Assessments of inclinations of the mandibular fossa by computed tomography in an Asian population

Evaluation of prevalence of temporomandibular disorders based on DC / TMD Axis I diagnosis in Turkish population and correlation with Axis II

PURPOSE

The prevalence of DC / TMD diagnosis of individuals with internal derangement of TMJ who want to receive TMD treatment in a tertiary clinic in the Turkish population and comparison of the criteria applied in Axis I and Axis II.

METHODS

This study was carried out on 200 individuals older than 18 years of age who have internal disorder of Temporomandibular Joint (TMJ). Diagnostic Criteria for Temporomandibular Disorders (DC / TMD) Axis I and II were applied.

RESULTS

The female to male ratio of individuals with internal derangement of TMJ in the Turkish population was 3.5. The Pearson correlation coefficient between the internal derangement of the Right TMJ and the internal derangement of the Left TMJ is 0.804 and has a statistically significant relationship (p <0.05).

CONCLUSIONS

For DC / TMD, a more comprehensive study is needed to compare the results found in the Turkish population with other populations.

Articular Eminence Morphology of American Historic and Contemporary Populations

Objectives

This study was performed to determine the values of the articular eminence inclination (AEI), the articular eminence height (AEH), and the length of the articular eminence curved line (AEL) among American prehistoric and contemporary populations.

Materials and methods

The study was carried out on 120 human dry skulls divided into 4 groups: Illinois group (IP), Kentucky group (KP), African Americans group (AAP) and American Caucasians group (ACP). Each group comprised 30 human dry skulls. Measurements of AEI (by two methods), AEH and AEL were performed using computer software on 5 sagittal sections through silicone molds of the articular eminence. The obtained results were statistically analyzed at significance level of p < 0.05.

Results

No statistically significant differences of AEI, AEH and AEL values were obtained among American populations (IP, KP, AAP, ACP) neither by body side, sex and age (p > 0.05). The mean AEI M1 values ranged from 31.56° to 38.72°, the mean AEI M2 values ranged from 44.14° to 58.37°, the mean AEH ranged from 5.82 to 6.86 mm, and the mean AEL values ranged from 11.57 to 12.73 mm.

Conclusions

AEI, AEH, AEL values are variables, but they did not differ significantly among American populations. Left-right differences as the result of natural body asymmetry were not statistically significant. Sex and age did not significantly affect the articular eminence morphology.

Cone-beam computed tomographic assessment of the inclination of the articular eminence in patients with temporomandibular disorders and chewing side preference

Background

Chewing side preference (CSP) has been proposed as one etiology of temporomandibular disorders (TMDs) as it can induce the structural changes of the temporomandibular joint. But its association with the inclination of the articular eminence (IAE) is unknown. This study aimed to compare IAE between patients with CSP and without CSP.

Methods

Cone-beam computed tomography images of 90 patients with TMD (mean age of 45.6 years, 69 with CSP, 21 without CSP) and 20 participants without TMD and CSP (mean age of 41.3 years) were measured to compare IAE and depth of the glenoid fossa (DGF)

Results

IAE and DGF showed a positive correlation among all the participants. Compared with the participants without TMD and CSP, the TMD patients without CSP presented a similar IAE but with a significantly higher value of DGF (p < 0.05); in contrast, the TMD patients with CSP presented a significantly greater IAE and DGF (p < 0.05). No bilateral differences in IAE and DGF were observed in all the participants. Except the male patients with CSP had a deeper fossa than did the female, no differences in IAE and DGF according to gender were observed.

Conclusions

TMD patients with CSP seem to have a deep glenoid fossa with steep eminence which might be considered one characteristic imaging feature.

Radiographical investigation of the condylar position using three-dimensional imaging (a comparative Iraqi study)

Objective: To investigate the condylar position in an Iraqi sample of patients with temporomandibular joint disorders (TMDs) using cone beam computed tomography.Methods: The study included 20 patients with temporomandibular disorders and 20 healthy patients with normal temporomandibular joints (40 individuals in total). Reference landmarks from the sagittal aspect were used to measure various straight distances between the glenoid fossa and condyle, such as the anterior, posterior, and superior joint spaces. The inclination of the articular eminence was also evaluated.Results: There was a statistically significant difference in inclination in the TMD group when patients were categorized by sex. Males had larger superior space and inclination compared with females.Conclusion: Cone beam computed tomography can offer essential information about variations in the TMD group and can be used as one of the indicators for such variations for good diagnosis and treatment.

