Temporomandibular Joint Imaging Research Articles

Analysis of magnetic resonance imaging characteristics and pain in temporomandibular joints with and without degenerative changes of the condyle

The aim of this study was to investigate temporomandibular joint (TMJ) pain and magnetic resonance imaging characteristics in 104 TMJs with and 58 without degenerative changes of the condyle, such as osteophytes, erosion, avascular necrosis, subcondral cyst and intra-articular loose bodies. TMJ images were also assessed for flattening, retropositioning and hypomobility of condyle and disc displacement. Comparison of the TMJ side-related data showed a significant relationship between disc displacement without reduction (DDwoR) and the presence of degenerative bony changes ( p = 0.00). Flattening, retropositioning and hypomobility of condyle showed no significant difference in relation to the presence or absence of degenerative bony changes. Retropositioning of the condyle was significantly associated to disc displacement with reduction (DDwR) ( p = 0.00), while condylar hypomobility was significantly more frequent in TMJ with DDwoR ( p < 0.05). Independent of the presence or type of DD, TMJ pain was more frequent in the presence of degenerative bony changes. When considering only DDwR, TMJ pain was significantly associated to a degenerative condition ( p = 0.03). When there were no degenerative bony changes, TMJ pain was significantly more frequent in DDwoR ( p = 0.04). Despite the present findings, the absence of symptoms in some patients with condylar bony changes suggests that the diagnosis of osteoarthritis should be established by evaluation of magnetic resonance images in association with clinical examination.

Role of different imaging modalities in assessment of temporomandibular joint erosions and osteophytes: a systematic review

To evaluate the ability of different diagnostic imaging techniques for diagnosing the presence of erosions and osteophytes in the temporomandibular joint (TMJ). A systematic search of PubMed, Medline, all Evidence Based Medicine (EBM) reviews, Embase, Web of Sciences and Lilacs identified nine articles that met the selection criteria: some type of TMJ diagnostic imaging, data from autopsy or dry skull TMJs as gold standard, absence of diagnosed systemic arthritis and evaluation of the presence of erosions and/or osteophytes. A hand search of the references of the selected articles was also performed. Selected studies evaluated panoramic imaging (unenhanced and colour-enhanced digital subtraction panoramic imaging), axially corrected sagittal tomography, axially corrected frontal tomography, sagittal MRI, CT, high-resolution ultrasound and cone beam CT (CBCT). Axially corrected sagittal tomography is currently the imaging modality of choice for diagnosing erosions and osteophytes in the TMJ. CT does not seem to add any significant information to what is obtained from axially corrected sagittal tomography. CBCT might prove to be a cost- and radiation dose-effective alternative to axially corrected sagittal tomography. Combining different radiographic techniques is likely to be more accurate in diagnosing erosions and osteophytes in the TMJ than using a single imaging modality. Diagnostic studies that simultaneously evaluate all of the available TMJ imaging technologies are needed.

Evaluation of digital linear tomosynthesis imaging of the temporomandibular joint: initial clinical experience and evaluation

This study was performed to evaluate the potential clinical application of digital linear tomosynthesis systems in imaging of the temporomandibular joint (TMJ). A volumetric X-ray digital linear tomosynthesis system (Sonialvision Safire; Shimadzu Co., Kyoto, Japan) was used for TMJ imaging. Images were reconstructed with a modified three-dimensional (3D) filtered backprojection (FBP) algorithm on this device. Our modified 3D FBP was first evaluated using simulated images of numerical phantoms. Next, patients with TMJ disease were evaluated with X-ray digital linear tomosynthesis. The results indicate that numerical phantom and TMJ visualization can be improved by the ability to produce sectional images that blur overlying structures and yield 3D information. The flexibility of digital linear tomosynthesis, as well as the fact that through an appropriate choice of modified FBP algorithms it can suppress streak artefacts, makes it a potentially appropriate approach for evaluating the TMJ. The utility of digital linear tomosynthesis for the evaluation of TMJ was demonstrated. Digital linear tomosynthesis may be considered as the imaging technique of choice in the investigation of bony changes of the TMJ.

