Changes In Temporomandibular Joint Research Articles

Radiographic changes in TMJ in relation to serology and disease activity in RA patients.

This study was undertaken as an attempt to assess radiographic temporomandibular joint (TMJ) changes in relation to rheumatoid factor (RF), anticitrullinated protein (ACCP) antibodies and disease activity score 28 (DAS28) in rheumatoid arthritis (RA) patients to find the best predictor of rheumatoid affection of the TMJ with the ultimate goal of maintaining TMJ function and preventing joint damage. 20 Rheumatoid Arthritis patients as well as 20 volunteers were included in this study. RA group were assessed for RF, ACCP, DAS28. Both groups were assessed by CBCT for TMJ dimensions and radiographic osteoarthritic changes. All data were statistically analyzed. Rheumatoid Arthritis group showed significantly less condylar height and more radiographic osteoarthritic changes than the control group. RF showed no significant correlation with either TMJ measurements or TMJ radiographic osteoarthritic changes. ACCP showed significant inverse correlation with condylar height and anteroposterior (AP) dimensions, but non-significant relation with mediolateral dimension and radiographic osteoarthritic changes. DAS28 showed significant inverse correlation with condylar AP and mediolateral dimensions. It also showed significant correlation with flattening of the TMJ condylar head and flattening of the articular fossa. Patients with high and moderate disease activity showed significantly smaller AP TMJ dimension than patients with low disease activity. Disease activity showed statistically significant direct correlation with all osteoarthritic changes except for erosions of the glenoid fossa and condyle. Disease Activity Score28 score and disease activity are strong indicators of TMJ affection in RA patients when compared to RF and ACCP. ACCP is a better indicator of changes in condylar measurements than TMJ osteoarthritic changes. While RF is the least efficient indicator of TMJ involvement in RA patients.

Influence of conventional and skeletal anchorage system supported fixed functional appliance on maxillo-mandibular complex and temporomandibular joint: A preliminary comparative cone beam computed tomography study

Fixed functional appliance (FFA) used in the treatment of Class II malocclusion, lead to mandibular anterior teeth proclination, thus limiting the skeletal effects of the appliance. To counter this side effect, FFA is anchored in the lower anterior region of the mandible using the skeletal anchorage system. This pilot study was done to evaluate treatment and one-year post-treatment maxillo-mandibular, and temporomandibular joint (TMJ) effects of conventional fixed functional appliance (FFA) and skeletal anchorage system supported fixed functional appliance (SAS-FFA) using cone beam computed tomography (CBCT) images. Sixteen Class II individuals were equally divided into Group I (FFA) (mean age 13.11±0.38 years) and Group II (SAS-FFA) (mean age 12.96±0.38 years). CBCT scans taken, before treatment (T0), at the end of comprehensive treatment (T1), and after one-year post-treatment (T2), were evaluated for changes in maxillo-mandibular complex and TMJ. Intraclass correlation coefficient and independent "t" test were used for repeated measures, and inter-group (mean) changes respectively. After one-year post-comprehensive treatment, SAS-FFA showed significant maxillary restriction (SNA, -1.93°, P<0.05) with significant increase in mandibular length (Go-Pog, 3.25mm, P<0.001) (Co-Gn, 7.87mm, P<0.001). SAS-FFA groups showed significant upward and backward increase in condylar volume (571 mm3, P<0.001) with anterior translation of glenoid fossa. FFA group showed significant lower dentition and vertical relationship relapse, along with non-significant changes at TMJ. SAS-FFA is an effective combination, which brings favourable changes on maxillo-mandibular complex and temporomandibular joint with non-significant relapse in comparison to FFA at one-year post-treatment.

