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Ablative surgery of the orbit is often associated with dramatic changes in facial geometry. Surgical intervention is often necessary to correct the functional and esthetic appearance in those patients who are anophthalmic, having an intact eyelid appearance and an orbital prosthesis. The outcome of the surgical correction depends on the shape of the orbital implants and their adequate placement. In the case of comparatively small rearrangements, the effect of implants on soft tissues can be estimated by surgeons on the basis of their experience. However, large deformities in complex cases (including large deformation of soft tissue or asymmetry) can be hardly predicted on the basis of simple empirical considerations. The purpose of the present technical note was to describe a new procedure of inverse design of customized orbital titanium meshes. To demonstrate this procedure, an anophthalmic patient with superior sulcus deformity and enophthalmos was enrolled. The volume and structure of the extraocular muscles, soft tissue, and bony structure of the orbital walls were examined using high-resolution multislice computed tomography. Next, a geometric model of the patient's anatomy was generated from the tomography data. Afterward, the orbital prosthesis was virtually relocated to a new position. Then, the desired correction of the particular soft tissue regions was performed using virtual sculpturing tools. Next, the deformation of the soft tissues and initial prosthesis boundaries were computed from the predefined displacements of the relocated tissue regions with the help of the Finite Element Method. The differential volume between the initial and designated position of the orbital prosthesis yielded the preferred implant shape required to effect the desired correction of soft tissue. During surgery, the preplanned position of the customized titanium meshes was guided using a navigation system. Although the inverse design of custom-tailored titanium meshes for precision treatment of severe enophthalmos in anophthalmic patients appears to be a promising approach, it has rarely been applied in the past because of the technological complexity and additional time required. With the present study, we have launched a series of clinical evaluations of this novel method. To date, scientific evidence and trials showing a predictable simulation using an inverse finite element approach in the correction of severe enophthalmos in anophthalmic patients with computer-assisted fabricated individual titanium meshes for reconstruction of orbital walls have been rare. [ABSTRACT FROM AUTHOR]

Introduction: Dysphagia is a frequent problem in various neurological disorders. However, knowledge on swallowing function in patients with cerebral hypoxia is sparse. The objective of this study is to report the development of swallowing function in a series of adolescent and young-adult patients with cerebral hypoxia., Methods: We recruited eight patients (1 male) who were admitted to our institution after the acute phase following cerebral hypoxia. Each patient underwent detailed neurological evaluation, magnetic resonance imaging (MRI), standardized neurophysiological assessment and repeated clinical and fiber-endoscopic evaluation of swallowing. Furthermore, all patients received daily physical and occupational therapy and intensive logopedic therapy for swallowing., Results: Mean age in this case series was 19.9±3.6 years (range 16-25). All eight patients initially displayed severe swallowing dysfunction, but the reflexive components of swallowing were intact in seven patients without brainstem lesions. The only patient with additional brainstem involvement initially suffered from absence of an intact swallowing reflex and developed silent aspiration. However, follow-up examinations revealed intact swallowing reflexes in all eight patients., Discussion: Dysphagia is common in patients with cerebral hypoxia, mainly resulting in a delayed oral phase consistent with impaired volitional execution of swallowing. Additional lesions in the brainstem may affect the integrity of the central pattern-generating circuitry for swallowing, resulting in additional dysfunction of the non-volitional reflexive component. In conclusion, dysphagia in patients with cerebral hypoxia is a common complication particularly in the early stages of remission, while long-term prognosis with respect to swallowing is often good. Swallowing function should be closely monitored in patients with acquired brain injury.