METHODS OF IMAGING IN THE DIAGNOSIS OF TEMPOROMANDIBULAR JOINT DISORDERS

Different methods of temporomandibular joint imaging are presented and discussed. Research reports published from 1979 to 2002 have been evaluated. The aim of this paper is to summarize the main findings from research. Basic X-ray examination is the most readily available method of imaging which usually does not have any contraindication. The use of computer tomography offers all advantages of tomographic scanning in different layers and projections, imaging soft tissues close to the joint and the possibility of "3D" reconstruction of bone structures. In case of joint dysfunctions and internal joint derangement, it is more preferable to use nuclear magnetic resonance for the depiction of the joint structures. To make a diagnosis more efficient, miniinvasive diagnostic methods are becoming necessary. Arthroscopy allows direct visual control of the joint space with the possibility of therapeutic help in cases when conservative treatment has failed. Ultrasonography, as a completely non-invasive procedure, is applied even in diagnosing functional temporomandibular defects. In these cases the diagnostic value of ultrasonography is almost comparable with this of nuclear magnetic resonance. So it is possible that, together with the improvement of the equipment, development of the diagnostic methods used during the treatment of temporomandibular joint defects could continue in this direction.

The 3DX multi image micro-CT device in clinical dental practice

To evaluate the usefulness of 3DX multi-image micro-CT device in clinical dental practice. Images of 198 examinations performed with a 3DX device during a 6 month period in a private dental practice were evaluated retrospectively for the benefit of additional information compared with panoramic or intraoral radiographs. The main indication for the use of 3DX micro-CT was planning of dental implant placement in 49% of the examinations. Diagnosis or exclusion of dental infection or peri-implantitis represented 28% of the examinations and tooth, root or foreign body localization represented 13%. Temporomandibular joint (TMJ) imaging and cyst or tumour diagnosis represented 7.5% and 2.5% of the examinations, respectively. In implant planning and tooth, root or foreign body localization examinations, the required information was obtained in every case except three implant planning examinations, in which the exact measurements were hampered by artefacts caused by root fillings and retrograde fillings or metal posts. When compared with conventional radiography, additional radiographic information was obtained in 51% of the micro-CT examinations performed to confirm or exclude dental infection or peri-implantitis. Micro-CT also showed the bone structure of TMJs precisely. The 3DX micro-CT device visualizes bony anatomical structures precisely, which makes it a reliable tool for, for example, planning of implant treatment. The device is highly suitable for diagnosing dental infections. Dental restorations may cause disturbing artefacts and in 4.5% of the examinations the small imaging area resulted in re-examination.

Discrimination of internal derangement of temporomandibular joint by lateral cephalometric analysis

The purposes of this study were to analyze the progress of internal derangement (ID) of the temporomandibular joint (TMJ) and to find critical yardsticks that can be used during lateral cephalometric analysis to identify subjects with potential ID. The sample consisted of 134 women whose primary complaints were malocclusions. They were divided into 5 groups based on the results of magnetic resonance imaging of bilateral TMJs: bilateral normal disc position, unilateral disc displacement with reduction (DDR) and contralateral normal disc position, bilateral DDR, unilateral DDR and contralateral disc displacement without reduction (DDNR), and bilateral DDNR. Thirty-six cephalometric variables from their lateral cephalograms were analyzed with 1-way ANOVA and discriminant analysis to determine the key factors in identifying subjects with TMJ ID. Backward positioning of the mandible, clockwise rotation of the mandible, proclination of the mandibular incisors, and increase in overjet intensified gradually with the progression of TMJ ID, and the subjects with bilateral DDNR showed the greatest changes in dentofacial morphology. Stepwise variable selection in discriminant analysis identified the following 2 variables: mandibular incisor to Frankfort horizontal plane angle and overjet. Discriminant analysis resulted in the correct classification of 79.1% of the subjects and showed that those with smaller mandibular incisor to Frankfort horizontal plane angles and larger overjets had high possibilities of TMJ ID. This study suggests that some cephalometric variables can be used as an auxiliary diagnostic tool to help identify patients with potential TMJ ID.

