Osteoarthritic changes and condylar positioning of the temporomandibular joint in Korean children and adolescents

Age-stratified analysis of temporomandibular joint osteoarthritis using cone-beam computed tomography

Purpose

This study aimed to evaluate age-stratified radiographic features in temporomandibular joint osteoarthritis using cone-beam computed tomography.

Materials and Methods

In total, 210 joints from 183 patients (144 females, 39 males, ranging from 12 to 88 years old with a mean age of 44.75±19.97 years) diagnosed with temporomandibular joint osteoarthritis were stratified by age. Mandibular condyle position and bony changes (flattening, erosion, osteophytes, subchondral sclerosis, and subchondral pseudocysts in both the condyle and articular eminence, thickening of the glenoid fossa, joint space narrowing, and joint loose bodies) were evaluated through cone-beam computed tomography. After adjusting for sex, the association between age groups and radiographic findings was analyzed using both a multiple regression model and a multinomial logistic regression model (α=0.05).

Results

The prevalence of joint space narrowing and protruded condyle position in the glenoid fossa significantly increased with age (P<0.05). The risks of bony changes, including osteophytes and subchondral pseudocysts in the condyle; flattening, erosion, osteophyte, and subchondral sclerosis in the articular eminence; joint loose bodies; and thickening of the glenoid fossa, also significantly rose with increasing age (P<0.05). The number of radiographic findings increased with age; in particular, the increase was more pronounced in the temporal bone than in the mandibular condyle (P<0.05).

Conclusion

Increasing age was associated with a higher frequency and greater diversity of bony changes in the temporal bone, as well as a protruded condyle position in the glenoid fossa, resulting in noticeable joint space narrowing in temporomandibular joint osteoarthritis.

Assessment of condylar anatomy and degenerative changes in temporomandibular joint disorders - A scoping review

Temporomandibular disorders (TMDs) are a group of conditions that cause pain and dysfunction in the temporomandibular joint (TMJ) and muscles that control mandibular movement. In most cases, the etiology is unclear and is considered multifactorial. Recent research suggests that some forms of TMD could be associated with specific TMJ morphological characteristics. This study aims to provide a review of the reported anatomical and degenerative morphological condylar characteristics of subjects with a clinical diagnosis of TMD as described with the use of CBCT imaging, as well as the detection of potential predisposing anatomical factors. This review was developed and reported in accordance with the PRISMA-ScR Checklist. A comprehensive search was performed in five databases. Reports were screened by two independent reviewers based on preselected inclusion and exclusion criteria. 45 studies were included in this review. The most frequently reported degenerative changes associated with TMD were condylar surface erosion, flattening, osteophytes, and sclerosis. Anatomical characteristics included a small condylar size and a posterior position of the condylar head in the TMJ. The anterosuperior area of the condylar head appears to be the most frequently affected. More studies are required to determine potential specific predisposing anatomical characteristics.

Changes of Temporomandibular Joint Morphology and Symptoms in Class II Malocclusion Patients With Bilateral Sagittal Split Ramous Osteotomy

This study included 46 patients with class II malocclusion ranging in age from 19 to 39 years old treated with bilateral sagittal split ramous osteotomy (BSSRO). Left and right temporomandibular joints (TMJs) of each subject were evaluated independently with cone-beam computed tomography (CBCT) before operation (T1), 1 week after operation (T2), and 1 year after operation (T3) and assessed the effects of orthognathic surgery (OGS) on the temporomandibular joint disease (TMD) symptoms. Temporomandibular joint morphology evaluation included condylar volume, condylar area, cortical bone thickness, depth of the mandibular fossa, fossa thickness, joint nodule angle, joint space, and condyle-fossa relationship, which were calculated by using the Mimics software and 3-matic software. Data were statistically analyzed with SPSS software (P <0.05 means statistically significant). In our study, bilateral TMJs have no difference in T3. Bilateral sagittal split ramous osteotomy had no significant effect on the articular fossa. The condyle volume and surface area decreased from T1 to T3, but the cortical thickness of the bone did not change significantly. More anterior condyle positions in T1 and more posterior in T3.21 patients had at least 1 sign or symptom of TMD in T1 and 27 patients in T3. Four patients who were asymptomatic in T1 developed pain after surgery, 10 developed noises, 12 showed limited mouth opening, and 8 had abnormal opening patterns. It is concluded that more condylar posterior position after BSSRO and the reduction of condyle may be related to the enlargement of anterior space. The number of patients with joint symptoms increased postoperative, and the impact of BSSRO on TMD may be negative.

Changes in condylar position during orthodontic treatment depending on the amount of incisor retraction: a cone-beam computed tomography study

OBJECTIVES

Orthodontic treatment may be associated with temporomandibular disorders through changes in the condylar position. This study aimed to evaluate changes in the condylar position among different amounts of maxillary incisor retraction during orthodontic treatment using cone-beam computed tomography images.

