Frequency of temporomandibular joint osteoarthritis and related symptoms in a hand osteoarthritis cohort.

OBJECTIVE: The prevalence of osteoarthritis (OA) in the temporomandibular joints (TMJs) in hand OA patients is largely unknown. Our aims were to explore (1) The frequency of TMJ-related symptoms and clinical findings; (2) The TMJ OA frequency defined by cone beam computed tomography (CBCT); and (3) The relationship between TMJ-related symptoms/clinical findings and CBCT-defined TMJ OA, in a hand OA cohort. METHODS: We calculated the frequencies of TMJ-related symptoms, clinical findings and diagnosis of TMJ OA by CBCT and clinical examination in 54 patients from the Oslo hand OA cohort (88% women, mean (range) age 71 (61-83) years). Participants with and without CBCT-defined TMJ OA were compared for differences in proportions (95% confidence interval (CI)) of symptoms and clinical findings. Sensitivity and specificity of the clinical TMJ OA diagnosis were calculated using CBCT as reference. RESULTS: Self-reported symptoms and clinical findings were found in 24 (44%) and 50 (93%) individuals (93%), respectively, whereas 7 (13%) had sought healthcare. Individuals with CBCT-defined TMJ OA (n = 36, 67%) reported statistically significantly more pain at mouth opening (22%, 95% CI 4-40%), clicking (33%, 95% CI 14-52%) and crepitus (25%, 95% CI 4-46%). By clinical examination, only crepitus was more common in TMJ OA (33%, 95% CI 29-77%). Clinical diagnosis demonstrated low sensitivity (0.42) and high specificity (0.93). CONCLUSIONS: CBCT-defined TMJ OA was common in hand OA patients, suggesting that TMJ OA may be part of generalized OA. Few had sought healthcare, despite high burden of TMJ-related symptoms/findings. Clinical examination underestimated TMJ OA frequency.

Temporomandibular joint diagnostics using CBCT.

The present review will give an update on temporomandibular joint (TMJ) imaging using CBCT. It will focus on diagnostic accuracy and the value of CBCT compared with other imaging modalities for the evaluation of TMJs in different categories of patients; osteoarthritis (OA), juvenile OA, rheumatoid arthritis and related joint diseases, juvenile idiopathic arthritis and other intra-articular conditions. Finally, sections on other aspects of CBCT research related to the TMJ, clinical decision-making and concluding remarks are added. CBCT has emerged as a cost- and dose-effective imaging modality for the diagnostic assessment of a variety of TMJ conditions. The imaging modality has been found to be superior to conventional radiographical examinations as well as MRI in assessment of the TMJ. However, it should be emphasized that the diagnostic information obtained is limited to the morphology of the osseous joint components, cortical bone integrity and subcortical bone destruction/production. For evaluation of soft-tissue abnormalities, MRI is mandatory. There is an obvious need for research on the impact of CBCT examinations on patient outcome.

Cherubism: panoramic and CT features in adults.

OBJECTIVES: To describe the panoramic radiographic and CT features of cherubism in an unselected series of 15 adults. METHODS: In this cross-sectional study, 15 individuals aged 29-84 years with familial non-syndromal molecularly confirmed cherubism were examined with panoramic radiography and CT. Bone abnormalities were analysed and described. RESULTS: 11 (73%) of the 15 adults had mandibular abnormalities. These abnormalities ranged from subtly detectable to severe, and were less prevalent and expansive but could be rather similar to the characteristic image features in children. Unilocular radiolucencies were more common than multilocular radiolucencies, and a specific feature of these abnormalities was that they were exclusively found in the anterior mandible. CONCLUSIONS: The radiographic and CT abnormalities of cherubism in adults were frequent and extremely heterogeneous, with some distinct features.

Craniofacial growth disturbance is related to temporomandibular joint abnormality in patients with juvenile idiopathic arthritis, but normal facial profile was also found at the 27-year follow-up.