Study of the Articular Disk of the Temporomandibular Joint in Human Ageing: Preliminary Macroscopic Analysis

The processes of human ageing involve morphological alterations of the articular structures with consequent functional impairment. There are few reports on temporomandibular joint (TMJ) changes inherent in human ageing processes. The present study aims to morphologically study the anatomical alterations of articular discs of TMJs of 4 human cadavers, males older than 50 years, previously frozen. The specimens were obtained by exposing the joint capsule followed by an incision in the joint eminence of the temporal bone and dissection of the articular ligaments, thus exposing the articular disc. The disk was delicately manipulated by means of Dietrich tweezers for the separations of the structures inserted therein. The discs presented a mean of 24.63 mm and an average spine thickness of 4.59 mm. Perforations were observed in 3 articular discs (37.5%) compatible with the reports in the literature, and 5‐part tapering (62.5%). Further investigations are needed to assess TMJ morphological alterations associated to human ageing.Support or Funding InformationFaculty of Medicine, University of São Paulo ‐ FMUSPThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Shape variation analyzer: a classifier for temporomandibular joint damaged by osteoarthritis.

We developed a deep learning neural network, the Shape Variation Analyzer (SVA), that allows disease staging of bony changes in temporomandibular joint (TMJ) osteoarthritis (OA). The sample was composed of 259 TMJ CBCT scans for the training set and 34 for the testing dataset. The 3D meshes had been previously classified in 6 groups by 2 expert clinicians. We improved the robustness of the training data using data augmentation, SMOTE, to alleviate over-fitting and to balance classes. We combined geometrical features and a shape descriptor, heat kernel signature, to describe every shape. The results were compared to nine different supervised machine learning algorithms. The deep learning neural network was the most accurate for classification of TMJ OA. In conclusion, SVA is a 3D Sheer extension that classifies pathology of the temporomandibular joint osteoarthritis cases based on 3D morphology.

Effects of wear time differences of removable functional appliances in class II patients: prospective MRI study of TMJ and masticatory muscle changes.

The aim of this prospective study was to evaluate the short-term effects of full-time and night-time wear of functional appliances on the temporomandibular joint (TMJ) and masticatory muscles and to compare the differences in craniofacial structures, TMJ, and masticatory muscles with magnetic resonance imaging (MRI). The study was carried out using cephalometric radiographs and MRI of 20 Class II patients who were treated with monoblock/twin-block appliances. The patients were divided into 2 groups: ten patients in Group 1 used their appliances all day, while ten patients in Group 2 were instructed to wear the appliances during sleep. After at least 6 months of uninterrupted treatment, post-treatment cephalograms and MRI were obtained for patients whose molar relationship improved by at least a half cusp width. Signal intensity ratios (SIR) of TMJ structures and morphological evaluations of masticatory muscles were done for all patients. It was found a significant increase in SIR values of the condylar process, articular disc, retrodiscal tissue, and masticatory muscles for all treatment groups. Length of the masseter and medial pterygoid muscles increased to varying degrees which left side of Group 2 was significantly increased (P < 0.05). The volume of all muscles also increased to varying degrees. The cephalometric and MRI findings of this study show that the treatment effects were similar for both wear schedules.

Cone beam computed tomography study of osteoarthritic alterations in the osseous components of temporomandibular joints in asymptomatic patients according to skeletal pattern, gender, and age

The aim of this study was to evaluate the prevalence of osteoarthritic alterations in the osseous components of the temporomandibular joint (TMJ) in asymptomatic patients with different skeletal patterns, gender, and age groups with cone beam computed tomography (CBCT) images. CBCT images of 213 asymptomatic patients were assessed for the presence of any degenerative changes in the condyle and fossa/eminence complex. Each TMJ was evaluated separately and was classified as normal, indeterminate for osteoarthritis, or affected by osteoarthritis. Differences were tested by using the χ2 and Fisher's exact tests (P < .05). In total, 52.3% of the joints presented some visible alteration in the osseous components. Abnormalities were detected in 32.6% of the condyles and 31.5% of the articular fossae/eminences, and flattening was the most prevalent alteration in all classes. There was no statistically significant difference in the prevalence of alterations in either the condyle or the articular fossa/eminence among the skeletal groups for the entire sample or for the gender and age subsets. There are no differences in degenerative TMJ changes in patients with or without skeletal jaw discrepancies. No differences were found when gender and age were considered.

