Clinical findings related to morphologic changes in TMJ autopsy specimens

The need for integrated research autopsies in the era of precision oral medicine

BACKGROUND

Autopsy has benefited the practice of medicine for centuries; however, its use to advance the practice of oral health care is relatively limited. In the era of precision oral medicine, the research autopsy is poised to play an important role in understanding oral-systemic health, including infectious disease, autoimmunity, craniofacial genetics, and cancer.

TYPES OF STUDIES REVIEWED

The authors reviewed relevant articles that used medical and dental research autopsies to summarize the advantages of minimally invasive autopsies of dental, oral, and craniofacial tissues and to outline practices for supporting research autopsies of the oral and craniofacial complex.

RESULTS

The authors provide a historical summary of research autopsy in dentistry and provide a perspective on the value of autopsies for high-resolution multiomic studies to benefit precision oral medicine. As the promise of high-resolution multiomics is being realized, there is a need to integrate the oral and craniofacial complex into the practice of autopsy in medicine. Furthermore, the collaboration of autopsy centers with researchers will accelerate the understanding of dental, oral, and craniofacial tissues as part of the whole body.

CONCLUSIONS

Autopsies must integrate oral and craniofacial tissues as part of biobanking procedures. As new technologies allow for high-resolution, multimodal phenotyping of human samples, using optimized sampling procedures will allow for unprecedented understanding of common and rare dental, oral, and craniofacial diseases in the future.

PRACTICAL IMPLICATIONS

The COVID-19 pandemic highlighted the oral cavity as a site for viral infection and transmission potential; this was only discovered via clinical autopsies. The realization of the integrated autopsy's value in full body health initiatives will benefit patients across the globe.

Assessment of Morphologic Change of Mandibular Condyle in Temporomandibular Joint Osteoarthritis Patients with Stabilization Splint Therapy: A Pilot Study

(1) Background: The purpose of this study was to evaluate the 3-dimensional bony changes of the mandibular condyle in temporomandibular joints-osteoarthritis (TMJ-OA) patients treated with stabilization splint (SS) therapy using shape correspondence analysis. (2) Methods: A total of 27 adult patients (2 men and 25 women) with a mean age of 24.6 ± 3.9 years were included in this study. All patients were diagnosed with TMJ-OA and were treated with an SS. Cone-beam computed tomography data of the condylar head before and after SS therapy from 42 condyles (15 bilateral and 12 unilateral TMJ-OA) were used for the analysis. For the performance shape correspondence analysis (SPHARM-PDM), statistical differences were performed using the one-way analysis of variance and Scheffe post hoc tests. (3) Results: After SS treatment in TMJ-OA patients, bone resorption of the condyle head surface was predominant in the anterosuperior, superolateral, and superior areas, and bone formation was superior in the lateral, medial, posterosuperior, and posteromedial areas. The change in the condylar volume between the two groups was not statistically significant. (4) Conclusions: After SS treatment in TMJ-OA patients, there was both bone resorption and bone formation on the mandibular condyle head surface, which induced morphological changes in the condyle head.

Temporomandibular Joint Osteoarthrosis: A Review of Clinical Aspects and Management

The symptoms of TMJ Osteoarthrosis/Osteoarthritis(TMJ OA) are characteristic and in most cases specific to the disorder. There is, however, an overlap of symptoms with other TMDs.Treatment of TMJ OA is generally directed towards management of the symptoms as the temporomandibular joint does retain the capacity throughout life to repair and remodel. Non-conservative and invasive treatment is only rarely necessary.It should be remembered that the mandibular condyle retains the capacity to repair and remodel throughout life and patients should be encouraged to bear this in mind. Conservative measures are usually sufficient to treat symptoms and a period of time should be allowed to elapse before undertaking a more aggressive treatment plan, which, in the overwhelming majority of patients, will not be necessary. This disorder should be approached on the terms of 'a quality of life issue' and treatment should be directed towards patient needs.

Association of radiographic and clinical findings in patients with temporomandibular joints osseous alteration

OBJECTIVES

To characterize the relationship between radiographic and clinical characteristics of patients with temporomandibular joint (TMJ) osseous changes.

