Real-world evidence from over one million COVID-19 vaccinations is consistent with reactivation of the varicella-zoster virus.

BACKGROUND: Reactivation of the varicella-zoster virus (VZV), which causes herpes zoster (HZ, synonym: shingles) in humans, can be a rare adverse reaction to vaccines. Recently, reports of cases after COVID-19 vaccination have arisen. OBJECTIVES: The aim of this study was to assess whether the frequency of HZ is found to increase after COVID-19 vaccination in a large cohort, based on real-world data. As a hypothesis, the incidence of HZ was assumed to be significantly higher in subjects who received a COVID-19 vaccine (Cohort I) vs. unvaccinated individuals (Cohort II). METHODS: The initial cohorts of 1 095 086 vaccinated and 16 966 018 unvaccinated patients were retrieved from the TriNetX database and were matched on age and gender in order to mitigate confounder bias. RESULTS: After matching, each cohort accounted for 1 095 086 patients. For the vaccinated group (Cohort I), 2204 subjects developed HZ within 60 days of COVID-19 vaccination, while among Cohort II, 1223 patients were diagnosed with HZ within 60 days after having visited the clinic for any other reason (i.e. not vaccination). The risk of developing shingles was calculated as 0.20% and 0.11% for cohort I and cohort II, respectively. The difference was statistically highly significant (P < 0.0001; log-rank test). The risk ratio and odds ratio were 1.802 (95% confidence interval [CI] = 1.680; 1.932) and 1.804 (95% CI = 1.682; 1.934). CONCLUSIONS: Consistent with the hypothesis, a higher incidence of HZ was statistically detectable post-COVID-19 vaccine. Accordingly, the eruption of HZ may be a rare adverse drug reaction to COVID-19 vaccines. Even though the molecular basis of VZV reactivation remains murky, temporary compromising of VZV-specific T-cell-mediated immunity may play a mechanistic role in post-vaccination pathogenesis of HZ. Note that VZV reactivation is a well-established phenomenon both with infections and with other vaccines (i.e. this adverse event is not COVID-19-specific).

Performance of cone-beam computed tomography and multidetector computed tomography in diagnostic imaging of the midface: A comparative study on Phantom and cadaver head scans.

PURPOSE: To compare multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) regarding radiation, resolution, image noise, and image quality. METHODS: CBCT and 256-MDCT were compared based on three scan protocols: Standard-dose (≈24 mGy), reduced-dose (≈9 mGy), and low-dose (≈4 mGy). MDCT images were acquired in standard- and high-resolution mode (HR-MDCT) and reconstructed using filtered back projection (FBP) and iterative reconstruction (IR). Spatial resolution in linepairs (lp) and objective image noise (OIN) were assessed using dedicated phantoms. Image quality was assessed in scans of 25 cadaver heads using a Likert scale. RESULTS: OIN was markedly higher in FBP-MDCT when compared to CBCT. IR lowered the OIN to comparable values in standard-mode MDCT only. CBCT provided a resolution of 13 lp/cm at standard-dose and 11 lp/cm at reduced-dose vs. 11 lp/cm and 10 lp/cm in HR-MDCT. Resolution of 10 lp/cm was observed for both devices using low-dose settings. Quality scores of MDCT and CBCT did not differ at standard-dose (CBCT, 3.4; MDCT, 3.3-3.5; p > 0.05). Using reduced- and low-dose protocols, CBCT was superior (reduced-dose, 3.2 vs. 2.8; low dose, 3.0 vs. 2.3; p < 0.001). CONCLUSION: Using the low-dose protocol, the assessed CBCT provided better objective and subjective image quality and equality in resolution. Similar image quality, but better resolution using CBCT was observed at higher exposure settings. KEY POINTS: • The assessed CBCT device provided better image quality at lower doses. • Objective and subjective image quality were comparable using higher exposure settings. • CBCT showed superior spatial resolution in standard-dose and reduced-dose settings. • Modern noise-reducing tools are used in CBCT devices currently. • MDCT should be preferred for assessment of soft-tissue injuries and oncologic imaging.

Clinical and social success in epithetic ear rehabilitation - Retrospectively evaluating the long-term survival of auricular implants.