MATERIALS AND METHODS

Fifty-four participants were enrolled and divided into minimal (n = 14), moderate (n = 20), and maximal (n = 20) retraction groups based on the amount of incisor retraction (< 1, 1-6, and > 6 mm, respectively). Changes in condylar position before (T0) and after (T1) orthodontic treatment were assessed for the superior, anterior, posterior, and medial joint spaces (SJS, AJS, PJS, and MJS, respectively). Changes in joint spaces were compared between T0 and T1 in each group using paired t-tests and among the three groups using analysis of variance.

RESULTS

Anterior movement of the condyle was observed in the maximal retraction group with a 0.2 mm decrease in ΔAJS and a 0.2 mm increase in ΔPJS, significantly greater than those in the minimal retraction group. The AJS and PJS showed statistically significant differences between T0 and T1 (P < 0.05) in the maximal retraction group.

CONCLUSIONS

The condyle may show a statistically significant but clinically insignificant forward movement in the maximal incisor retraction group, whereas it was relatively stable in the minimal and moderate incisor retraction groups.

CLINICAL RELEVANCE

More attention should be paid to the signs and symptoms of the condyle in patients with excessive incisor retraction during orthodontic treatment.

MRI changes and clinical characteristics in temporomandibular joints with displacement of the articular disk without reduction - a cross-sectional observational study

OBJECTIVES

This study examined changes in magnetic resonance imaging (MRI) of temporomandibular joints (TMJ) with anterior displacement disk without reduction (DDwoR) and its correlation to clinical symptoms.

METHODS

190 individuals with DDwoR were evaluated according to Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and MRI. Pain's chronicity/intensity and limited mouth opening (locking) were correlated with: TMJ degeneration (MRI T1), effusion (T2), disc's shape and position (proton density).

RESULTS

In 103 TMJ with DDwoR, hemiconvex shape (41.6%), sclerosis (45.6%) and mild effusion (47.6%) were the most prevalent findings. There was not association (p > .05) between: different DDwoR positions with pain's intensity/chronicity; effusion with locking. Disk deformation was associated with degeneration (p = .034) and pain's intensity (p = .006). Locking was associated with degeneration (p = .05).

CONCLUSIONS

Condylar osteodegeneration is often related to DDwoR. Locking by DDwoR is associated with severe levels of chronic pain and articular disk deformation.

A Comparative Study of Temporomandibular Joints in Adults with Definite Sleep Bruxism on Magnetic Resonance Imaging and Cone-Beam Computer Tomography Images

Objective: The aim was to study the imaging characteristics of the temporomandibular joint (TMJ) of definite sleep bruxers through magnetic resonance imaging (MRI) and cone-beam computer tomography (CBCT). Methods: Nineteen definite sleep bruxers diagnosed by polysomnography and twenty asymptomatic non-bruxers matched by age, gender, and education level participated in this study. After obtaining MRI and CBCT images of all TMJs of the subjects, evaluation and measurement were conducted, respectively. The analyzed parameters included disc position, disc configuration, joint effusion (JE), joint space or condyle position, and condylar bony changes. Results: Of the 38 joints in the study group, disc deformity and disc displacement of TMJs were both 57.9% when the mouth was closed, and 76.3% showed condylar bony changes, while when the mouth was open, 82% of all TMJs showed physiological biconcave discs. Comparison of joint space revealed that the anterior space was larger in the study group. There was no significant difference between the mild and the moderate to severe sleep bruxism subgroups in the changes of TMJ. Conclusion: The results demonstrated that a higher prevalence of disc deformity, disc displacement, JE, and condylar bony changes occurred in temporomandibular joints of sleep bruxers. These changes were not related to the severity of sleep bruxism.

Analysis of the relationship between condylar changes and anterior disc displacement with reduction: a preliminary study

OBJECTIVES

To predict temporomandibular joint (TMJ) anterior disc displacement with reduction (ADDWR) from condylar shape, position, and dimensions obtained from CBCT images.

METHODS

This cross-sectional study was performed on 17 patients suffering from temporomandibular disorders diagnosed by history taking according to the chart of the American Association of orthodontists, clinical examination according to the Helkimo index and MRI. CBCT and MRI examinations were performed within one-week interval. Disc position, diagnosed by MRI was used as the gold standard. TMJs with posterior disc displacement or anterior disc displacement without reduction were excluded. Qualitative and quantitative analyses were performed on CBCT images to find the correlation between condylar variables and ADDWR. A logistic regression model was created to estimate ADDWR from condylar dimensions (height, width and depth).

RESULTS

Condylar shape and condylar position in the glenoid fossa were significantly correlated with ADDWR (P < 0.05). Condylar width, height and depth were significantly smaller in condyles with ADDWR compared to condylar dimensions in normal disc position. Logistic regression analysis could be used to predict the probability of anterior disc displacement with reduction from condylar dimensions.

