Prospective comparison of panoramic tomography (zonography) and helical computed tomography in the diagnosis and operative management of mandibular fractures

"Air Sign" in Misdiagnosed Mandibular Fractures Based on CT and CBCT Evaluation

BACKGROUND

Diagnostic errors constitute one of the reasons for the improper and often delayed treatment of mandibular fractures. The aim of this study was to present a series of cases involving undiagnosed concomitant secondary fractures in the mandibular body during preoperative diagnostics. Additionally, this study aimed to describe the "air sign" as an indirect indicator of a mandibular body fracture.

METHODS

A retrospective analysis of CT/CBCT scans conducted before surgery was performed on patients misdiagnosed with a mandibular body fracture within a one-year period.

RESULTS

Among the 75 patients who underwent surgical treatment for mandibular fractures, mandibular body fractures were missed in 3 cases (4%) before surgery. The analysis of CT/CBCT before surgery revealed the presence of an air collection, termed the "air sign", in the soft tissue adjacent to each misdiagnosed fracture of the mandibular body.

CONCLUSIONS

The "air sign" in a CT/CBCT scan may serve as an additional indirect indication of a fracture in the mandibular body. Its presence should prompt the surgeon to conduct a more thorough clinical examination of the patient under general anesthesia after completing the ORIF procedure in order to rule-out additional fractures.

Surgical Guide Splint Fabrication via Virtual Surgical Planning for Complex Mandible Fractures in the Trauma Setting

INTRODUCTION

In cases of significantly displaced or comminuted mandible fractures, surgical guide splints can be developed to create the normal preinjury occlusion rather than placing patients in maxillomandibular fixation. Standard fracture fixation involves bending of plates intraoperatively based on surgeon-constructed dental splints which is prone to error.

METHODS

A 38-year-old male experienced a gunshot wound to the face that resulted in mandibular angle fractures bilaterally causing severely deranged occlusion and free-floating anterior mandible segment. Virtual surgical planning (VSP) software was used to recreate the injury-induced anatomy and anticipated postoperative anatomy. It also provided a surgical guide splint and a framework to preoperatively bend reconstruction plates to assist in achieving proper occlusion.

RESULTS

He underwent open reduction internal fixation of comminuted mandible fractures with lingual guide splint placement 10 days after injury. Following lingual splint application, the reconstruction plate was applied from angle to angle. The lingual splint was maintained for 3 weeks postoperatively to support the stabilization, and he was able to tolerate a regular diet and showed no evidence of wound breakdown.

DISCUSSION

Virtual surgical planning has had important implications in craniofacial surgery, orthognathic surgery, maxillomandibular reconstruction, and orbital reconstruction after tumor resection, temporomandibular joint surgery, and others. However, there have only been isolated reports describing the role of VSP in the facial trauma setting. In this technical study, the authors demonstrate the benefits of VSP and surgical guide splinting in trauma settings.

Diagnosis of split fractures of the mandible in adults

BACKGROUND

Mandibular split fractures, in which the fracture occurs exclusively in the posterior wall, are uncommon. This study aimed to enhance clinicians' understanding of mandibular split fractures and offer insights for future research.

METHODS

This study included six patients who visited our hospital between January 2020 and June 2023 and were diagnosed with mandibular split fractures. We retrospectively collected data from patients' medical records on their age, sex, symptoms, mechanism, impact site, associated injuries, and treatment method, as well as the location, pattern, and number of fractures observed on computed tomography (CT) and panoramic images. The frequency of split fractures among all mandibular fractures was calculated.

RESULTS

The six patients included three men (50%) and three women (50%), ranging in age from 20 to 71 years (mean age, 49.8 years). The split fractures were located in the symphysis in one patient (16.7%), symphysis to parasymphysis in two patients (33.3%), parasymphysis in one patient (16.7%), and parasymphysis to the body in two patients (33.3%). Four patients (66.7%) had condylar head fractures, while two patients (33.3%) had single split fractures. The mechanism of trauma was a slip-down incident in four cases (66.7%), while two cases (33.3%) were caused by motorcycle traffic accidents. Four patients (67%) underwent intermaxillary fixation, while two patients (33%) improved with conservative treatment. Split fractures were diagnosed in all six patients on CT, whereas the fracture line was not clearly visible on panoramic images. Mandibular split fractures accounted for 5.6% of all mandibular fractures.