PURPOSE: The aim of this study was to evaluate existing staging recommendations for peri-implantitis and its applicability for auricular bone anchoring. MATERIALS AND METHODS: In this cross-sectional study, 44 patients treated with 47 ear epitheses and 128 implants were analyzed over 191.6 months (mean). Peri-implant sulcus depth, sulcus fluid flow rate, and peri-implant skin reaction, as well as cleaning habits and patients' quality of life, were analyzed. Mixed effect linear and mixed effect ordered logistic regression models were used. RESULTS: Two of the 128 implants were lost (1.6 %). A total of 14.5 % of all patients presented light erythemas, 19.4 % showed stage 2, 4.8 % stage 3, and 12.9 % an acute infection according to Holgers. A correlation between skin reaction and sulcus fluid flow rate was observed, when grouping patients with acute signs of inflammation. Concerning patient satisfaction, 58.1 % of the patients were highly satisfied with their epitheses, 39.5 % very satisfied, and one patient was just satisfied. Younger age correlated with lower satisfaction rates. CONCLUSION: Implant-retained auricular epitheses are a safe, highly sufficient and satisfying way of extending ear reconstruction. Sulcus depth and skin reaction are quick and valuable assessment tools in auricular implants, but skin reaction alone was clinically insufficient to predict peri-implant pocket inflammation.

Design and evaluation of a deep learning-based automatic segmentation of maxillary and mandibular substructures using a 3D U-Net.

Background: Current segmentation approaches for radiation treatment planning in head and neck cancer patients (HNCP) typically consider the entire mandible as an organ at risk, whereas segmentation of the maxilla remains uncommon. Accurate risk assessment for osteoradionecrosis (ORN) or implant-based dental rehabilitation after radiation therapy may require a nuanced analysis of dose distribution in specific mandibular and maxillary segments. Manual segmentation is time-consuming and inconsistent, and there is no definition of jaw subsections. Materials and methods: The mandible and maxilla were divided into 12 substructures. The model was developed from 82 computed tomography (CT) scans of HNCP and adopts an encoder-decoder three-dimensional (3D) U-Net structure. The efficiency and accuracy of the automated method were compared against manual segmentation on an additional set of 20 independent CT scans. The evaluation metrics used were the Dice similarity coefficient (DSC), 95% Hausdorff distance (HD95), and surface DSC (sDSC). Results: Automated segmentations were performed in a median of 86 s, compared to manual segmentations, which took a median of 53.5 min. The median DSC per substructure ranged from 0.81 to 0.91, and the median HD95 ranged from 1.61 to 4.22. The number of artifacts did not affect these scores. The maxillary substructures showed lower metrics than the mandibular substructures. Conclusions: The jaw substructure segmentation demonstrated high accuracy, time efficiency, and promising results in CT scans with and without metal artifacts. This novel model could provide further investigation into dose relationships with ORN or dental implant failure in normal tissue complication prediction models.

Development and validation of the Burdens in Oral Surgery Questionnaire (BiOS-Q).

Patients' perspective is increasingly re-cognised as an important outcome measure in oral surgery. However, how patients perceive the surgical treatment cannot be assessed currently. This would be an important indicator for process-related quality of care. It was the aim to develop and to validate an instrument for the assessment of patient-based measures of process-related quality of care in oral surgery. The new Burdens in Oral Surgery Questionnaire (BiOS-Q) was developed in two steps in patients undergoing oral surgery. First, an item pool was created using semi-structured interviews in 90 patients. Second, a preliminary version was applied in 297 consecutively recruited patients to assess redundancy, completion rates, face validity, difficulty and distribution. Psychometric properties of the final version of the questionnaire were evaluated. The BiOS-Q consists of 16 items and showed satisfactory internal consistency (Cronbach's alpha = 0·84) and excellent test-retest reliability (ICC = 0·90). The questionnaire's mean score was significantly correlated with dentists' burdens (r = 0·44) and patients' overall satisfaction (r = 0·39) indicating sufficient validity. The BiOS-Q is a reliable and valid instrument for the assessment of patient-based process-related quality of care in oral surgery.

Imaging the Tight Orbit: Radiologic Manifestations of Orbital Compartment Syndrome.