Comparison of Glenoid Fossa Morphology Between Different Sagittal Skeletal Pattern Using Cone Beam Computed Tomography

Morphology of glenoid fossa might help the clinician in the diagnosis, establishing more biological treatment modalities and treatment response between patients with different skeletal malocclusions. This study aimed to assess the glenoid fossa morphology in different sagittal facial types using CBCT. The CBCT images of 64 patients with normal vertical growth patterns were classified into class I, class II, and class III based on the skeletal sagittal analysis. Depth, width, and angle of glenoid fossa were measured and assessed on CBCT images. One-way analysis of variance (ANOVA) and Tukey post-hoc test were used to compare mean values among the groups. There was a significant statistical difference in means of glenoid fossa' width between groups with skeletal class III and skeletal class I (P value: 0.038). However, no significant statistical differences were found in angle(P value = 0.18) and depth (P value = 0.40) of glenoid fossa among 3 groups. This study showed the glenoid fossa in class I patients was wider than class III patients. There were no statistically significant differences in the angle and depth of glenoid fossa in patients with a different sagittal skeletal pattern.

Temporomandibular Joint Osseous Morphology of Class I and Class II Malocclusions in the Normal Skeletal Pattern: A Cone-Beam Computed Tomography Study

(1) Background—The aim of the present study was to evaluate the correlation between the temporomandibular joint (TMJ) osseous morphology of normal skeletal pattern individuals with different dental malocclusions by using cone-beam computed tomography (CBCT). (2) Methods—The CBCT images of bilateral TMJs in 67 subjects with skeletal class I and average mandibular angle (26 males and 41 females, age range 20–49 years) were evaluated in this study. The subjects were divided into class I, class II division 1, and class II division 2 according to the molar relationship and retroclination of the maxillary incisors. Angular and linear measurements of TMJ were evaluated and the differences between the groups were statistically analyzed. (3) Results—Intragroup comparisons showed statistical differences for articular eminence inclination, the width of the glenoid fossa, the ratio of the width of the glenoid fossa to the depth of the glenoid fossa, the condylar angle, and the intercondylar angle between the malocclusion groups. The measurements of the glenoid fossa shape showed no significant difference between the left and right sides. Females showed more differences in the morphological parameters of TMJ between the three malocclusion groups than the males. (4) Conclusion—The present study revealed differences in the TMJ osseous morphology between dental class I and class II malocclusions in the normal skeletal pattern.

Morphometric analysis of the mandibular fossa in dentate and edentulous patients: A cone beam computed tomography study

STATEMENT OF PROBLEM

Mandibular fossa roof thickness and lateral inclination could be associated with the presence of bone changes in the mandibular condyle in dentate and edentulous patients. However, literature regarding the relationship between the presence and absence of teeth and the morphologic features of the temporomandibular joint is lacking. This knowledge could provide a better understanding of changes affecting the correct functioning of the stomatognathic system.

PURPOSE

The purpose of this clinical study was to assess the mandibular fossa roof thickness and lateral inclination in relation to sex, presence or absence of teeth, and bone changes in the mandibular condyle through cone beam computed tomography (CBCT).

MATERIAL AND METHODS

CBCT scans of 100 individuals (50 dentate and 50 edentulous) were evaluated in terms of mandibular fossa roof thickness and lateral inclination. Bone changes in the mandibular condyle were classified dichotomously in relation to osteophytes, erosion, sclerosis, and flattening. Differences were assessed with the Student t test, the chi-square test, and 2-way analysis of variance (ANOVA), with Tukey post hoc tests (α=.05).

RESULTS

Sex was not related to mandibular fossa measurements. Edentulous participants showed a higher mandibular fossa lateral inclination (P<.001) and lower roof thickness (P=.001) than dentate participants. When the association between bone changes in the mandibular condyle was evaluated in dentate and edentulous groups, only sclerosis showed a statistically significant association (P<.001). The 2-way ANOVA showed that the mandibular fossa roof thickness was lower in edentulous participants in the presence of flattening and erosion and that the mandibular fossa lateral inclination was higher in the presence of osteophytes, erosion, and sclerosis (P<.001). Among dentate participants, the mandibular fossa lateral inclination was higher in the presence of flattening (P=.024).

CONCLUSIONS

Mandibular fossa roof thickness and lateral inclination are not associated with sex. However, tooth absence and bone changes in the mandibular condyle are related to mandibular fossa measurements.

Is There an Association between Temporomandibular Disorders and Articular Eminence Inclination? A Systematic Review

(1) Background: In order to determine the correlation between the inclination of articular eminence (AEI) and the development of temporomandibular disorders (TMDs), a systematic review was performed. (2) Methods: A systematic literature research was conducted between 1946 and January 2020, based on the following electronic databases: PubMed, Cochrane Library, Embase, Medline, Scope, SciELO, and Lilacs. Observational studies, analytical case-control studies, and cohort studies written in English were identified. The articles were selected and analyzed by two authors independently. The PICO format was used to analyze the studies and the Newcastle-Ottawa Scale (NOS) was used to verify the quality of the evidence. (3) Results: Sixteen articles were included in this review, ten case-control studies and six cohort studies. Eight articles (50%) established a positive relation between AEI and TMDs and eight (50%) did not. The scientific quality was medium-low, mainly influenced by the exposure to the risk of bias and the lack of clinical methods with adequate consistency and sensitivity on the diagnosis of TMDs. (4) Conclusions: It is controversial to establish a causal relationship between the TMDs and the AEI in the field of stomatology, due to limited and inconclusive evidence. However, it is suggested that the AEI defined by some specific methods may be associated with some special pathological stages of TMDs. High-quality prospective studies are required to draw any definitive conclusions.