CONCLUSION

This study provides insights into the clinical characteristics of rare mandibular split fractures and the diagnostic imaging findings. Furthermore, CT scans and three-dimensional image synthesis-instead of panoramic images-may be essential for accurately diagnosing mandibular fractures, including mandibular split fractures, in the future.

Retrospective Evaluation of Maxillofacial Fractures With Cone-Beam Computed Tomography

ÖZ Amaç: Bu çalışmanın amacı maksillofasiyal bölgede meydana gelen fraktürlerin yaş ve cinsiyete göre dağılımlarını, lokalizasyonlarını, sayısını, deplasman varlığını, radyolojik özelliklerini Konik Işınlı Bilgisayarlı Tomografi (KIBT) ile retrospektif olarak değerlendirmektir. Gereç ve Yöntemler: Zonguldak Bülent Ecevit Üniversitesi Diş Hekimliği Fakültesi, Ağız Diş ve Çene Radyolojisi Anabilim Dalı’na 2019 ve 2021 yılları arasında travma nedeniyle başvuran 84 hastadan alınan KIBT görüntüleri retrospektif olarak incelenmiştir. Yaş, cinsiyet, fraktür lokalizasyonu, fraktürlerde deplasman varlığı kayıt altına alındı. İstatistiksel analiz için tüm hasta grubuna tanımlayıcı ve frekans analizleri uygulanırken, hastaların yaş ve cinsiyetlerini; fraktür hattı ve fraktür bölgesi ile karşılaştırırken ki-kare testi uygulandı. Bulgular: 60 erkek 24 kadın hasta (E/K, 2,5/1) olmak üzere toplam 84 hastanın maksillofasiyal travma nedeniyle KIBT görüntüsü incelendi. Çalışmada incelenen hasta grubunun yaşları 6 ve 72 arasında değişmekte olup yaş ortalaması 33.17±1.48 olarak belirlendi. Farklı etiyolojik nedenlerden kaynaklı çeşitli lokalizasyonlarda meydana gelen 116 fraktür hattı sayısı radyolojik olarak tespit edildi. İncelenen tüm fraktürlerin 73’ünde deplasman izlenirken kalan 43 fraktür hattında deplasman görülmedi. Meydana gelen fraktürler en sık angulus mandibulada (%22,61:n=19) tespit edildi. En az fraktür mandibula ramus (%3,57; n=3) ve koronoid proseste (%3,57; n=3) görüldü. Sonuçlar: Fraktür hatlarının varlığının, lokalizasyonlarının ve kırık parçalarının yer değişiminin doğru radyografik teknikler aracılığıyla tespit edilmesi, gerekli tedavi prosedürlerinin uygulanması açısından önem taşımaktadır. İki boyutlu radyografilerin kullanımının yetersiz kaldığı durumlarda KIBT gibi üç boyutlu görüntüleme yöntemleri tercih edilmelidir. Anahtar Kelimeler: Konik Işınlı Bilgisayarlı Tomografi, Fraktür, Mandibula, Teşhis

ACR Appropriateness Criteria® Imaging of Facial Trauma Following Primary Survey

Maxillofacial trauma patients comprise a significant subset of patients presenting to emergency departments. Before evaluating for facial trauma, an emergency or trauma physician must perform a primary survey to ensure patient stabilization. Following this primary survey, this document discusses the following clinical scenarios for facial trauma: tenderness to palpation or contusion or edema over frontal bone (suspected frontal bone injury); pain with upper jaw manipulation or pain overlying zygoma or zygomatic deformity or facial elongation or malocclusion or infraorbital nerve paresthesia (suspected midface injury); visible nasal deformity or palpable nasal deformity or tenderness to palpation of the nose or epistaxis (suspected nasal bone injury); and trismus or malocclusion or gingival hemorrhage or mucosal hemorrhage or loose teeth or fractured teeth or displaced teeth (suspected mandibular injury). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Re-evaluating the need for orthopantomography in the management of mandibular trauma: is computed tomography enough?

BACKGROUND

Mandibular fractures are frequent indications for computed tomography (CT) and orthopantomography (OPG) scans in emergency rooms. Numerous studies found CT to have higher sensitivity and enhanced accuracy compared to OPG in diagnosing mandible fractures. Controversy exists regarding additional need for OPG when evaluating dental trauma. This study investigates whether OPG adds diagnostic value to CT in mandibular trauma and whether additional OPG significantly alters management.