BACKGROUND AND PURPOSE: Orbital compartment syndrome is a sight-threatening emergency caused by rising pressure inside the orbit. It is usually diagnosed clinically, but imaging might help when clinical findings are inconclusive. This study aimed to systematically evaluate imaging features of orbital compartment syndrome. MATERIALS AND METHODS: This retrospective study included patients from 2 trauma centers. Proptosis, optic nerve length, posterior globe angle, morphology of the extraocular muscles, fracture patterns, active bleeding, and superior ophthalmic vein caliber were assessed on pretreatment CT. Etiology, clinical findings, and visual outcome were obtained from patient records. RESULTS: Twenty-nine cases of orbital compartment syndrome were included; most were secondary to traumatic hematoma. Pathologies occurred in the extraconal space in all patients, whereas intraconal abnormalities occurred in 59% (17/29), and subperiosteal hematoma in 34% (10/29). We observed proptosis (affected orbit: mean, 24.4 [SD, 3.1] mm versus contralateral: 17.7 [SD, 3.1] mm; P < .01) as well as stretching of the optic nerve (mean, 32.0 [SD, 2.5] mm versus 25.8 [SD, 3.4] mm; P < .01). The posterior globe angle was decreased (mean, 128.7° [SD, 18.9°] versus 146.9° [SD, 6.4°]; P < .01). In 69% (20/29), the superior ophthalmic was vein smaller in the affected orbit. No significant differences were detected regarding the size and shape of extraocular muscles. CONCLUSIONS: Orbital compartment syndrome is characterized by proptosis and optic nerve stretching. In some cases, the posterior globe is deformed. Orbital compartment syndrome can be caused by an expanding pathology anywhere within the orbit with or without direct contact to the optic nerve, confirming the pathophysiologic concept of a compartment mechanism.

Removal of patient-specific reconstruction plates after mandible reconstruction with a fibula free flap: is the plate the problem?

Computer-aided microvascular mandible reconstruction is an increasingly common procedure in oral and maxillofacial surgery. The aim of this retrospective single-centre study was to evaluate the rate and specifics of hardware removal after fibula free flap (FFF) fixation with a patient-specific reconstruction plate. The study included patients who underwent hardware removal between April 2017 and October 2019. Statistical analyses were performed regarding the different indications for plate removal (dental implantation versus complication) and the surgical approach (intraoral versus extraoral). Plate removal was performed in 29 of 98 patients (29.6%) after FFF fixation with a patient-specific reconstruction plate. Plate removal was done prior to dental implantation in 58.6% of cases and due to complications in 41.4%. Complications seen between reconstructive surgery and plate removal were less frequent in the dental rehabilitation group (8/17 vs 12/12; P=0.002). Within this group, 35.3% of plates were removed intraorally, and the majority of partial plate removals were performed in the patients with plate removal for dental rehabilitation (72.7% vs 27.3%). Hospitalization was shorter with an intraoral approach (1.7 days vs 4.0 days, P=0.052). The removal of patient-specific reconstruction plates prior to dental implantation is often partial and can be performed intraorally. The use of patient-specific miniplates for fixation of FFF might facilitate later dental rehabilitation.

Biomechanical comparison of polylactide-based versus titanium miniplates in mandible reconstruction in vitro.

OBJECTIVES: Evaluation of the mechanical integrity and reliability of polylactide-based miniplates for osseous free flap fixation at the mandible in an experimental study setup of a mandible reconstruction model. MATERIAL AND METHODS: 1.0mm titanium miniplates (group TI) (MatrixMandible, DePuy Synthes, Umkirch, Germany) and 1.5mm polylactide miniplates (group PL) (Inion CPS, Inion Oy, Tampere, Finland) were used to fix a polyurethane (PU) fibula segment to a PU mandible reconstruction model using monocortical non-locking screws. Mastication was simulated via unilateral cyclic dynamic loading at 1Hz with increasing loads (+ 0.15N/cycle, Bionix, MTS, USA). A 3D optical tracking system (Aramis, GOM, Braunschweig, Germany) was used to determine interosteotomy movements (IOM). RESULTS: IOM were higher in the polylactide group (distal: P=0.001, mesial: P=0.001). Differences in mean stiffness (titanium: 478±68N/mm; polylactide: 425±38N/mm, P=0.240) and mean force at a vertical displacement of 1.0mm (titanium: 201.6±87.1N; polylactide: 141.3±29.9N, P=0.159) were not significant. CONCLUSIONS: The results of this study suggest that polylactide-based miniplates provide reduced mechanical integrity and higher interosteotomy movements in comparison to titanium miniplates in vitro. Indications for clinical use of polylactide-based miniplates in mandible reconstruction have to be placed critically. Future studies will focus on clinical complications of polylactide-based plates in risk patients.

Complication rates and clinical outcomes of osseous free flaps: a retrospective comparison of CAD/CAM versus conventional fixation in 128 patients.