Objectives: Clinical success of oral implants is related to primary stability and osseointegration. These parameters are associated with delicate surgical techniques. We herein studied whether template-guided drilling has a significant influence on drillholes diameter and accuracy in an in vitro model., Materials and Methods: Fresh cadaveric porcine mandibles were used for drilling experiments of four experimental groups. Each group consisted of three operators, comparing guide templates for drilling with free-handed procedure. Operators without surgical knowledge were grouped together, contrasting highly experienced oral surgeons in other groups. A total of 180 drilling actions were performed, and diameters were recorded at multiple depth levels, with a precision measuring instrument., Results: Template-guided drilling procedure improved accuracy on a very significant level in comparison with free-handed drilling operation (p ≤ 0.001). Inaccuracy of free-handed drilling became more significant in relation to measurement depth. High homogenic uniformity of template-guided drillholes was significantly stronger than unguided drilling operations by highly experienced oral surgeons (p ≤ 0.001)., Conclusion: Template-guided drilling procedure leads to significantly enhanced accuracy. Significant results compared to free-handed drilling actions were achieved, irrespective of the clinical experience level of the operator., Clinical Relevance: Template-guided drilling procedures lead to a more predictable clinical diameter. It shows that any set of instruments has to be carefully chosen to match the specific implant system. The current in vitro study is implicating an improvement of implant bed preparation but needs to be confirmed in clinical studies.

Purpose: The placement of self-tapping implants is associated with microfractures and the formation of bone chips along the cutting flutes. This study was conducted to investigate the effect of different cutting edge angles on chip formation during the machining of trabecular and cortical bone using instruments with a rough titanium surface., Materials and Methods: Mandibular cortical and trabecular bone specimens were obtained from freshly slaughtered domestic pigs. A predefined thrust force was applied to the specimens. Four specially designed cutting instruments that simulated dental implants and had a rough titanium surface were allowed to complete one full revolution at cutting edge angles of 55, 65, 75, and 85 degrees, respectively. Torque and thrust were measured during the cutting process. Bone chips were measured and weighed under a microscope., Results: Different cutting edge angles did not lead to significant differences in torque. The lowest torque values were measured when the cutting edges were positioned at 65 degrees in trabecular bone and at 85 degrees in cortical bone. Bone chips were significantly larger and heavier at angles of 55 and 65 degrees than at angles of 75 and 85 degrees in trabecular bone., Conclusion: Instruments with a rough titanium surface show considerable angle-dependent differences in chip formation. In addition to bone density, the angle of the cutting edges should be taken into consideration during the placement of dental implants. Good results were obtained when the cutting edges were positioned at an angle of 65 degrees. This angle can have positive effects on osseointegration.

Background: As a prerequisite in navigation-assisted surgery, a three-dimensional image data set with registration marker is necessary. Often patients are presented, not being aware of facing a computer-assisted surgical intervention (CAS), with an already performed computed tomography (CT) data set without marker. The aim of this study was to evaluate the accuracy of a new method which allows performing CAS by enhancing the initial markerless data set with a marked subvolume gained by cone beam (CBCT) scan., Methods: Therefore four registration markers are inserted and afterwards the patient is strongly limited to the field of interest scanned by CBCT scan (marked data set). Superimposed with the initial data set, a data set with reference markers and with full information is obtained. Registration procedure was performed with group A (25 patients, superimposed marked CBCT scan) and group B (25 patients, initially marked CT scan) using BrainLab® navigation by two observers and overall system accuracy was measured using the registration landmarks and additional intraoperative landmarks (tooth cusps)., Results: Adequate image quality assumed, no significant difference between group A and B was detected. Enhancing an initially performed data set with registration marker by using a marked subvolume could improve the workflow for navigation-assisted surgery due to the availability of cone beam scan technology, provide excellent resolution with reduced metal artifacts nearby dental restorations, and reduce radiation dose for the patient., Conclusion: Regarding the advantages of the new method which allows performing CAS by enhancing the initial markerless data set with a marked subvolume gained by cone beam (CBCT) scan, this technique will play a major part in navigation-assisted surgery and will address widespread general methodological solutions that are of great interest in multidisciplinary treatment., (Copyright © 2013 John Wiley & Sons, Ltd.)

