermobility and myalgia/arthralgia (RDC/TMD Group I/IIIa). In conclusion, GJH was found to be associated with non‐painful subtypes of TMD.     

Clinical evaluation of the temporomandibular joint following orthognathic surgery--multiple logistic regression analysis

This study compares temporomandibular joint dysfunction (TMD) symptoms before and after bilateral sagittal split ramus osteotomy, and identifies predictive factors for the postoperative TMD symptoms by assessing the adjusted odds ratio using multiple logistic regression analysis. A consecutive series of 37 cases treated only with bilateral sagittal split ramus osteotomy were evaluated. New postoperative TMD symptoms appeared in 9 cases, preoperative TMD symptoms disappeared in 6 cases, and TMD symptoms were unchanged in 5 cases. The median period until the interincisal opening range attained 40 mm was 5 months (range, from 2 to 15 months). Age was a positive factor in patients with postoperative TMD symptoms, with an odds ratio of 1.43 (95 percent confidence interval, from 1.05 to 1.93). In addition, the maximum value of the bilateral setback distance of more than 9 mm was a positive factor of 6.95 (95 percent confidence interval, from 1.06 to 45.42). We concluded that surgical correction in skeletal malocclusion may affect temporomandibular joint dysfunction symptoms.     

Hypermobility and trauma as etiologic factors in patients with disc derangements of the temporomandibular joint

The aim of the study was to investigate patients with temporomandibular joint (TMJ) disc derangement with its two clinical variants reciprocal clicking (RC) and chronic closed lock (CCL) with regard to the etiologic factors, previous jaw trauma and general (GJH) and local joint hypermobility (LJH). 42 patients (21 with RC and 21 with CCL) and 20 control individuals were studied. The patients and controls were asked whether they had sustained any jaw trauma in the past and were then examined for the presence of GJH and LJH, using defined criteria. Patient and control groups were compared. Statistical evaluation included χ(2) test and paired Student's t test. Odds ratio was calculated in order to assess the relative risk of developing RC and CCL when the etiological factor was present. The results showed a significant association between RC and GJH (OR=9.6, p=0.0010) as well as LJH (OR=38, p=0.0001). CCL was clearly associated with GJH (OR=7.5, p=0.0030) while its association with LJH was not significant (OR=9.5, p=0.0582). No significant association with previous trauma was found. The results indicate that GJH is an important etiologic factor for the development of RC and CCL of the TMJ.     

‘I was cracking more than everyone else’: young adults' daily life experiences of hypermobility and jaw disorders

Most studies on general joint hypermobility (GJH) and temporomandibular disorders (TMD) are quantitative and have concluded that joint hypermobility is a risk factor for development of TMD. The present qualitative study aimed to explore young adults' daily life experiences of GJH, specifically these relating to jaw function, and their experiences of medical and dental care providers. Semi-structured interviews were conducted with nine young adults (18–22 yr of age) and data were analysed using qualitative content analysis. The overarching thematic category that emerged was ‘Hypermobility in daily life’, which was broken into six subthemes and three themes: ‘emotional perception’, ‘dealing with symptoms’, and ‘outside influences’. Participants' narratives centred on experiences of complex symptoms, awkward jaw function and joint noises, feeling different, and a lack of support from general medical and dental care providers. The findings show that young adults with joint hypermobility need early support from medical and dental care providers for managing their symptoms and conditions related to GJH. Future studies are warranted to develop guidelines for professionals in medical and dental care to detect and prevent forthcoming problems and to offer relevant support to hypermobile youths.     

