Interpretation of mandibular condyle fractures using 2D- and 3D-computed tomography

How good is good enough? Lessons learned from review of outcomes of 50 patients following extraoral open reduction and internal fixation of condylar neck and base fractures at a regional major trauma centre

The management of mandibular fractures is routine owing to their frequency, particularly those of the mandibular condyle, which are invariably common. Notwithstanding disparities in the literature, the international consensus towards which fractures of the mandibular condyle benefit from open surgical intervention is almost universally accepted. Closed reduction or non-operative management may be utilised in certain circumstances. Whilst outcome research has addressed complications with respect to operative side effects, outcomes related to the quality of bone repair and the setting in which this is delivered have not been universally addressed. The aim of this study was to determine the predictability of translating an indicated operative treatment plan into an acceptable functional result. We evaluated the outcomes of 59 extracapsular condylar fractures in 50 patients who were treated by extraoral open reduction and internal fixation (ORIF) between March 2021 and August 2022. We reviewed demographic data, surgical approach, and plating strategy, and critically evaluated the clinical and radiological outcomes. Whilst we found that the quality of reduction was not universally perfect, the majority were within tolerance, which we set according to the Strasbourg Osteosynthesis Research Group (SORG) definition for minimal displacement (<2 mm overlap and 10° angulation). The cohort had good functional occlusion and minimal long-term postoperative complications. Two patients required re-operation for non-union, and we discuss causality in these cases. In conclusion, we found that ORIF of condylar neck and base fractures is predictable in real-time surgical practice with respect to functional outcome. However, if imperfectly reduced, there is a small risk of non-union.

Direct Three-Dimensional Diagnosis of Ex Vivo Facial Fractures

The aim of the present study is to assess the reliability and accuracy of different 3-dimensional (3D) reconstruction algorithms in detecting undisplaced condylar, zygomatic arc, and orbital rim fractures based on cone-beam computed tomography data set. Twenty sheep heads were used in the present study. Sixty fractured and 60 nonfractured (control) zones were randomly allocated. Three groups consisting of nondisplaced fractures of condyle (CF, n = 20), orbital (OF, n = 20), and zygomatic arc (ZF, n = 20) were created by using a diamond cutting disc. Soft tissues were only dissected and no fractures were generated in the control group (n = 60). The 3D reconstructions were created by using multiplanar reconstruction (MPR), surface rendering (SR), volume rendering (VR), and maximum intensity projection (MIP) algorithms. Final 3D models were examined in Osirix software (Pixmeo SARL, Bernex, Switzerland) by 6 observers. Diagnostic accuracies of each algorithm were statistically compared by receiver operating characteristics (ROC) and area under the ROC curves (AUCs). For the detection of CF, AUC for VR algorithm was found to be statistically larger than that of MIP while AUCs for VR and MIP were larger than those of MPR and SR for OF detection. For the detection of ZF, AUCs for MPR and VR were significantly larger than those of MIP and SR (P < 0.05 for each). Within the limitations of this experimental study, it can be concluded that for maxillofacial surgeons, it is more likely to detect condylar, orbital, and zygomatic fractures by using VR algorithm in 3D reconstruction.

Application of cone beam computed tomography for assessment of the temporomandibular joints

Radiographic examination is essential for the diagnosis and management of temporomandibular joint (TMJ) disorders. The goals of TMJ radiography are to evaluate cortical and trabecular architecture of the bony structures and confirm their integrity, to assess the extent and monitor progression of osseous changes, and to evaluate the response to treatment. Accurate evaluation of the TMJ by conventional radiography is limited by structure superimposition. Cone beam computed tomography (CBCT) provides high-resolution multiplanar images and delivers substantially lower radiation dose, compared with multislice CT. CBCT allows examination of TMJ anatomy without superimposition and distortion to facilitate analysis of bone morphology, joint space and dynamic function in all three dimensions. This article will describe the role of CBCT imaging for the assessment of the TMJ osseous structures and present typical appearances of common pathological conditions of the TMJ.