MATERIALS AND METHODS

TMJ cone beam computed tomography (CBCT) images of 73 patients (142 joints) with changes in osseous component of TMJ were included in this study. Based on both clinical and radiographic findings, each TMJ was diagnosed as either non-degenerative joint disease (non-DJD) or degenerative joint disease (DJD) according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) criteria. The DJD group was further classified into two subgroups of osteoarthritis and osteoarthrosis. The data were analyzed using t test and Pearson's correlation. Level of statistical significance was set at 0.05.

RESULTS

Statistically significant relationships were found between TMJ crepitation sound and 4 radiographic characteristics of DJD. DJD group demonstrated statistically significant higher CBCT bone change score (BCS) and age. In contrast, there was no significant difference of BCS between osteoarthrosis and osteoarthritis groups within the DJD group.

CONCLUSIONS

Crepitation sounds and osseous changes in TMJ radiograph are confirmed to be important diagnostic criteria for TMJ DJD. However, degree of TMJ osseous changes does not correlate significantly with clinical pain symptom.

CLINICAL RELEVANCE

For TMJ DJD diagnosis, dentists should consider both clinical examination for TMJ crepitation and radiographic assessment for TMJ bony changes.

Anterior condylar remodeling observed in stabilization splint therapy for temporomandibular joint osteoarthritis

OBJECTIVE

To comparatively evaluate condylar surface bone formation and cortical thickening in patients with temporomandibular joint osteoarthritis, with or without stabilization splint (SS) therapy.

STUDY DESIGN

This retrospective study of 57 OA patients included 18 patients who had undergone SS therapy (SS group), compared with 39 patients that had not received SS therapy (non-SS group). To evaluate osseous changes on the condylar bone formation and cortical thickening, pre- and post-treatment cone beam computed tomography images of each patient were superimposed using voxel registration.

RESULTS

The SS group exhibited a higher ratio of bone formation in the anterior division of the condyle; the non-SS group exhibited mostly no change. The SS group was found to have higher frequencies of cortical thickening in the anteromedial, anterior-intermediate, anterolateral, posteromedial, and posterior-intermediate sections than the non-SS group.

CONCLUSIONS

SS therapy in temporomandibular joint osteoarthritis induced favorable bone remodeling in the anterior division of the condylar head.

Treatment of Joint Pain and Joint Noises Associated with a Recent TMJ Internal Derangement: A Comparison of an Anterior Repositioning Splint, a Full-Arch Maxillary Stabilization Splint, and an Untreated Control Group

Pain and joint noises associated with temporomandibular joint (TMJ) internal derangement are often treated by using an intra-oral splint. This study evaluated whether an anterior repositioning splint (AR splint) could be more effective in the treatment of these symptoms than a full-arch maxillary stabilization splint (FAMS splint), because of its capability to re-establish immediately the normal condyle/disk relationship. The authors treated 40 patients (average age 16.8; range 8.0-24.0) with confirmed internal derangement, joint pain, and joint noises in at least one TMJ for at least two months, with AR splint (20 subjects) or FAMS splint (20 subjects); 10 untreated patients comprised the control group. Joint noise, joint pain, and the intensity of pain were assessed using a visual analogic scale (VAS), and the pain was characterized (i.e., constant or chewing/biting pain) and evaluated monthly for eight months. Significantly fewer AR splint patients experienced pain after four months of treatment. A significantly lower intensity of pain was experienced by the AR splint patients after two months of treatment. Significantly fewer AR splint patients experienced chewing/biting pain after eight months of treatment. The frequency of joint noises decreased over time, with no significant differences between the groups. In conclusion, the AR splint seems to be more effective in decreasing pain, but it seems to make no difference in the treatment of joint noises.