Background: The aim of orbital wall reconstruction is to reestablish anatomically exact orbital volumes to avoid long-term complications. Navigation could facilitate complex reconstructions., Methods: Quality of the orbital reconstruction (n=94) was measured based on (A) volume changes and (B) on 3D shape deviations compared to the unaffected side. Volume analysis included segmentation of the orbital cavity in the pre- and post-operative 3D data set (VoXim®, IVS Solutions, Germany), and shape analysis was performed by vector-based 3D tools (Comparison®, 3Dshape, Germany)., Results: Orbital volume of the unaffected side ranged from 26.6 ml±2.8 ml in male and 25.2 ml±2.6 ml in female (CT). Significant orbital enlargement was found in orbital fractures with involvement of the posterior third of the orbital floor and in comminuted fracture pattern. Reconstructed orbital volume ranged from 26.9±2.7 ml in male and 24.26±2.5 ml in female (CBCT). 3D Analysis of the color mapping showed minor deviations compared to the mirrored unaffected side., Conclusion: Measurements demonstrate that even in comminuted orbital fractures true-to-original reconstruction is feasible.

Background: Although extracranial internal carotid artery (e-ICA) occlusion is a common pathology in patients undergoing intravenous thrombolysis for treatment of acute ischemic stroke, no data on e-ICA recanalization rate or potential effects on outcome are yet available., Methods and Results: This study included 52 consecutive patients with e-ICA occlusion and ischemic stroke undergoing standard intravenous thrombolysis. The rate of e-ICA recanalization was 30.8% [95%CI, 18.2-43.3], documented at 3.5 [2.0-11.8] (median [IQR]) days after stroke, as compared to 8.6% [95%CI, 3.5-13.7] in a series of 116 consecutive patients with symptomatic e-ICA occlusion not undergoing thrombolysis (P<0.001 for difference). Functional outcome three months after stroke did not significantly differ for those with or without e-ICA recanalization following intravenous thrombolysis (modified Rankin scale ≤2: 31.3% vs. 22.2%, odds ratio 1.6 [95%CI, 0.4-5.9], P = 0.506). In patients with e-ICA occlusion of atherothrombotic origin, recanalization resulted in most instances in residual high-grade stenosis (13 of 14)., Conclusions: Recanalization of e-ICA occlusion after stroke thrombolysis occurred in about one third of patients. Although e-ICA recanalization had no significant effect on patient outcome, control sonography in the early days after thrombolysis is recommended for the detection of potential residual e-ICA stenosis.

Objective: To quantify the risk for bleeding complications after thrombolysis for ischemic stroke in patients on warfarin (international normalized ratio [INR] ≤ 1.7) and to put these data into perspective with previous studies., Methods: A total of 548 consecutive stroke patients receiving IV recombinant tissue plasminogen activator (rtPA) were prospectively evaluated and details about warfarin pretreatment were carefully recorded. Prothrombin time-based INR values were measured before thrombolysis and 6 and 24 hours thereafter. Intracranial hemorrhage occurring within 72 hours was assessed by CT examinations and defined according to National Institute of Neurological Disorders and Stroke criteria. Main outcome variables were symptomatic intracranial and major systemic bleedings., Results: Of the 548 patients, 33 (6.0%) and 14 (2.6%) experienced symptomatic intracranial and major systemic bleedings, respectively. Patients taking warfarin until the day of or day before admission (n = 15, mean ± SD INR 1.21 ± 0.32 vs 1.01 ± 1.12, p = 0.030) faced an approximately 4-fold risk for intracranial hemorrhage (20.0% vs 5.6%, unadjusted odds ratio [OR] [95% confidence interval (CI)] 4.2 [1.1-15.7], p = 0.033). Findings were similar after adjustment for age, NIH Stroke Scale score, and diabetes (adjusted OR [95% CI] 4.1 [1.0-16.1], p = 0.044) and when focusing on any major bleeding (intracranial or systemic) (unadjusted OR [95% CI] 4.1 [1.3-13.6], p = 0.019). Half of the patients with bleedings showed an INR rise above 1.7 6 hours after thrombolysis. A meta-analysis yielded confirmatory yet heterogeneous results (unadjusted OR [95% CI] derived from a random effects model, 2.31 [1.15-4.62], p = 0.018, I(2) = 58% [11%-80%])., Conclusions: Our data suggest a statistically significant and clinically meaningful increase in the risk for symptomatic intracranial and major systemic bleedings among patients with stroke thrombolysis receiving warfarin up to the day of or day before stroke.