Diagnostic accuracy of cone beam computed tomography and conventional multislice spiral tomography in sheep mandibular condyle fractures

OBJECTIVES

the aim of this study was to compare diagnostic accuracy of cone beam CT (CBCT) and multislice CT in artificially created fractures of the sheep mandibular condyle.

METHODS

63 full-thickness sheep heads were used in this study. Two surgeons created the fractures, which were either displaced or non-displaced. CBCT images were acquired by the NewTom 3G CBCT scanner (NIM, Verona, Italy) and CT imaging was performed using the Toshiba Aquillon multislice CT scanner (Toshiba Medical Systems, Otawara, Japan). Two-dimensional (2D) cross-sectional images and three-dimensional (3D) reconstructions were evaluated by two observers who were asked to determine the presence or absence of fracture and displacement, the type of fracture, anatomical localization and type of displacement. The naked-eye inspection during surgery served as the gold standard. Inter- and intra-observer agreements were calculated with weighted kappa statistics. The receiver operating characteristics (ROC) curve analyses were used to compare statistically the area under the curve (AUC) of both imaging modalities.

RESULTS

kappa coefficients of intra- and interobserver agreement scores varied between 0.56 - 0.98, which were classified as moderate and excellent, respectively. There was no statistically significant difference between the imaging modalities, which were both sensitive and specific for the diagnosis of sheep condylar fractures.

CONCLUSIONS

this study confirms that CBCT is similar to CT in the diagnosis of different types of experimentally created sheep condylar fractures and can provide a cost- and dose-effective diagnostic option.

Interventions for the treatment of fractures of the mandibular condyle

BACKGROUND

Fractures of the condylar process account for between 25% and 35% of all mandibular fractures. Treatment options for fractures of the condyles consist of either the closed method or by open reduction with fixation. Complications may be associated with either treatment option; for the closed approach these can include malocclusion, particularly open bites, reduced posterior facial height and facial asymmetry in addition to chronic pain and reduced mobility. A cutaneous scar and temporary paralysis of the facial nerve are not infrequent complications associated with the open approach. There is a lack of consensus currently surrounding the indications for either surgical or non-surgical treatment of fractures of the mandibular condyle.

OBJECTIVES

To evaluate the effectiveness of interventions that can be used in the treatment of fractures of the mandibular condyle.

SEARCH STRATEGY

The databases searched were: the Cochrane Oral Health Group's Trials Register (to 12th March 2010), CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE (from 1950 to 12th March 2010), and EMBASE (from 1980 to 12th March 2010). The reference lists of all trials identified were cross checked for additional trials. Authors were contacted by electronic mail to ask for details of additional published and unpublished trials. There were no language restrictions and several articles were translated.

SELECTION CRITERIA

Randomised controlled trials (RCTs) which included adults, over 18 years of age, with unilateral or bilateral fractures of the mandibular condyles. Any form of open or closed method of reduction and fixation was considered.

DATA COLLECTION AND ANALYSIS

Review authors screened trials for inclusion. Extracted data were to be synthesised using the fixed-effect model but if substantial clinical diversity was identified between the studies we planned to use the random-effects model with studies grouped by action and we would explore the heterogeneity between the included studies. Mean differences were to be calculated for continuous outcomes and risk ratios for dichotomous outcomes together with their 95% confidence intervals.

MAIN RESULTS

No high quality evidence matching the inclusion criteria was identified.

AUTHORS' CONCLUSIONS

No high quality evidence is available in relation to this review question and no conclusions could be reached about the effectiveness or otherwise of the two interventions considered in this review. A need for further well designed randomised controlled trials exists. The trialists should account for all losses to follow-up and assess patient related outcomes. They should also report the direct and indirect costs associated with the interventions.