Differences in Temporomandibular Joint Pain and Age Distribution Between Marrow Edema and Osteonecrosis in the Mandibular Condyle

This study investigated the differences of age distribution and temporomandibular joint (TMJ) pain between marrow edema and osteonecrosis in the mandibular condyle. Subjects consisted of 35 TMJs in 35 patients with abnormal bone marrow on MR images who were selected from a consecutive series of 527 patients with TMJ disorders. Proton density and T2-weighted MR images taken in the oblique sagittal and coronal planes were used to diagnose condylar marrow abnormalities and divide them into either edema or osteonecrosis. The differences in TMJ pain and age distribution for these two abnormalities were assessed with the one-sided Wilcoxon rank sum test with 0.05 alpha level. The degree of pain was higher in joints with marrow edema than in joints with osteonecrosis (p = 0.033). The mean age was higher in joints with osteonecrosis (p < 0.001). Our results suggest that there is more severe pain in TMJs with marrow edema of the mandibular condyle than in those with osteonecrosis. Since the patients with marrow edema have lower age, it also appears that marrow edema may be a precursor condition for osteonecrosis of the TMJ.

Timing interventions in relation to temporomandibular joint closed lock duration: a systematic review of 'locking duration'

Temporomandibular joint (TMJ) 'closed lock' (CL) is a clinical condition causing TMJ pain and limited mouth opening (painful locking) that is mostly attributed to disc displacement without reduction (DDwoR), or less commonly to anchored disc phenomenon (ADP). Both conditions are described clinically as CL that can be 'acute' or 'chronic' depending on the duration of locking. There is, however, no consensus about the duration of locking that defines the acute state and its effect on the success of interventions. This review paper, therefore, aims to provide: (i) a narrative review of the pathophysiological need for early intervention in DDwoR and the clinical implications of acute/chronic CL stages on the management pathway; (ii) a systematic review investigating the effects of locking duration on the success of interventions for CL management. Electronic and manual searches until mid-August 2013 were conducted for English-language studies of any design investigating the effects of non-surgical and surgical interventions for acute or chronic CL (DDwoR or ADP). A total of 626 records were identified, and 113 studies were included. Data extraction and quality assessment were completed for all included studies. Included studies were, however, heterogeneous and mostly of poor-quality leading to contradictory and inconsistent evidence on the effect of the duration of locking on treatment outcomes. Future high-quality trials investigating the effect of CL duration on treatment outcome are needed. At present, early intervention by 'unlock' mandibular manipulation seems to be the most practical and realistic approach that can be attempted first in every CL patient as an initial diagnostic/therapeutic approach.

Temporomandibular joint (TMJ) disc position in patients with TMJ pain assessed by coronal MRI

OBJECTIVES

To assess the position of the temporomandibular joint (TMJ) disc in patients with TMJ pain and compare it with equivalent published data of asymptomatic volunteers.

METHODS

The oblique coronal closed- and open-jaw MR images from 66 patients with TMJ pain were evaluated. Clinical examination followed the research diagnostic criteria for temporomandibular disorders. In all coronal images, the transverse condylar axis and the medial and lateral edges of the disc were determined using special software. Inter-rater agreement was calculated [two raters; inter-rater correlation coefficient (ICC)]. The presence of osteoarthrosis (OA) was determined by two independent raters. The influence of OA was estimated in patients (generalized estimation equation model). The results were compared with those of healthy volunteers (t-test). Differences between closed and open jaw in patients were analysed with the Wilcoxon matched-pair test.

RESULTS

The ICC was good for the transverse condylar axis (0.987) and the medial edge of the disc (0.799) and fair for the lateral edge (0.355). On average, the disc projected 5.5% to the medial side; laterally, the condyle was partially uncovered by the disc (-16.6%). In the open-jaw position, both the medial and the lateral edges shifted medially (to 17.6% vs -23.6%, Wilcoxon matched-pair test, p < 0.001). OA had no significant influence (generalized estimation equation model, p = 0.952). The disc position differed significantly from asymptomatic individuals (t-test, p < 0.001) who showed a medial disc position and full coverage of the condyle.

CONCLUSIONS

In patients with TMJ pain, the disc seems to be smaller and located less medially than in healthy volunteers. The extent of the medial shift on opening was similar.

