Prevalence and Characteristics of Articular Eminence Pneumatization: A Cone-Beam Computed Tomographic Study

The relation between persistent foramen tympanicum and degenerative bone alterations in temporomandibular joint region

OBJECTIVES

The aim of this study was to evaluate, using cone-beam computed tomography (CBCT), the relationship of persistent foramen tympanicum (PFT) with degenerative changes in the temporomandibular joint (TMJ) and the presence of pneumatized glenoid fossae and articular eminences.

METHOD

Two experienced oral and maxillofacial radiologists evaluated 510 CBCT scans, from which 94 patients were divided into two groups: G1-patients with PFT and G2-control group. The location of the PFT, presence, or absence of degenerative TMJ changes and morphology were evaluated. Similarly, all images were evaluated for the presence of pneumatized articular eminence and glenoid fossa. The Chi-square test and Fisher's Exact test were used for the categorical variables. A multinomial logistic regression model was performed for subgroup analysis. To assess the estimation-chance occurrence of TMJ alterations the Odds Ratio analysis was used.

RESULTS

Statistically significant results were found for erosion, planning, and subchondral cyst. Regarding TMJ morphology, significant results were found for: round, flat, and others. Moreover, it was possible to observe that patients who had the PFT were approximately 48 times more likely to manifest TMJ alterations and approximately 3 times more likely to manifest articular eminence pneumatization.

CONCLUSION

Since individuals who have FTP have a greater chance of having TMJ and PEA changes, it is important for the dental radiologist to be aware of these signs in CBCT scans for a correct diagnosis.

TRIAL REGISTRATION NUMBER

CAAE: 34328214.3.0000.0104 (11/30/2014).

Normal Variants of the Oral and Maxillofacial Region: Mimics and Pitfalls

A normal variant is defined as an incidental, often asymptomatic, imaging finding that mimics a true pathologic condition. Given the complex anatomy and wide variety of normal variants in the oral and maxillofacial region, a thorough understanding of commonly encountered normal variants in this region is essential to avoid misinterpretation and unnecessary further imaging or interventions. Moreover, familiarity with normal variants that are known to become symptomatic at times is necessary to facilitate further workup and guide the treatment plan. Intraoral radiography and panoramic radiography, which are unique to oral and maxillofacial radiology, provide two-dimensional (2D) images. Hence, the overlapping of structures or the displacement of the tomographic layer on images can confuse radiologists. It is crucial to understand the principle of 2D imaging to avoid being confused by ghost images or optical illusions. In addition, understanding the normal development of the maxillofacial region is essential when interpreting maxillofacial images in children or young adults because the anatomy may be quite different from that of mature adults. Knowledge of changes in the jaw bone marrow and each tissue's growth rate is essential. It is also necessary to know when the tooth germ begins to calcify and the tooth erupts for diagnostic imaging of the maxillofacial region. The authors describe imaging findings and clinical manifestations of common normal variants in the oral and maxillofacial region, divided into four parts: the maxilla, mandible, tooth, and temporomandibular joint, and discuss the imaging approach used to differentiate normal variants from true pathologic conditions. Online supplemental material is available for this article. ^©RSNA, 2022.

Articular eminence pneumatization in patients with different sagittal skeletal patterns: Cone-beam computed tomography study

Objectives:

This study objectives to evaluate the type and degree of articular eminence pneumatization in individuals with different sagittal skeletal patterns.

Material and Methods:

Cone-beam computed tomography images of 139 patients were included in the study. The population was divided into groups according to their sagittal skeletal anomalies by A point-nasion-B point angle measurement. The laterality, grade, and type of pneumatization were recorded. Pearson Chi-square test and Fisher’s exact test were performed to evaluate gender, sagittal skeletal anomalies, pneumatization type, and grade.

Results:

A pneumatized articular eminence (PAT) was found in 74.8% of the population. Grade 1 pneumatization and the multilocular type where the most common pneumatization. There were no correlations between sagittal skeletal anomalies and pneumatization grades.

Conclusion:

The prevalence of PAT was high concerning the previous studies. However, there were no correlations between the sagittal skeletal anomalies, pneumatization type, and grade. Clinicians must always be aware of the potential for pneumatizations as they may cause untoward complications.

Comparison of mastoid air cell volume in patients with or without a pneumatized articular tubercle

Purpose

The aim of this study was to compare mastoid air cell volumes in patients with or without a pneumatized articular tubercle (PAT) on cone-beam computed tomography (CBCT) images.

Materials and Methods

The CBCT images of 224 patients were retrospectively analyzed for the presence of PAT. The Digital Imaging and Communications in Medicine data of 30 patients with PAT and 30 individuals without PAT were transferred to 3D Doctor Software. Mastoid air cell volumes were measured using semi-automatic segmentation on axial sections. Data were analyzed using SPSS version 20.0.

Results

The patients with PAT and those without PAT had a mean mastoid volume of 6.31±2.86 cm³ and 3.25±1.99 cm³, respectively. There were statistically significant differences in mastoid air cell volumes between patients with and without PAT regardless of sex and mastoid air cell side (P<0.05).

Conclusion

The detection of PAT on routine dental radiographic examinations might be a potential prognostic factor that could be used to detect extensive pneumatization in the temporal bone. Clinicians should be aware that there may be widespread pneumatization of mastoid air cells in patients in whom PAT is detected. Advanced imaging should be performed in these cases, and possible complications due to surgical interventions should be considered.