Effect of internal derangements and degenerative bone changes on the minimum thickness of the roof of the glenoid fossa in temporomandibular joint.

The aim of this study is to investigate the effect of internal derangements and degenerative bone changes on the minimum thickness of the roof of the glenoid fossa (RGF). MRI and cone beam CT records of temporomandibular joints (TMJ) of 68 patients were evaluated retrospectively in this study. The joints were divided into three groups according to TMJ disc status which had been diagnosed in MRI: normal disc status, anterior disc displacement with reduction, and anterior disc displacement without reduction. Cone beam CT was used to evaluate the degenerative bone changes of TMJ and to measure the minimum thickness of RGF. The joints were categorized as "with osteoarthritis (OA)" or "without OA". The findings of OA were determined as erosion, osteophyte, flattening, sclerosis, and pseudocyst. No significant relationship was found between gender and the thickness of RGF (p > 0.05). RGF was found significantly higher in "with OA" group compared to "without OA" group (p < 0.001). No significant difference was found between disc displacement groups for minimum thickness of RGF (p > 0.005). No significant difference was found between condyles without erosion and condyles with erosion for the minimum thickness of RGF (p = 0.272). In the present study, osteophyte, sclerosis, flattening, and pseudocyst were found to be associated with the minimum thickness of RGF. Osteophyte, flattening, pseudocyst, and sclerosis have an influence on RGF thickness. The minimum thickness of RGF is not significantly correlated with internal derangements. Erosion is not significantly correlated with RGF thickness. RGF thickness may be unaffected by the early stages of OA.

Carcinoma of middle ear

&amp;lt;p&amp;gt;Carcinoma of the middle ear is a rare otologic disease. The development of malignancy is most commonly associated with chronic inflammation of the middle ear, although the mechanisms of this development have not been clarified yet. The symptoms of the carcinoma are not always specific and the cancer is frequently diagnosed in its advanced stage. Early evidence-based diagnosis implies a thorough evaluation and identification of cancer signs and symptoms. If ear discharge is followed by an intensive pain, bleeding from the ear, occurrence of peripheral facial nerve palsy, vertigo and hearing loss, the carcinoma is suspected, although similar clinical symptoms may be recognized in chronic otitis media as well. In addition, the characteristic signs and symptoms of carcinoma are also the following: changes in temporomandibular joint, parotid gland swelling, painless solitary mastoid swelling, neurological disorders, sudden occurrence of polyps and granulation tissue (recurrent polyps and granulation tissues after the removal), signs and symptoms of otogenic complications, as well as generalized weakness, weight loss and other biological disturbances. The diagnostic approach may include generally accepted recommendations and treatment protocols.&amp;lt;/p&amp;gt;

Temporomandibular joint osteoarthritis in human ancient skeletal remains from Late Holocene in southern Patagonia

AbstractLow prevalence of caries, high stages of dental attrition (DA), and moderate frequency of antemortem tooth loss (AMTL) were found in skeletal remains of hunter‐gatherers from southern Patagonia. However, osteoarthritis (OA) of temporomandibular joint (TMJ), possible related to oral health, has not been studied so far. The influence of hunter‐gatherer living conditions on the development of TMJ‐OA was scarcely evaluated, and analyses of degenerative changes of TMJ in nonindustrialized groups are needed. The aim of this study is to analyse the association between degenerative changes of TMJ, oral disease, and palaeodietary patterns in skeletal remains of hunter‐gatherers from southern Patagonia. Degenerative changes of TMJ were recorded in 25 adult skulls of both sexes. Eburnation of articular eminence and/or mandibular condyle was considered as pathognomonic of OA. In the absence of eburnation, OA was diagnosed when two or more of the following lesions were identified: (a) new bone formation on joint surface, (b) new bone formation of joint margins, (c) porosity on the joint surface, and (d) modification of joint contour. In the studied skeletons, it was found that OA prevalence is 28%, similar to those observed in other hunter‐gatherer populations elsewhere. TMJ‐OA is mostly related to AMTL and older age, but no relation was found with caries and DA, sex, region, dietary patterns, and chronology. However, consumption of terrestrial resources in the diet cannot be discarded as a related factor. Further studies are necessary to explore the morphological variability of the mandible and its possible relationship with different diets and dental pathologies in these populations.