Analysis of Criteria for MRI Diagnosis of TMJ Disc Displacement and Arthralgia

Aims. To improve diagnostic criteria for TMJ disc displacement (DD). Methods. The standard protocol for MRI diagnosis of DD, using a 12 o'clock reference position, was compared to an alternative protocol. The alternative protocol involves the functional relationship between the condyle and articular eminence, using a line perpendicular to the posterior slope of the eminence as a reference for disc position. The disc location was examined using both protocols, and disc diagnoses were compared in their relationship with joint pain. Statistical analyses included P value, sensitivity, specificity, odds ratio, and kappa statistic. Results. 58 MRIs were interpreted. 36 subjects reported arthralgia; 22 did not. Both protocols demonstrated significance (standard P = 0.004, alternative P < 0.001) for the ability to predict arthralgia. The odds of arthralgia increased in DD patients diagnosed by standard methods 9.71 times and in DD diagnosed by alternative means 37.15 times. The diagnostic sensitivity decreased 30% using the alternative versus the standard protocol (0.6389 versus 0.9444), while specificity increased 60% (0.9545 versus 0.3636). Conclusions. A stronger relationship occurs between DD and arthralgia when using a function-based protocol. The alternative protocol correctly identifies subjects without arthralgia, who by standard methods would be diagnosed with DD, as having nondisplaced discs, providing a more clinically relevant assessment of TMJ disc displacement.

MR evidence of characteristics in symptomatic osteoarthritis of the temporomandibular joint: increased signal intensity ratio on proton density-weighted images of bone marrow in the mandibular condyle

The purpose of this study was to clarify the presence of pain and a correlation between pain and characteristics of signal intensity of mandibular bone marrow in temporomandibular joints (TMJ) with osteoarthritis (OA). A total of 196 joints in 98 patients with TMJ disorders were examined using magnetic resonance imaging (MRI). A pain score and signal intensity on mandibular bone marrow were analyzed in the TMJ with OA. TMJ with OA showed a higher degree of pain compared to those without (p < 0.05). During opening, the joints in the higher signal intensity group showed a significantly higher degree of pain compared to the joints in the lower signal intensity group in those with OA on proton density weighted images (p < 0.05). It was concluded that TMJ with osteoarthritis is related to pain and that a symptomatic osteoarthritic TMJ can accompany bone marrow changes in the condyle, showing an increased signal on proton density weighted images.

Temporomandibular joint soft-tissue pathology, I: Disc abnormalities

The internal derangements are the most common noninflammatory abnormalities of the disc, observed even in asymptomatic subjects. Because the temporomandibular joint shows large adaptative and compensatory mechanisms over dysfunctional disc motion, these disorders may be asymptomatic or minimally evident for a long time. A careful clinical evaluation, reinforced by imaging findings, should help differentiate asymptomatic derangements from painful conditions that may require treatment.

Osseous abnormalities related to the temporomandibular joint

With the arrival of arthrography, computed tomography, and magnetic resonance imaging, diagnostic imaging of the temporomandibular joint has improved tremendously over the last 20 years. In patients with temporomandibular joint pain and dysfunction, the main focus was on meniscal pathology. The purpose of this article is to discuss several osseous abnormalities and demonstrate their association with temporomandibular joint pain and dysfunction.

Joint intracapsular disorders: diagnostic and nonsurgical management considerations

This article reviews common intracapsular temporomandibular disorders encountered in the dental practice. It begins with a brief review of normal temporomandibular joint anatomy and function followed by a description of the common types of disorders known as internal derangements. The etiology, history, and clinical presentation of each are reviewed. Nonsurgical management is presented based on current long-term scientific evidence.

MR imaging of temporomandibular joint dysfunction: a pictorial review

Temporomandibular joint (TMJ) dysfunction is a common condition that is best evaluated with magnetic resonance (MR) imaging. The first step in MR imaging of the TMJ is to evaluate the articular disk, or meniscus, in terms of its morphologic features and its location relative to the condyle in both closed- and open-mouth positions. Disk location is of prime importance because the presence of a displaced disk is a critical sign of TMJ dysfunction. However, disk displacement is also frequently seen in asymptomatic volunteers, so that other findings may be required to help make the diagnosis. These findings include thickening of an attachment of the lateral pterygoid muscle, rupture of retrodiskal layers, and joint effusion and can serve as indirect early signs of TMJ dysfunction. It is important for the radiologist to detect early MR imaging signs of dysfunction, thereby avoiding the evolution of this condition to its final stage, an advanced and irreversible phase that is characterized by osteoarthritic changes such as condylar flattening or osteophytes. Further studies conducted with the latest MR imaging techniques will allow a better understanding of the sources of TMJ pain and of any discrepancy between imaging findings and patient symptoms.