OBJECTIVES: To assess the long-term outcome of craniofacial morphology related to disease variables and temporomandibular joint (TMJ) involvement as demonstrated with computed tomography (CT) and magnetic resonance imaging (MRI) in adult patients with juvenile idiopathic arthritis (JIA). METHODS: Sixty of 103 patients participated in a re-examination on average 27 years after baseline. Craniofacial morphology, with emphasis on size and position of the mandible, was assessed in lateral cephalographic images and related to disease variables and TMJ involvement by CT and MRI. Definitions of craniofacial growth disturbances were based on measurements outside 2 SD from the mean of healthy adult controls. RESULTS: Sagittal craniofacial growth disturbances were found in 57% and micrognathia in 27% of the 60 patients. Of those with JIA TMJ involvement, 70% had some form of growth disturbance. Micrognathia occurred only in patients with bilateral TMJ involvement. The bilateral TMJ group had significantly different craniofacial morphology than healthy controls and patients without TMJ involvement. Growth disturbances and TMJ involvement were present in all subtypes of JIA, except for one subtype comprising one patient. Patients with growth disturbances had more severe disease than patients with normal craniofacial growth, regarding both present and previous disease activity. Unexpectedly, half of the patients without craniofacial growth disturbances also had TMJ involvement, many from before the age of 12. CONCLUSIONS: Craniofacial growth disturbances were found to be frequent in adult JIA patients, especially in those with bilateral TMJ involvement. However, growth disturbances did not always follow TMJ involvement, not even when affected early.

Osseous abnormalities of the mandibular condyle: diagnostic reliability of cone beam computed tomography compared with helical computed tomography based on an autopsy material.

OBJECTIVES: We compared the diagnostic reliability of cone beam computed tomography (3DX) and helical computed tomography (helical CT) for the detection of osseous abnormalities of the mandibular condyle, using macroscopic observations as the gold standard. METHODS: Twenty-one temporomandibular joint autopsy specimens underwent imaging with 3DX and helical CT. The specimens were macroscopically evaluated for cortical erosion or osteophytosis and sclerosis. The images were independently assessed for the same osseous abnormalities. Observations with the two imaging modalities were compared with the macroscopic observations using the McNemar test. RESULTS: According to the macroscopic observations, 10 of the 21 mandibular condyles and one fossa showed osseous abnormalities. 3DX detected abnormalities in eight of these condyles and helical CT identified abnormalities in seven, giving a sensitivity of 0.80 for 3DX and 0.70 for helical CT. The specificity of the condyle assessment was 1.0 for both 3DX and helical CT and hence, the accuracy was 0.90 and 0.86, respectively. No significant differences were detected between the 3DX and helical CT for assessment of osseous abnormalities of the mandibular condyle (P=0.286). CONCLUSIONS: The cone beam CT equipment 3DX is a dose-effective and a cost-effective alternative to helical CT for the diagnostic evaluation of osseous abnormalities of the mandibular condyle.

Comparison of standard and task-specific enhancement of Digora storage phosphor images for approximal caries diagnosis.

OBJECTIVES: To compare approximal caries detection on Digora storage phosphor images pre-enhanced with the automatic "caries-specific Oslo enhancement procedure" ("Oslo-enhanced" method) and storage phosphor images individually enhanced by observers particularly experienced in digital imaging using standard brightness and contrast functions of the Digora system ("Digora-enhanced" method). METHODS: Seven staff members from four oral radiology departments rated 240 approximal surfaces for caries with regard to lesion depth in the inner and outer half of the enamel and dentine, using a 5-point confidence scale. The observations were validated histologically. A receiver operating characteristic (ROC) analysis and an analysis of variance with three dependent variables (observer confidence, observer signed error and observer absolute error) were performed. RESULTS: The most evident difference between the methods as elucidated by the ROC analysis was the highly significant smaller interobserver and intraobserver variance with the Oslo-enhanced method for all but one observer. The methods were not different with regard to average diagnostic accuracy (A(z) values) as tested with paired t-tests, and there was no correlation between A(z) across methods. The method and lesion main effects, as well as the lesion by method interaction effect, were multivariately significant (P<0.001) in favour of the Oslo-enhanced method. On a univariate level, the method main effect was not significant for the absolute observer error (P=0.330). All other univariate effects were significant (P<0.001). CONCLUSIONS: The accuracy of approximal caries detection with Digora storage phosphor images pre-enhanced and images individually enhanced was similar, but interobserver and intraobserver variability improved with the Oslo-enhanced method. Since image manipulation is not performed with the Oslo-enhanced method, the increased speed of the diagnostic procedure combined with the improved observer variability would probably be even more pronounced for the general dental practitioner.