The value of three-dimensional computed tomography in diagnosis and management of Jacob's disease

This study reports a case of Jacob's disease characterized with limited mouth opening due to bilateral coronoid hyperplasia forming pseudojoints with zygomatic arches. Magnetic resonance (MR) examination of temporomandibular joint (TMJ) is usually the imaging method chosen in patients with such symptoms. However, the coronoid processes can not be displayed because they are not included in field of view in MR imaging of TMJ. For that reason, these patients may be treated for a misdiagnosis of TMJ disorders. In this study, the aetiology and diagnostic methods of Jacob's disease, the pre-operative/post-operative role of three-dimensional computed tomography and some measurements used in diagnosis were evaluated.

Two- and three-dimensional orthodontic imaging using limited cone beam-computed tomography.

Considerable progress has been made in diagnostic, medical imaging devices such as computed tomography (CT). However, these devices are not used routinely in dentistry and orthodontics because of high cost, large space requirements and the high amount of radiation involved. A device using computed tomography technology has been developed for dental use called a limited cone beam dental compact-CT (3DX). The aim of this article is to demonstrate the usefulness of 3DX imaging for orthodontic diagnosis and treatment planning. We present three cases: (1) one case shows delayed eruption of the upper left second premolar, (2) the second case shows severe impaction of a maxillary second bicuspid; and (3) the third case shows temporomandibular joint disorder (TMD). In the tooth impaction cases, the CT images provided more precise information than conventional radiographic images such as improved observation of the long axis of the tooth, root condition, and overlap with bone. In the TMD case, clear and detailed temporomandibular joint images were observed and pre- and posttreatment condylar positions were easily compared. We conclude that 3DX images provide useful information for orthodontic diagnosis and treatment planning.

Relationship between internal derangement of the temporomandibular joint and dentofacial morphology in women with anterior open bite

Anterior open bite is known to be associated with internal derangement of the temporomandibular joint (TMJ). This study examined the relationships between internal derangement and dentofacial morphology in women with anterior open bite. Fifty-one women with anterior open bite were enrolled in this study. The sample was divided into 3 groups based on magnetic resonance imaging of bilateral TMJs: normal disk position, disk displacement with reduction, and disk displacement without reduction. One-way analysis of variance was used to compare the 3 groups with respect to the cephalometric variables, and Duncan's multiple comparisons were performed at the 95% confidence level to identify the differences among the 3 groups. Internal derangement of the TMJ was much more prevalent in subjects with a more posteriorly rotated mandibular ramus, a smaller mandible, and a greater tendency for a skeletal Class II pattern, although all subjects had an anterior open bite. These patterns were more severe as the internal derangement progressed to disk displacement without reduction. Some cephalometric characteristics, such as a decrease in posterior facial height, decrease in ramus height, and backward rotation and retruded position of the mandible, are associated with TMJ internal derangement in women with anterior open bite.

Treatment of severe temporomandibular joint clicking with botulinum toxin in the lateral pterygoid muscle in two cases of anterior disc displacement

A novel treatment procedure is introduced for severe clicking of the temporomandibular joint (TMJ) associated with anterior disc displacement (ADD), using injections with botulinum toxin (BTX-A) in the lateral pterygoid muscle (LP). It has been suggested that ADD may be caused, precipitated, or maintained by LP activity, but the role of the LP in the dynamics of the TMJ clicking is uncertain. The case report includes 2 women, followed with clinical examinations, TMJ imaging, and electromyography (EMG), in whom local anesthetics in the LP could abolish the clicking for several days. BTX-A block of the LP (30 U Botox, given twice under EMG guidance with 6-month interval) temporarily reduced the action of the muscle, but the clicking was permanently eliminated and did not return during the observation period of 1 year, and a small but distinctive positional improvement in the disc-condyle relationship was obtained. However, the precise mechanisms behind the favourable treatment outcome are unclear.