Sensitivity and specificity of a new MRI method evaluating temporo-mandibular joint disc–condyle relationships: an in vivo study

The aim of this study was to evaluate sensitivity and specificity of a new method to locate temporo-mandibular joint (TMJ) disc using magnetic resonance imaging (MRI) and analyze disc-condyle relationships, in asymptomatic subjects and patients with disc displacement. Twenty-nine sagittal MRI of 16 subjects, 8 asymptomatic volunteers and 8 subjects with anterior disc displacement, were carried out during controlled opening from intercuspal position up to a 25 mm opening. Selected sections were analyzed with a graphic computerized system of coordinates. The total surface area (TS) of disc section was separated into anterior surface area (AS) and posterior surface area. Areas were determined by computer. Two trained examiners drew images at random. The reliability of AS/TS ratio index was evaluated in a previous study. AS/TS ratio sensitivity (Se) and specificity (Sp) were calculated closed mouth, 5 mm open and 25 mm open mouth. Best sensitivity (Se=0.63) and specificity (Sp=0.81) were obtained when MRI was realized with closed mouth and 25 mm open mouth. Lower sensitivity was observed when MRI was performed either with closed mouth (Se=0.54) or 25 mm open mouth (Se=0.18). Lower specificity was observed with 5 mm open mouth (Sp=0.68). In conclusion, it was confirmed as well that MRI of anterior disc displacement should be performed with closed mouth and opened mouth. Thus, further studies are required to assess disc displacement and mechanical alterations and to evaluate the risk of direct damage on TMJ tissues.

The comparison between pains, difficulties in function, and associating factors of patients in subtypes of temporomandibular disorders

The aim of this study was to compare the multidimensional properties among subtypes of painful temporomandibular disorders (TMD): myofascial pain (group I), disc displacement (group II), arthralgia (group IIIa) and osteoarthritis (group IIIb). A total of 511 patients answered a battery of questionnaires, which included questions relating to intensity and duration of pain, the Japanese version of the McGill Pain Questionnaire, limitation of daily functions, the Hospital Anxiety and Depression Scale, the Eysenck Personality Questionnaire short-form and 34 items of behavioural contributing factors. Group IIIb showed significantly the highest age in all subtypes. Those in group I had higher depression scores than those in group II (P = 0.005). Group IIIa had a lower women's ratio than in group II (P = 0.001) and the patients showed a shorter pain duration than those in groups I (P = 0.000) and II (P = 0.001). Group IIIa patients also showed lower visual analogue scale (VAS) ratings for pain descriptors 'heavy' (P = 0.002) and 'tiring' (P = 0.004) than those of group I, and 'dull' (P = 0.005), 'heavy' (P = 0.001) and 'tiring' (P = 0.005) than those of group II. Group IIIa showed lower ratios of contributing factors of 'an awareness of grinding/clenching during sleep' (P = 0.000) and 'an awareness of clenching sensation when waking up at night' (P = 0.002) than those of group I, and also showed a higher ratio of 'a liking for a hard food' (P = 0.000) and lower ratio of 'talking for a long time on the telephone' (P = 0.001) than those of group II. In conclusion, although several properties were different between subtypes, the majority of them were similar in the four subtypes of TMD.