CONCLUSION

Condylar shape, position, and dimensions assessed by CBCT are significantly correlated with ADDWR of the TMJ. Substituting the values of condylar width, height and depth in the equation suggests the probability of ADDWR.

Evaluation of the lateral pterygoid muscle area, attachment type, signal intensity and presence of arthrosis, effusion in the TMJ according to the position of the articular disc

PURPOSE

The aim of this study was to evaluate the lateral pterygoid muscle (LPM) area, attachment type, signal intensity and presence of arthrosis, effusion in the temporomandibular joint (TMJ) by magnetic resonance imaging (MRI) according to the position of the articular disc.

METHODS

The study included a total of 126 TMJs belonging to 69 patients over the age of 18 years who had MRI due to TMJ complaints. The position of the articular disc, the area, attachment type, and signal intensity of the LPM, the presence of arthrosis on the condyle surface, and the presence of effusion in the joint space were evaluated.

RESULTS

The attachment type of the LPM did not show a statistically significant difference according to the position of the articular disc. The groups were not statistically different in terms of LPM intensity. Although the distribution of the LPM area was found to be low in the anterior disc displacement with reduction (R+DD) group and high in the anterior disc displacement without reduction (R-DD) group. It was determined that the rate of arthrosis at the condyle head was significantly higher in the R-DD group compared to the normal disc position group. The incidence of effusion was found significantly higher in the R-DD and R+DD groups than joints with normal disc position.

CONCLUSIONS

Pathological changes in LPM and TMJ can be detected by MRI. In the group with R-DD, the rate of arthrosis at the condyle head, effusion, LPM area, and intensity of the Sup. LPM were higher.

A comparative study of condyle position in temporomandibular disorders patients with chewing side preference using cone-beam computed tomography

BACKGROUND

Chewing side preference (CSP) could cause structural and morphological changes of temporomandibular joint (TMJ) and has been suggested as one etiology of temporomandibular disorders (TMDs), but the condylar position in TMD patients with CSP is unknown.

OBJECTIVE

To compare the condylar position in the TMD patients with and without CSP.

METHODS

Ninety TMD patients with unilateral symptom (69 with CSP and 21 without CSP) and 20 asymptomatic participants received cone-beam computed tomography. The condylar position was determined based on the measurements of sagittal joint spaces. Intergroup and intragroup comparisons of the condylar position were performed.

RESULTS

The condyles in asymptomatic participants located nearly randomly in anterior, centric, and posterior positions. Patients without CSP had significantly more posterior condyles than asymptomatic participants (57.1% vs 30.0%, P<0.05). In patients with CSP, 50.7% of the condyles on the preferred chewing side and 42.0% on the unpreferred side located posteriorly, reaching no significant level compared with the asymptomatic participants and patients without CSP (P>0.05). The symptomatic joints and asymptomatic joints in patients with CSP and without CSP showed no significant differences in condylar position. While patients without CSP had significantly more posterior condyles in symptomatic joints than asymptomatic participants (P<0.05), patients with CSP showed a trend towards more posterior condyles in symptomatic joints compared with the asymptomatic participants (53.6% vs 30.0%, P=0.054).

CONCLUSION

Condylar position is not a strong indicator to differentiate CSP-related TMDs from none-CSP-related TMDs. Posterior condyle could not be viewed as one indicator of TMD.

In children and adolescents with temporomandibular disorder assembled with juvenile idiopathic arthritis - no association were found between pain and TMJ deformities using CBCT

Background

Children and adolescents with juvenile idiopathic arthritis (JIA) may suffer from temporomandibular disorder (TMD). Due to this, imaging diagnosis is crucial in JIA with non-symptomatic TM joint (TMJ) involvement. The aim of the study was to examine the association between clinical TMD signs/symptoms and cone-beam computed tomography (CBCT) findings of TMJ structural deformities in children and adolescents with JIA.

Methods

This cross-sectional study is part of a longitudinal prospective multi-centre study performed from 2015–2020, including 228 children and adolescents aged 4–16 years diagnosed with JIA, according to the International League of Associations for Rheumatology (ILAR). For this sub-study, we included the Bergen cohort of 72 patients (32 female, median age 13.1 years, median duration of JIA 4.5 years). Clinical TMD signs/symptoms were registered as pain on palpation, pain on jaw movement, and combined pain of those two. The severity of TMJ deformity was classified as sound (no deformity), mild, or moderate/severe according to the radiographic findings of CBCT.

Results

Of 72 patients, 21 (29.2%) had pain on palpation at and around the lateral pole, while 41 (56.9%) had TMJ pain upon jaw movement and 26 (36.1%) had pain from both. Of 141 TMJs, 18.4% had mild and 14.2% had moderate/severe structural deformities visible on CBCT. CBCT findings were not significantly associated with either the pain on palpation or the pain on jaw movement. A significant difference was found between structural deformities in CBCT and the combined pain outcome (pain at both palpation and movement) for both TMJs for the persistent oligoarticular subtype (p = 0.031).

