The correlation of temporomandibular joint sounds with joint morphology in fifty-five autopsy specimens

Joint sounds from 55 fresh temporomandibular joint autopsy specimens were correlated with the macroscopic examination of joint morphology. Fifty-eight per cent of the joints were silent. Two thirds of these showed normal superior disc positions and remodeled articular surfaces, whereas one third exhibited anterior disc displacement. Twenty per cent of the joints elicited clicking and showed anterior disc displacement. Twenty-two per cent of the joints elicited crepitation and exhibited mostly arthrosis of the articular surfaces and perforation of the discs. Our results confirm previous statements that clicking and crepitation may be looked upon as signs of abnormal joint morphology, clicking indicating anterior disc displacement and crepitation usually indicating arthrosis. Absence of sound alone, however, should not be accepted as an indication of a normal joint.     

Temporomandibular joint sounds in patients with disc displacement

Temporomandibular joint sounds have been viewed as signs of different pathological changes. However, the correlation between joint sounds on the one hand and function and morphology of the joint on the other, are not well documented. We have therefore presurgically recorded sound from 35 operated joints with disc displacement and have studied arthrographically and during surgery the position, function and configuration of the disc as well as arthrotic changes. 12 joints were silent, 12 elicited reciprocal clicking, 3 single clicking, and 8 crepitation. Joints with reciprocal clicking consistently showed disc displacement with reduction and silent and crepitating joints showed disc displacement without reduction. All joints with reciprocal clicking as well as most silent joints demonstrated non-arthrotic articular surfaces, whereas crepitation was recorded in both arthrotic and non-arthrotic joints. Our results implied that crepitation is a rather unreliable sign of arthrosis. Reciprocal clicking can be considered as an accurate sign of reduction of anteriorly displaced discs. However, neither the degree of displacement nor the degree of deformation of the disc could be disclosed by analysis of the sound. This information can only be obtained by further examination, such as arthrotomography.     

Temporomandibular joint: surgically created disk displacement causes arthrosis in the rabbit.

To document a causal relationship between temporomandibular joint disk displacement and arthrosis, the disk was surgically displaced in one temporomandibular joint in each of three rabbits. The rabbits were sacrificed after 4 weeks and the mandibular condyles were studied radiographically and histologically. All three joints that underwent disk displacement had radiographic and histologic evidence of arthrosis, which included erosion of the bone, irregularity and fissure formation of the articular soft tissue cover, disruption of the subchondral layer of cartilage cells, and chondrocyte proliferation. No radiographic or histologic changes occurred in the joints that were untouched. The results suggest that surgically created disk displacement can cause arthrosis in the temporomandibular joint of the rabbit.     

Internal derangement of the temporomandibular joint: morphologic description with correlation to joint function

Internal derangement of the temporomandibular joint has mainly been studied arthrographically from the standpoint of anterior disk displacement with or without reduction. Frequent clinical observations of disk deformation in joints with internal derangement implied the need for a systematic study of morphologic alterations associated with internal derangement. Therefore, morphology, internal derangement, and joint function were studied in 58 randomly selected autopsy specimens of the temporomandibular joint. The results showed that joints with superior disk position rarely demonstrated morphologic alterations. In joints with partially anterior disk position, disk deformation occurred somewhat more frequently (31%) and was consistently located in the part of the disk that was positioned anteriorly. Joints with completely anteriorly positioned disks showed disk deformation in 77% and irregularities of the articular surfaces in 65%. It appears that anterior disk position precedes disk deformation. Therefore, early causal treatment to correct symptomatic internal derangement appears indicated to decrease the possibility of development of disk deformation. Disk deformation was also closely associated with disturbed joint function and should therefore be an important consideration when one is planning treatment of internal derangement of the temporomandibular joint.     

Temporomandibular joint comparative imaging: diagnostic efficacy of arthroscopy compared to tomography and arthrography

This comparative imaging study of the TMJ was conducted to examine the diagnostic data obtained from arthroscopy as compared to data from tomography and arthrography. Six joints from cadaver material were imaged by each technique and subsequently dissected. Each technique had value, but none was comprehensive. Tomography was the technique of choice for imaging osseous changes. Double joint space arthrotomography was useful for examining articular disk position and morphology. Diagnostic arthroscopy, through direct visualization of surface morphology, showed localized surface pathosis, such as synovitis; provided data on the location and size of disk perforations; and contributed reliably to a diagnosis of disk displacement on the basis of associated pathosis such as stretching of the posterior attachment.     