Incisal tooth wear and self-reported TMD pain in children and adolescents

PURPOSE: Incisal tooth wear may be a sign of long-term bruxing behavior. Bruxism is purported to be a risk factor for temporomandibular disorders (TMD). The aim of this population-based cross-sectional study was to determine if anterior tooth wear is associated with the self-report of TMD pain in children and adolescents. MATERIALS AND METHODS: In a population sample of 1,011 children and adolescents (mean age 13.1 years, range 10 to 18 years; female 52%; response rate 85%), TMD cases were defined as subjects reporting pain in the face, jaw muscles, and temporomandibular joint during the last month according to RDC/TMD. All other subjects were considered controls. Incisal tooth wear was assessed in the clinical examination using a 0 to 2 scale (no wear, enamel wear, dentin wear) for every anterior permanent tooth. The mean wear score for the individuals was categorized into 0, 0.01 to 0.20, 0.21 to 0.40, and 0.41+. A multiple logistic regression analysis, controlling for the effects of age and gender, analyzed the association between the categorized summary wear score and TMD. Specifically, the hypothesis of a trend between higher tooth wear scores and higher risk of TMD was tested. RESULTS: An odds ratio of 1.1 indicated, after adjusting for gender and age, no statistically significantly higher risk of TMD pain with higher tooth wear scores. CONCLUSION: Incisal tooth wear was not associated with self-reported TMD pain in 10- to 18-year-old subjects.     

Is there a higher prevalence of tinnitus in patients with temporomandibular disorders? A systematic review and meta‐analysis

The aim of this study was to determine whether there exists a higher prevalence of tinnitus in patients with temporomandibular disorders (TMDs) than in patients without TMDs. A systematic review was conducted in PubMed/MEDLINE for articles published between January 1992 and April 2018 in accordance with the PRISMA statement. Studies were included in this review only if they assessed TMDs using the research diagnostic criteria (RDC)/TMD or DC/TMD. A total of five studies were included in the systematic review, and a random‐effects meta‐analysis of three of the studies was conducted. In all of the selected studies, the prevalence of tinnitus was higher in patients with TMDs (35.8% to 60.7%) than in patients without TMDs (9.7% to 26.0%). The odds ratio of suffering from tinnitus among patients with TMDs was 4.45 (95% CI 1.64‐12.11. P = 0.003). Thus, despite the limitations of the included studies, this review demonstrates that the prevalence of tinnitus in TMD patients is significantly higher than that in patients without TMD.     

Prevalence of different temporomandibular joint sounds,with emphasis on disc-displacement,in patients with temporomandibular disorders and controls

Temporomandibular joint (TMJ) sounds are very common among patients with temporomandibular disorders (TMD), but also in non-patient populations. A variety of different causes to TMJ-sounds have been suggested e.g. arthrotic changes in the TMJs, anatomical variations, muscular incoordination and disc displacement. In the present investigation, the prevalence and type of different joint sounds were registered in 125 consecutive patients with suspected TMD and in 125 matched controls. Some kind of joint sound was recorded in 56% of the TMD patients and in 36% of the controls. The awareness of joint sounds was higher among TMD patients as compared to controls (88% and 60% respectively). The most common sound recorded in both groups was reciprocal clickings indicative of a disc displacement, while not one single case fulfilling the criteria for clicking due to a muscular incoordination was found. In the TMD group women with disc displacement reported sleeping on the stomach significantly more often than women without disc displacement did. An increased general joint laxity was found in 39% of the TMD patients with disc displacement, while this was found in only 9% of the patients with disc displacement in the control group. To conclude, disc displacement is probably the most common cause to TMJ sounds, while the existence of TMJ sounds due to a muscular incoordination can be questioned. Furthermore, sleeping on the stomach might be associated with disc displacement, while general joint laxity is probably not a causative factor, but a seeking care factor in patients with disc displacement.     

Relationship between overbite/overjet and clicking or crepitus of the temporomandibular joint

AIMS: Since occlusal variables such as overbite and overjet have been thought to be associated with temporomandibular disorders (TMD), and joint sounds are some of the most prevalent signs of TMD, the aim of this study was to determine whether overbite and overjet are risk factors for temporomandibular joint (TMJ) sounds. METHODS: A population-based cross-sectional study of 3,033 subjects (age range, 10 to 75 years; 53% female) was conducted in Germany. Overbite/overjet, reproducible reciprocal clicking (RRC) during open-close jaw movements that did not occur in the protrusive jaw position, and joint crepitus were assessed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). RESULTS: When age and gender were controlled for, high or low values of overbite and overjet were not associated with a greater risk of RRC and crepitus as compared to a reference category of a normal overbite and overjet of 2 to 3 mm (multiple logistic regression; odds ratios 0.7 to 1.3; P > .05 for all). CONCLUSION: This study showed that higher or lower overbite or overjet jaw relationships, even extreme values, are not risk factors for TMJ sounds as assessed by clinical examination.     