METHODS

A retrospective chart review identified 100 patients ≥ 18 years of age with known mandibular trauma who received CT and OPG in the emergency department between May 2015 and January 2020. All patients demonstrated a fracture in at least one study. CT and OPG studies were anonymized and randomized. A single attending surgeon evaluated mandible fracture and dental trauma characteristics and subsequently compared findings.

RESULTS

One hundred patient CT and OPG scans were reviewed. CT detected mandible fractures in all patients and OPG detected fractures in 93% (p = 0.01). Twenty-eight patients had different findings between scans. CT demonstrated 1 or more additional fracture(s) than OPG in 20 patients and dental trauma not seen on OPG in 4. OPG detected 1 fracture and no dental trauma that was not seen on CT. CT drove treatment-determining differences in 17 cases and OPG in 0 cases.

CONCLUSIONS

CT appears efficacious in detecting clinically significant mandible fractures and dental trauma with little additional benefit from OPG in emergency settings. Helical CT may be the only imaging necessary in evaluating patients with such trauma.

Comparing diagnosis of midfacial fractures by radiologists and plastic surgeons

BACKGROUND

Clinicians who manage facial fractures often rely on radiologist interpretations to help with assessment and management. Among treating physicians, facial fractures are categorized into clinically relevant patterns of injury. On the other hand, while radiologists are unsurpassed at identifying individual breaks in the bone, larger fracture patterns are not always conveyed in radiology reports.

PURPOSE

This study aims to assess the frequency with which the terminology describing midfacial fracture patterns is concordant among radiologists and treating clinicians.

METHODS

The authors identified patients with different patterns of midfacial injury including Le Fort I, Le Fort II, Le Fort III, naso-orbito-ethmoid (NOE), and zygomaticomaxillary complex (ZMC) fractures. Plastic surgery consult notes and radiological imaging reports were reviewed for concordance in documentation of injury patterns. Identification of individual fractures consistent with the diagnosed fracture pattern was also recorded.

RESULTS

Radiologists were noted to be highly successful in describing individual fractures of the facial bones, identifying at least two defining components of a fracture pattern in 96% of Le Fort, 88% of NOE, and 94% of ZMC injuries. However, when injury patterns were considered, only 32% of Le Fort, 28% of ZMC, and 6% of NOE fractures were explicitly identified in radiology reports.

CONCLUSIONS

Radiologists are highly skilled in discerning individual fractures in facial trauma cases. However, less reliability was seen in the identification of fracture patterns in midfacial injury, with particular weaknesses in descriptions of NOE and ZMC fractures. This data suggests that greater focus on patterns of midfacial injury would improve the clinical applicability of radiological reports.

A new classification of mandibular fractures

There is no accepted method of reporting mandibular fracture that reflects incidence, treatment and outcome for individual cases. As most series include anatomical site only for all fractures, the aim was to establish a new method to report fractures based on a systematic review of the literature and an internal audit. The classification proposed is: Class I; condyle, II; angle, IIc; II+condyle, III; body/symphysis, IIIc; III+condyle, IV; multiple fractures not including condyle, IVc; IV+condyle, V; bilateral condyle±other fracture(s). A total of 10,971 adult and 914 paediatric cases were analyzed through systematic review, and 833 from the regional audit. Only 32% (14/44) of reported series could be reclassified which, when added to the audit data, showed Class IV was most common (29%), with similar proportions of Class III, Class IIIc and Class II (18-23%). External validation (literature review) in terms of treatment and outcome was non-informative, but the internal validation (audit) demonstrated an increasing requirement for adding maxillomandibular fixation (MMF) to open reduction and internal fixation (ORIF) as class increased. The heterogeneity of data reporting found in the systematic review confirms the need for a classification such as this, likely to enhance comparison of varying management protocols.

Fractures of the mandible: Epidemiological study of 519 Nigerian cases

Background:

Epidemiological studies despite their limitations provide information that is useful for the formulation of effective and efficient injury prevention strategies.

Aim:

The aim is to carry out epidemiology study of mandibular fracture in a Nigerian population.

