Evaluation of Mandibular Fractures in a German Nationwide Trauma Center Between 2015 and 2017.

Introduction: This study analyses the treatment of isolated mandibular fractures between 1.1.2015 and 21.31.2017 at Dortmund General Hospital. Materials and Methods: Patient documentation and radiological images have been assessed, and a descriptive statistical analysis has been performed. Results: Three hundred and twenty-eight patients were identified with isolated mandibular fractures (259 male, 69 female). The male-to-female ratio is 3.75: 1. A total of 541 fracture sites have been identified (1.65 fractures/patient). Forty of these were observed in the dentoalveolar region (fracture of the alveolar process, dental injuries), and the other 501 injuries were distributed in the remaining parts of the lower jaw.A detailed analysis of the osteosynthesis implants is provided. A total of 20 serious complications were observed (6% in all primary cases, 4.5% without osseointegrated implants). Discussion: The demographic data and the anatomical distribution of the fracture sites are comparable with international literature. Dentoalveolar injuries mostly occur in younger patients. The complication rate in this study (4.5%) is below the international data; however, we found a considerably higher rate than in the midfacial region (central midface: 0%, lateral midface: 1.43%). Despite this complication rate, the procedure can be considered safe. Supplementary information: The online version of this article (10.1007/s12663-021-01513-4).

Long-term evaluation of treatment protocols for isolated midfacial fractures in a German nation-wide craniomaxillofacial trauma center 2007-2017.

An update on the trends in maxillofacial traumatology provides additional information on the actual and changing needs. This retrospective study aimed to review all patient records of patients treated for isolated midface fractures in the Department of Cranial- and Maxillofacial Surgery at the Dortmund General Hospital between 2007 and 2017. The patient radiographs and patient files were reviewed. The safety and efficacy of the applied methods were controlled by assessing complications based on the Clavien-Dindo classification system. The statistical analysis included descriptive methods including regression analysis and χ2-test. In eleven years, 3474 isolated midface fracture sites have been identified in 2868 patients. The yearly trend is slightly increasing, in elderly clearly worsening, in children and youth decreasing. The male-to-female ratio was 2.16:1 for the whole study population, in the age group 18-25 y.o. 6.95:1 while in elderly above 80 y.o. 1:2.51, the age group specific incidence reflects this result, too. The most common fractures were nasal bone fractures (1405), zygomatic fractures (832) and orbital floor fractures (700). The average hospital stay was 2.7 days, the most fractures were operated within 24 h. The complication rate was 2.02% (Clavien-Dindo class II-V). The incidence of midfacial fractures is increasing in the total population and especially in elderly, but decreasing in children. Development of injury prevention measures is needed in this population. The diagnostic and therapeutic procedures are appropriate, as there is a low complication rate and short inpatient stay observed.

Evaluation of Panfacial Fractures in a German Supraregional Trauma Center between 2015 and 2017 - A Retrospective Study.

INTRODUCTION: Panfacial fractures represent the most severe injuries to the face. The combination of these fractures determines the treatment strategy. This study aims to retrospectively review the data of adult patients treated for complex facial skull fractures in a hospital in Dortmund, Germany from 2015-2017. MATERIALS AND METHODS: We extracted related patient data from the hospital electronic repository and reviewed the patient files and radiological images. The fractures were classified based on the AO-Classification. The statistical analysis was performed by descriptive statistical methods. The main goal was to determine the most common fracture combinations. RESULTS: A total of 188 patients with panfacial fractures were identified (181 adults, 7 children and adolescents). The gender and age distribution corresponded to the international literature (male-to-female ratio: 3.1:1, most common injuries among young men). 2-9 fracture sites were identified per patient, resulting in a fracture frequency of 3.13 per patient. 69 different fracture combinations have been identified. The most common ones were combinations of lateral and central mid-face fractures, and combinations of nasal bone fractures with lateral midface fractures or nasal bone fractures combined with mandibular fractures. Between 1 and 13 osteosynthesis implants per patient were used for osteosynthesis; the most commonly used plates were 2.0 mm and 1.5 mm straight plates. The average inpatient stay was 3 days (standard deviation [SD] = 3.0 days), and the average operation time (incision to suture) was 39.5 min (SD = 53.5 min). DISCUSSION: Panfacial fractures are the most complex maxillofacial injuries. The complication rate in this study (4.5%) is below the international data. The treatment of panfacial fractures requires designated centers with experienced teams and good interdisciplinary cooperation.

Fracture heat map of the facial skull demonstrates a danger zone of concomitant cervical spine injuries.