Treatment of temporomandibular joint dysfunction by intraoral vertical ramus osteotomy

The purpose of this study was to determine if the intraoral vertical ramus osteotomy is an effective treatment for anterior disk displacements with reduction and associated temporomandibular joint pain and dysfunction. Success with this procedure was predicated on producing a more functional articular disk-condyle relationship by anterior and inferior repositioning of the condyle. The prospective study was undertaken of nine (eight female and one male) patients (mean age of 25.8 years) with anterior disk displacement with reduction and associated temporomandibular joint pain and dysfunction (mean duration of pain of 6.8 years). History, clinical dysfunction, and pain indices were used to determine the frequency and severity of temporomandibular joint dysfunction. The incidence of ear pain, muscle fatigue, tinnitus, headaches, and clicking was also assessed. The severity of the pain experience in the masticatory muscles and temporomandibular joints was evaluated through the use of a pain index. The severity of the pain experience and temporomandibular joint dysfunction in all of the patients was significantly reduced or totally eliminated during the period of followup. Surgical treatment of anterior disk displacement with reduction by intraoral vertical ramus osteotomy resulted in improved temporomandibular joint function and resolution of symptoms.     

The role of the disk in sheep temporomandibular joint ankylosis.

OBJECTIVE: The purpose of this study was to determine the role of the disk in intraarticular ankylosis of the temporomandibular joint. STUDY DESIGN: Twelve adult sheep were divided into 2 groups. In group 1, removal of the temporal and condylar articular surfaces was performed on the right temporomandibular joint and the disk was maintained; in group 2, removal of the articular surfaces and diskectomy were performed on the right temporomandibular joint. One sheep from each group was killed just after surgery and 5 sheep from each group were killed at 3 months. The joints were examined radiologically, macroscopically, and histologically. The range of jaw movements was recorded preoperatively and at sacrifice. RESULTS: Each of 2 sheep in group 2 had lost 4% of their body weight by 3 months; all of the other sheep maintained or increased their weight. The range of jaw motion to the right was significantly lower in group 2 than in group 1 (P<.01). In group 1, fibrous repair of the articular surface and regeneration of the condylar head was seen. In group 2, each of the joints showed a total fibrous ankylosis with some calcification. There was a statistically significant difference in radiologic score between the groups (P<.0001). Histologic scores for group 1 demonstrated significantly lower scores on the degree of ankylosis scale and degree of calcification scale (P<.0001). CONCLUSIONS: This study showed that the presence of the disk prevented the development of fibrous intraarticular ankylosis of the temporomandibular joint.     

Clinical and arthrographic evaluation of temporomandibular joint sounds

Two hundred five patients were examined for temporomandibular joint pain and dysfunction. Arthrograms were performed on 222 joints (188 unilateral and 17 bilateral). Patients with joint sounds suspected of being caused by meniscus displacement with reduction were evaluated. Seventy-two patients (38%), were suspected of "clicking" (a reducing meniscus), but only 53 had arthrographic findings of a reducing meniscus. Further evaluation of this patient group revealed that only 41 probably could be candidates for a protrusive splint. This represents only 57% (41 of 72) of patients with "clicking" who may be candidates for protrusive splint treatment.     

Temporomandibular joint sounds and condyle/disk relations on magnetic resonance images.

This study compared the condyle/disk relationships on magnetic resonance images (MRIs) in a group of subjects with completely silent temporomandibular joints (TMJ) when tested clinically with those in subjects with readily discernible TMJ sounds. The sounds were recorded with an accelerometer as the transducer. Selected degrees of jaw separation were electronically determined and recorded with interocclusal wafers for use with the imaging process. Of the "silent joints" 89% were found to have sounds when tested with the accelerometer. These "subclinical" sounds tended to be of shorter duration and occurred at a greater degree of vertical opening than the clinically discernable sounds. The MRIs of the group with clinically discernable sounds tended to show a change in the relationship between the head of the condyle and the intermediate zone of the disk, at the degree of jaw separation of the sound occurrence, whereas no condyle/disk change occurred in the group with "clinically silent joints." It is likely that all joints create sound during function. The different characteristics of the subclinical sounds versus the clinical sounds may indicate differing sound origins.     