Conclusions

There was no association between painful TMD and CBCT imaging features of the TMJ in patients with JIA, but the oligoarticular subtype of JIA, there was a significant difference associated with TMJ pain and structural CBCT deformities.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01870-z.

Measurement of the trabecular bone structure of the TMJ region in patients with transverse maxillary deficiency: a CBCT fractal analysis study

OBJECTIVE

This study aimed to evaluate the effect of transverse maxillary deficiency on condylar morphology via visual examination and fractal analysis of cone beam computed tomography (CBCT) scans.

STUDY DESIGN

In total, 97 patients with posterior crossbite or maxillary narrowness and 36 control patients were included. The presence of degenerative changes in the bilateral condyles was evaluated with CBCT. Fractal dimension (FD) was calculated on the condylar images using ImageJ.

RESULTS

Degenerative bone changes were discovered in 38 of the 133 scans (28.6%). There was no significant difference between the groups in terms of the incidence of degenerative changes for either the right or left sides (P ≥ .670). In coronal sections and in mean measurements, FD was significantly lower in the control group compared with the other groups in the right condyle (P ≤ .031). No significant differences were found between the mean FD values of the condyles with degenerative bone changes or the mean FD values of the normal condyles (P ≥ .256).

CONCLUSIONS

In the presence of maxillary transverse deficiencies, degenerative bone changes in the mandibular condyle were not significantly different, but the FD of the right condyle was found to be higher compared with the control group.

Evaluation of the dimensions, morphology, and position of the mandibular condyles in individuals with neurofibromatosis 1: a case-control study

OBJECTIVES

The aim of this study was to evaluate the mandibular condyles of neurofibromatosis 1 (NF1) individuals without facial plexiform neurofibroma using cone beam computed tomography images.

MATERIALS AND METHODS

Eighty cone beam computed tomography scans (160 mandibular condyles) were analyzed: 40 from NF1 individuals (study group) and 40 from individuals without NF1 (control group). The anteroposterior and mediolateral dimensions, height, and volume of the mandibular condyles were measured. The mandibular condyles were classified according to their morphology: healthy (absence of morphological changes), with flattening (loss of rounded contour of at least one of the surfaces), with erosion (loss of continuity of the cortical bone), with osteophyte (exophytic formation of the condyle surface), and with sclerosis (any increase in the cortical thickness in the load-bearing areas). Furthermore, the position of the mandibular condyles in relation to the joint fossa in an anteroposterior view was classified as anterior, concentric, or posterior.

RESULTS

The study group had a higher anteroposterior dimension of the mandibular condyles compared with the control group (p < 0.05). There were no differences in condylar morphology and position between both groups (p > 0.05). The morphological alterations were not associated with sex or age in any group evaluated (p > 0.05). For both groups, the concentric position was the most common. For the study group, there was a significant difference in the condylar position between the sides (p < 0.05).

CONCLUSIONS

NF1 individuals without facial plexiform neurofibroma present a high prevalence of condyles with a large anteroposterior dimension and asymmetric position in the joint fossa. However, no morphological and volumetric changes were observed in the mandibular condyles of them.

CLINICAL RELEVANCE

The knowledge of the TMJ alterations in individuals with NF1 is important to establish an evaluation protocol, which would allow early intervention if indicated.

Evaluation of the relationship between tympanic plate morphology and degenerative bone changes of condyle and articular eminence

INTRODUCTION

This study aimed to evaluate the relationship between tympanic plate morphology and degeneration of temporomandibular joint (TMJ) condyle and articular eminence (AE).

MATERIAL AND METHODS

Cone beam computed tomography images of 700 patients (345 males, 355 females) were evaluated. The prevalence and location of tympanic plate pneumatization (TPP) and foramen tympanicum (FT) were recorded. Sagittal scans of the TMJs were classified according to the degenerative bone changes of condyle and AE (flattening, osteophytes, erosion, sclerosis, and subcortical cysts).

RESULTS

TPP was found in 106 of 700 patients (15.2%) while FT was found in 165 (23.2%) of the patients. TPP and FT were bilateral in 52 (49.1%) patients and 46 (27.9%) patients, respectively. The mean axial diameter of FT was 2.53mm and the mean sagittal diameter was 2.52mm. The most common degenerative changes for condyle and AE were flattening.

CONCLUSION

To know these structures is important for surgical operations in the region of TMJ and ear to prevent complications. CBCT is useful to evaluate these anatomical landmarks and the relationship between them and the degenerative bone changes of condyle and AE.