Concomitant maxillofacial and cervical spine injuries occur in 0.8-12% of the cases. We examined the relation of injury localization and the probability of cervical spine fracture. A retrospective study was conducted on patients that have been treated at Dortmund General Hospital for injuries both to the maxillofacial region and to the cervical spine between January 1st, 2007 and December 31th, 2017. Descriptive statistical methods were used to describe the correlation of cervical spine injuries with gender, age as well as maxillofacial injury localization. 7708 patients were hospitalized with maxillofacial injury, among them 173 were identified with cervical spine injury. The average ages for both genders lie remarkably above the average of all maxillofacial trauma patients (36.2 y.o. in male and 50.9 y.o. in female). In the group of men, most injuries were found between the ages of 50 and 65. Whereas most injuries among women occurred after the age of 80. The relative ratio of cervical spine injuries (CSI) varies between 1.1 and 5.26% of the maxillofacial injuries (MFI), being highest in the soft tissue injury group, patients with forehead fractures (3.12%) and patients with panfacial fractures (2.52%). Further, nasal, Le Fort I and II, zygomatic complex and mandibular condyle fractures are often associated with CSI. Fractures next to the Frankfurt horizontal plane represent 87.7% of all MFI with concomitant CSI. Patients in critical age groups with a high-energy injury are more likely to suffer both, MFI and CSI injuries. Our findings help to avoid missing the diagnosis of cervical spine injury in maxillofacial trauma patients.

A randomized, prospective trial to assess the safety and efficacy of hilotherapy in patients after orthognathic surgery.

PURPOSE: A post-operative cooling method in oral and maxillofacial surgery is the cooling with hilotherapy. The aim of this study was the post-operative comparison of cooling temperatures of 18°C and 22°C. The parameters of this trial were swelling and the post-operative pain levels. METHODS: This study included 156 patients, divided into two groups among whom a mono-one, bignathic osteotomy or genioplasty was indicated. The post-operative assessment of swelling was performed using a 3D optical scanner. This examination was repeated on post-operative days 1, 2, 3, 7, 14, 30, and 90. The examination on day 90 served as a reference value in respect of swelling and pain. RESULTS: Group 1 (18°C, 78 patients) showed an increase in post-operative swelling on the 1st post-OP day of 52.06 ± 35.41ml. The maximum was reached on the 2nd post-OP day with 75.82 ± 38.97ml. On the 30th post-OP day, residual swelling measured 11.60 ± 12.62ml. Group 2 (22 °C, 78 patients) showed an increase in postoperative swelling on the 1st post-OP day of 76.07 ± 63.15ml. The maximum was reached on the 2nd post-OP day with 106.97 ± 69.63 ml. On the 30th post-OP day, residual swelling measured 14.36 ± 32.26ml. The differences between the two groups and between different visits were statistically significant. CONCLUSION: The study results indicate less residual swelling in group 1 on the 30th post-OP day, possible based on the lower cooling temperature. The post-operative pain exhibits a comparable level of pain intensity between the two groups. In overall terms, a subjectively more agreeable treatment was observed in group 1.

Complications after osteosynthesis of craniofacial fractures-an analysis from the years 2015-2017.

BACKGROUND: Complications mean a recurring problem in everyday clinical practice. Complication rates between 6 and 13% are described for the treatment of bony injuries to the head and neck area. This paper aims to provide a detailed analysis of the complications after osteosynthesis in facial skull fractures. MATERIAL AND METHOD: In this retrospective study, we reviewed all patient records of injured treated in the Department of Cranial and Maxillofacial Surgery at the Dortmund General Hospital between 2015 and 2017. RESULTS: Of the 22,031 head and neck injuries, 685 were treated with osteosynthesis. A clinically significant complication was reported in 32 patients (4.76%). The number of total complications was 63. In total, 66.7% of all complications have been identified in the paramedian mandible (44%), median mandible, mandibular angle, and in the collar area (each 12.7%). Eleven implants (in 5 patients) showed a cancellous bone impaction. Broken implants have been recognized in two cases. In 8 cases, there was a pseudarthrosis in the fracture area; in one case, there was a broken implant and pseudarthrosis in combination. CONCLUSION: Osteosynthesis is a safe method of treating facial skull fractures, which is why we consider it the gold standard of therapy. The complication rate is well below 5%. The 3-dimensional adaptation (bending) and shortening of the osteosynthesis implants do not lead to an increase in complications.

Application of patient-specific simulation workflow for obstructive sleep apnea diagnosis and treatment with a mandibular advancement device.