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.     

Multifactorial analysis of differences in temporomandibular joint hard tissue anatomic relationships between disk displacement with and without reduction in women.

STATEMENT OF PROBLEM: Without multifactorial models, it is difficult to resolve whether hard tissue tomographic relationships can distinguish differences between temporomandibular joint (TMJ) internal derangement diagnoses. PURPOSE: The purpose of this study was to use multifactorial models to examine whether there are hard tissue anatomic and orthopedic characteristics that distinguish temporomandibular joints with disk displacement with reduction from disk displacement without reduction. MATERIAL AND METHOD:. TMJ tomograms from female patients who had unilateral disk displacement diagnosed with (n = 84) or without (n = 78) reduction were compared with the use of 14 linear and angular measurements and 8 ratios. A representative classification tree model was tested for fit with sensitivity, specificity, accuracy, and likelihood accountability, and the results were compared with a multiple stepwise logistic regression model and univariate analysis. RESULTS: Disk displacement without reduction joints had longer mean postglenoid fossa heights (P<.0005), greater mean fossa depth (P<.017), and narrower mean absolute superior joint spaces (P<.041) than disk displacement with reduction joints (univariate t test). The classification tree had 4 terminal nodes; to differentiate the joints, it used the eminence radius and the absolute superior joint space to anterior joint space ratio subordinate to the postglenoid process height. The tree model accounted for 31.4% of the likelihood (Rescaled Cox and Snell R(2)) with 73.5% accuracy (sensitivity 82.6% and specificity 65.4%). Disk displacement without reduction joints had either deeper posterior fossa walls or posterior walls of average length combined with a superior-to-anterior joint space ratio of less than 0.83; this suggests a more open-wedge-shaped anterior joint space combined with a less-rounded articular eminence. In contrast, most disk displacement with reduction joints had shorter posterior fossa wall height combined with more equal or larger superior-to-anterior joint spaces. The logistic regression model was less accurate than the classification tree model (sensitivity 60.9%, specificity 66.7%) and accounted for only 9.9% of the likelihood (Rescaled Cox and Snell R(2)) and 63.6% accuracy. The postglenoid process height was the strongest differentiating factor in all models. CONCLUSION: Hard tissue relationships revealed by central tomogram sections were able to model notable differences between disk displacement with and without reduction joints when examined as contingency-based multifactorial systems.     

A study of factors for successful splint capture of anteriorly displaced temporomandibular joint disc with disc repositioning appliance

The purpose of this study was to analyse the factors which influenced the success of disc recapture by the insertion of a disc repositioning appliance. Fifty-one joints with joint clicking that occurred at both middle to late opening and late closing (near maximum cuspation) of the mandible were splinted with a mandibular full-coverage repositioning appliance. The clinical and MR findings were compared between the joints with successful and unsuccessful splint disc capture. Thirty-two clicking joints with reducibly displaced discs (DDWR) had successful disc recapture, while six of 19 joints with displaced disc without reduction (DDWOR). Unsuccessful joints with DDWOR had significantly higher prevalence of deformed disc and joint effusion, higher VAS quantitative pain score, and severe disc displacement especially in medial part of the joint (P < 0.05). From the results of this study joints with DDWR can be expected to have successful disc recapture with the insertion of the appliance. In joints with DDWOR, presence of inflammatory conditions, changed disc morphology and extensive disc displacement in medial part of the joint are negative factors.     