Comparative cone-beam computed tomography evaluation of temporomandibular joint position and morphology in female patients with skeletal class II malocclusion

Objective

This study was performed to evaluate the position and morphology of the temporomandibular joint in female patients with skeletal class II malocclusion and to investigate the association between temporomandibular joint disorders and facial types using cone-beam computed tomography.

Methods

A lateral cephalogram was taken to determine the skeletal class of each participant. Sixty female patients aged 16 to 28 years were divided into high-angle, low-angle, and control groups. The shape of the condyle–fossa was measured and assessed on cone-beam computed tomography images of the 120 temporomandibular joints.

Results

Some condylar shape measurements displayed statistically significant differences among the groups. No significant differences were found in the length of the condyle, width of the glenoid fossa, or height of the articular eminence among the three groups. The posterior condylar position was more frequently observed in the low-angle group, whereas the anterior condylar position was more prevalent in the high-angle group.

Conclusion

The present study revealed differences in the condyle–fossa morphology and position in female patients with skeletal class II malocclusion with different vertical facial types.

A radiological evaluation of the effects of edentulousness on the temporomandibular joint

BACKGROUND

The articular eminence of the temporomandibular joint is an anatomical structure exposed to functional loads resulting from masticatory forces. Tooth loss may change the biomechanics of the masticator system, and the articular eminence can be affected by this change.

OBJECTIVE

The aim of this study is to examine the relationship between the edentulousness and the articular eminence inclination of the temporomandibular joint.

METHODS

The articular eminence inclination was measured in panoramic radiographs in the right and left temporomandibular joint on a total of 100 patients (50 dentate and 50 edentulous). The articular eminence inclination of dentate and edentulous patients was compared, as well as the influence of gender and duration of edentulousness.

RESULTS

The mean articular eminence inclination value in the dentate group (42.6 ± 4.3⁰ ) was higher than that of the edentulous group (35.1 ± 4.7⁰ , P < .001). Although there was no significant difference between males and females in the dentate group with regard to articular eminence inclination (42.0 ± 4.7⁰ and 42.9 ± 4.1⁰ , respectively, P = .373), in the edentulous group, males had higher values as compared to females (37.1 ± 4.7⁰ and 34.2 ± 4.5⁰ , respectively, P = .003). Finally, the duration of edentulousness and the degrees of articular eminence inclination values did not show positive correlations (P = .782).

CONCLUSION

According to the results of this study, we found that edentulous patients had lower articular eminence inclination than dentate patients, and it was more prominent in female than male patients.

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.

Prevalence of temporomandibular disorders discovered incidentally during routine dental examination using the Research Diagnostic Criteria for Temporomandibular Disorders

OBJECTIVES

The aim of this study was to assess the prevalence of temporomandibular disorders (TMDs) discovered incidentally during routine dental examination, identify disease patterns, and evaluate patients' attitude toward accepting treatment.

STUDY DESIGN

A total of 3009 patients were examined at the University Dental Hospital Sharjah (Sharjah, United Arab Emirates). Research Diagnostic Criteria for TMD (RDC/TMD) Axes I and II were used for assessment. Patients with acute/serious dysfunction symptoms underwent cone beam computed tomography examination. Magnetic resonance imaging was used to confirm the diagnosis of disk displacement.

RESULTS

Non-self-reported TMD prevalence was 10.8% (n = 325). Among patients with TMDs, women were diagnosed more often (65.85%) (P < .05) and those between ages 25 and 45 years (65.54%) (P < .05). Axis I assessment revealed disk displacement with reduction (group IIa) was the most common (40.92%). Axis II chronic pain grade showed that 32.62% of patients with TMDs experienced chronic pain, whereas 66.77% had mild disability. Interest in pursuing treatment was indicated by 92.31% of patients. Cone beam computed tomography and magnetic resonance imaging assessments changed the primary diagnosis in 26.08% and 18.47% of cases, respectively.

CONCLUSIONS

TMD screening during routine dental examination led to the diagnosis of non-self-reported TMDs, most commonly related to disk displacement with reduction. Radiographic assessment was important to confirm TMD diagnosis. Patients diagnosed with TMD during dental screening expressed interest in pursuing treatment.

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.

