Comparison of diagnostic accuracy of film and digital tomograms for assessment of morphological changes in the TMJ

Diagnosis of TMJ degenerative diseases by panoramic radiography: is it possible? A systematic review and meta-analysis

OBJECTIVE

The objective of this work was to determine the diagnostic accuracy of panoramic radiography in detecting degenerative diseases of the temporomandibular joint.

METHOD

The protocol was registered at the PROSPERO website. To consider the eligibility of studies to be included/excluded from this review, the acronym "PIRDS" was used and appropriate word combinations and truncations were adapted in the following electronic databases: PubMed/Medline, EMBASE, Latin American and Caribbean Literature on Health Sciences, Web of Science, Scopus, and Cochrane Library.

RESULTS

A total of 2572 references, after the removal of duplicates, were retrieved from the eight electronic databases. After reading the titles and abstracts, a total of 26 articles were selected for full reading, of which ten were excluded, resulting in 16 articles included for qualitative synthesis. All in vivo studies were classified as having a low risk of bias. Regarding in vitro studies none of the included studies scored below 80% in the overall evaluation.

CONCLUSIONS

Both in vitro and in vivo studies consistently report a low accuracy in detecting degenerative diseases of the temporomandibular joint using panoramic radiography.

CLINICAL RELEVANCE

Cone-beam computed tomography offers a superior image quality without overlapping structures and a higher accuracy compared to panoramic radiography. However, panoramic radiography can still serve as an initial examination when combined with a clinical assessment. CBCT should be reserved for cases where there are evident clinical and/or radiographic alterations that recommend its use. This approach ensures a judicious and cost-effective use of CBCT resources.

Assessment of Interexaminer Agreement in the Detection of Condyle Morphology and positioning with Two Methods: Radiographic and Tomographic

AIM

This study aims at evaluating the interexaminer agreement between radiographic and tomographic methods to determine condyle morphological variations and positioning.

MATERIALS AND METHODS

The sample comprised 100 individuals aged 13 to 30 years, from the patient files of University of North Paraná. The assessment of condyles morphology and positioning was performed in images of digital panoramic radiography (DPR) and reconstructed panoramic images from the cone beam computed tomography (CBCT) scans, by using the Dolphin three-dimensional (3D) program. The condyle morphology was categorized as flat, convex, and angular as well as its positioning classified into anterior, posterior, and concentric. Three calibrated examiners performed this subjective evaluation. After that, another examiner performed an objective assessment of the condyles positioning using tomographic sagittal scans of the condyles, applying the same 3D program. This objective evaluation of the condyle position, considered the gold standard (GS), was achieved by using a formula based on the measurement values of the joint spaces, anterior and posterior. The kappa test was used to assess the interexaminer agreement in determining the condyles morphology and positioning, as well as between the condyle positioning results determined by the examiners and the GS.

RESULTS

The results showed poor agreement among examiners and between the subjective and objective condyle positioning evaluation.

CONCLUSION

It was concluded that the panoramic radiography (PR), either digitalized or reconstructed from CBCT scans, is not suitable for determining variations in condyle morphology and position.

CLINICAL SIGNIFICANCE

Whenever it is necessary to evaluate the mandibular condyle during the orthodontic screening, the orthodontist should consider another image modality better than the PR.

Accuracy of scanography using storage phosphor plate systems and film for assessment of mandibular third molars

OBJECTIVES

The aim of this study was to compare the diagnostic accuracy of two digital photostimulable storage phosphor (PSP) systems and film for assessment of mandibular third molars before surgery.

METHODS

110 patients were referred to have both their mandibular third molars removed. Each patient underwent a radiographic examination with scanography using either Digora (Soredex, Helsinki, Finland) and film or VistaScan (Dürr Dental, Beitigheim-Bissingen, Germany) and film in a randomized paired design. Two observers examined the following variables on the scanograms: bone coverage, angulation of the tooth in the bone, number of roots, root morphology and the relationship to the mandibular canal. In 75 of the pairs (Digora/film pair = 38 and Vista/film pair = 37) both third molars were eventually removed. During and after surgery the same variables were assessed, which served as reference standard for the radiographic assessments. The Wilcoxon signed-rank test tested differences in accuracy (radiographic compared with surgical findings) between Digora/film and between Vista/film.

RESULTS

There was no statistically significant difference between the diagnostic accuracy of film and either of the two digital receptors for assessment of mandibular third molars before surgery (P > 0.05), although Digora obtained a higher accuracy than film.

CONCLUSIONS

Scanography is a valuable method for examination of mandibular third molars before removal and the PSP digital receptors in this study were equal to film for this purpose.

Evaluation of the severity of temporomandibular joint osteoarthritic changes related to age using cone beam computed tomography

OBJECTIVES

The aim of this study is to evaluate and correlate with age the severity of temporomandibular joint (TMJ) osteoarthritic changes using cone beam CT (CBCT).