Recurrent conventional cemento-ossifying fibroma of the mandible.

Cemento-ossifying fibromas are slow growing, benign lesions. Recurrence is considered rare. A mandibular periapical radiolucent lesion in a 30-year-old female was diagnosed histologically as a cemento-ossifying fibroma and excised. A recurrence was found 2 years and 6 months postoperatively. CT demonstrated that the recurrent lesion was larger than indicated by conventional radiography.

MR grading of temporomandibular joint fluid: association with disk displacement categories, condyle marrow abnormalities and pain.

The purpose of this study was to investigate temporomandibular joint (TMJ) effusion on magnetic resonance (MR) images, and its association with specific categories of disk displacement, bone marrow abnormalities and pain. From a series of 523 consecutive TMJ MR imaging studies of patients referred to imaging because of pain and dysfunction, those with TMJ effusion, defined as an amount of fluid that exceeded the maximum amount seen in a control group of asymptomatic volunteers, were analysed. The selected patients were reassessed and the amount of TMJ fluid was graded bilaterally according to a set of reference films. Other parameters recorded included disk displacement categories and condyle marrow abnormalities. Pain self-records were obtained from the patients immediately before MR imaging. The association between the recorded parameters and TMJ pain was analysed with t-tests and regression analysis. Of the 523 patients, 70 (13%) had TMJ effusion, which was unilateral in 61%. Only 9% of the 70 patients had effusion bilaterally, whereas bilateral disk displacement was found in 80%. In the 76 joints with effusion, 83% showed two specific categories of disk displacement at closed mouth. Condyle marrow abnormalities were found in 31% of the 70 patients, mostly on one side, and in 24% of the 76 joints. An in-patient regression analysis of the side difference in TMJ pain showed that effusion and condyle marrow abnormalities were significant pain-increasing factors. In conclusion, patients with TMJ effusion represent a subgroup with pain and dysfunction with more severe intra-articular pathology than those with disk displacement but no other joint abnormalities.

MR evidence of temporomandibular joint fluid and condyle marrow alterations: occurrence in asymptomatic volunteers and symptomatic patients.

The purpose of this study was to estimate the frequency and amount of temporomandibular joint (TMJ) fluid, as well as the frequency and type of condyle marrow alterations in asymptomatic volunteers and compare to patients with TMJ pain and dysfunction. Proton-density and T2 weighted magnetic resonance (MR) images of the TMJs of 62 asymptomatic volunteers and 58 symptomatic patients were analysed for fluid and condyle marrow alterations as well as disk position. The amount of fluid (increased T2 signal) was characterized as none, minimal, moderate or marked and related to the disk position. The differentiation between moderate and marked fluid was based on the maximum amount of fluid seen in the volunteers; more than this amount was categorized as marked fluid. The marrow of the mandibular condyle was categorized as normal, edema (increased T2 signal) or sclerosis (decreased proton-density and T2 signal) and related to fluid and disk position. In the 62 asymptomatic volunteers, 50 (81%) had none or minimal and 12 (19%) had moderate TMJ fluid. In the 58 symptomatic patients, 40 (69%) had none or minimal and 18 (31%) had moderate or marked fluid. Both in volunteers and patients, moderate fluid could be seen in joints with normal disk position, but was significantly associated with disk displacement. In the 62 volunteers, no signal abnormalities in the condyle marrow were found. In the 58 patients, six (10%) had abnormal bone marrow. These six patients had disk displacement and two had moderate or marked fluid. Marked fluid and condyle marrow abnormalities were therefore not encountered in any of the asymptomatic volunteers but in about 10% of the patients.

Osteoradionecrosis of the mandible. Comparison of the effects of external beam irradiation and brachytherapy.