Is there enough evidence so that mandible can be used as a tool for sex dimorphism? A systematic review

Statement of Problem:

One of the most challenging tasks for forensic science is to identify the unknown human skeletal remains of deceased individuals. Study of sex by distinguishing the various morphological characteristics of bones is utmost important in forensic anthropology and for medico-legal assessment.

Purpose:

The purpose of this article is to review the literature, to find if there is sufficient evidence to establish the use of mandible in sex identification.

Materials and Methods:

An electronic search was performed to identify suitable literature, using database of MEDLINE, PubMed, and EBSCOhost. Published articles in between January 2000 and April 2015 were searched. The main focus of search was on the various parameters of mandible studied in last 15 years for sex dimorphism. The focus was on the articles published on radiographic studies as well as on morphometric studies of dry mandible in which skeletal parameters were studied. The screening of titles and abstracts were done, suitable literature that fulfilled the inclusion criteria was selected for a full-text reading.

Results:

The initial literature search resulted in 89 articles, out of which only 36 articles fulfilled the inclusion criteria and were included in this systematic review.

Conclusion:

Out of 16 radiographic studies, 14 showed statistically significant results that the adult mandible could be used with increased sensitivity and objectivity to identify both sex and population affinity compared to other standard analytical techniques, whereas two studies showed insignificant results. Out of 20 morphometric studies of dry mandible 15 studies showed a positive correlation between sex dimorphism and mandibular parameters and five studies did not show any positive correlations between the two.

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.

Correlation between bony changes measured with cone beam computed tomography and clinical dysfunction index in patients with temporomandibular joint osteoarthritis

OBJECTIVES

To investigate the correlation between clinical dysfunction index (Di) and condylar bony changes, glenoid fossa bony changes and joint space changes.

METHODS

Clinical data and cone beam computed tomography (CBCT) images of 240 patients with temporomandibular joint osteoarthritis (TMJ OA) were analyzed. The patients were assigned a score of Helkimo's clinical Di ranging from 1 to 25 and thereafter divided into 3 groups by the degree of Helkimo's Di. The condylar bony changes observed with CBCT were graded by the classification method of Koyama et al. Glenoid fossa bony changes and joint space changes were both classified as "positive" or "negative". Spearman's rank correlation test was used to correlate the score or degree of Helkimo's Di with the maximum condylar bony changes, glenoid fossa bony changes, and joint space changes.

RESULTS

There was a significant correlation between the Helkimo's Di score and the maximum condylar bony changes (P ≤ 0.0001) and glenoid fossa bony changes (P ≤ 0.0001), and there was a poor correlation between the Helkimo's Di score and joint space changes (P = 0.184). Furthermore, there was a significant correlation between the degree of Helkimo's Di and the maximum condylar bony changes (P ≤ 0.0001) and glenoid fossa bony changes (P ≤ 0.0001), but there was a poor correlation between the degree of Helkimo's Di and joint space changes (P = 0.346).

CONCLUSIONS

Both the score and degree of Helkimo's Di were highly correlated with maximum condylar changes and glenoid fossa bony changes, but not with joint space changes.

Biometry of the temporomandibular joint using computerized tomography

PURPOSE

In the present study, we performed biometric characterization of the temporomandibular joints (TMJs) of clinically normal subjects.

METHODS

Fifty-one healthy volunteers underwent high-resolution computerized tomography examination of the TMJs in the position of maximal intercuspidation according to a standardized protocol. Frontal and sagittal reconstructions were then performed to obtain measurements and indexes in three planes of space.

RESULTS

Correlations are observed with age, gender, amplitude of mouth opening and presence of dental abrasion. The lateral stability index reflects the degree of mobility of the temporo-discal compartment of the joint. The coverage index reflects how much the mandibular condyle is inserted into the articular fossa and may be related to the risk of occurrence and severity of regressive remodeling phenomena.

CONCLUSIONS

This study supports the interest in examining morphological aspects of the TMJ and performing intra-articular measurements. The biometric examination of the TMJ has important applications in the domain of TMJ pathology.

Correlation between articular eminence steepness measured with cone-beam computed tomography and clinical dysfunction index in patients with temporomandibular joint dysfunction

OBJECTIVE

The purpose of this study was to investigate the correlation between articular eminence steepness and clinical dysfunction index (Di) in patients with temporomandibular joint dysfunction (TMD) using cone-beam computed tomography (CBCT).

STUDY DESIGN

In this study, CBCT images of 60 temporomandibular joints in 30 patients with TMD were evaluated. The eminence inclination values were measured on CBCT images. Patients were subdivided into 3 groups based on Helkimo's clinical Di. The data were analyzed using Spearman's rho correlation coefficient test.

RESULTS

The results of the present study did not confirm any significant differences in the values of articular eminence inclinations among the 3 groups (P value >.05).

CONCLUSION

Based on the present study, there is no apparent relationship between the articular eminence inclination and the clinical Di in patients with TMD.