About the difficulty in interpreting ultrasonographic images of temporomandibular joint: reply

About the difficulty in interpreting ultrasonographic images of temporomandibular joint: reply

The 3DX multi-image micro-CT device in clinical dental practice

Objectives: To evaluate the usefulness of 3DX multi-image micro-CT device in clinical dental practice. Methods: Images of 198 examinations performed with a 3DX device during a 6 month period in a private dental practice were evaluated retrospectively for the benefit of additional information compared with panoramic or intraoral radiographs. Results: The main indication for the use of 3DX micro-CT was planning of dental implant placement in 49% of the examinations. Diagnosis or exclusion of dental infection or peri-implantitis represented 28% of the examinations and tooth, root or foreign body localization represented 13%. Temporomandibular joint (TMJ) imaging and cyst or tumour diagnosis represented 7.5% and 2.5% of the examinations, respectively. In implant planning and tooth, root or foreign body localization examinations, the required information was obtained in every case except three implant planning examinations, in which the exact measurements were hampered by artefacts caused by root fillings and retrograde fillings or metal posts. When compared with conventional radiography, additional radiographic information was obtained in 51% of the micro-CT examinations performed to confirm or exclude dental infection or peri-implantitis. Micro-CT also showed the bone structure of TMJs precisely. Conclusions: The 3DX micro-CT device visualizes bony anatomical structures precisely, which makes it a reliable tool for, for example, planning of implant treatment. The device is highly suitable for diagnosing dental infections. Dental restorations may cause disturbing artefacts and in 4.5% of the examinations the small imaging area resulted in re-examination. Dentomaxillofacial Radiology (2007) 36, 80–85. doi: 10.1259/dmfr/30358216

Condylar shape analysis using panoramic radiography units and conventional tomography

The objective of this study was to compare condyle shape between lateral temporomandibular joint (TMJ) images from axially corrected tomography and 3 panoramic radiography units with TMJ-specific programs. The TMJ from a single dry human skull was imaged with multidirectional tomography and the following 3 panoramic radiography units: Instrumentarium OP 100, Planmeca PM 2002 CC Proline, and Soredex Orthophos DS. A curve-fitting procedure (spline curves) was used to mathematically describe condyle outlines. One sample t tests were used to compare panoramic images against the tomograms (gold standard). A significant difference (P < .05) in condyle shape was found between TMJ tomography images and each of the 3 panoramic images. Images from the PM 2002 CC Proline demonstrated the smallest shape difference (13.4%), followed by the OP 100 (17.5%) and the Orthophos DS (24.8%). If panoramic radiography is to be used for the initial radiographic examination of the TMJ, practitioners should be aware of the potential for shape distortion of the condyle.

Magnetic resonance imaging of the temporomandibular joint: a study of inter- and intraobserver agreement

Objective The purpose of this study was to estimate the inter- and intraobserver agreement for interpreting magnetic resonance (MR) images of the temporomandibular joint (TMJ).

Temporomandibular joint: a methodology of magnetic resonance imaging 3-D reconstruction

Objective The aim of this study was to develop a new method for the 3-dimensional reconstruction of the temporomandibular joint (TMJ) images by means of magnetic resonance imaging (MRI). In a preliminary study, this modality of 3-D representation was tested to evaluate the joint motion. Study design Sagittal MRI slices were obtained from a healthy subject. Acquisitions were realized by a spin-echo sequence, with a proton-density weighting and a 2-mm slice thickness. A 3-D reconstruction of the TMJ images was performed. Results Three-dimensional representations of the temporomandibular joint were obtained. The depiction of the principal anatomical elements of this joint was realized. A study of TMJ dynamics was also carried out. In this case, movements of the right and left disks and condyles were measured. Conclusion This 3-D reconstruction methodology allowed a more understandable anatomical description than 2-D images of the TMJ and offered possibilities for joint functional analysis.