Background: Modern high-velocity projectiles produce temporary cavities and can thus cause extensive tissue destruction along the bullet path. It is still unclear whether gelatin blocks, which are used as a well-accepted tissue simulant, allow the effects of projectiles to be adequately investigated and how these effects are influenced by caliber size., Method: Barium titanate particles were distributed throughout a test chamber for an assessment of wound contamination. We fired .22-caliber Magnum bullets first into gelatin blocks and then into porcine hind limbs placed behind the chamber. Two other types of bullets (.222-caliber bullets and 6.5 × 57 mm cartridges) were then shot into porcine hind limbs. Permanent and temporary wound cavities as well as the spatial distribution of barium titanate particles in relation to the bullet path were evaluated radiologically., Results: A comparison of the gelatin blocks and hind limbs showed significant differences (p < 0.05) in the mean results for all parameters. There were significant differences between the bullets of different calibers in the depth to which barium titanate particles penetrated the porcine hind limbs. Almost no particles, however, were found at a penetration depth of 10 cm or more. By contrast, gas cavities were detected along the entire bullet path., Conclusion: Gelatin is only of limited value for evaluating the path of high-velocity projectiles and the contamination of wounds by exogenous particles. There is a direct relationship between the presence of gas cavities in the tissue along the bullet path and caliber size. These cavities, however, are only mildly contaminated by exogenous particles.

Changes in ambient pressure occur during flying, diving, or hyperbaric oxygen therapy and can cause different types of pathophysiological conditions and pain including toothache (barodontalgia). We report the case of a patient with severe pain in the region of his mandibular left first molar, which had been satisfactorily restored with a conservative restoration. Pain occurred during an airplane flight and persisted after landing. Radiology revealed a periapical radiolucency in the region of the distal root apex. Pain relief was achieved only after endodontic treatment. On the basis of this paper, we investigated the aetiology and management of barodontalgia. Dentists should advise patients to avoid exposure to pressure changes until all necessary surgical, conservative, and prosthetic procedures have been completed. The influence of pressure divergences should be noted at any time. Under changed environment pressures may be the changing perception of pathologies.

Over the past years, computer-assisted surgery has gained more importance in craniomaxillofacial surgery, especially in primary and secondary treatment of head and neck malignancies. The basis for oncologic treatment of the head and neck region requires detailed planning using computed tomography, cone-beam computed tomography, or magnetic resonance imaging in combination with computer-assisted, infrared-based navigation system. These techniques allow a preplanned image-guided path to the tumor region for taking biopsies, resection, or reconstruction. The aim of this work was to show the advances and technical benefits for tumor surgery in a daily clinical routine from the view of the craniomaxillofacial surgeon. The target of our working group was to develop and clinically evaluate a novel three-dimensional planning and navigation software solution for treatment of craniofacial tumors. This work was carried out on 5 categories for oncologic surgical procedures in which computer-assisted surgery was applied from 2005 to 2011: preplanned trajectorial-guided tumor biopsy, intraoperative image-controlled tumor resection, tumor mapping, reconstruction after tumor surgery (true to original), and oral rehabilitation (backward planning). Successful preoperative planning, import of image data suitable for navigation, and intraoperative precise infrared-based navigation were obtained for all 5 categories without any complications. Image-guided navigation technique for head and neck oncologic surgery provides a precise, safe surgical method with real-time excellent anatomic orientation. Regarding the advantages of computer-assisted surgery, this technique will play a major part in craniofacial reconstructive surgery and will address widespread general methodologic solutions that are of great interest in multidisciplinary oncologic treatment.