The association of temporomandibular disorder pain with history of head and neck injury in adolescents

AIMS: To evaluate the risk of self-reported temporomandibular disorder (TMD) pain among adolescents in relation to previous head and/or neck injury. METHODS: 3,101 enrollees (11 to 17 years of age) of a nonprofit integrated health-care system were interviewed by telephone. Two hundred four cases with self-reported TMD pain and 194 controls without self-reported TMD pain frequency-matched to the cases by age and gender completed standardized in-person interviews and physical examinations in which reports of previous head/neck injuries were recorded. Odds ratio (OR) estimates and 95% confidence intervals (CIs) of the relative risks of TMD pain associated with prior head and/or neck injuries were calculated using logistic regression. RESULTS: A greater proportion of subjects reporting TMD pain (36%) than controls (25%) had a history of head and/or neck injuries (OR = 1.8, 95% CI, 1.1-2.8). In a separate analysis, the presence of TMD based upon the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) was assessed in relation to prior head and/or neck injury. Cases reporting TMD pain and meeting the RDC/TMD criteria for myofascial pain and/or arthralgia or arthritis were 2.0 (CI, 1.0-3.8) times more likely to have had a prior head injury than were controls with neither self-reported nor RDC/TMD pain diagnoses. CONCLUSION: The results suggest a modest association of prior head injuries with both self-reported and clinically diagnosed TMD pain in adolescents.     

Temporomandibular disorders in 19-year-old Korean men.

PURPOSE: The purpose of this study was to determine the prevalence and the nature of the relationships between 3 temporomandibular joint disease (TMD) symptoms and symptoms of associated structures. MATERIALS AND METHODS: This study was designed to rule out the effect from the uneven composition of the samples on TMD symptoms. The samples were collected from subjects who were of the same age, gender, district, and race. Nineteen-year old men (n = 27,978) were selected and investigated by means of questionnaires and clinical examinations. The prevalence of each symptom was studied and tried to determine the effects of the TMD-associated signs on the TMD signs. The indices allocated to reflect the TMD signs and symptoms and the others were dichotomized for bivariate analysis. The predictor variables were headache, neck pain, referred pain, stress, past trauma history in the TMJ, past TMJ dislocation, bruxism, and clenching. The outcome variables were mouth opening limitation, TMJ pain on rest, and TMJ pain during function. RESULTS: The incidence of masticatory muscle stiffness was 17.8%; TMJ sounds, 14.3%; headache, 7.2%; neck pain, 13.5%; bruxism, 8.4%; and clenching, 9.9%. Stress occurred in 12.8%, past trauma history in 11%, and previous joint dislocation in 2.5%. The experience of dislocation in the TMJ was found to be the most important risk factor in terms of mouth opening limitation (odds ratio, 4.08, P <.0001), joint pain during function (odds ratio, 5.50, P <.0001), and joint pain in the rest state (odds ratio, 4.63, P <.0001). Referred pain and the experience of trauma in TMJ were the secondary risk factors in terms of joint pain and referred pain and the stress in terms of mouth opening limitation. Considering referred pain can be induced by TMD, stress may be more related to mouth opening limitation (odds ratio, 2.18, P <.0001), and the experience of trauma in TMJ may be more related to pain in the rest state (odds ratio, 2.56, P <.0001) and during function (odds ratio, 2.47, P <.0001). CONCLUSIONS: The prevalence of TMD signs and symptoms as determined by this examination was in accord with the findings in women or mixed samples of other workers. Prior experience of a dislocated disc was found to be the most risky factor in TMD. Stress was related to limitations of mouth opening, and the experience of trauma in the TMJ was found to be related to pain in the joint region. Bruxism may not be a direct risk factor in TMD, and the clenching habit found to be more harmful than bruxism.     