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.

A comparative assessment of mandibular condylar position in patients with anterior disc displacement of the temporomandibular joint

Purpose: The purpose of this study was to determine whether the position of the mandibular condyle in patients with anterior disc displacement (ADD) is different from that of a control group with normal joints using a novel method to quantify the irregular shape of the temporomandibular joint (TMJ). Materials and Methods: Twenty-six magnetic resonance images of TMJs with ADD were evaluated and compared with 14 normal joints. The position of the condyle was determined by using 2 different methods: 1) measuring the horizontal and vertical normalized distances in millimeters between the geometric centers of the glenoid fossa and the condyle and 2) calculating the anteroposterior joint space ratio. Results: Using the first method, the horizontal distance between the centers of the condyle and the glenoid fossa was 14.0 ± 11.1 in the ADD group and 5.3 ± 10.9 in the control group ( P < .001). The vertical distance was 64.7 ± 22.7 in the ADD group and 68.3 ± 32.9 in the control group ( P = .015). The ratio of the horizontal and the vertical condylar displacement in the ADD group was 2.4. Using the second method, the anteroposterior joint space ratios in the ADD group and in the control group were 1.7 ± 0.5 and 1.2 ± 0.4, respectively ( P = .001). Conclusion: This study found that condyles of patients with ADD were situated more posterior and superior in the fossa than those in the control group. Moreover, in the ADD group, the posterior condylar displacement was noted to be 2.4 times greater than the superior condylar displacement.

Solid-state temporomandibular joint imaging: accuracy in detecting osseous changes of degenerative joint disease and determining condylar spatial relations

The purpose of this study was to evaluate the off-label use of an intraoral charge-coupled device (CCD) for extraoral transcranial radiography of the temporomandibular joint. Corrected linear tomograms and transcranial images made with conventional screen–film combinations and a CCD detector were compared with sectioned cadaver specimens. Radiation dosage, qualitative assessment of condylar degenerative features, and condylar position within the glenoid fossa of the 3 modalities were assessed and compared. The CCD method required special adjustments to achieve adequate quality, and it involved greater exposure than the other methods. This use of this intraoral system for extraoral imaging cannot now be recommended, but future refinements might make it more viable.

Superconducting RF coils for clinical MR imaging at low field 1

Rationale and Objectives. A number of recent reports in the MRI literature have established that substantial signal-to-noise ratio (SNR) gains can be achieved with small samples or low resonance frequencies, through the use of high-quality factor high-temperature superconducting (HTS) RF receive coils. We show the application of HTS coils to the imaging of human subjects with improved SNR compared with copper coils. Materials and Methods. HTS coils were constructed from 7.62-cm YBa 2Cur 3O 7-δ thin films on LaAlO 3 substrate and cooled in a liquid nitrogen cryostat. Human and phantom images were acquired on a 0.2-T scanner. The SNR improvements compared with equivalent-sized copper coils are reported. Results. SNR gains of 2.8-fold and 1.4-fold were observed in images of a phantom acquired with an HTS coil versus a room temperature copper coil and a liquid nitrogen-cooled copper coil, respectively. Preliminary results suggest higher image quality can be obtained in vivo with an HTS coil compared with copper coil imaging. Images of human orbit, brain, temporomandibular joint, and wrist are presented. Conclusion. The experimental results show that benefits can be expected from application of HTS surface coils in human MR imaging with low-field scanners. These potential benefits justify the continued development of practical HTS coil imaging systems despite the considerable technical difficulties involved in cryostat and coil design.

Advances in TMJ imaging

The oral and maxillofacial surgeon often plays a primary role in the diagnosis and management of patients with temporomandibular joint (TMJ) dysfunction. With several diseases affecting the joint and several imaging modalities available, the surgeon must decide which modalities are best for each individual patient.