Setting:

Department of Oral and Maxillofacial Surgery, Ahmadu Bello University Teaching Hospital, Shika-Zaria, Nigeria.

Materials and Methods:

A retrospective observational study was carried out at the Ahmadu Bello University Teaching Hospital, Shika-Zaria. Data retrieved from patients’ case notes and operating records were subjected to statistical analysis involving frequencies (count, percent), measures of central tendency (mean), and measures of dispersion (standard deviation) using Statistical Package for Social Sciences (SPSS) version 16 (SPSS Inc., Chicago, IL). Mandibular fracture was classified based on sites, and patients’ socioeconomic status was classified based on United Kingdom National Statistics Socio-economic Classification (NS-SEC, 2010).

Results:

There were 466 (89.9%) males and 53 (10.1%) females. Based on Socio-economic Classification (NS-SEC, 2010), there was a preponderance of analytical class 6 (n = 217; 54.9%) and 8 (n = 127; 32.2%). Road traffic–related accident (n = 385; 74.2%) was the most common aetiological factor, and a total of 215 (41.4%) patients had a record of loss of consciousness. The mandibular body (n = 225; 32.0%) followed by the parasymphyseal (n = 187; 26.6%) regions were the most fractured sites. Closed-reduction technique was the predominant treatment modality.

Conclusions:

A road traffic accident was the most common aetiological factor for mandibular fracture, and the mandibular body had the highest frequency of fractures. Measures aimed at injury prevention should be continually reviewed and updated to limit the morbidity and economic burden on individuals.

Postoperative CT of the Mandible Following Trauma: Review of Normal Appearances and Common Complications

RATIONALE AND OBJECTIVES

Surgeons aim to restore occlusion and jaw function to baseline status for patients with mandibular fractures using either closed treatment or reduction and fixation.

MATERIALS AND METHODS

Occlusion is defined as the relationship between the maxillary and mandibular teeth as they approach each other.

RESULTS

Radiologists should be familiar with the goals of repair to help identify which treatment is adequate as well as to diagnose potential complications. Some of the more common complications encountered are infection, nonunion or malunion, and malocclusion.

CONCLUSION

We provide a comprehensive review of both the desired and untoward CT findings after surgical repair of traumatic mandibular injuries.

Multidetector CT of Mandibular Fractures, Reductions, and Complications: A Clinically Relevant Primer for the Radiologist

After the nasal bones, the mandible is the second most common site of facial fractures, and mandibular fractures frequently require open reduction. In the trauma injury setting, multidetector computed tomography (CT) has become the cornerstone imaging modality for determining the most appropriate treatment management, fixation method, and surgical approach. Multidetector CT is also used to assess the adequacy of the reduction and evaluate potential complications in the postoperative period. For successful restoration of the mandible's form and function, as well as management of posttraumatic and postoperative complications, reconstructive surgeons are required to have a detailed understanding of mandibular biomechanics, occlusion, and anatomy. To provide added value in the diagnosis, treatment planning, and follow-up of mandibular fractures, radiologists should be aware of these concepts. Knowledge of the techniques commonly used to achieve occlusal and anatomic reduction and of the rationale behind the range of available treatment options for different injury patterns-from isolated and nondisplaced fractures to multisite and comminuted fractures-also is essential. This article focuses on the use of multidetector CT for pre- and postoperative evaluation of mandibular fractures and outlines fundamental concepts of diagnosis and management-beginning with an explanation of common fracture patterns and their biomechanical underpinnings, and followed by a review of the common postoperative appearances of these fractures after semirigid and rigid fixation procedures. Specific considerations regarding fractures in different regions of the tooth-bearing and non-tooth-bearing mandible and the unique issues pertaining to the edentulous atrophic mandible are reviewed, and key features that distinguish major from minor complications are described. (©)RSNA, 2016.