Evaluation of the relationship between the degenerative changes and bone quality of mandibular condyle and articular eminence in temporomandibular disorders by cone beam computed tomography

Objective: To evaluate whether there was a relationship between the degenerative bone changes and bone quality of the mandibular condyle and articular eminence in patients with temporomandibular disorder (TMD).Methods: The study group consisted of 100 patients with TMD. "Diagnostic Criteria/TMD" was used to identify the pathologies. Degenerative bone changes and bone qualities were detected by cone beam computed tomography; the bone qualities were classified using the Bone Quality Index (BQI) scale.Results: No statistically significant difference was found between degenerative bone changes and bone quality of the temporomandibular joint (TMJ) according to gender (p > 0.05). However, degenerative bone changes were more frequent than articular eminence in the mandibular condyle. BQI Type III was the most common bone quality among all types of degenerative bone changes.Discussion: Although no causality relationship was found between the bone quality and degenerative bone changes, low bone quality was found in TMD patients.

Improvement of bone-erosive temporomandibular joint (TMJ) abnormalities in adolescents undergoing non-surgical treatment: a longitudinal study

OBJECTIVES

To investigate the longitudinal changes of the imaging temporomandibular joint (TMJ) characteristics in young patients with TMJ-related symptoms and treated with non-surgical methods. The severity of self-reported symptoms at follow-up was also investigated.

METHODS

A cone beam CT (CBCT)/CT follow-up examination [median follow-up 4.1 (1.3-6.4) years] was performed in 22 patients with erosive TMJ abnormalities [baseline median age 16 (12-18) years]. Imaging characteristics were analyzed and the changes between the examinations were categorized as (A) improvement, (B) no change, or (C) worsening. Severity of follow-up symptoms was evaluated using Jaw Functional Limitation Scale (JFLS-8) and Graded Chronic Pain Scale (Grade 0-IV). Analyses were performed separately for left and right TMJ. Findings at baseline and follow-up were compared using McNemar test to account for dependencies. Changes in proportions of hard tissue findings between examinations were assessed using Wilcoxon signed ranks test.

RESULTS

A significant reduction in the proportion of patients with erosive abnormalities was found [59.1%, 95% CI (36.4-79.3) %]. Baseline erosions improved in 9/12 (75%) right and 14/15 (93%) left TMJs. About half repaired; developed an intact cortical outline. Number of joints with osteophytes increased (right: p < 0.04, left: p < 0.003). New osteophytes were mostly found in joints with erosive findings. Low or no limitation of jaw function (Jaw Functional Limitation Scale) was found in 12/22 (55%) and no or low intensity of pain (Graded Chronic Pain Scale Grade 0 or I) in 19/22 (86%) at follow-up.

CONCLUSION

We found a high potential for repair of erosive TMJ abnormalities. However, the patient series was small. The majority of patients assessed their symptom severity at follow-up as low.

Spatial analysis of mandibular condyles in patients with temporomandibular disorders and normal controls using cone beam computed tomography

OBJECTIVES

The aim of the study is to investigate the condylar position and its relation to articular eminence and axial condylar angle in temporomandibular joint disorder (TMD) patients and in normal controls using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

CBCT temporomandibular joint (TMJ) images of 70 participants (38 males and 32 females, mean age 26.4 years) were analyzed. They were divided into control group (including 35 subjects) and study group (including 35 subjects). Linear measurements of joint space and condyle determined the condylar position of each TMJ. Articular eminence height and inclination were also measured with axial condylar angle to determine its relation to condylar position. Independent and paired sample t-test was applied to compare between the groups and TMJ sides of the same group at significance level of 0.05.

RESULTS

Statistical significant differences were found between males and females of both groups regarding superior joint space (SJS), lateral joint space, A-P, and M-L condyle distance (P < 0.05). SJS, medial joint space (MJS), and eminence angle were greater (P < 0.01) in male's joints with TMD with flatter axial condylar angle (P < 0.05), when compared with normal TMJ counterpart. Females TMJs showed significantly higher values of MJS of affected side when compared with normal counterpart with flatter axial condylar angle (P < 0.05).

CONCLUSION

Superior and MJS parameters were the ones that showed significant differences between affected and nonaffected joints. The mean axial condylar angle was smaller in joints with abnormal TMJ. This indicates that the condyles of the affected joints may rotate inward.

Changes in Condylar Position After Mandibular Reconstruction With Condylar Head Preservation by Computed Tomography

PURPOSE

Condylar position can change after mandibular reconstruction using the free fibula flap. The present study evaluated changes in condylar position using computed tomography (CT) after mandibular reconstruction with condylar head preservation.

MATERIALS AND METHODS

This retrospective study consisted of 16 patients. CT data of 32 temporomandibular joints (TMJs) were recorded before surgery (T0), 7 to 10 days after surgery (T1), and 16.8 ± 7.4 months after surgery (T2). The anteroposterior condylar position was evaluated using the method of Pullinger and Hollender (Oral Surg Oral Med Oral Pathol 62:719, 1986). Repeated-measures analysis of variance (P = .05) was performed.