OBJECTIVE: To compare the difference in location and severity of osteoradionecrosis (ORN) of the mandible following either external beam irradiation alone or combined with brachytherapy in the management of orofacial cancer. METHODS: CT was used to evaluate ORN in relation to the radiation source and field and the site of malignancy in 31 patients with orofacial carcinomas. Twenty-three patients received combined radiotherapy and brachytherapy and eight patients only external radiotherapy. The radiation dose distribution to the mandible was calculated retrospectively. RESULTS: In the combined radiotherapy group all patients had ORN of the lingual cortex, mostly adjacent to the position of previous iridium implants. Lingual defects were also found in the contralateral mandible in 35% of patients. Defects in the buccal cortex were seen in 30%. In the external radiotherapy group, ORN was found in both buccal and lingual cortices and 50% also in the contralateral mandible. When brachytherapy with iridium implants was used the dose to the buccal cortex was about one-third of that to the lingual cortex. There was no dose gradient between the cortices using external beam irradiation alone. CONCLUSIONS: Evidence of ORN was found in both groups of irradiation regimens. Thus, the entire irradiated mandible should be considered as a compromised tissue at risk of ORN.

Ortho cubic super-high resolution computed tomography: a new radiographic technique with application to the temporomandibular joint.

OBJECTIVE: The purpose of this study was to present a newly developed ortho cubic super-high resolution computerized radiographic technique (Ortho-CT) and its application to the temporomandibular joint. METHOD AND PATIENTS: A prototype was assembled on a Scanora (Soredex Findent Co) with the use of a 4-inch image intensifier instead of film. Data were collected from a single 360 degrees scan and a cylinder 32 mm in height and 38 mm in diameter. Images were reconstructed with a software program on a personal computer. Imaging data consisted of 240 (height) x 280 (diameter) cubic voxels, each with a dimension of 0.136 mm. With this small voxel size, the image resolution was high and was the same in any direction. Three patients with temporomandibular joint disease (trauma, pain and dysfunction, fibroosseous ankylosis) were evaluated with Ortho-CT, and the images were compared to routine radiographic films. CONCLUSION: Preliminary clinical experience with Ortho-CT demonstrates subjectively superior image quality compared to panoramic and conventional tomographic images. The images were similar to conventional computed tomography, but this new radiographic technique is less expensive, takes less space, and gives a lesser patient dose.

Temporomandibular joint disk displacement: comparison in asymptomatic volunteers and patients.

PURPOSE: To compare the prevalence and type of temporomandibular joint (TMJ) disk displacement in asymptomatic volunteers with those in patients. MATERIALS AND METHODS: Bilateral oblique sagittal and oblique coronal intermediate-weighted magnetic resonance (MR) images of the TMJs in 58 patients with pain and dysfunction were analyzed and compared with corresponding MR images of 62 asymptomatic volunteers. RESULTS: Forty-five (78%) of 58 patients had disk displacement compared with 22 (35%) of 62 asymptomatic volunteers. Complete disk displacement was found in 46 (40%) of 115 joints in patients compared with three (2.4%) of 124 joints in asymptomatic volunteers, whereas partial disk displacement occurred in 26 (22.6%) and 27 (21.8%) joints, respectively. Two types of complete disk displacement, anterolateral and anterior, occurred frequently in patients, seldom in volunteers. Only minor differences were found between other types of disk displacement when prevalence in patients was compared with that of volunteers. The disk reduced to a normal position on open-mouth images in all joints in the volunteers compared with 76% of the joints in patients. CONCLUSION: TMJ disk displacement was less prevalent and was of a different type in asymptomatic volunteers compared with patients with pain and dysfunction.

Thickening of the glenoid fossa in osteoarthritis of the temporomandibular joint. An autopsy study.

OBJECTIVE: To evaluate the thickness of the roof of the glenoid fossa of the temporomandibular joint (TMJ) in relationship to the stage of internal derangement from autopsy material. MATERIAL AND METHODS: The minimum thickness of the roof of the glenoid fossa was measured with a caliper in 61 TMJ autopsy specimens. Based on macroscopic examination the joints were categorized as normal (30 joints), disk displacement (eight joints), disk displacement with osteoarthritis (12 joints) and osteoarthritis with perforation of the disk or posterior attachment (11 joints). The relationship between thickness of roof of the glenoid fossa and status of the joint was analysed. RESULTS: The roof of the glenoid fossa was on the average 0.6 mm in normal joints, 1.1 mm in joints both with disk displacement and disk displacement with osteoarthritis and 2.6 mm in joints with osteoarthritis and perforation. The difference between the normal joints and those with perforation was significant (P<0.01). CONCLUSION: Progressive remodeling with thickening of the roof of the glenoid fossa seems to be associated with perforation of the disk or posterior attachment.