A computational fluid dynamics simulation workflow was developed to analyze the upper airway of patients with obstructive sleep apnea, which is a potentially serious sleep-related breathing disorder. A single characteristic parameter was introduced to assess the severity of sleep apnea on the basis of the numerical results. Additionally, a fluid-structure interaction simulation was applied to study in detail the behavior of compliant pharyngeal walls. An experimental setup was designed to validate the patient-specific upper airway modeling. The suitability of the characteristic parameter was demonstrated in a retrospective analysis of radiological and clinical data of 58 patients as well as a prospective analysis of 22 patients. The simulation workflow was successfully used as part of an ongoing clinical investigation to predict the outcome of the obstructive sleep apnea treatment with a mandibular advancement device. The simulation results provided essential information about the critical region in the pharynx for the selection of an appropriate treatment and readily demonstrated the effect of mandibular protrusion on the air flow in the upper airway.

Hidden danger in the neck-a problem of differential diagnostics: benign chronic lymphadenitis following carotid endarterectomy and patch angioplasty (CEAP) or a metastasis due to a squamous cell cancer of the tongue.

INTRODUCTION: Oncological head and neck operations as well as carotid endarterectomy are common surgical procedures. In some occasions, both procedures have occurred in the past, leading to possible diagnostic and therapeutic challenges when follow-up operations seem indicated. CASE REPORT: We report of a patient presenting with carotid endarterectomy including patch operation 8 years ago and neck dissection due to a squamous cell cancer of the tongue 3 months ago, now showing up with a suspected metastatic tumor of the neck during routine follow-up. Intraoperatively, nearly fatal bleeding occurs due to a partial release of the carotid patch and needs to be managed immediately. DISCUSSION: The primarily pre-operated neck remains challenging for the radiologist in terms of differentiating between chronic lymphadenitis and metastasis. Furthermore, it remains challenging for the oncological surgeon in case these entities are in the near proximity of the previously operated carotid artery. The operative treatment according to the guidelines can lead to major bleeding during the second surgery. During the diagnostic process, metastases and chronic lymphadenitis after alloplastic carotid operations must be differentiated remaining however difficult, due to only scarce data in the literature. CONCLUSION: In the case of previous neck surgery, the decision to operate must be chosen individually regarding the specific conditions and their sometimes vital risks. In case an operation is indicated, the team must be trained to treat life-threatening intraoperative bleeding. In reviewing the literature, we were unable to find published recommendations on how to tackle these challenges.

Development of swelling following orthognathic surgery at various cooling temperatures by means of hilotherapy-a clinical, prospective, monocentric, single-blinded, randomised study.

PURPOSE: An alternative cooling method in oral and maxillofacial surgery is post-operative cooling with hilotherapy. It has not yet been clarified how the development of pain and swelling progresses post-operatively at different cooling temperatures. The aim of this study was the post-operative comparison of cooling temperatures of 18 °C and 22 °C. The parameters of this trial were swelling and the post-operative development of pain levels. In addition, the need for analgesics and patient satisfaction were documented. MATERIALS AND METHODS: This study included 36 patients, divided into two groups among whom a mono-one or bignathic osteotomy or genioplasty in orthognathic surgery was indicated. After the intervention, hilotherapy was employed directly instead of the conventional cooling method with moist compresses. The post-operative check of swelling during and after hilotherapy was performed using a 3D optical scanner (FaceSCAN3D®). This examination was repeated on post-operative days 1, 2, 3, 7, 14, 30 and 90. In this process, the final examination on day 90 served as a reference value in respect of swelling and pain. RESULTS: Group 1 (18 °C, 18 patients) showed an increase in post-operative swelling on the 1st post-operative day of 62.22 ± 36.29 ml. The maximum was reached on the 3rd post-operative day with 81.85 ± 40.23 ml. On the 30th post-operative day, residual swelling measured 7.39 ± 15.77 ml (p = 0.016). Group 2 (22 °C, 18 patients) showed an increase in postoperative swelling on the 1st post-operative day of 61.69 ± 34.7 ml. The maximum was reached on the 2nd post-operative day with 92.83 ± 48.03 ml. On the 30th post-operative day, residual swelling measured 28.09 ± 19.04 ml (p = 0.016). DISCUSSION: The study results indicate slightly less residual swelling in group 1 (18 °C) on the 30th post-operative day. One possible reason for this, based on the design of the study, could be the lower cooling temperature. The post-operative pain development exhibits a comparable level of pain intensity between the two groups. In overall terms, a subjectively more agreeable treatment was observed in group 1 (18 °C).