Multivariate analysis of risk factors in relation to TMD symptoms

The epidemiological studies on risk factors for temporomandibular disorders (TMD) are still extremely lacking. Therefore, their aetiological significance has scarcely been documented. The aim of this study was to quantitatively investigate the relationship between hypothesized risk factors and the precipitation and perpetuation of TMD symptoms. The same 672 adults who participated in a previous study ( Matsuka et al., 1996 ) were selected for this study. All subjects had already answered a self‐administered questionnaire and the same questionnaire was sent to them 4 years after the first survey. The questionnaire failed to reach 58 subjects at the second survey. Of the remaining 614 subjects, 367 (166 males and 201 females with a mean age of 53·1 ± 14·2 years) returned the questionnaire, for a return rate of 59·8%. Information about three TMD symptoms [temporomandibular joint (TMJ) pain, limitation of mouth opening, TMJ noise] was obtained from the questionnaire, and fluctuation of these symptoms was assessed by comparing three pairs of answers between the first and second surveys. Information about 18 hypothesized risk factors for TMD (age, sex, trauma, bruxism, malocclusion, oral habit, etc.) were also obtained from the questionnaire at the first survey. To evaluate how strongly each risk factor was associated with precipitation and perpetuation of TMD symptoms, odds ratio of each risk factors for precipitating or perpetuating TMD symptoms was calculated by means of logistic regression analysis. Statistically significant risk factors for precipitating TMD symptoms were lip biting for TMJ pain (3·65) and trauma for limitation of mouth opening (3·20), and statistically significant risk factors for perpetuating TMD symptoms were female for TMJ pain (4·50) and TMJ noise (3·85) (odds ratio in parenthesis). The possible aetiological significance of these factors in TMD should be validated by future research.     

Overbite and overjet are not related to self-report of temporomandibular disorder symptoms

Overbite and overjet, especially high or low values, have been found in some studies to be associated with temporomandibular disorders (TMD). This study evaluates the relationship between overbite/overjet and three TMD self-report measures (pain, joint noises, limited mouth-opening). Subjects were from two population-based cross-sectional studies (3033 subjects). After adjustment for age and gender, high or low values of overbite were not associated with an increased risk of self-reported TMD pain as compared with a reference category of a normal overbite of 2 to 3 mm (-8 to -1 mm, odds ratio = 0.36, 95% confidence interval = 0.05-2.76; 6 to 15 mm, odds ratio = 1.08, 95% confidence interval = 0.68-1.72). Similar non-significant results were found for overjet and TMD pain, and for the association of overjet/overbite and joint noises or limited mouth-opening. This study provides the strongest evidence to date that there is no association between overbite or overjet and self-reported TMD.     

Prevalence of tinnitus according to temporomandibular joint disorders and dental pain: The Korean National Population‐based Study

Some studies have reported that temporomandibular joint disorder (TMD) is related to tinnitus. However, there is no study of the relationship and prevalence of dental pain and tinnitus. We evaluated the associations between the prevalence of tinnitus and TMD and dental pain by analysing the Korean national health survey. We analysed totally 11 745 participants. The presence of tinnitus, TMD symptoms and dental pain was surveyed by self‐assessment questionnaires from all the participants. Multivariable regression analysis was applied to acquire odds ratios (OR) and 95% confidence intervals (CI). The prevalence of tinnitus was higher in the subjects with dental pain (21.1%), TMD (22.5%) and both symptoms (31.2%) than subjects without those symptoms (19.6%). After adjusting for all covariates, subjects with TMD had tinnitus 1.6 times more than subjects without TMD. In the subanalysis, age group more than 65 years, women, and obese subjects had tinnitus more than men, age group <65, and non‐obese subjects, respectively. TMD alone and both dental pain and TMD were associated with tinnitus (OR = 1.389 and 95% CI 1.054‐1.832 and 2.206 and 1.637‐2.974, respectively). Subjects with TMD had more tinnitus than subjects without TMD. Moreover, subjects with dental pain in addition to TMD had increased prevalence of tinnitus than TMD alone.     