Effects of sagittal split ramus osteotomy on temporomandibular disorders in seventy-two patients

Preoperative and postoperative temporomandibular disorders (TMDs) were observed in 72 patients before surgical-orthodontic treatment and about 2 years after bilateral sagittal split osteotomy. Prevalence and degree of TMD were assessed using the modified clinical dysfunction index of Helkimo. A total of 49 women and 23 men (mean age 32 years) were included in the study. To find out which patients benefit most from the treatment, the sample was classified into subgroups--myogenous, arthrogenous, or both components of TMD. The prevalence of clicking and headache decreased significantly with the treatment, while the incidence of crepitation increased. In general, severity of the dysfunction was greatly reduced. Furthermore, multiple regression analysis showed that patients with excessive overjet and previous occlusal splint therapy benefit most from orthognathic treatment. In addition, patients with signs of mainly myogenous origin got more relief from their dysfunction than patients with mainly arthrogenous components of TMD. The results suggest that in patients with severe maxillomandibular discrepancy surgical-orthodontic therapy is a good choice of treatment for reducing myogenous TMD pain and discomfort.

Common abnormalities in temporomandibular joint imaging

Magnetic resonance imaging has evolved as a prime diagnostic method for soft-tissue abnormalities of the temporomandibular joint. The most common temporomandibular joint abnormalities are internal derangement and osteoarthritis, but there are many other reasons for pain and dysfunction that are often overlooked. The purpose of this paper is to illustrate several of these more unusual and less well-recognized causes for temporomandibular joint pain and dysfunction. For example, internal derangement is often seen in asymptomatic individuals. Another purpose is to illustrate the difference in magnetic resonance imaging of asymptomatic and symptomatic internal derangement.

Temporomandibular joint: MR imaging

Diagnostic imaging of TMJ has improved remarkably in the last 20 years. Various abnormalities related patient symptoms. Further studies using the latest imaging techniques will allow a better understanding of the sources of joint pain and the discrepancy between imaging findings and patient symptoms. For clinical practice, appropriate clinical examinations are needed to determine exactly which imaging findings are significant.

Factors affecting degeneration in human temporomandibular joints as assessed histologically

The influence of sex, age, tooth loss, and articular disc position on temporomandibular joint (TMJ) degeneration was evaluated in specimens collected at autopsy from 15 women and 38 men ranging in age from 15 to 92 yr. The position of the articular discs was classified as normal or abnormal, tooth loss was both counted and categorized. Degenerative changes of the articular tissues were assessed histologically and quantified, taking into account both the severity of structural alterations and their extension along the articular surface. This was recorded separately in the condyle, disc, and temporal component, three latero-medial joint regions, and putative load-bearing and non-load-bearing surfaces. Analysis of covariance with repeated measures served for testing contributing factors. It showed that the effects of sex and the number of missing teeth were insignificant, whereas age up to about 55-60 yr and reduction of dental arch length proved to be the most important factors. Load-bearing seemed to play a significant role mainly at younger ages, and the effect of disc position was significant, when internal derangement was combined with reduction of dental arch length. Thus, rising severity of TMJ degenerative changes appears to be associated primarily with increasing age. In addition, it may also depend on mechanical factors, in particular loss of molar support and, to a minor degree, abnormal disc position.

Matrix metalloproteinases in mild and severe temporomandibular joint internal derangement synovial fluid

OBJECTIVES

The first objective of this study was to verify the presence of and identify the molecular forms of matrix metalloproteinases (MMPs), including collagenases (MMP-1, MMP-8, and MMP-13) and gelatinases (MMP-2 and MMP-9), in the synovial fluid (SF) of mild and severe temporomandibular joint internal derangement (TMJ-ID). Another objective was to evaluate whether the SF MMPs are potential diagnostic markers that reflect the stage of intra-articular inflammation in the TMJ.

STUDY DESIGN

The subjects were 44 patients with mild (n = 16) or severe (n = 28) TMJ-ID; they were classified on the basis of subjective symptoms, clinical and radiographic findings, and surgical observations. The patients were surgically treated, and SF samples were collected immediately before the operation. The collagenase activity of SF samples was analyzed by means of a type I collagen degradation assay. The levels and molecular forms of the SF MMPs as well as the tissue inhibitors of MMPs (TIMP-1 and TIMP-2) were analyzed with Western immunoblotting and gelatin zymography.