Imaging in traumatic mandibular fractures

A fracture of the mandible is a common trauma presentation amongst young males and represents one of the most frequently encountered fractured bones within the viscerocranium. Historically, assault was the dominant contributing factor but now due to the increased number of vehicles used per capita, motor vehicle accidents are the primary cause. Mandibular fractures can be classified anatomically, by dentition, by muscle group and by severity. The fracture may also be closed, open, comminuted, displaced or pathological. It is important that the imaging modality used identifies the classification as this will decide definitive treatment. X-ray projections have typically been used to detect a mandibular fracture, but are limited to an anteroposterior (AP), lateral and oblique view in an unstable trauma patient. These views are inadequate to detail the level of fracture displacement and show poor detail of the condylar region. Computer tomography (CT) is the imaging modality of choice when assessing a traumatic mandibular injury and can demonstrate a 100% sensitivity in detecting a fracture. This is through use of a multidetector-row CT, which reduces motion blur and therefore produces accurate coronal and sagittal reconstructions. Furthermore, reconstructive three-dimensional CT images gained from planar views, allows a better understanding of the spatial relationship of the fracture with other anatomical landmarks. This ensures a better appreciation of the severity and classification of a mandibular fracture, which therefore influences operative planning. Ultrasound is another useful modality in detecting a mandibular fracture when the patient is too unstable to be transferred to a CT scanner. The sensitivity however is less in comparison to a CT series of images and provides limited detail on the fracture pattern. Magnetic resonance imaging demonstrates use in assessing soft tissue injury of the temporomandibular joint but this is unlikely to be of priority when initially assessing a trauma patient.

Mandible Fractures

Mandible fractures account for a significant portion of maxillofacial injuries and the evaluation, diagnosis, and management of these fractures remain challenging despite improved imaging technology and fixation techniques. Understanding appropriate surgical management can prevent complications such as malocclusion, pain, and revision procedures. Depending on the type and location of the fractures, various open and closed surgical reduction techniques can be utilized. In this article, the authors review the diagnostic evaluation, treatment options, and common complications of mandible fractures. Special considerations are described for pediatric and atrophic mandibles.

CT sinus and facial bones reporting by radiographers: findings of an accredited postgraduate programme

OBJECTIVES

The aim of this study was to compare the observer performance of a cohort of radiographers in reporting CT sinus and facial bone investigations against a reference standard and alternative comparator of summary data from peer-reviewed literature.

METHODS

The participants (n = 6) completed a 9-month part-time distance learning training programme prior to reporting an examination bank (n = 25 cases) from a retrospectively collected and anonymized digital imaging and communications in medicine archive of CT examinations with referral histories and clinical reports. A literature search was performed to identify an additional alternative comparison reference standard from studies reporting observer performance data in CT sinus and facial bone investigations of both trauma and sinus pathology (target conditions). The data analyses used to measure observer performance and determine differences between the cohort and the reference standards used statistical assessment models including accuracy, sensitivity, specificity, kappa (κ) and summary receiver-operating characteristic curves with estimated area under the curve (AUC).

RESULTS

The cohort of radiographer sensitivity was 97.5%, specificity 93.6% and accuracy 95%, with p < 0.000, and a κ = 0.9121 score of agreement. The mean radiographer AUC was 0.9822. The summary reported data of the alternative literature reference standard comparator were AUC 0.9533 for sinus and 0.9374 for trauma.

CONCLUSIONS

The results suggest that this cohort of radiographers at the end of a period training in CT sinus and facial bones are able to clinically report comparably high standards.

Evidence-based medicine: Mandible fractures

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Describe the anatomy and subunits of the mandible. 2. Review the cause and epidemiology of mandible fractures. 3. Discuss the preoperative evaluation and diagnostic imaging. 4. Understand the principles and techniques of mandible fracture reduction and fixation.

SUMMARY

The management of mandibular fractures has undergone significant improvement because of advancements in plating technology, imaging, and instrumentation. As the techniques in management continue to evolve, it is imperative for the practicing physician to remain up-to-date with the growing body of scientific literature. The objective of this Maintenance of Certification article is to present a review of the literature so that the physician may make treatment recommendation based on the best evidence available. Pediatric fractures have been excluded from this article.

Surgical perspectives in craniofacial trauma

Knowledge of relevant anatomy and underlying mechanisms of traumatic injury is essential for understanding the radiologic findings in craniofacial trauma and their clinical importance. Craniofacial anatomy is diverse, and as a result of this anatomic diversity, physicians from numerous different specialties scrutinize similar imaging sets, looking for different pathologic abnormalities within the same anatomic regions. Radiologists familiar with the chief concerns of this anatomically diverse region can help expedite the decision-making process by keeping those concerns in mind when they report their findings. This review provides an overview of situations wherein surgical management may be indicated.