Evaluation of mallear ligaments in different voxel resolutions using cone beam computed tomography.

The aim of this study was to assess the visibility of discomallear ligament and anterior mallear ligament together with anatomical morphometric measurements of petrotympanic fissure, and to determine whether the mallear ligaments correlate with the bone compartment changes of temporomandibular joint. Cone beam CT images of 275 patients were evaluated retrospectively. The visibility of discomallear and anterior mallear ligaments were evaluated by two observers. The petrotympanic fissure was classified into four groups. Morphologic features of petrotympanic fissure and mandibular fossa were also measured in sagittal, axial and three-dimensional cone beam CT reconstructed images. Pearson's χ2 test and Student's t-test were performed for statistical analysis of differences voxel sizes, age, gender, localization, temporomandibular joint and measurements (p < 0.05). Intra- and interobserver reliability was also performed. Type 3 petrotympanic fissure was more frequent in male, whereas females showed Type 1 and Type 2 petrotympanic fissure structures (p < 0.05). Anterior mallear ligament visibility on cone beam CT images was statistically higher in bone compartment changes of temporomandibular joint. In cone beam CT images, petrotympanic fissure tunnel types 1, 2, 3 and 4 were seen in 11.5, 35.63, 51.34 and 1.53% of patients, respectively. Knowledge of the anatomy may help in identifying temporomandibular joint pain and auditory symptoms due to temporomandibular disorder. Further cross-sectional studies with larger populations are needed to investigate the physiopathological relation of both disorders.

Terapia postural e manual nas disfunções temporomandibulares

Objetivos: mostrar os benefícios da terapia manual e postural nas disfunções da articulação temporomandibular (DTM) e citar as técnicas que podem ser utilizadas no tratamento dessas disfunções. Metodologia: Foi realizada uma revisão narrativa da literatura científica sobre o assunto em livros das áreas de Fisioterapia e Odontologia, artigos científicos através de periódicos e sites referentes a publicações dos últimos dez anos, utilizando como palavras chaves: terapia manual e postural, disfunções da articulação temporomandibular e articulação temporomandibular. Resultados: Foram encontrados 1.930 estudos, dentre os quais 602 foram selecionados para leitura de título/resumo e 569 excluídos devido à falta de obediência aos critérios de inclusão e, assim, um total de 33 referências foram incluídas. A literatura relata várias técnicas manuais e posturais como recursos benéficos para o tratamento da DTM, pois atua desde a fase de prevenção até a reabilitação, utilizando técnicas de terapia manual e postural com finalidade de reagrupar os músculos comprometidos e devolver a funcionalidade da articulação temporomandibular. Conclusão: A fisioterapia é de suma importância para o tratamento das DTM, pois tem como objetivo ativar a circulação sanguínea, aliviar a dor, promover o relaxamento muscular e reeducar a postura, visando promover o bem-estar do paciente.

Partial Edentulism in Patients Visiting the Dental Out-Patient Department at the Tertiary Care Centre in the Eastern Part of Nepal