髁突运动中心大张口轨迹与关节窝形态的关系及临床应用探讨

目的　探讨髁突运动中心大张口轨迹与关节窝形态的关系 ,对TMD患者髁突运动中心轨迹特征进行初步研究。方法　利用自行开发的髁突运动中心轨迹显示分析系统 ,分别以运动中心、终末绞链轴点作为参考点 ,观察 10名健康人和 7例临床检查怀疑盘前移位的TMD患者大张口轨迹 ,与磁共振成像得到的相应关节窝形态及关节盘位置诊断结果进行比较。结果　健康人左右侧运动中心轨迹与关节窝形态曲线重合率分别为 80 % (8/ 10 )和 90 % (9/ 10 ) ;终末绞链轴点轨迹与关节窝形态重合率均为 0 (0 / 10 )。TMD患者中 ,11侧盘前移位关节 ,除 1侧可复性盘前移位关节外 ,髁突运动中心轨迹均与正常的轨迹明显不同 ,出现各种改变 ;3侧正常盘位关节 ,髁突运动中心轨迹均与健康人的轨迹相似。结论　运动中心轨迹较终末绞链轴点个体稳定 ,可认为是较理想的研究髁突运动轨迹的参考点     

The acoustical characteristics of the normal and abnormal temporomandibular joint

This paper describes the results of a clinical study that recorded and analyzed sounds emitted from the temporomandibular joint (TMJ) during simple function as a means for differentially diagnosing disorders of the joint. The technique is based on the principle that each different disorder of the TMJ produces a different effect on the mechanical relationship between the articulating surfaces of the joint, and that these mechanical effects can be determined by analyzing joint sounds in relation to joint movement. A total of 79 patients (101 joints) were studied; 32 (46 joints) were diagnosed as having extracapsular disorders, (primarily MPD), 27 (32 joints) were diagnosed as having a displaced disc with reduction, nine (10 joints) were diagnosed as having a displaced disc without reduction, and 11 (13 joints) were diagnosed as degenerative disease (osteoarthritis/arthrosis). In addition, 25 adults (50 joints) with normal TMJs were included as controls. The results of this study demonstrated that each specific disease of the TMJ is characterized by a unique relationship between the sounds propagated by the joint and the movement of the joint. Essentially, an extracapsular disease was characterized by acoustic quiescence during natural (as opposed to maximal) jaw movement, an internal derangement by a usually symmetrical short duration click/reciprocal click, or random click complex, depending on the subcategory of the disorder, and a degenerative disease by a long duration noise during either or both jaw opening and closing. The data further suggest that the technique serves to reflect the mechanical events (and abnormalities) that are involved in function of the diseased joint and has potential for use as a clinical diagnostic tool.     

Localization of TMJ sounds to side

Differential diagnosis depends in cases with disk displacement on accurate identification of sound source. Mistakes may occur when clicking from one temporomandibular joint (TMJ) is heard on both sides of the head at auscultation and neither examiner nor patient, is sure about side. The hypothesis was that the head tissues affect spectral characteristics of TMJ sounds and that differences due to different positioning of sensors can be used in localization of source. The aim was to compare bilateral electronic recordings of unilateral TMJ sounds to obtain and compare attenuation, phase shift and time delay. Recordings were made from 12 subjects with unilateral clicking. Small electret condenser microphones, bandwidth 40-20 000 Hz, were placed at the openings of the auditory canals and the sounds were recorded at a sampling rate of 48 000 Hz. The head tissues acted as a filter causing a frequency dependent attenuation and phase shift. There was a time difference between the ipsi- and the contra lateral recordings, the latter always having a longer delay time (range 0.2-1.2 ms, group mean 0.68 ms, s.d. 0.292 ms). In conclusion, spectral analysis of bilateral electronic TMJ sound recordings is of diagnostic value when bilateral clicking is heard at auscultation and can help to avoid diagnosing a silent joint as clicking.     

