Are Magnetic Resonance Imaging-Generated 3Dimensional Models Comparable to Computed Tomography-Generated 3Dimensional Models for Orbital Fracture Reconstruction? An In-Vitro Volumetric Analysis.

BACKGROUND: Magnetic resonance imaging (MRI) is being increasingly considered as an alternative for the evaluation and reconstruction of orbital fractures. No previous research has compared the orbital volume of an MRI-imaged, three-dimensional (3D), reconstructed, and virtually restored bony orbit to the gold standard of computed tomography (CT). PURPOSE: To measure the orbital volumes generated from MRI-based 3D models of fractured bony orbits with virtually positioned prebent fan plates in situ and compare them to the volumes of CT-based virtually reconstructed orbital models. STUDY DESIGN: This retrospective in-vitro study used CT and MRI data from adult patients with orbital trauma assessed at the Royal Brisbane and Women's Hospital Outpatient Maxillofacial Clinic from 2011 to 2012. Only those with orbital blowout fractures were included in the study. PREDICTOR VARIABLE: The primary predictor variable was imaging modality, with CT- and MRI-based 3D models used for plate bending and placement. MAIN OUTCOME VARIABLE: The primary outcome variable was the orbital volume of the enclosed 3D models. COVARIATES: Additional data collected was age, sex, and side of fractured orbit. The effect of operator variability on plate contouring and orbital volume was quantified. ANALYSES: The Wilcoxon signed rank test was used to assess differences between orbital volumes with a significance level P < .05. RESULTS: Of 11 eligible participants, six patients (four male and two female; mean age 31 ± 8.6 years) were enrolled. Two sets of six CT-based virtually restored orbits were smaller than the intact contralateral CT models by an average of 1.02 cm3 (95% CI -0.07 to 2.11 cm3; P = .028) and 0.99 cm3 (95% CI 0.07 to 1.91 cm3; P = .028), respectively. The average volume difference between the MRI-based virtually restored orbit and the intact contralateral MRI model was 0.97 cm3 (95% CI -1.08 to 1.94 cm3; P = .75). Imaging modality did affect orbital volume difference for 1 set of CT and MRI models (0.63 cm3; 95% CI -0.11 to 1.29 cm3; P = .046) but not the other (0.69 cm3; 95% CI -0.11 to 1.23 cm3; P = .075). Single operator variability in plate bending did not result in significant (P = .75) volume differences. CONCLUSIONS: MRI can be used to reconstruct orbital volume with a clinically acceptable level of accuracy.

Paediatric trauma imaging in a regional Queensland hospital: Do we need clearer guidance?

OBJECTIVE: Paediatric trauma is a major cause of morbidity and mortality in those aged 0-14. Anatomical and physiological differences require a specialised approach to paediatric trauma care. Medical imaging, particularly computed tomography (CT) scans, requires specific consideration because of the consequences of radiation exposure in the paediatric population. The present study compares current practice of CT scan ordering in paediatric trauma patients at a regional Australian hospital against consensus guidelines published in the UK. METHODS: A retrospective audit of paediatric trauma CT scans referred from the ED from May 2017 to May 2018 was completed. Details relating to CT scan ordering were reviewed and compliance with the Royal College of Radiologists Paediatric trauma protocols, was determined. Descriptive statistics and χ2 tests comparing those that met and did not meet guidelines were performed. RESULTS: A total of 71 CT scans were included with an overall compliance rate of 56.3%. Specific regional compliance was lowest with CT neck at 14%. Patients where a trauma call was initiated were more likely to receive a full body (pan) scan rather than region specific imaging. Compliance improved when paediatric team involvement was documented. CONCLUSIONS: Evidence-based guidelines for CT imaging in paediatric trauma are essential to reduce unnecessary radiation exposure for children. The present study has demonstrated that current practice has the potential to be improved and that decisions should involve a multidisciplinary team.

Investigation of Sustained BMP Delivery in the Prevention of Medication-Related Osteonecrosis of the Jaw (MRONJ) in a Rat Model.