RESULTS

Data of 16 patients were obtained for statistical analysis. Condylar position changed over time after mandibular reconstruction. The ipsilateral condyles moved anteroinferiorly after surgery (T0 to T1) and tended to move anterosuperiorly during follow-up (T1 to T2). No major changes were noted in the contralateral condyles.

CONCLUSION

Condylar positions showed obvious changes over time after mandibular reconstruction with condylar preservation. Nevertheless, additional studies are warranted to further evaluate the relation between condylar position and TMJ function.

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

OBJECTIVE

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.

STUDY DESIGN

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).

RESULTS

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.

CONCLUSIONS

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.

Assessment of condylar morphology and position using MSCT in an Asian population

OBJECTIVES

The purpose of the present study was to investigate the volume, surface, morphometric index (MI), and position of the condyle in a normal population by applying Mimics 17.0 software. Then, the difference between left and right sides, sex, and age can be explored, which will contribute to establish the reference value of condylar morphology and position in normal individuals, and help us to study characteristics of condylar morphology and position in abnormal individuals.

MATERIALS AND METHODS

Three-hundred subjects were enrolled in our study from the radiology department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital. They were divided into three groups according to the age: group 1 (18-24 years old), group 2 (25-34 years old), and group 3 (35-44 years old). Each group included 100 subjects (with 50 males and 50 females). They were examined using multislice computed tomography (MSCT) after that. All images of condyle were reconstructed by Mimics 17.0 software, so as to measure the volume, surface, and MI of condyle, and to analyze the position of condyle in the articular fossa by means of joint spaces.

RESULTS

The differences of condylar volume, surface, and MI between left and right sides were not obvious (P > 0.05). The condylar volume and surface were greater in males than females (P < 0.05), while their condylar MI existed no difference (P > 0.05). No statistical differences were found in volume and surface among three age groups. However, the MI of group 1 was statistically lower than that of group 3 (P < 0.05). On the other hand, no significant differences were found between left and right condylar position (P > 0.05). Nevertheless, there were significant differences of condylar position regarding the gender and age (P < 0.05).

CONCLUSIONS

This study showed no significant differences in condylar morphology and position between left and right sides, but factors of gender and age were proven to have a certain influence on the morphology and position of the condyle. This information can be clinically useful in establishing the diagnostic criteria for condylar morphology and position in the normal Asian population.

CLINICAL RELEVANCE

Examination of condylar morphology and position is important for evaluating the abnormalities and bony changes that affect the temporomandibular joint (TMJ). So, this will be conducive to the diagnosis and the evaluation of therapeutic effect of temporomandibular joint diseases. Also, it is important to evaluate these indexes prior to commencing orthodontic treatment, because TMJ abnormalities play a critical role in orthodontic treatment planning.

Association between condylar position and vertical skeletal craniofacial morphology: A cone beam computed tomography study

OBJECTIVE

Condylar position may play an important role in the establishment of different craniofacial morphologies. The aim of the present study was to determine the possible association between condylar position and vertical skeletal craniofacial morphology in subjects with normal sagittal skeletal pattern using CBCT.

METHOD AND MATERIAL

The CBCT images of 45 patients with Class I sagittal skeletal pattern were classified into three balanced groups on the basis of SN-MP angle. Each group contained 15 subjects: low angle, normal angle and high angle. The condylar position was determined for the left and right joints. Chi square test was applied to assess the association between condylar position and vertical skeletal growth pattern.

RESULTS

The condyles were more anteriorly-positioned in patients with high angle vertical pattern than in those with normal and low angle vertical pattern. No significant differences were found in condylar position between low angle and normal angle subjects.

CONCLUSION

A significant correlation between condylar position and vertical skeletal pattern was found in the present study. This relationship can be considered for predicting and establishing a proper treatment plan for temporomandibular diseases during orthodontic treatment.

Effect of Field of View on Detection of Condyle Bone Defects Using Cone Beam Computed Tomography

In maxillofacial imaging, cone beam computed tomography (CBCT) is currently the modality of choice for assessment of bony structures of the temporomandibular joint (TMJ). Factors affecting the quality of CBCT images can change its diagnostic accuracy. This study aimed to assess the effect of field of view (FOV) and defect size on the accuracy of CBCT scans for detection of bone defects of the TMJs. This study was conducted on 12 sound TMJs of 6 human dry skulls. Erosions and osteophytes were artificially induced in 0.5, 1, and 1.5-mm sizes on the anterior-superior part of the condyle; CBCT scans were obtained with 6, 9, and 12-inch FOVs by NewTom 3G CBCT system. Two maxillofacial radiologists evaluated the presence/absence and type of defects on CBCT scans. The Cohen kappa was calculated to assess intra- and interobserver reliability. The Mann-Whitney U test was applied to compare the diagnostic accuracy of different FOVs.In comparison of 6- and 12-inch, 9- and 12-inch FOVs in detection of different sizes of erosive lesions, difference was significant (P <0.05), whereas difference between 6- and 9 inch just in 0.5-mm erosive lesion was significant (P = 0.04). In comparison of 6- and 12-inch FOVs in detection of different sizes of osteophyte lesion, difference was significant (P < 0.05), whereas between 6- and 9-inch FOVs statistically significant difference was not observed (P > 0.05). The highest and the lowest diagnostic accuracy of CBCT scans for condyle defects were obtained with 6-inch and 12-inch FOVs, respectively. Diagnostic accuracy of CBCT scans increased with an increase in size of bone defects.