Timing of temporomandibular joint sounds in orthodontic patients

The consistency of occurrence and also the timing of TMJ sounds during jaw opening and closing were studied by means of an audio-visual sound recording system in an attempt to address the possible causes of temporomandibular joint (TMJ) sounds. From a group of 347 orthodontic patients, 104 were found to have medium- or high-amplitude TMJ sounds during jaw opening or closing. Most patients (53%) had reciprocal clicking--that is, a single sound on opening and on closing; another 12% had multiple sounds on opening or closing; 22% had a single closing sound; and 13% had a single opening sound. Sounds occurred at all degrees of jaw opening throughout this sample, but in most patients opening sounds tended to be closer to maximum opening, whereas closing sounds tended to occur in the middle of the closing movement. No statistically significant association was found between the timing of the opening and closing sounds. In 42.3% of patients, the sound was inconsistent in its occurrence on successive opening and closing cycles. Twenty-three percent of patients reported pain, jaw locking, or limitation of movement, but these were not associated with the timing of the opening sound. The findings suggest that the reciprocal click, widely associated with anterior disc displacement with reduction, was relatively common, but that other explanations for the joint sounds should also be considered. Conversely, a large variation may exist in the timing and the occurrence of sounds in patients with anterior disc displacement in the absence of pain and limitation of movement.     

Comparison of magnetic resonance imaging, arthrotomography and clinical and surgical findings in temporomandibular joint internal derangements

Twenty-four temporomandibular joints were evaluated by means of tomography and magnetic resonance imaging (MRI). Seventeen of these joints were also examined with the use of arthrotomography. Meniscus surgery was carried out on 13 of the temporomandibular joints. The three imaging techniques were compared for diagnosis of disk displacement, of degenerative joint disease, and of perforations. All imaging techniques were compared with clinical and surgical findings. MRI was as accurate as arthrotomography in confirming disk displacement. MRI was more accurate in disclosing gross arthrosis than tomography. The best use of arthrography was in disclosing perforations. The best correlation to surgical findings was shown by the clinical examination.     

Temporomandibular joint click sound and magnetic resonance-depicted disk position: Which relationship?

AIMS: The aim of this work was to evaluate the agreement between temporomandibular joint click sound and MR diagnoses of different disk positions. METHODS: One hundred ninety-four (N=194) patients seeking treatment for temporomandibular disorders at the TMD Clinic, Department of Maxillofacial Surgery, University of Padova, Italy, underwent a bilateral magnetic resonance of the temporomandibular joints. The presence of click sounds was clinically assessed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and put into relation with different magnetic resonance (MR) diagnoses of disk-condyle position by means of permutation tests. RESULTS: The proportion of joints with reducing and non-reducing disk displacement which provided a click sound during the clinical assessment was similar (45.6% vs. 48.9%, respectively), while the prevalence of the two MR diagnoses in joints with click sound were strongly different (25.3% vs. 40.1%, respectively. Thus, the MR diagnosis which appears to be more positively associated with click sounds is disk displacement without reduction. CONCLUSION: There is a weak form of dependence between click and MR diagnosis, and the MR diagnosis of DDNR seems to be more positively associated with the presence of click sounds than the other categories, which did not show significant positive associations with click (i.e. there is negative association between click presence and normal disk position and no association between click presence and DDR joints.     

The wave forms of temporomandibular joint sound clicking and crepitation

summary The aim of the present study was to determine the sound wave forms which correspond to auscultatory findings of temporomandibular joint (TMJ) clicking and crepitation. Such knowledge is important when selecting parts of digital recordings for spectral analysis. Electronic digital recordings were made with a sampling rate of 44 100 Hz from 60 subjects, including 51 patients referred for suspected rheumatological disease and nine healthy subjects. Accelerometers with the bandwidth 20–3600 Hz were used for all subjects and complementary recordings were made from a subgroup of nine subjects using a measurement microphone with the bandwidth 20–20 000 Hz. The clicking sounds could be classified into different types according to differences in temporal period duration ( T ) as measured on the analogue display. One type of clicking, found in 51% of the patients, had a T of 2–20 ms. Another type, found in 70% of the subjects, had a T of less than 1 ms, often as low 0.2 ms. This type of clicking was not seen at all in the analogue display if the sampling rate was below 3 000 Hz. The character of the two types of clicking differed: the short duration sounds had a very high pitch, while the pitch of the longer duration sound was lower. Crepitation was found in 63% of the subjects and was observed to be composed of a series of short duration sounds, occurring with brief (less than 10 ms) intervals. It is concluded that the accelerometer (or microphone) bandwidth should cover the entire audible range (20–20 000 Hz), and that sampling rates must be much higher than 3000 Hz, and preferably greater than 10 000 Hz, before the true significance of electronically recorded joint sounds/vibrations can be determined.