Introduction: Partial edentulism is an irreversible condition resulting from various dental diseases like dental caries and periodontal lesions. Loss of teeth produces deleterious effects on masticatory function, phonetics, facial appearance and comfort of the patients. If not restored on time, it can lead to pathological changes in vertical dimension, occlusion and temporomandibular joint.&#x0D; Methods: This study was conducted in the department of Prosthodontics, CODS, BPKIHS from September 2015 to March 2016. All patients above the age of 14 years presenting with partial loss of dentition and willing to give informed consent were included in the study. Data regarding age, gender, missing teeth, cause of permanent tooth loss and age of first permanent tooth loss were collected from 750 patients.&#x0D; Results: Dental caries was the major cause of tooth loss accounting for 60.5% of the study population followed by periodontal disease (14.0%) and trauma (11.9%). First permanent tooth loss was highest in the age group of 35-44 years (22.9%). The most common type of partial edentulism was found to be Kennedy’s class III followed by class IV, class I and class II in both the arches.&#x0D; Conclusions: The most common cause of permanent tooth loss was dental caries in the study population. The first permanent tooth loss was found to be highest in age group 35-44 years. The most common type of partial edentulism was the Kennedy's class III in both the arches.

Comparison of the Bony Changes of TMJ in Patients With and Without TMD Complaints Using CBCT.

Temporomandibular joint disorders (TMD) may show a poor correlation between their clinical findings and radiological characteristics. The aim of this study was to assess the osseous alterations of temporomandibular joint (TMJ) in symptomatic and asymptomatic subjects by employing cone beam computed tomography (CBCT) images. In this study, CBCT images of 120 temporomandibular joints in 30 patients with TMJ disorder and 30 age- and sex-matched individuals without TMJ complaints were evaluated. Osteoarticular derangements of the joint were assessed by two experienced examiners. Data was statistically analyzed with SPSS software using chi-square test (p <0.05). Out of 120 CBCT images (60 in each group), at least one osseous change was observed in 90% and 86.7% joints in symptomatic and asymptomatic subjects, respectively. There were no significant differences between symptomatic and asymptomatic subjects regarding frequency of osteoarticular changes including flattening (73.3% vs. 75%), irregularity (36.7% vs. 48.3%), sclerosis (20% vs. 8.3%), cyst (3.3% vs. 3.3%), erosion (13.3% vs. 21.7%), hypoplasia (3.3% vs. 5%), ankylosis (1.7% vs. Zero), osteophyte (43.3% vs. 40%), decrease joint space (3.3% vs. 3.3%), and increase joint space (5% vs. 5%). (p> 0.05). By employing CBCT as a modern diagnostic imaging tool, findings of this study revealed that the frequency of various temporomandibular joint alterations on CBCT images is comparable in patients with and without TMD complaints, suggesting that some people with TMJ structural damage may not display clinical manifestations. Moreover, CBCT imaging might not be necessary for TMD patients and more attention should be given to clinical examination.

Positional and dimensional temporomandibular joint changes after correction of posterior crossbite in growing patients: A systematic review.

To elucidate the positional and dimensional temporomandibular joint (TMJ) changes after correction of posterior crossbite in growing patients. A systematic unrestricted search was done in six databases until June 27, 2017. A manual search in the reference lists of the included studies and gray literature was also performed. The eligibility criteria included randomized controlled trials and prospective nonrandomized controlled clinical trials and a sample of growing subjects with posterior crossbite that required maxillary expansion. Risk of bias assessment was performed using Cochrane's Risk of Bias Tool. The literature search, study inclusion, risk of bias assessment, evaluation of quality of evidence (GRADE), and data extraction were performed by two reviewers independently. Only two articles were finally eligible to be included in the qualitative analysis. Both studies were RCTs and were assessed as having unclear risk of bias. Meta-analysis was not possible since one study used cone-beam computed tomography as an assessment tool while the other used ultrasonography. One study reported significant reduction in the condylar positional difference between centric and habitual occlusion in the treatment group, while no spontaneous correction of condylar asymmetric position occurred in the control group. The other study reported minor changes of condylar position in both treatment and control groups. The current available data provide insufficient and weak evidence to form a solid and firm conclusion. There is poor, very low-quality evidence regarding the positional and dimensional effects of posterior crossbite correction on the TMJs.

Imaging of temporomandibular joint abnormalities in juvenile idiopathic arthritis with a focus on developing a magnetic resonance imaging protocol.