Medication-related osteonecrosis of the jaw (MRONJ) poses an ongoing challenge for clinicians and researchers. Currently, there is a lack of preventative measures available for at-risk patients undergoing tooth extractions, especially those with prior bisphosphonate treatment due to osteoporosis or bone metastasis diagnoses. Here, these issues are addressed using a preventative tissue engineering strategy against MRONJ development. This study evaluates the efficacy of a poly(ethylene glycol)-heparin hydrogel as a tool for the delivery of arginylglycylaspartic acid (RGD) and recombinant human bone morphogenic protein-2 (rhBMP-2). Three groups of skeletally mature rats each receive two doses of intravenous zoledronic acid prior to surgery and undergo extraction of the right first mandibular molar with gingival closure. Experimental groups either have the sockets left empty, filled with hydrogel minus rhBMP-2, or filled with hydrogel plus rhBMP-2. Eight weeks postoperatively specimens are analyzed using radiological, histological, and scanning electron microscopy (SEM) techniques. µCT analysis shows increased bone formation with hydrogel/rhBMP-2 delivery compared to the empty socket. Hydrogel-treated groups display increased presence of osteocytes and increased osteoclastic action compared to the empty sockets. These results represent the first step toward improved delivery of rhBMP-2 and a potential MRONJ preventative for patients undergoing bisphosphonate treatment.

Systematic review of Australian policing interventions to reduce alcohol-related violence - A maxillofacial perspective.

Alcohol-related violence remains to be a health concern, and the oral and maxillofacial surgeons are routinely exposed to its impact on the victims and the healthcare system. At a community level, various policing interventions have been implemented to address this violent crime in and around licensed premises. Current study sought to examine the effectiveness of these interventions in Australia. Ten eligible studies, that evaluated the impact of 15 Australian policing interventions on reducing alcohol-related violence in the night-time economy, were included in this systematic review. Due to the heterogeneity of the study designs and the insufficiency of the reported data, quantitative meta-analysis of the findings was precluded. Instead, a critical narrative approach was used. Police-recorded assault rate was the primary outcome measured to assess the level of alcohol-related violence, which was influenced by the level of police duties implemented during the intervention period. The overall evidence base to support Australian policing interventions was found to be poor and was limited by the low-quality study design observed in the majority of the included studies. However, there is some evidence to suggest interventions involving proactive policing to be more effective than traditional reactive policing. There was also an increased emphasis on developing policing interventions in collaborative partnerships, demonstrating the synergistic benefits in crime prevention through community partnerships, where communities were encouraged to take ownerships of their own problems and develop targeted responses to alcohol-related violence rather than a one-size-fits-all approach. Further research is required to define their effectiveness with the use of more appropriate and robust methodologies.

Orbitozygomatic Fracture Repairs: Are Antibiotics Necessary?

Orbitozygomatic fractures are one of the most common maxillofacial injuries encountered. This study aims to investigate and review the management and complications of orbitozygomatic fractures at the Royal Brisbane and Women's Hospital (RBWH). Specifically the postoperative infection rate will be closely examined to determine whether adjunctive antibiotics are necessary in its surgical management. A retrospective case selection study of all patients with orbitozygomatic fractures treated at the RBWH in 2011 was performed. The cases were collected from the maxillofacial database. Chart review of the admission with consecutive follow-up of up to 6 weeks including clinical and radiological assessment and consecutive data analysis was performed. A total of 160 patients with orbitozygomatic fractures were managed at the RBWH with three complications. Eighty-five (53.1%) cases were treated surgically and 155 (97.5%) cases had follow-up until 6 weeks postoperatively. Twenty-six surgical cases (16.3%) were treated via elevation without fixation. A further 26 surgical cases (16.3%) were treated with one fixation point, 19 cases (11.9%) with two fixation points, 12 cases (7.5%) with three fixation points, and 2 cases (1.3%) treated with four fixation points. The three complications (1.9%) returned for surgical correction without further consequence; two were due to inadequate cosmesis and one was due to exposure of the fixation plate. No early postoperative infections were seen. This study presents an excellent outcome with minimal early complications of orbitozygomatic fractures treated at the RBWH, a trauma center with high caseload. All operatively treated cases received perioperative antibiotic prophylaxis as per the unit's protocol. With a nil infection rate at the RBWH, future studies should focus on whether the use of prophylactic antibiotics is appropriate.