Review of temporomandibular joint pathology. Part I: classification, epidemiology and risk factors

Pathology of the temporomandibular joint (TMJ) affects an important part of the population, though it is not viewed as a public health problem. Between 3-7% of the population seeks treatment for pain and dysfunction of the ATM or related structures. The literature reports great variability in the prevalence of the clinical symptoms (6-93%) and signs (0-93%), probably as a result of the different clinical criteria used. In imaging studies it is common to observe alterations that have no clinical expression of any kind. Radiographic changes corresponding to osteoarthrosis are observed in 14-44% of the population. Age is a risk factor, though with some particularities. In elderly patients there is an increased prevalence of clinical and radiological signs, though also a lesser prevalence of symptoms and of treatment demands than in younger adults. Approximately 7% of the population between 12 and 18 years of age is diagnosed with mandibular pain-dysfunction. Temporomandibular dysfunction (TMD) is more frequent in females. No clear relationship has been established between occlusal alterations and TMJ disease. Only disharmony between centric relation and maximum intercuspidation, and unilateral crossbite, have demonstrated a certain TMJ disease-predictive potential. Both local and systemic hyperlaxity has been postulated as a possible cause of TMD. Parafunctional habits and bruxism are considered risk factors of TMD with odds ratios (ORs) of up to 4.8. Psychophysiological theory holds stress as a determinant factor in myofascial pain. Genetic factors and orthodontic treatment have not been shown to cause TMD.     

Gender differences in temporomandibular disorders in adult populational studies: A systematic review and meta‐analysis

The objective of this study was to systematically evaluate gender differences in the prevalence of TMD. A systematic review was performed in PubMed, EMBASE, Web of Science and LILACS in duplicate by two independent reviewers. The inclusion criteria were cross‐sectional studies that reported the prevalence of TMD for men and women and that used the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I group diagnostic criteria:(group I = muscle disorders; group II = disc displacements; group III = arthralgias/arthritis/arthrosis).To be eligible for inclusion, studies must include adult individuals (>18 years) from a non‐clinical population (ie without pre‐diagnosis of TMD); in other words, from population‐based studies. There were no restrictions on the year and language of publication. The quality of the articles was assessed by an adapted version of the Newcastle‐Ottawa Scale(NOS), and the publication bias was assessed by a funnel plot graph. Data were quantitatively analysed by meta‐analysis using odds ratio (OR) as the measure effect. The electronic search retrieved a total of 6104 articles, of which 112 articles were selected for full‐text reading according to the eligibility criteria. By means of manual search, one study was retrieved. Five articles were selected for meta‐analysis with a combined sample of 2518 subjects. Women had higher prevalence of TMD in all RDC/TMD diagnostic groups. The meta‐analysis yielded the following results: (a) OR = 2.24 for global TMD (groups I, II and III combined), (b) OR = 2.09 for group I, (c) OR = 1.6 for group II and (d) OR = 2.08 for group III. The importance of gender in the development of TMD has been demonstrated, with a two times greater risk of women to develop it as compared to men.     

A clinical comparison of internal joint disorders in patients presenting disk-attachment pain: prevalence,characterization, and severity of bruxing behavior