Moving the mandible in orthognathic surgery - A multicenter analysis.

Orthognathic surgery has always been a classical focus of maxillofacial surgery. Since more than 100 years, various surgical techniques for mandibular repositioning have been developed and clinically tested. Since the establishment of plate and screw osteosynthesis, orthognathic surgery became more stable and safe. Nowadays, different surgical methods for mobilising the mandible are existing. This international multicenter analysis (n = 51 hospitals) is providing first evidence based data for the current use of different surgical methods. The dominating techniques were Obwegeser/dal Pont (61%) followed by Hunsuck/Epker (37%) and Perthes/Schlössmann (29%). The main osteosynthesis materials were plates (82%), bicortical screws (23.5%), or a combination of both (5.9%). 47% of all centers reported to use several surgical methods at the same time, depending on the anatomical problem and the surgeon's preference. This shows that different surgical methods seem to work as comparable, safe, and reliable procedures in everydays clinical practise. On this basis, further prospective studies could evaluate possible advantages for our patients.

X-ray physics- and bone composition-based estimation of thickness characteristics from clinical mandibular radiographs.

In dentistry, clinical radiographs (also called X-ray images) reflect the intensity loss of an X-ray when being transmitted through the mandibular objects, and this loss is quantified in terms of grey values. While such images are standardly used for pathology detection by the experienced dentist, we here present a new method for getting more quantitative information out of such 2D radiographs, "extending" them into the third dimension. This "extension" requires consistent combination of X-ray physics (namely, X-ray intensity loss quantification along paths orthogonal to the panoramic clinical image and X-ray attenuation averaging for composite materials) with anatomically known upper and lower limits of vascular porosities in cortical and trabecular bone compartments. Correspondingly computed ranges of overall organ thicknesses are extremely narrow, suggesting adequate estimation of thickness characteristics from 2D radiographic panoramas used clinically, while predicted cortical and trabecular thickness ranges vary by ±8.47% and ±16.13%, respectively. The proposed method also identifies variations between thicknesses at similar anatomical locations left and right of the face's symmetry axis, and molar regions turn out to be thicker than those close to incisors. This paves the way to more detailed diagnostic activities, e.g. in combination with Finite Element simulations.

Multiaxial mechanical properties and constitutive modeling of human adipose tissue: a basis for preoperative simulations in plastic and reconstructive surgery.

A preoperative simulation of soft tissue deformations during plastic and reconstructive surgery is desirable to support the surgeon's planning and to improve surgical outcomes. The current development of constitutive adipose tissue models, for the implementation in multilayer computational frameworks for the simulation of human soft tissue deformations, has proved difficult because knowledge of the required mechanical parameters of fat tissue is limited. Therefore, for the first time, human abdominal adipose tissues were mechanically investigated by biaxial tensile and triaxial shear tests. The results of this study suggest that human abdominal adipose tissues under quasi-static and dynamic multiaxial loadings can be characterized as a nonlinear, anisotropic and viscoelastic soft biological material. The nonlinear and anisotropic features are consequences of the material's collagenous microstructure. The aligned collagenous septa observed in histological investigations causes the anisotropy of the tissue. A hyperelastic model used in this study was appropriate to represent the quasi-static multiaxial mechanical behavior of fat tissue. The constitutive parameters are intended to serve as a basis for soft tissue simulations using the finite element method, which is an apparent method for obtaining promising results in the field of plastic and reconstructive surgery.

Application of a new viscoelastic finite element method model and analysis of miniscrew-supported hybrid hyrax treatment.

INTRODUCTION: In this study, we aimed to assess the ability of a new viscoelastic finite element method model to accurately simulate rapid palatal expansion with a miniscrew-supported hybrid hyrax appliance. METHODS: A female patient received 3-dimensional craniofacial imaging with computed tomography at 2 times: before expansion and immediately after expansion, with the latter serving as a reference model for the analysis. A novel approach was applied to the finite element method model to improve simulation of the viscoelastic properties of osseous tissue. RESULTS: The resulting finite element method model was a suitable approximation of the clinical situation and adequately simulated the forced expansion of the midpalatal suture. Specifically, it demonstrated that the hybrid hyrax appliance delivered a force via the 2 mini-implants at the center of resistance of the nasomaxillary complex. CONCLUSIONS: The newly developed model provided a suitable simulation of the clinical effects of the hybrid hyrax appliance, which proved to be a suitable device for rapid palatal expansion.