Bacterial comparison of preoperative rinsing and swabbing for oral surgery using 0.2% chlorhexidine.

AIM: The aim of the present study was to compare bacterial load using preoperative rinsing and swabbing techniques for oral surgery with 0.2% chlorhexidine (CHX). METHODS: Participants were healthy volunteers undergoing a general anesthetic for the removal of teeth. Participants were randomly allocated to receive 15 mL of 0.2% CHX for 60 s as either a rinse or have their mouths swabbed. Plaque samples were aseptically collected pre- and post-rinsing from the same sites in all patients (the distal surface of all second molar teeth). RESULTS: Patients in the swab group had similar bacteria counts before and after the application of CHX (143.4 vs 138.5 colonies, P = 1.000). After rinsing with CHX, there was an eightfold reduction of bacterial load (71 vs 8.8 colonies, P < 0.001). CONCLUSION: The present study demonstrates that the use of CHX as an antimicrobial agent is effective in reducing the overall number of bacterial colonies in the oral cavity. Rinsing is a more effective method of doing this.

Management of dental infections by medical practitioners.

BACKGROUND: Patients with dental infections frequently present to primary care practitioners such as emergency physicians or general practitioners. It is important for these healthcare professionals to understand how to assess and treat such conditions, including when to refer and to whom. OBJECTIVE: This article aims to cover basic principles of managing patients with dental infections who present to emergency departments or general practice surgeries. DISCUSSION: Maxillofacial surgeons frequently see serious cases of facial and neck infections that can easily be prevented if appropriately managed early.

A simplified approach for the reduction of specific closed anterior table frontal sinus fractures.

We describe a simplified approach to the management of closed anterior table fractures of the frontal sinus. Forty-seven patients were diagnosed with this type of fracture during a 3-year period. Of these, 6 had minimally-invasive periosteal raising of the anterior table through a small perieyebrow skin incision, and access to the fracture was through a small trephine or the edge of the fracture itself. We compared this with the more traditional approach of a coronal flap, which was associated with an increased duration of stay in hospital and the potential for neurological complications. Surgical intervention with a minimally-invasive trephine approach provides good cosmesis, minimal blood loss, intact neurological function, and rapid recovery. This makes it an important technique to consider in carefully selected patients.

Magnetic resonance imaging: an accurate, radiation-free, alternative to computed tomography for the primary imaging and three-dimensional reconstruction of the bony orbit.

PURPOSE: To determine the extent to which the accuracy of magnetic resonance imaging (MRI) based virtual 3-dimensional (3D) models of the intact orbit can approach that of the gold standard, computed tomography (CT) based models. The goal was to determine whether MRI is a viable alternative to CT scans in patients with isolated orbital fractures and penetrating eye injuries, pediatric patients, and patients requiring multiple scans in whom radiation exposure is ideally limited. MATERIALS AND METHODS: Patients who presented with unilateral orbital fractures to the Royal Brisbane and Women's Hospital from March 2011 to March 2012 were recruited to participate in this cross-sectional study. The primary predictor variable was the imaging technique (MRI vs CT). The outcome measurements were orbital volume (primary outcome) and geometric intraorbital surface deviations (secondary outcome) between the MRI- and CT-based 3D models. RESULTS: Eleven subjects (9 male) were enrolled. The patients' mean age was 30 years. On average, the MRI models underestimated the orbital volume of the CT models by 0.50 ± 0.19 cm(3). The average intraorbital surface deviation between the MRI and CT models was 0.34 ± 0.32 mm, with 78 ± 2.7% of the surface within a tolerance of ±0.5 mm. CONCLUSIONS: The volumetric differences of the MRI models are comparable to reported results from CT models. The intraorbital MRI surface deviations are smaller than the accepted tolerance for orbital surgical reconstructions. Therefore, the authors believe that MRI is an accurate radiation-free alternative to CT for the primary imaging and 3D reconstruction of the bony orbit.