Aim. To measure and validate the permeability of pressure changes in correlation to different root filling techniques. Methods. Eighty extracted single-rooted teeth were randomly assigned to one of eight groups of ten teeth. Following standardized instrumentation and irrigation, root canal fillings were performed using either cold lateral condensation, a warm carrier-based gutta-percha obturation technique, a warm carrier-based Resilon, or warm gutta-percha compaction with the downpack/backfill technique. After insertion of a pressure sensor within the pulp chamber ten teeth of each group then underwent simulated dives with pressure measurement and the other ten a dye penetration test during simulated dives to 5.0 bar. Differences were analyzed statistically (P < 0.05) using one-way analysis of variance (ANOVA). Results. When the warm carrier-based gutta-percha obturation technique and vertical gutta-percha obturation techniques were used, there was significant lower intrapulpal pressure to experimental chamber pressure (P > 0.05). When cold lateral condensation or carrier-based Resilon as used, pressure was sometimes almost completely equalized. Conclusions. Warm gutta-percha obturation techniques provide a largely pressure-tight seal whereas the Resilon obturation technique and cold lateral condensation appear to be unsuitable to pressure changes.

The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists.

Objectives: Reconstruction of large mandiblular defects following ablative oncologic surgery could be done by using vascularized bone transfer or, more often, primarily with simultaneous or delayed bone grafting, using load bearing reconstruction plates. Bending of these reconstruction plates is typically directed along the outer contour of the original mandible. Simultaneously or in a second operation vascularized or non-vascularized bone is fixed to the reconstruction plate. However, the prosthodontic-driven backward planning to ease bony reconstruction of the mandible in terms of dental rehabilitation using implant-retained overdentures might be an eligible solution. The purpose of this work was to develop, establish and clinically evaluate a novel 3D planning procedure for mandibular reconstruction., Materials and Methods: Three patients with tumors involving the mandible, which included squamous cell carcinoma in the floor of the mouth and keratocystic odontogenic tumor, were treated surgically by hemimandibulectomy., Results: In primary alloplastic mandible reconstruction, shape and size of the reconstruction plate could be predefined and prebent prior to surgery., Clinical Relevance: This study provides modern treatment strategies for mandibular reconstruction.

Objectives: In this retrospective study, we present a clinical review of our experience with tongue cancer in order to obtain valid criteria for therapeutic decision-making., Materials and Methods: Between August 1999 and June 2011, a total of 398 patients with squamous cell carcinoma of the tongue were treated at the Department of Oral and Maxillofacial Surgery, King Edward Medical University Lahore Pakistan. Data concerning patient characteristics, clinical and pathologic tumour characteristics and treatment strategies and their results were obtained from a retrospective review of medical records. The average follow-up was 4.6 years. Statistical analysis for survival was calculated by the method of Kaplan and Meier., Results: There were 398 total patients. The mean age at diagnosis was 49.5 years,. 224 (56.3%) were male and 174 (43.7%) female (male/female ratio = 1.3:1).332/398 patients received surgical treatment, whereas 66 patients were excluded from surgical treatment and received primary radio (chemo) therapy after biopsy. Tongue carcinoma patients treated by non surgical treatment modalities had 5 years survival rate of 45.5% and patients with surgical intervention had survival rate of 96.1%., Conclusions: We recommend categorical bilateral neck dissection in order to reliably remove occult lymph node metastases. Adjuvant treatment modalities should be applied more frequently in controlled clinical trials and should generally be implemented in cases with unclear margins and lymphatic spread., Clinical Relevance: This study provides modern treatment strategies for the tongue carcinoma.