Approximal caries depth assessment with storage phosphor versus film radiography. Evaluation of the caries-specific Oslo enhancement procedure.

OBJECTIVES: To study whether caries-specific enhancement of storage phosphor images might improve the observer performance of approximal caries depth assessments compared with film radiography. MATERIALS AND METHODS: 120 exposures were made of 120 extracted human teeth. To obtain geometrically identical images, Ektaspeed Plus films and storage phosphor plates were exposed simultaneously. The imaging plates were scanned in a Digora scanner and the files transferred to a different platform for image enhancement. Nine observers viewed films and storage phosphor images without provisions for adjustment of image intensity and contrast. For each imaging modality, 240 approximal surfaces were rated for caries on a 5-point confidence scale. Definite and probable caries lesions were also rated for lesion depth, and all ratings were compared with the histological state. Diagnostic accuracy was expressed as the area under the ROC curve (A(z) value). Paired t tests were used to compare the imaging modalities for diagnostic accuracy and F tests to compare observer variances. RESULTS: Enhanced storage phosphor images demonstrated significantly higher mean A(z) values than film (p = 0.0066). Significantly higher mean A(z) values were demonstrated in the outer half of enamel (p = 0.01), but no significant differences were found between the modalities for caries lesions penetrating beyond the outer half of the enamel. The number of correctly diagnosed true-positive surfaces with caries in outer enamel was significantly higher with storage phosphor images than with film (p = 0.00014). False-positive surfaces were most frequently registered in the outer enamel with both modalities, but in this region the number of false-positive surfaces was significantly higher with storage phosphor images than with film (p = 0.0038). Pooled sensitivity and specificity values were 0.48/0.94 and 0.61/0.86 for film and storage phosphor images, respectively. The interobserver variability was significantly lower for storage phosphor images than for film. CONCLUSION: Enhancement of storage phosphor images with a caries-specific procedure significantly improved the accuracy of caries depth assessments in the outer half of the enamel compared with film radiography and reduced observer variability.

The association of temporomandibular joint pain with abnormal bone marrow in the mandibular condyle.

PURPOSE: This study investigated the association between temporomandibular joint pain and bone marrow alterations in the mandibular condyle seen on magnetic resonance (MR) images. PATIENTS AND METHODS: The study was based on 112 temporomandibular joints in 112 patients with disc displacement without reduction. Thirty-four patients with abnormal bone marrow on MR images were compared with a control group of 78 patients with normal bone marrow. The analysis was based on proton density and T2-weighted MR images in the oblique sagittal and coronal planes. The degree of pain was correlated to the status of the bone marrow using statistical methods. RESULTS: The degree of pain in joints with abnormal bone marrow was higher than in joints with normal bone marrow signal on MR images (P = .0045). CONCLUSION: Because the stage of internal derangement was similar in both groups, more intensive pain appears to be associated with bone marrow alterations.

Dynamic MR imaging of mandibular osteoradionecrosis.

PURPOSE: Osteoradionecrotic bone has been characterised as hypovascular and metabolically inactive tissue with impaired perfusion. The present study was conducted to determine if dynamic contrast-enhanced MR imaging could provide additional information about the vascularity of radionecrotic mandibular bone. MATERIAL AND METHODS: Dynamic contrast-enhanced MR imaging was performed on 10 patients with mandibular osteoradionecrosis (ORN), and on 6 patients, irradiated for oropharyngeal tumours, without symptoms or signs of ORN. Nine patients in the ORN group received a series of 20 hyperbaric oxygen (HBO) treatments, after which the dynamic MR investigation was repeated. RESULTS AND CONCLUSION: Radiation per se did not lead to increased contrast enhancement, whereas all patients with ORN showed marked contrast enhancement of the osteoradionecrotic bone marrow. After HBO treatment, pathological contrast enhancement of the abnormal bone marrow could still be seen, but the rate of enhancement was less than before in 7 of 9 patients. Two patients had an increase in the enhancement rate. The findings suggest the existence of an increased and patent microvasculature.