Inflammation and damage in the temporomandibular joint (TMJ) often develop without clinical symptoms but can lead to severe facial growth abnormalities and impaired health-related quality of life, making early diagnosis of TMJ changes crucial to identify. Inflammatory and osteochondral changes detectable through magnetic resonance imaging (MRI) occur in TMJs of approximately 40% of children with juvenile idiopathic arthritis (JIA), and no other imaging modality or physical method of examination can reliably detect these changes. Therefore contrast-enhanced MRI is the diagnostic standard for diagnosis and interval monitoring of JIA. However the specific usage of MRI for TMJ arthritis is not standardized at present. There is a recognized need for a consensus effort toward standardization of an imaging protocol with required and optional sequences to improve detection of pathological changes and shorten study time. Such a consensus imaging protocol is important for providing maximum information with minimally necessary sequences in a way that allows inter-site comparison of results of clinical trials and improved clinical management. In this paper we describe the challenges of TMJ imaging and present expert-panel consensus suggestions for a standardized TMJ MRI protocol.

Three-dimensional skeletal, dentoalveolar and temporomandibular joint changes produced by Twin Block functional appliance.

The aim of this study was to three-dimensionally analyze the net skeletal, dental, and temporomandibular joint (TMJ) treatment changes using Twin Block functional therapy in comparison to untreated subjects. The study (Twin Block) group comprised 22female patients with skeletal ClassII malocclusion due to mandibular retrusion. A total of 18skeletal ClassII untreated female subjects were included as controls. Skeletal, dental, and TMJ changes were evaluated using pre- and posttreatment/observational by cone beam computed tomography (CBCT) images. The treatment changes were compared with the growth changes observed in the control group using independent t‑tests. Compared to the changes induced by normal growth, the effective mandibular length, ramus, and corpus lengths increased by 3.19, 3.47, and 2.69 mm (P < 0.001 for all), respectively. The maxillary and mandibular incisors inclination and position were significantly reduced and increased, respectively (P < 0.001). The maxillary first molars were significantly moved distally and intruded by 1 and 0.36 mm, respectively, while the lower first molars moved mesially and intruded by 2.18 and 0.59 mm, respectively. There was asignificant change in the condylar dimensions: increase in length, width, and height by 1.28, 0.88, 1.59 on the right and by 1.60, 0.53, and 1.10 mm on the left sides, respectively. There was significant forward positioning of the right and left condyle by 1.5 and 1.3 mm, respectively. Treatment with the Twin Block functional appliance results in significant skeletal, dentoalveolar, and condylar changes in both dimensions and positions.

Calcium-/calmodulin-dependent protein kinase II in occlusion-induced degenerative cartilage of rat mandibular condyle.

Activated calcium-/calmodulin-dependent protein kinaseII (CaMKII) is important to promote chondrocytes from proliferative to pre-hypertrophic state, which probably plays a role in osteoarthritis (OA), a widespread degeneration disease with enhanced aberrant chondrocyte differentiation. Our aim was to detect the role of CaMKII, and its relationship with the feedback loop of Indian hedgehog (Ihh) and Parathyroid-related peptide (PTHrP) in the temporomandibular joints (TMJs) OA. KN93, the competitive inhibitor of CaMKII, was added to the culture medium in vitro and was locally injected to rats TMJs (n=54, female) every other day for 4weeks from the beginning of the 5th and 9th week after installing of unilateral anterior crossbite (UAC), termed as 4wk+4wk and 8wk+4wk, accordingly. The RNA expression of CaMKII α (1.49±0.09), CaMKII β (3.36±0.20), Ihh (1.88±0.06) and PTHrP (1.87±0.12) was all enhanced, especially at 24dyn/cm2 in vitro (all P<.05), accompanied with downregulated expression of cartilage matrix, but upregulated markers of chondrocytes differentiation (all P<0.05). Similarity was observed in the 4wk+4wk group in vivo. In the 8wk+4wk group, UAC upregulated the RNA expression of CaMKII α (1.81±0.24), CaMKII β (1.36±0.07) and Ihh (1.70±0.21), however, down-regulated PTHrP (0.53±0.04) (all P<.05), in consonance with the protein expression. All these changes were attenuated by KN93 (all P<.05). In conclusion, CaMKII took a role, via Ihh and PTHrP pathways, in promoting biomechanically induced TMJ chondrocytes differentiation, the initiation issue of UAC stimulated osteoarthritic changes in rodent TMJs. Inhibiting CaMKII is helpful to rescue the biomechanically stimulated cartilage degradation and prospective to be a target treatment of OA.