RESULTS

The SF of both the mild and the severe TMJ-ID patients exhibited free collagenase activity and activity capable of further degrading the (3/4)(alphaA) fragments. Ninety-two-kilodalton proMMP-9 and its 121-kD complex form, as well as 72-kD proMMP-2 were significantly increased in the mild TMJ-ID group (P <.05 in all cases). Both 70- to 80-kD neutrophil type and 45- to 55-kD mesenchymal cell-type MMP-8 (corresponding to the latent and active forms) were observed in mild and severe TMJ-ID SF, but they predominated in mild TMJ-ID. Both MMP-1 and MMP-13 were observed in both groups, and in mild TMJ-ID SF the low-molecular weight forms of MMP-1 indicated activation of the enzyme.

CONCLUSIONS

The degradation of type I collagen in the TMJ is evidently due to the collective action of many collagenolytic MMPs present in the SF of patients with mild and severe TMJ-ID. The elevated levels of MMP-2, MMP-9, and MMP-8 in the SF of patients with mild TMJ-ID eventually reflect the active phase of TMJ destruction. These observations may have considerable diagnostic and therapeutic significance in the management of TMJ disorders.

Temporomandibular arthropathy: correlation between clinical signs and symptoms and arthroscopic findings

The clinical signs and symptoms of temporomandibular arthropathy were correlated with arthroscopic features of temporomandibular joint disease in 200 consecutive patients. The diagnostic accuracy of the selected clinical signs and symptoms was also tested with arthroscopy as the standard, and sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) were calculated. Pronounced osteoarthrosis was more frequently associated with joint crepitus (P < 0.001). Adhesions were more frequently associated with reduced maximum protrusion (P < 0.001). Crepitation was the only clinical sign that showed acceptable values for SE, SP, PPV, and NPV, and only in diagnosing advanced osteoarthrosis. The values for mild osteoarthrosis were low.

Microscopic changes in the retrodiscal tissues of painful temporomandibular joints

PURPOSE

The purpose of this study was to investigate the association between temporomandibular joint (TMJ) pain and histological changes in TMJs with disc displacement.

METHOD

Samples from capsules and posterior disc attachments from 27 TMJ pain patients who underwent surgery were compared with samples from seven asymptomatic persons.

RESULTS

On logistic regression analysis, retrodiscal tissues from the painful joints demonstrated a significantly higher density of fibroblasts, presence of narrowed and obliterated arterial lumens, and a significantly lower distribution of elastic fibers.

CONCLUSION

The results indicate that there is a difference between painful and asymptomatic joints at the microscopic level.

Age-related changes of the retrodiscal tissues in the temporomandibular joint

PURPOSE

This study compares the histologic features of the lateral capsule and lateral and central posterior disc attachment of temporomandibular joints (TMJs) in young and elderly persons.

MATERIAL AND METHODS

Samples were removed from 36 joints belonging to young persons (mean age, 30 years; age range, 16 to 39 years) and 29 joints belonging to elderly persons (mean age, 69 years; age range, 58 to 78 years). Twelve joints from elderly persons had altered disc position, whereas none of the young joints had this condition. Six-micrometer-thick sections were stained with hematoxylin-eosin and the Fränkel method (for elastic fibers). Logistic regression analysis using a likelihood-ratio test was applied for comparisons between groups and to avoid the confounding effect of differences in disc position and gender.

RESULTS

A significantly lower density of fibroblasts was observed in elderly persons in all the three areas investigated. In addition, elderly persons demonstrated a significantly lower distribution of vascular tissue and a significantly higher presence of dense connective tissue in the central third of the posterior disc attachment.

CONCLUSION

This study shows that retrodiscal tissues, which may eventually function as an articular disc during altered disc position, are susceptible to age-related connective tissue changes.

Radiographic diagnosis of temporomandibular disorders

Although many of the disorders involving the temporomandibular joint and associated structures can be diagnosed clinically on the basis of the history and physical findings, there are others that require the use of various imaging techniques to make an accurate diagnosis or to determine the extent of involvement. To take maximum advantage of the benefits of these procedures, however, it is not only important for the clinician to be able to select the correct methods, but also to understand their limitations as well as their capabilities. In this article the various techniques used for imaging the hard and soft tissues of the temporomandibular joint are reviewed and recommendations are made regarding their appropriate applications.