Mandibular osteoradionecrosis: a comparison of computed tomography with panoramic radiography.

OBJECTIVES: To compare the value of computed tomography (CT) with panoramic radiography in the diagnosis and presurgical evaluation of mandibular osteoradionecrosis (ORN). METHODS: Retrospective study comparing the diagnostic information from CT and panoramic radiography of 33 patients with clinical symptoms of ORN. In six patients the imaging was compared macroscopically with the resected mandible. RESULTS: Both panoramic radiography and CT revealed ORN in 31 cases. In 22 the anterior-posterior extent of the lesions could be estimated with equal reliability. In six patients the lesion appeared larger on CT and in three on panoramic radiography. Mono- or bicortical destruction, central necrosis and sequestration were better visualized by CT. Comparison between the imaging findings and the surgical resection showed that CT depicted the topography of the specimen more accurately. CONCLUSIONS: CT is superior to panoramic radiography in visualizing the features of mandibular ORN and the anterior-posterior extent of the lesion.

Osteonecrosis of the temporomandibular joint: correlation of magnetic resonance imaging and histology.

PURPOSE: The aims of this study were to investigate whether osteonecrosis affects the mandibular condyle and to determine whether this condition could be diagnosed with magnetic resonance imaging (MRI). MATERIALS AND METHODS: The study was based on 50 temporomandibular joints in 44 patients in whom MRI and surgery were performed for painful internal derangements. At the time of surgery, a core biopsy specimen was obtained from the marrow of the mandibular condyles, and the histological observations were correlated to T1-(proton density) and T2-weighted MR images. RESULTS: Histological evidence of osteonecrosis was found in nine joints (18%). Bone marrow edema, which may be a precursor of osteonecrosis, was found in nine other joints. The MRI was 78% sensitive and 84% specific for the diagnosis of osteonecrosis of the mandibular condyle. However, the positive predictive value was only 54% because of a number of false-positive MRI diagnoses. CONCLUSION: Osteonecrosis can affect the mandibular condyle, and this condition can be diagnosed with MRI. A combination of edema and sclerosis of the bone marrow was the most reliable MRI sign of osteonecrosis. The cause, its clinical significance, and the need for treatment are unknown.

Osteoarthritis and abnormal bone marrow of the mandibular condyle.

OBJECTIVE: The purpose of this study was to analyze the relationship between abnormal bone marrow of the mandibular condyle and osteoarthritis. STUDY DESIGN: The relationship between abnormal bone marrow and osteoarthritis of the mandibular condyle was analyzed in magnetic resonance images of the temporomandibular joints of 74 patients. Thirty-seven patients had magnetic resonance evidence of abnormal bone marrow, and 37 control patients had magnetic resonance images with normal bone marrow. RESULTS: Fifteen of 37 patients with magnetic resonance evidence of abnormal bone marrow had no magnetic resonance evidence of osteoarthritis; the other 22 patients had both abnormal bone marrow and osteoarthritis. CONCLUSIONS: Abnormal bone marrow of the mandibular condyle can occur separately from osteoarthritis; nearly one half of the joints with magnetic resonance evidence of abnormal bone marrow did not have any evident osteoarthritis. Abnormal bone marrow may therefore initially represent a separate disease entity. Over time, secondary osteoarthritis probably develops in joints with initial bone marrow abnormalities.

Posterior disc displacement in the temporomandibular joint.

PURPOSE: The purpose of this study was to describe the imaging characteristics of posterior disc displacement of the temporomandibular joint (TMJ). MATERIALS AND METHODS: The study was based on 35 joints with posterior disc displacement and a control material of bilateral TMJ images of 62 healthy volunteers. The images were analyzed, and criteria for posterior disc displacement were developed. RESULTS: Posterior disc displacement was characterized by the disc or a major part of the disc being located posterior to the superior prominence of the condyle. Three subcategories of posterior disc displacement could be identified: a thin flat disc, a grossly posteriorly displaced disc, and a perforated disc with a portion of the disc displaced posteriorly. Posterior disc displacement was not seen in any of the asymptomatic volunteers. CONCLUSION: Posterior disc displacement of the TMJ is rare but has probably been overlooked in the past because of a lack of well-defined imaging characteristics.