Purpose: The aim of the present retrospective study was to assess the suitability of segmental mandibular sandwich osteotomy combined with an interpositional autograft to meet the dimensional requirements of preimplant bone augmentation in cases of a severely atrophic mandible., Patients and Methods: A total of 27 consecutive patients (6 men and 21 women) were included in the present study. The amount of bone gain was calculated using digital volume tomography before surgery and 3 months after bone augmentation., Results: The postoperative course was uneventful for 18 patients. Temporary sensory disturbances were observed in 6 patients, with complete recovery after 3 to 12 weeks. Dehiscence of soft tissue closure occurred in 3 patients. The mean vertical gain was 3.41 mm (range 0.3 to 12). The mean horizontal gain was 3.08 mm (range 0.2 to 8.5). A total of 88 implants were placed in 40 surgical sites at 12 weeks after bone reconstruction., Conclusion: Segmental mandibular sandwich osteotomy is a suitable augmentation procedure in the mandible for the atrophic alveolar ridge and provides adequate height and transversal bone augmentation., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: In this retrospective study, we present a clinical review of our experience with tongue cancer in order to obtain valid criteria for therapeutic decision-making., Materials and Methods: Between 1980 and 2009, a total of 341 patients with squamous cell carcinoma of the tongue were treated at our Department. The average follow-up was 5.2 years. 309 patients received surgical treatment, which was combined in nearly 10% with neoadjuvant and in nearly 20% with postoperative radio(chemo)therapy. 32 patients were excluded from surgery and received primary radiation., Results: Local and regional failure occurred in 23.9% and 20.4%, leading to a total failure rate of 37.2% after an average duration of 1,6 years. N-Status, extracapsular spread and clear margins were identified as the dominant factors for survival, which was calculated with 54.5% after 5 years., Conclusions: We recommend categorical bilateral neck dissection in order to reliably remove occult lymph node metastases. Adjuvant treatment modalities should be applied more frequently in controlled clinical trials and should generally be implemented in cases with unclear margins and lymphatic spread., Clinical Relevance: This study provides new treatment strategies for primary tumour disease and for tumour recurrence.

The alteration of rheological blood properties as well as deterioration of vascular perfusion conditions and cell-cell interactions are major determinants of thrombus formation. Herein, we present an experimental model which allows for quantitative in vivo microscopic analysis of these determinants during both thrombus formation and vascular recanalisation. The model does not require surgical preparation procedures, and enables for repeated analysis of identical microvessels over time periods of days or months, respectively. After i.v. administration of FITC-dextran thrombus formation was induced photochemically by light exposure to individual arterioles and venules of the ear of ten anaesthetised hairless mice. In venules, epi-illumination induced rapid thrombus formation with first platelet deposition after 0.59 +/- 0.04 min and complete vessel occlusion within 7.48 +/- 1.31 min. After a 24-h time period, 75% of the thrombosed venules were found recanalised. Marked leukocyte-endothelial cell interaction in those venules indicated persistent endothelial cell activation and/or injury, even after an observation period of 7 days. In arterioles, epi-illumination provoked vasomotion, while thrombus formation was significantly (p <0.05) delayed with first platelet deposition after 2.32 +/- 0.22 min and complete vessel occlusion within 20.07 +/- 3.84 min. Strikingly, only one of the investigated arterioles was found recanalised after 24 h, which, however, did not show leukocyte-endothelial cell interaction. Heparin (300 U/kg, i.v.) effectively counteracted the process of thrombus formation in this model, including both first platelet deposition and vessel occlusion. We conclude that the model of the ear of the hairless mouse allows for distinct in vivo analysis of arteriolar and venular thrombus formation/recanalisation, and, thus, represents an interesting tool for the study of novel antithrombotic and thrombolytic strategies, respectively.