Current trends in temporomandibular joint imaging

Diagnostic imaging of the temporomandibular joint has undergone a revolutionary development during the last two decades. With advanced modalities we have been able to differentiate between different articular entities in patients with temporomandibular joint disorders. The purpose of this article is to review and discuss these modalities and their contribution to our present knowledge, with emphasis made on current trends in diagnostic temporomandibular joint imaging. The main section deals with diagnostic imaging of the subgroup of disorders with internal derangement caused by disk displacement including posttreatment imaging. Imaging of pathologic entities characterized by chronic inflammation such as rheumatoid arthritis are discussed in the second section. Finally, the potential of diagnostic imaging of infrequent conditions such as tumors is briefly reviewed. Magnetic resonance imaging has surpassed arthrography and computed tomography for the evaluation of most patients in these three subgroups. In patients who have various forms of disk displacements with or without accompanying bone abnormalities, a diagnostic accuracy of at least 90% may be achieved by oblique sagittal and coronal magnetic resonance imaging. In addition, alterations in the condylar marrow may be detected. T2-weighted magnetic resonance imaging can make a significant diagnostic contribution by demonstrating inflammatory reactions such as joint effusion and marrow edema. In the subgroup of patients with chronic inflammatory diseases, magnetic resonance imaging may also demonstrate abnormalities not shown with other imaging modalities. Disk deformation, fragmentation, and destruction may indirectly suggest the presence of synovial proliferation/pannus formation, which in selected cases may be directly depicted with intravenous gadopentetate dimeglumine. For more detailed evaluation of the bone condition and of soft tissue calcifications in joints with inflammatory diseases, tumors, or other disorders, computed tomography is the preferable imaging modality.

Steepness of the articular eminence in the temporomandibular joint. Tomographic comparison between asymptomatic volunteers with normal disk position and patients with disk displacement

OBJECTIVE

A steep articular eminence has been proposed as one etiologic factor for the development of TMJ disk displacement. The purpose of this study was to determine the steepness of the articular eminence in asymptomatic volunteers with superior disk position and to compare it with the articular eminence in patients with internal derangement.

STUDY DESIGN

We investigated 34 asymptomatic volunteers and 71 patients. The steepness of the articular eminence was determined on sagittally corrected tomograms, and disk position was diagnosed by dual space arthrotomography.

RESULTS

The results showed that the articular eminence was on the average steeper in the asymptomatic volunteers in the lateral (64.9 degrees), central (64.4 degrees), and medial (65.4 degrees) sections of the joint than in the patients (56.1 degrees, 60.2 degrees, 58.9 degrees, respectively). When the comparison of the steepness of the eminence was based on the presence or absence of osseous changes in the form of remodeling or osteoarthrosis, no difference was found between the asymptomatic volunteers and the patients with disk displacement but without such changes. The largest difference in the steepness of the eminence was found between the persons with osseous changes and those without.

CONCLUSION

These findings contradict earlier studies that have indicated a steep articular eminence to be one etiologic factor for the development of disk displacement. The results of this study showed that the steepness of the articular eminence is decreased in the patients as a result of remodeling or degenerative changes of the bone that are a result of the internal derangement.

Morphologic changes in the temporomandibular joint in different age groups. An autopsy investigation

Comparisons among several temporomandibular joint autopsy studies indicate that the frequency of arthrosis and disk displacement is higher in elderly persons. The aim of this study was to investigate type, frequency, and location of morphologic changes in temporomandibular joint autopsy specimens divided into two groups according to age and to determine the differences between the two groups. For this purpose 68 temporomandibular joints were removed from 37 persons at autopsy. Group I (young) consisted of 36 specimens belonging to 19 persons with a mean age of 30 years (range, 16 to 39 years). Group II (elderly) consisted of 32 specimens from persons with a mean age of 68 years (range, 55 to 78 years). Significant differences between the two groups were observed with respect to several of the morphologic changes that were evaluated. The results of this study suggest that the frequency of morphologic changes such as deviation in form, arthrosis, perforations, disk displacement, disk deformation, and adhesions is higher in the temporomandibular joints of elderly persons.