Diagnostic efficacy of cone-beam computed tomography for mandibular fractures

OBJECTIVE

The aim of the study was to determine the clinical efficacy of maxillofacial cone-beam computed tomography (CBCT) for the diagnosis of suspected mandibular fractures and to evaluate whether findings would lead to a change in treatment.

STUDY DESIGN

CBCT imaging was performed for 164 patients with suspected mandibular fractures (231 sites) but equivocal clinical and radiological findings (conventional radiography). Images were interpreted by oral and maxillofacial surgeons and treatment decisions based on pre and postimaging were compared. Linear regression analyses were performed.

RESULTS

For 63.2% of sites (n = 146) the suspected diagnosis was confirmed by CBCT (P < .0001; R(2) = 0.93). For 4.33% of sites (n = 10) no fracture was identified. Additional fractures were identified in 17.75% (n = 41) and additional infractures in 14.72% (n = 34). The treatment plan was altered for 9.52% of sites (n = 22).

CONCLUSIONS

CBCT imaging of suspected mandibular fractures resulted in a change in the treatment plan in 9.52%.

Mandibular fracture patterns consistent with posterior maxillary fractures involving the posterior maxillary sinus, pterygoid plate or both: CT characteristics

OBJECTIVES

The aim of this study was to determine the incidence of posterior maxillary fractures involving the posterior maxillary sinus wall, pterygoid plate or both, unrelated to major midface fractures in patients with mandibular fractures, and to characterize associated fractures.

METHODS

A CT study was performed in patients with mandibular fractures to identify posterior maxillary fractures. Patients aged under 16 years, those with mandibular fractures involving only dentoalveolar components and those with concurrent major midfacial fractures were excluded.

RESULTS

13 (6.7%) of 194 patients with mandibular fractures also had posterior maxillary fractures (case group). The injury pattern correlated with the external force directed to the lateral side of the mandible (p < 0.001), alcohol consumption (p = 0.049), the presence of multifocal fractures (p = 0.002) and the fracture regions in the symphysis/parasymphysis (p = 0.001) and the angle/ramus (p = 0.001). No significant difference between the case and non-case groups was seen for age, sex or cause of trauma. Non-displaced fractures in the ipsilateral posterior mandible occurred with significant frequency (p = 0.001) when the posterior maxillary fractures involved only the sinus.

CONCLUSIONS

Mandibular fractures accompanied by posterior maxillary fractures are not rare. The finding of a unilateral posterior maxillary fracture on CT may aid the efficient radiological examination of the mandible based on possible patterns of associated fractures, as follows: in the ipsilateral posterior region as a direct fracture when the impact is a medially directed force, and in the symphysis/parasymphysis or contralateral condylar neck as an indirect fracture.

Late reconstruction of condylar neck and head fractures

Condyle fractures are a common injury, but only a few of these injuries require immediate or late reconstruction. The complications that most frequently necessitate condylar reconstruction include proximal segment degeneration, malunion, and ankylosis. Costochondral grafts and total joint prostheses, both stock and custom, remain the most common methods of reconstruction. Reconstruction plates with condylar extensions should only be used temporarily as an unacceptable number cause serious complications. Distraction osteogenesis may have an occasional role in reconstructing the posttraumatic condyle.

A review of mandibular angle fractures

AFTER STUDYING THIS ARTICLE, THE READER WILL BE ABLE TO: (1) review the incidence and etiology of mandibular angle fractures; (2) gain an understanding of patient evaluation and general management principles; and (3) discuss indications and available techniques for management of mandibular angle fractures. Angle fractures represent the highest percentage of mandibular fractures. Two of the most common causes of mandibular angle fractures are motor vehicle accidents and assaults or altercations. With any patient who has sustained facial trauma, a thorough history and comprehensive physical examination centering on the head and neck region as well as proper radiological assessment are essential. These elements are fundamental in establishing a diagnosis and developing an appropriate treatment plan for any mandibular fracture.

The imaging of maxillofacial trauma and its pertinence to surgical intervention

Maxillofacial skeletal injuries account for a large proportion of emergency department visits and often result in surgical consultation. Although many of the principles of detection and repair are basic, the evolution of technology and therapeutic strategies has led to improved patient outcomes. This article aims to provide a review of the imaging aspects involved in maxillofacial trauma and to delineate its relevance to management.