Magnetic resonance imaging changes in pediatric temporomandibular joint: literature review

Magnetic resonance imaging is effective to diagnose some diseases that affect the temporomandibular joint (TMJ) of children. The images allow the detection of early stages of juvenile idiopathic arthritis, cases of joint ankylosis and is currently considered the most reliable exam for an objective and noninvasive assessment of intracapsular soft tissues. The objective of this literature review was to assess some of the temporomandibular joint changes in children using magnetic resonance imaging (MRI). The assessment of TMJs of children performed through MRI make the diagnosis more accurate and objective. Detecting alterations during the early stages of juvenile idiopathic arthritis using 3T MRI devices is possible utilizing contrast tools, which as a result, provides better prognosis and treatment.

Assessment of a training programme on detection of temporomandibular joint osseous changes applying pre-defined 2D multiplane cone beam computed tomography reconstructions.

Osseous changes in temporomandibular joint disorders (TMD) are common indications for cone beam computed tomography (CBCT). The number of such cases is increasing while a number of qualified oral radiologists is limited. This study investigated the usefulness of a training programme for general dental practitioners (GDPs) regarding temporomandibular joint (TMJ) osseous changes detection in CBCT images. We selected CBCT images of 35 TMD cases and chose 5 of them to use in training 7 GDPs on detecting osseous changes in the TMJ. In evaluation directly following training, GDPs assessed the 30 remaining cases. Three qualified radiologists served as reference standard. A 2-month follow-up of training comprising evaluation of the same cases. The cases are assessed according to Ahmad etal (Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 107, 2009, 844) protocol of TMJ osseous changes in CBCT images. Sensitivity and specificity of the CBCT protocol were high, except for some criteria that did not appear in the cases. Average observer sensitivity was 65% while specificity was 87%. Average correct individual response rate was 84%. Mean agreement among the GDPs was 73%. Observer performance had improved at the 2-month follow-up. The present educational programme could be a helpful material on recognising possible osseous changes of TMJ and it can be used as a part of a training programme for GDP and for specialist candidates.

Time-course change in temporomandibular joint space after advancement and setback mandibular osteotomy with Le Fort I osteotomy

PurposeThe purpose of this study was to compare time-course changes in temporomandibular joint (TMJ) space between mandibular advancement surgery and setback surgery after sagittal split ramus osteotomy (SSRO) and Le Fort I osteotomy. Subjects and MethodsThe subjects were 46 patients (92 joints) who underwent bi-maxillary surgery. The TMJ disc position was assessed by magnetic resonance imaging (MRI) and the anterior, superior, posterior, medial and lateral joint spaces were assessed by computed tomography (CT), preoperatively and at 1 week and 1 year postoperative. The 92 joints were divided into 2 groups, namely class II (n = 46 joints), and class III (n = 46 joints) (an advanced group vs a setback group). Next, the 92 joints were divided into 2 groups comprising 36 joints with anterior disc displacement joint (ADD group) and 56 joints without (non-ADD group). Time-course changes in the measurements were compared statistically between the advanced and setback groups, and between the ADD and non-ADD groups. ResultsThere were no significant differences between the advance group and setback group regarding time-course change in all the joint spaces. However, there were significant differences between the ADD group and non-ADD group regarding time-course change in the medial, anterior, superior and posterior joint spaces (P < 0.05). ConclusionThis study suggested that ADD could affect the time-course change in TMJ space and condylar position after bi-maxillary osteotomy.