Assessment of the trabecular structure of mandibular condyles in patients with temporomandibular disorders using fractal analysis

OBJECTIVES

The aim of this study was to evaluate changes in the trabecular structure of the mandibular condyle in patients with temporomandibular disorders (TMDs) using fractal analysis.

STUDY DESIGN

A total of 100 patients ages 18 to 73 years were clinically assessed using the Diagnostic Criteria for Temporomandibular Disorders. The control group was age- and sex-matched with the patient group. Panoramic radiographs were obtained using a Kodak 8000 digital device with 73 kVp and 5 mA fixed parameters. The degree of degeneration in the mandibular condyles was calculated. Regions of interest (84 × 84 pixels) were selected within the cortical boundary of the mandibular condyle, and the fractal dimension (FD) was calculated using ImageJ version 1.48.

RESULTS

Radiographic degenerative changes were more frequently present and more severe in the patient group (P < .001). The mean value of FD was 1.22 ± 0.06 in the patient group and 1.25 ± 0.06 in the control group (P = .001). A significant decrease in FD was observed (P = .001) in the left temporomandibular joints of the patient group, whereas a nonsignificant decrease in FD was observed in the right temporomandibular joints (P = .073) as degenerative changes increased.

CONCLUSIONS

Lower FD values were associated with more severe degenerative changes in the patient group. The trabecular structure of condyles in patients with TMD exhibited decreased complexity when erosive and sclerotic changes were evident. As a result, fractal analysis enhanced the use of panoramic radiography in detecting degenerative changes in patients with TMD.

The usefulness of diagnostic imaging for the assessment of pain symptoms in temporomandibular disorders

The causes of pain symptoms in the temporomandibular joint (TMJ) and masticatory muscle (MM) regions may not be determined by clinical examination alone. In this review, we document that pain symptoms of the TMJ and MM regions in patients with temporomandibular disorders (TMDs) are associated with computed tomography and magnetic resonance (MR) findings of internal derangement, joint effusion, osteoarthritis, and bone marrow edema. However, it is emphasized that these imaging findings must not be regarded as the unique and dominant factors in defining TMJ pain. High signal intensity and prominent enhancement of the posterior disk attachment on fat saturation T2-weighted imaging and dynamic MR imaging with contrast material are closely correlated with the severity of TMJ pain. Magnetic transfer contrast, MR spectroscopy, diffusion tensor imaging, and ultrasonography findings have helped identify intramuscular edema and contracture as one of the causes of MM pain and fatigue. Recently, changes in brain as detected by functional MR neuroimaging have been associated with changes in the TMJ and MM regions. The thalamus, the primary somatosensory cortex, the insula, and the anterior and mid-cinglate cortices are most frequently associated with TMD pain.

Correlation between condylar position and different sagittal skeletal facial types

OBJECTIVE

Condylar position may play a key role in the stability of orthodontic treatment of patients presenting with different skeletal patterns. The aim of the present study was to assess via cone beam computed tomography (CBCT) correlations between condylar position and sagittal skeletal relationship.

PATIENTS AND METHODS

Condylar positions in CBCT images of 20 patients presenting with a Class I skeletal pattern, 20 with a Class II skeletal pattern, and 20 with a Class III skeletal pattern were evaluated retrospectively. The χ (2) test was used to assess the correlation between condylar position and sagittal skeletal relationships.

RESULTS

The condyles were anteriorly positioned in patients with Class II skeletal pattern in comparison with those with Class I and III skeletal patterns. No significant differences in condylar position between Class I and Class III subjects were detected.

CONCLUSION

A significant correlation between condylar position and sagittal skeletal patterns was observed in the present study. This relationship should be considered when planning and carrying out the appropriate orthodontic treatment for temporomandibular anomalies.

Cone-Beam Computed Tomographic Assessment of Mandibular Condylar Position in Patients with Temporomandibular Joint Dysfunction and in Healthy Subjects

Statement of the Problem. The clinical significance of condyle-fossa relationships in the temporomandibular joint is a matter of controversy. Different studies have evaluated whether the position of the condyle is a predictor of the presence of temporomandibular disorder. Purpose. The purpose of the present study was to investigate the condylar position according to gender in patients with temporomandibular disorder (TMD) and healthy controls using cone-beam computed tomography. Materials and Methods. CBCT of sixty temporomandibular joints in thirty patients with TMD and sixty joints of thirty subjects without TMJ disorder was evaluated in this study. The condylar position was assessed on the CBCT images. The data were analyzed using Pearson chi-square test. Results. No statistically significant differences were found regarding the condylar position between symptomatic and asymptomatic groups. Posterior condylar position was more frequently observed in women and anterior condylar position was more prevalent in men in the symptomatic group. However, no significant differences in condylar position were found in asymptomatic subjects according to gender. Conclusion. This study showed no apparent association between condylar positioning and clinical findings in TMD patients.