Diagnostic performance of dental students in identifying mandibular condyle fractures by panoramic radiography and the usefulness of reference images

Purpose

The purpose of this study was to evaluate the diagnostic performance of dental students in detection of mandibular condyle fractures and the effectiveness of reference panoramic images.

Materials and Methods

Forty-six undergraduates evaluated 25 panoramic radiographs for condylar fractures and the data were analyzed through receiver operating characteristic (ROC) analysis. After a month, they were divided into two homogeneous groups based on the first results and re-evaluated the images with (group A) or without (group B) reference images. Eight reference images included indications showing either typical condylar fractures or anatomic structures which could be confused with fractures. Paired t-test was used for statistical analysis of the difference between the first and the second evaluations for each group, and student's t-test was used between the two groups in the second evaluation. The intra- and inter-observer agreements were evaluated with Kappa statistics.

Results

Intra- and inter-observer agreements were substantial (k=0.66) and moderate (k=0.53), respectively. The area under the ROC curve (Az) in the first evaluation was 0.802. In the second evaluation, it was increased to 0.823 for group A and 0.814 for group B. The difference between the first and second evaluations for group A was statistically significant (p<0.05), however there was no statistically significant difference between the two groups in the second evaluation.

Conclusion

Providing reference images to less experienced clinicians would be a good way to improve the diagnostic ability in detecting condylar fracture.

Major mandibular surgical procedures as an indication for intraoperative imaging

PURPOSE

This study investigated 3-dimensional (3D) imaging with intraoperative cone beam computed tomography (CBCT) in major mandibular reconstruction procedures.

PATIENTS AND METHODS

The study group was comprised of 125 patients (83 males, 42 females) admitted for surgical treatment of the mandible. The patients ranged in age from 3 months to 91 years (average age, 40.72 +/- 22.843 years). Surgical procedures of the mandible were subdivided into repair of body fractures (17 patients), angle fractures (21 patients), condylar fractures (14 patients), and multiple fractures (30 patient). In addition, the study group included 21 patients undergoing orthognatic surgery and 22 undergoing reconstructive surgery on the mandible. Intraoperatively, 3D images were generated with a mobile CBCT scanner (Arcadis Orbic 3D; Siemens Medical Solutions, Erlangen, Germany).

RESULTS

During open reduction of mandibular fractures, not all fracture sites can be readily exposed for direct visual control. For example, the lingual cortical bone of the mandible is difficult to assess intraoperatively. This structure and others can be effectively visualized using the 3D mode of CBCT. Furthermore, screw placement can be evaluated, specifically in insertions near the alveolar nerve. The intraoperative acquisition of the data sets is uncomplicated, and the image quality is sufficient to allow evaluation of the postoperative result in all cases.

CONCLUSION

Intraoperative CBCT has proven to be a reliable imaging technique for providing visual control during major mandibular procedures.

Incidence and characterization of unifocal mandible fractures on CT

BACKGROUND AND PURPOSE

Conventional thinking among radiologists is that the mandible acts as a closed "ring" that needs to fracture at 2 points, though the frequency of multiple mandible fractures has been reported to be only as high as 67%. However, many of these studies did not use CT to confirm the presence of suggested fractures and excluded nondisplaced fractures. The purpose of this study was to determine the incidence of unifocal mandibular fractures on the basis of detection with dedicated facial bone CT scans and to characterize these fractures.

MATERIALS AND METHODS

We retrospectively reviewed the imaging reports of patients during a 3-year period to identify those who had mandible fractures documented on dedicated facial bone CT scans. The incidence of unifocal fractures was determined, the unifocal fractures were further subcategorized, and any derangements of the temporomandibular joints were also evaluated.

RESULTS

One hundred two patients met the inclusion criteria. The incidence of unifocal mandible fractures was 42% (43/102). Three unifocal fracture patterns identified were the following: simple fractures (25/42, 58%), comminuted fractures (11/42, 26%), and fractures associated with condylar subluxations (7/42, 16%). Most fractures had none to mild displacement or distraction.

CONCLUSION

Unifocal mandible fractures occur with greater frequency than anticipated by most radiologists. This may be due to the somewhat dynamic nature of the mandibular "ring," which includes the temporomandibular joints, though joint derangements evident on CT occur in the minority of cases.