Evaluation of simulated bone lesion in the head of the mandible by using multislice computed tomography

Conventional radiography has shown limitation in acquiring image of the ATM region, thus, computed tomography (CT) scanning has been the best option to the present date for diagnosis, surgical planning and treatment of bone lesions, owing to its specific properties. Objective: The aim of the study was to evaluate images of simulated bone lesions at the head of the mandible by multislice CT. Material and methods: Spherical lesions were made with dental spherical drills (sizes 1, 3, and 6) and were evaluated by using multislice CT (64 rows), by two observers in two different occasions, deploying two protocols: axial, coronal, and sagittal images, and parasagittal images for pole visualization (anterior, lateral, posterior, medial and superior). Acquired images were then compared with those lesions in the dry mandible (gold standard) to evaluate the specificity and sensibility of both protocols. Statistical methods included: Kappa statistics, validity test and chi-square test. Results demonstrated the advantage of associating axial, coronal, and sagittal slices with parasagittal slices for lesion detection at the head of the mandible. Results: There was no statistically significant difference between the types of protocols regarding a particular localization of lesions at the poles. Conclusions: Protocols for the assessment of the head of the mandible were established to improve the visualization of alterations of each of the poles of the mandible's head. The anterior and posterior poles were better visualized in lateral-medial planes while lateral, medial and superior poles were better visualized in the anterior-posterior plane.

Validity of single- and multislice CT for assessment of mandibular condyle lesions

OBJECTIVES

The purpose of this study was to evaluate and to compare the validity of the different CT image protocols (single- and multislice CT) in the analysis of simulated mandibular condyle lesions.

METHODS

Simulated lesions were created in 15 dry mandibles using a dental round burr. The mandibles were then submitted to a single slice CT, and the same specimens were subsequently submitted to a multislice CT. The analysis was performed by two previously calibrated examiners in four protocols: (1) single slice-axial, (2) multislice-axial, (3) single slice-axial/multiplanar reconstructed (MPR) and (4) multislice-axial/MPR. The examiners evaluated the absence or presence of bony destruction and their localization in each protocol, considering also some bony erosion caused by its reabsorption. Statistical analysis was carried out using validity and chi(2) tests to compare the protocols.

RESULTS

Protocol 1 presented the lowest validity values (62.7%). The validity of Protocols 2 and 3 was 66.2% and 72.7%, respectively. The highest value of validity was 93.1% and corresponded to Protocol 4.

CONCLUSIONS

All CT-imaging protocols were considered accurate for mandibular condyle lesions assessment. The association of axial with MPR images using multislice CT demonstrated highest accuracy. A new imaging protocol was established for diagnosis of these lesions.

Computed tomography imaging findings of simultaneous bifid mandibular condyle and temporomandibular joint ankylosis: case report

Bifid mandibular condyle is an uncommon entity described in the literature as having a controversial etiology. Despite the absence of clinical symptomatology, the radiologist must be aware and should have some knowledge of this abnormality, as well its implications regarding functional and morphological changes. TMJ ankylosis is a disabling disease with involvement of the mandibular condyle, articular fossa and base of the skull. The association of bifid condyle with temporomandibular joint ankylosis is rare and must be carefully evaluated. The purpose of this paper is to report a case of simultaneous bifid mandibular condyle and temporomandibular joint ankylosis and to describe its computed tomography imaging findings.

Imaging of maxillofacial trauma: Evolutions and emerging revolutions

The aim of diagnostic imaging for maxillofacial trauma is to provide additional information that can positively influence medical or surgical patient management. Current advances in diagnostic imaging have come from the confluence of 3 driving forces: (1) the demand from clinicians to enhance and expand their diagnostic abilities; (2) the development of new theoretical concepts by basic scientists; and (3) the application of concepts by engineers and manufacturers to provide increasingly sophisticated imaging capabilities. The role of imaging within the health care environment is, however, also buffeted by the complex, sometimes competing, interactions of external social, political, economic, and technological pressures at the national, regional, and local levels. The purposes of this review are to provide a perspective on current imaging modalities used for maxillofacial trauma and to provide an insight into the influences, both technologic and external, on future developments and applications.