Maxillofacial trauma.

BACKGROUND: Maxillofacial injuries are a common presentation to general practice and hospital emergency departments in Australia; surprisingly they can be easily overlooked at initial assessment. OBJECTIVE: This article describes the common typical clinical and radiographic findings in maxillofacial injuries that require further specialist treatment. Signs and symptoms requiring immediate treatment are highlighted and discussed individually. DISCUSSION: The full extent of functional disturbances might not be detectable in the first instance. Overlooked injuries may result in severe and enduring impairment of the patient and can have medicolegal ramifications.

Comminuted orbital blowout fracture after vigorous nose blowing that required repair.

A fracture of the orbital floor as a result of nose blowing is rare and we know of only three reported cases. We present a 40-year-old man who required repair of a blowout fracture of the orbital floor as a result of vigorous nose blowing. Patients who present with acute periorbital emphysema after nose blowing require careful assessment with potential blowout fractures in mind.

The patterns of facial injury suffered by patients in road traffic accidents: a case controlled study.

Road traffic accidents cause severe facial injuries and are frequently associated with injuries to other organ systems. The aims of this study were to define the facial injuries suffered by victims of road trauma and assess the need for a multidisciplinary approach to their management. A retrospective study of all patients over 14years of age suffering facial injuries over a five year period was conducted. Data was collected on the nature of their facial and other injuries and the impact of interspeciality management on their treatment. Four hundred and nine patients were identified. The midface was injured more frequently than the mandible and the majority of patients had multiple facial injuries. Neurologic, orthopaedic, thoracic and abdominal injuries were common and impacted on the management of the patients' facial trauma. Road traffic accidents cause more severe facial trauma than other mechanisms of injury. Other organ systems are more likely to be injured and the management of these injuries often impacts on their facial injury treatment demanding high levels of interspeciality cooperation.

Intraocular pressure changes secondary to reduction of orbito-zygomatic complex fractures.

PURPOSE: To investigate intraocular pressure (IOP) changes in the involved eye during orbito-zygomatic complex fracture reduction, compared with the IOP of the eye on the uninjured side. PATIENTS AND METHODS: Twenty patients who presented with displaced, isolated unilateral orbito-zygomatic complex fractures were enrolled. IOPs were measured using a Tono-Pen XL (Medtronic Solan, Jacksonville, FL) in the involved eye and in the non-involved eye. Pressure was recorded at 5 time points (before general anesthetic induction, after induction, immediately after fracture reduction, post operation while still under general anesthetic, and 15 minutes post general anesthetic). RESULTS: There were no significant differences between the injured and control data at any time point. Average IOPs for the involved and control eye decreased after anesthetic induction; however, IOP increased in both eyes after fracture reduction. CONCLUSION: There is no statistical evidence of a difference between the IOP of the control and injured eyes. Routine IOP testing is not indicated during orbito-zygomatic fracture reduction.

Emergency department management of maxillofacial trauma.

This paper highlights critical aspects of examination, diagnosis and early management of the maxillofacial trauma patient.

Management of isolated orbital floor blow-out fractures: a survey of Australian and New Zealand oral and maxillofacial surgeons.

BACKGROUND: This is the first report of involvement of Australian and New Zealand oral and maxillofacial surgeons in the management of isolated orbital floor blow-out fractures and was conducted to obtain comparisons with the results from a recent similar survey of British oral and maxillofacial surgeons. METHODS: A questionnaire survey was sent to all 113 practising members of the Australian and New Zealand Association of Oral and Maxillofacial Surgeons in April 2002 with a second mailout 1 month later. RESULTS: Sixty-nine per cent of the respondents were referred isolated orbital floor blow-out fractures for management, and just over half of these respondents estimated that 50% or more of the cases went to surgery. The materials most commonly used in orbital floor reconstruction were resorbable membrane for small defects and autologous bone for large defects. CONCLUSION: As in Britain, management of isolated orbital floor blow-out fractures comprises part of the surgical spectrum for many oral and maxillofacial surgeons in Australia and New Zealand. The management protocol was observed to be very similar between the two groups.