Posttraumatic Mandibular Deformities

In covering the Emergency Department, the Plastic Surgeon can be faced with the mandibular fracture patient. Although the timely repair of the fracture usually leads to normal function and appearance, occasionally the surgeon is faced with the untoward sequelae of the mandible fracture. Post-traumatic mandibular deformities include non-union, malunion, malocclusion, TMJ dysfuction, and facial asymmetry. The difficulty in treatment of these deformities can be compounded by edentulous mandibles, substance abuse, and approach controversies such as the timing of the repair and surgical versus non-surgical management. Knowledge of the post-traumatic mandibular deformities by the treating physician not only assists in their management but may also allow for their prevention.

Management of Mandible Fractures

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Review the incidence and etiology of mandible fractures. 2. Discuss indications and techniques for closed and open treatment of mandible fractures. 3. Review complications of mandible fractures.

BACKGROUND

Mandible fractures are among the most common types of facial fractures treated by plastic surgeons. They must be managed carefully to maintain the function of the mandible, reestablish proper occlusion, and minimize secondary complications.

METHODS

Current methods of management include combinations of soft diet, intermaxillary fixation, open reduction with plate fixation, and, rarely, external fixation.

RESULTS

Decision-making depends on the age of the patient, type of fracture identified, and concomitant medical conditions or injuries.

CONCLUSION

The authors review the diagnosis and current trends in management of mandible fractures.

Condylar Fracture Repair: Use of the Endoscope to Advance Traditional Treatment Philosophy

Traditional treatment of subcondylar fractures with maxillomandibular fixation often results in a malreduction and significant functional and aesthetic sequelae, including facial asymmetry, decreased jaw opening, and potential for late derangements of the temporomandibular joint. When used selectively, based on preoperative CT scans, the endoscopic technique will reliably restore condylar anatomy in nearly 95% of patients, thus obviating the consequences of malunion. Furthermore, unlike traditional open techniques no significant facial scarring or permanent facial nerve palsies have resulted. Thus, the authors strongly advocate endoscopic repair of adult condylar neck and subcondylar fractures that demonstrate displacement or dislocation and have adequate proximal bone stock to accept miniplate fixation.

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.

The Identification of Mandible Fractures by Helical Computed Tomography and Panorex Tomography

The introduction of computed tomography (CT) in 1972 revolutionized the radiographic evaluation of patients who have experienced trauma. However, panoramic tomography (PT) continued to be superior in sensitivity to CT in the identification of mandible fractures and has been considered the gold standard for the past 3 decades. In 1989, a faster, higher-resolution spiral or helical CT (HCT) became widely available, and its efficacy in multiplanar evaluation and diagnosis of fractures of the upper two thirds of the face has been well established. The sensitivity of this new-generation HCT in comparison to PT in the detection of mandible fractures has not been determined. The purpose of this study was to compare the sensitivity, physician interpretation error, and interphysician agreement of HCT and PT in the identification of mandible fractures. The number and anatomical location of mandible fractures identified by HCT and PT was not significantly different. However, the number and location of 96% of fractures identified by HCT was agreed on by neuroradiologists compared with only 91% of fractures identified by PT. Furthermore, the interphysician agreement when no fracture was identified was 96% by HCT versus only 81% by PT. In conclusion, HCT has enhanced imaging quality, equivalent sensitivity in identification of fractures, decreased interpretation error, and greater interphysician agreement in the identification of mandible fractures. HCT has surpassed PT as the current gold standard for the radiographic evaluation and diagnosis of mandible fractures.

Do We Need Three-Dimensional Computed Tomography in Maxillofacial Surgery?

In a retrospective clinical study (2000-2003), 121 patients' radiographs and computed tomography scans were reviewed to establish the clinical value of three-dimensional computed tomography. Eighty patients had computed tomography scans; 48 had three-dimensional computed tomography scans for diagnosing facial fractures, 3 for diagnosing temporomandibular joint ankylosis, 1 for tumor with bone destruction, and 1 for a mandibular cyst. It is concluded that axial, coronal, and three-dimensional computed tomography is of crucial importance and should be mandatory for all suspected comminuted and displaced midface fractures instead of plain radiographs. Three-dimensional computed tomography is also recommended for comminuted mandibular fractures and temporomandibular joint ankylosis. Three-dimensional computed tomography is not recommended for the diagnosis of minimally displaced fractures.