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.

Association between mandibular condylar position and clinical dysfunction index

OBJECTIVES

Condylar position in the glenoid fossa has been associated with temporomandibular disorders. The purpose of the present study was to investigate the correlation between clinical dysfunction index (Di) and mandibular condylar position in patients with temporomandibular joint dysfunction (TMD) using cone beam computed tomography (CBCT).

METHODS

In this cross-sectional study, participants were recruited from the Department of Maxillofacial Radiology at Shiraz Dental University in Iran. The condylar position was assessed on the CBCT images of 120 temporomandibular joints in 60 patients with TMD. Patients were divided into 3 groups based on Helkimo's clinical Di. The chi-square test was used to correlate degree of the Helkimo's Di with the mandibular condylar position. The p value was set at 0.05.

RESULTS

A total of 60 patients (42 women and 18 men; mean age, 33.4 years) participated in this study. Significant differences in condylar position were found among the 3 groups (Di I, II, and III) (p < 0.05). Patients with mild to moderate TMD were found to have anteriorly and concentric seated condyles. Posteriorly seated condyles were found in patients with severe TMD.

CONCLUSION

Condylar position is associated with different severity of TMD.

Regional 3D superimposition to assess temporomandibular joint condylar morphology

OBJECTIVES

To investigate the reliability of regional three-dimensional registration and superimposition methods for assessment of temporomandibular joint condylar morphology across subjects and longitudinally.

METHODS

The sample consisted of cone beam CT scans of 36 patients. The across-subject comparisons included 12 controls, mean age 41.3 ± 12.0 years, and 12 patients with temporomandibular joint osteoarthritis, mean age 41.3 ± 14.7 years. The individual longitudinal assessments included 12 patients with temporomandibular joint osteoarthritis, mean age 37.8 ± 16.7 years, followed up at pre-operative jaw surgery, immediately after and one-year post-operative. Surface models of all condyles were constructed from the cone beam CT scans. Two previously calibrated observers independently performed all registration methods. A landmark-based approach was used for the registration of across-subject condylar models, and temporomandibular joint osteoarthritis vs control group differences were computed with shape analysis. A voxel-based approach was used for registration of longitudinal scans calculated x, y, z degrees of freedom for translation and rotation. Two-way random intraclass correlation coefficients tested the interobserver reliability.

RESULTS

Statistically significant differences between the control group and the osteoarthritis group were consistently located on the lateral and medial poles for both observers. The interobserver differences were ≤0.2 mm. For individual longitudinal comparisons, the mean interobserver differences were ≤0.6 mm in translation errors and 1.2° in rotation errors, with excellent reliability (intraclass correlation coefficient >0.75).

CONCLUSIONS

Condylar registration for across-subjects and longitudinal assessments is reliable and can be used to quantify subtle bony differences in the three-dimensional condylar morphology.

Nontraumatic bifid mandibular condyles in asymptomatic and symptomatic temporomandibular joint subjects

Purpose

This study was performed to determine the prevalence of bifid mandibular condyles (BMCs) in asymptomatic and symptomatic temporomandibular joint (TMJ) subjects with no traumatic history, and to assess their impact on clinical and radiographic manifestations of TMJ.

Materials and Methods

A total of 3,046 asymptomatic and 4,378 symptomatic patients were included in the study. Cone-beam computed tomography (CBCT) images were reviewed for bifid condyles. T-tests were used to compare the frequency of BMCs when stratified by symptom, gender, and side. In BMC patients, the clinical features of pain and noise, osseous changes, and parasagittal positioning of the condyles were compared between the normally shaped condyle side and the BMC side using chi-squared tests.

Results

Fifteen (0.49%) asymptomatic and 22 (0.50%) symptomatic patients were found to have BMCs. Among the bilateral cases, the number of condyles were 19 (0.31%) and 25 (0.29%), respectively. No statistically significant differences were found between asymptomatic and symptomatic patients, between female and male patients, or between the right and left sides (p>0.05). Compared with the normally shaped condyle side, the BMC side showed no statistically significant differences in the distribution of pain and noise, parasagittal condylar position, or condylar osseous changes, with the exception of osteophytes. In the symptomatic group, osteophytes were found more frequently on the normally shaped condyle side than the BMC side (p<0.05).

Conclusion

BMCs tended to be identified as an incidental finding. The presence of BMC would not lead to any TMJ symptoms or cause osseous changes.