Temporal Bone Pneumatization: Relationship With Sex and Variants of the Ethmoid and Sphenoid Bone

ABSTRACT

Pneumatization variants of the temporal bone have a crucial importance in several surgical interventions. However, very few data are known about possible correlation with other pneumatization variants.Pneumatization of glenoid fossa, petrous apex, and infralabyrinthine portion of temporal bone was assessed in 200 computed tomography scans, equally divided between males and females (18-92 years). Pneumatization variants of the ethmoid (concha bullosa, agger nasi, pneumatized crista galli) and the sphenoid sinuses (pneumatized pterygoid processes, anterior clinoid processes, dorsum sellae, volume) were recorded as well.Differences in prevalence of each pneumatization type according to sex and side, among different portions of the temporal bone, and between temporal bone and the pneumatized variants of the ethmoid bone and sphenoid sinuses, were assessed through chi-square test (P < 0.05). Differences in sphenoid volume among different pneumatization degrees of the temporal bone were assessed through 1-way analysis of covariance test (P < 0.05).Pneumatization of the petrous apex and the infralabyrinthine portion was significantly more frequent in males than in females, whereas pneumatization of the glenoid fossa was more often observed on the right side (P < 0.05). Variants of the temporal bone are all related one with each other in males, whereas in females only the relationship between pneumatized petrous apex and infralabyrinthine portion was found. Moreover, in females the pneumatized petrous apex was related with pneumatized anterior clinoid process, and the pneumatized infralabyrinthine portion was related with the sphenoid sinus volume.Results may be useful for predicting these important variants in planning surgical interventions of the cranial base.

Evaluation of pneumatic cavities surrounding temporomandibular joint by cone beam computed tomography

OBJECTIVE

The purpose of this study was to detect the prevalence and characteristics of pneumatization in the roof of the glenoid fossa (PRGF) and articular eminence (PAT) by using cone beam computed tomography (CBCT) images.

MATERIAL AND METHOD

CBCT images of 378 patients (756 TMJ) were analyzed to determine the PRGF and PAT. Twenty-eight patients were excluded due to some reasons such as trauma, degeneration, previous surgical operation of temporomandibular joint (TMJ). Pneumatization was detected in 297 of 350 patients, but not pneumatization in 53 patients. Age, gender, laterality (unilateral, bilateral) and lacunarity (unilacunar, multilacunar) were recorded. Unilateral types were also noted as right and left localization. Chi-square test was used to evaluate relationship between pneumatization and gender, lacunarity and laterality.

RESULTS

PRGF and/or PAT were diagnosed in 491 (70%) TMJ components whom 178 (51%) were male and 172 (49%) were female with mean age of 40.38±18.34 years. In total, 103 (35%) of the patients had unilateral and 194 (65%) patients had bilateral pneumatization.

CONCLUSION

CBCT provides reliable and precise images to detect pneumatization surrounding TMJ structure in comparison to 2D images. Evaluation of TMJ components accurately before surgical intervention is crucial to prevent complication or increase the success of therapy.

Temporal bone pneumatization in patients with dentofacial deformities: cone beam computed tomography study

Pneumatization in the osseous components of the temporomandibular joint (TMJ) may represent a complicating factor in TMJ surgery. This study determined the prevalence and characteristics of pneumatized articular eminence (PAE) and pneumatized glenoid fossa (PGF) using cone beam computed tomography (CBCT) scans of patients with and without dentofacial deformities. The CBCT of 587 asymptomatic patients (216 class I, 179 class II, 192 class III) were assessed to determine PAE and PGF. Age, sex, laterality, and type (uni/multilocular) of pneumatization were recorded. Differences were tested using the χ² test and binary logistic regression models (P<0.05). Overall, 63.7% of patients presented some pneumatization: 15.5% presented both PAE and PGF, 0.9% presented only PAE, and 47.4% presented only PGF. The multilocular type was more frequent in both PAE and PGF (P<0.001). There was a significant difference regarding dentofacial deformity for PAE (P=0.021), with a higher frequency in class I. There were no differences according to sex, age, or laterality. The absence or lower frequency of pneumatization in class II and III patients may indicate continuous remodelling of the joint, which is submitted to abnormal occlusion forces. This knowledge is helpful for TMJ surgery planning, particularly as patients with dentofacial abnormalities may more often be candidates for TMJ surgery.

Prevalence of pneumatization of the articular eminence and glenoid fossa viewed on cone-beam computed tomography examinations in a Turkish sample

OBJECTIVE

The aim of this study is to evaluate the prevalence of the pneumatization of the articular eminence and glenoid fossa (PAT and PGF, respectively) using cone-beam computed tomography (CBCT).

METHODS

CBCT images of 1000 patients (511 females and 489 males) representing 2000 regions of interest (the glenoid fossa and articular eminence of each patient) were examined retrospectively with regard to age, gender, laterality, and type of pneumatization. The mean age of the female patients was 39.66 and that of males was 39.79. Suitable images from patients aged 16 years and over found in the archives of CBCT images were included in the study. The data were assessed using IBM SPSS 20 and statistical comparisons between two categorical variables were conducted using Chi square tests.

RESULTS

It was observed that 14.7% of the patients had PAT and 47.1% had PGF. There was no significant difference in PAT and PGF prevalence between ages, age ranges, and gender in our study (p > 0.5).

CONCLUSIONS

It is important to evaluate the pneumatic cells in the articular eminence and glenoid fossa regions before surgery. It was also found that CBCT is more helpful in detecting pneumatization than plain film.