This study clinically documents the presence of disk-attachment pain (DAP) related to the severity of bruxism and to the prevalence of internal joint disorders in patients and controls. The sample consisted of 394 temporomandibular disorder (TMD) and bruxing behavior patients and 104 nonbruxer control subjects. The TMD group was subdivided in a group of 109 disk-attachment pain patients and 285 bruxing behavior-nonDAP groups. The second reference group was a sample of 104 nonbruxing behavior subjects. Comprehensive evaluations (including history of signs and symptoms), use of questionnaires, clinical examination, palpation of muscles and joints, classification of bruxing behavior by the degree of severity, and diagnostic tests were performed in patients and controls. There was a prevalence of disk-attachment pain in the group of TMD and bruxing behavior patients. The degree of jaw opening was lower in the DAP group as compared to the TMD/bruxism-nonDAP group and controls. The mean Visual Analog Scale (VAS) value for the joint pain complaints was slightly elevated in the DAP group as compared to the TMD/bruxism-nonDAP group. Specific masticatory disorders including difficulties to open, pain on opening, chewing pain, fatigue on chewing, jaw deviation to opening, and change to a soft diet, were significantly more prevalent in the DAP group as compared to the other reference groups. Our conclusions are based upon a review of the literature and on the results of this study: a. DAP is a relatively well defined stage of internal joint derangement (IJD); and b. compared to other groups, DAP patients as a subgroup are relatively more impaired by their masticatory and other functional disorders. This study provides strong support to other studies and demonstrates that DAP is a well-differentiated and severe internal joint disorder.     

Pharmacological treatment of oro‐facial pain – health technology assessment including a systematic review with network meta‐analysis

This health technology assessment evaluated the efficacy of pharmacological treatment in patients with oro‐facial pain. Randomised controlled trials were included if they reported pharmacological treatment in patients ≥18 years with chronic (≥3 months) oro‐facial pain. Patients were divided into subgroups: TMD‐muscle [temporomandibular disorders (TMD) mainly associated with myalgia]; TMD‐joint (TMD mainly associated with temporomandibular joint pain); and burning mouth syndrome (BMS). The primary outcome was pain intensity reduction after pharmacological treatment. The scientific quality of the evidence was rated according to GRADE. An electronic search in PubMed, Cochrane Library, and EMBASE from database inception to 1 March 2017 combined with a handsearch identified 1552 articles. After screening of abstracts, 178 articles were reviewed in full text and 57 studies met the inclusion criteria. After risk of bias assessment, 41 articles remained: 15 studies on 790 patients classified as TMD‐joint, nine on 375 patients classified as TMD‐muscle and 17 on 868 patients with BMS. Of these, eight studies on TMD‐muscle, and five on BMS were included in separate network meta‐analysis. The narrative synthesis suggests that NSAIDs as well as corticosteroid and hyaluronate injections are effective treatments for TMD‐joint pain. The network meta‐analysis showed that clonazepam and capsaicin reduced pain intensity in BMS, and the muscle relaxant cyclobenzaprine, for the TMD‐muscle group. In conclusion, based on a limited number of studies, evidence provided with network meta‐analysis showed that clonazepam and capsaicin are effective in treatment of BMS and that the muscle relaxant cyclobenzaprine has a positive treatment effect for TMD‐muscle pain.     

颞下颌关节紊乱的影像学特征：锥形束CT和MRI效能比较

目的：分析颞下颌关节紊乱（temporomandibular joint disorder, TMD）的锥形束CT(cone-beam CT, CBCT)和磁共振成像（magnetic resonance imaging, MRI）特征,对两者的影像特征进行比较。方法：收集2018年8月—2020年5月在南通市口腔医院治疗的45例TMD患者的临床资料,所有患者均于2周内完成CBCT和MRI检查,统计所有患者颞下颌关节（temporomandibular joint, TMJ）和咀嚼肌病变在CBCT和MRI上的特征（包括关节间隙狭窄、骨质破坏、骨质增生硬化、髁突变形、骨质囊样变、关节盘移位、关节囊积液和咀嚼肌病变）,并对两者的影像学特征进行比较。采用SPSS 25.0软件包进行数据统计分析。结果：TMD临床分类Ⅰ类疼痛性疾病31例（68.9%）,Ⅱ类关节疾病14例（31.1%）。45例患者90个关节中,MRI检出存在TMJ和咀嚼肌病变数（71/90）显著高于CBCT检出的病变数（58/90）(P=0.032),其中MRI检出关节盘移位（19/90）、关节囊积液（28/90）和咀嚼肌水肿（...