METHODS

The images of 71 patients with findings of degenerative arthritis were retrieved from the computer data base. All patients had been examined with CBCT (NewTom 9000 QR-DVT). Left and right TMJs were evaluated independently for each patient. TMJ evaluation included: (a) bony changes of the condyle (flattening, erosion, sclerosis, osteophytes, resorption); (b) joint space (normal, increased, reduced, bony contact between the condyle and the mandibular fossa); and (c) bony changes of mandibular fossa (normal, sclerosis, erosion, resorption). The radiographic findings were statistically analysed.

RESULTS

Significant differences in the mean age were found: (a) between absent and moderate erosion (P = 0.019), as well as between absent and extensive erosion (P = 0.048); (b) between absent and extensive formation of osteophyte (P = 0.003), as well as between slight and extensive formation of osteophyte (P = 0.025); (c) between normal joint space and bony contact (P = 0.0002), as well as between reduced joint space and bony contact (P = 0.001).

CONCLUSIONS

Degenerative arthritis is an age-related disease. The progression and severity of osseous changes in the condylar head and mandibular fossa are increased with age. In older age groups, patients are expected to have more frequent and severe progressive degenerative bony changes due to the development of TMJ osteoarthritis than patients in younger age groups.

Temporomandibular joint adaptations following two-phase therapy: an MRI study

AIM

To document the alterations within the condyle-glenoid fossa (C-GF) complex and the positional changes of the glenoid fossa in the cranium after removable functional appliance therapy and after the completion of fixed appliance therapy.

SETTING AND SAMPLE

The Department of Orthodontics, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India. The study sample consisted of 12 growing children (eight girls and four boys) between 10 and 14 years of age with skeletal Class II division 1 malocclusion selected on well defined criteria.

MATERIALS AND METHODS

All patients were treated with either the Twin Block or the Bionator appliance followed by fixed appliances. Mean total treatment duration was 28 months. The changes in and around the C-GF complex were evaluated using MRI at pre-treatment stage, after functional appliance therapy and at the completion of fixed mechanotherapy.

RESULTS

Forward condylar position within the glenoid fossa and articular disc retrusion with respect to the condylar head were statistically significant after functional appliance therapy. However, the condyles had a relatively concentric position within the glenoid fossa, while the articular disc resumed its pre-treatment position at the end of the treatment. Linear measurements from the centre of the external auditory meatus to the post-glenoid spine revealed a 1.3-mm forward relocation of the post-glenoid spine along the Frankfurt Horizontal plane.

CONCLUSIONS

Forward relocation of the C-GF complex seems to be one of the mechanisms of action of functional appliances, while the internal anatomic arrangement within the temporomandibular joint (TMJ) complex normalizes to its pre-treatment position.

Cone beam CT and conventional tomography for the detection of morphological temporomandibular joint changes

OBJECTIVE

To compare the diagnostic accuracy of cone beam CT images with conventional tomographic images for the detection of morphological temporomandibular joint (TMJ) changes.

METHODS

80 dry human skulls were scanned using a NewTom 3G scanner and lateral and frontal reconstructions of the right and the left TMJs were performed. In addition, lateral and frontal cross-sectional tomograms of the skulls' TMJs were obtained in a Cranex Tome unit with Digora storage phosphor plates. Naked-eye inspection of the TMJs performed by three observers served as the gold standard for the true presence of morphological changes. The mandibular fossae were excluded from the study due to few changes in this joint component. The NewTom and the conventional tomographic images were examined by three independent observers using a binary scale for the presence of morphological changes in the condyle (flattening, defects and osteophytes) and the articular tubercle (flattening and defects). The accuracy for the different types of changes in relation to the condyles and the articular tubercles was expressed as sensitivity and specificity values, whereas the diagnostic accuracy for a general assessment including all changes in both joint components was expressed by the sum of cases where the gold standard and the radiographic scores were not identical (absolute difference). Differences between the two radiographic modalities were tested by paired t-test.

RESULTS

Detection of the various types of morphological changes in relation to the condyle and the articular tubercle assessed separately resulted in no significant differences between the two radiographic modalities, with the exception of bone defects in the articular tubercle examined on frontal views alone where the specificity with tomography was significantly higher than with cone beam CT. Detection of all morphological changes in relation to both the condyle and the articular tubercle showed a significantly higher accuracy with tomography than with cone beam CT using lateral views alone, but there was no significant difference between the two modalities using frontal views alone and lateral and frontal views in combination.

CONCLUSION

In general, no significant differences in diagnostic accuracy for the detection of bone changes in the condyle and in the articular tubercle were found between cone beam CT images and conventional tomograms.