Studies evaluating plate-related complications in patient-specific versus conventional fixation systems in free flap surgery are lacking. This was a retrospective study of 128 osseous free flaps with a minimum follow-up of 12 months. Wound healing disorders, plate exposure, fixation failure, and subtotal osseous union were recorded and evaluated statistically by univariate and regression analysis. Complication rates were as follows: wound healing disorders 33.6% (computer-aided design and computer-aided manufacturing (CAD/CAM) vs. conventional: 35.1% vs. 33.0%); plate exposure 21.9% (29.7% vs. 18.7%); fixation failure 7.0% (8.1% vs. 6.6%); subtotal osseous union 36.7% (45.9% vs. 33.0%). Radiotherapy (P<0.001) and more than two segments (P=0.026) were independent variables for the overall complication rate and were negatively correlated with the dental implantation rate. The time between diagnosis and ablative surgery was increased by 11.0days in the CAD/CAM group (34.2±16.2days vs. 23.2±12.0 days; P=0.002). Rates of dental rehabilitation were not significantly different (35.1% vs. 44.0%, P=0.358). On average, 3.2±1.7 dental implants were placed into flap segments. Plate-related complications were increased with radiotherapy and multisegment flaps. There was a non-significant trend towards increased complications with patient-specific plates in comparison to conventional reconstruction plates.

A Century of Change towards Prevention and Minimal Intervention in Cariology.

Better understanding of dental caries and other oral conditions has guided new strategies to prevent disease and manage its consequences at individual and public health levels. This article discusses advances in prevention and minimal intervention dentistry over the last century by focusing on some milestones within scientific, clinical, and public health arenas, mainly in cariology but also beyond, highlighting current understanding and evidence with future prospects. Dentistry was initially established as a surgical specialty. Dental caries (similar to periodontitis) was considered to be an infectious disease 100 years ago. Its ubiquitous presence and rampant nature-coupled with limited diagnostic tools and therapeutic treatment options-meant that these dental diseases were managed mainly by excising affected tissue. The understanding of the diseases and a change in their prevalence, extent, and severity, with evolutions in operative techniques, technologies, and materials, have enabled a shift from surgical to preventive and minimal intervention dentistry approaches. Future challenges to embrace include continuing the dental profession's move toward a more patient-centered, evidence-based, less invasive management of these diseases, focused on promoting and maintaining oral health in partnership with patients. In parallel, public health needs to continue to, for example, tackle social inequalities in dental health, develop better preventive and management options for existing disease risk groups (e.g., the growing aging population), and the development of reimbursement and health outcome models that facilitate implementation of these evolving strategies. A century ago, almost every treatment involved injections, a drill or scalpel, or a pair of forceps. Today, dentists have more options than ever before available to them. These are supported by evidence, have a minimal intervention focus, and result in better outcomes for patients. The profession's greatest challenge is moving this evidence into practice.

A new imaging modality for intraoperative evaluation of sinus floor augmentation.

The aim of this report was to demonstrate the practicability of a new imaging modality, which allows three-dimensional intraoperative imaging and verification of bone-graft position, and to compare it to the currently available imaging systems. The ARCADIS Orbic 3D, a C-arm-based cone-beam computed tomography scanner developed for intraoperative imaging, was used to examine a previously augmented sinus floor, in order to verify the height and width of the augmentation and to determine whether any of the autogenous and synthetic bone-substitute mixture had penetrated the sinus membrane. Visualization of the entire sinus was possible with the aid of multiplanar reconstructions. Data acquisition and processing took 5 min.

Navigated implantation after microsurgical bone transfer using intraoperatively acquired cone-beam computed tomography data sets.

The use of a combination of intraoperative cone-beam computed tomography (CBCT) and a navigation system via a spinal software platform for the navigated implantation of oral implants after microsurgical bone transfer is described. Intraoperative data sets were generated using Arcadis Orbic 3D (Siemens, Medical Solutions, Erlangen, Germany) and immediately transferred to the VectorVision(2) navigation system (BrainLAB, Feldkirchen, Germany) via the NaviLink interface. In two patients who underwent microsurgical bone transfer for midfacial reconstruction, implants were placed using intraoperatively acquired CBCT data sets for planning and navigated insertion. In both cases, successful realization of the planned implant sites was achieved by the guidance of the drill, leading to rehabilitation of both patients. CBCT data generated by mobile systems are sufficient for the planning of implant position, and can be used for navigated insertion using tools originally developed for spinal surgery.

Functional Outcome of Completely Intracorporeal Robotic Ileal Ureteric Replacement.

OBJECTIVE: To assess perioperative, clinical, and functional outcomes following completely robotic ileal ureter. METHODS: We retrospectively reviewed 7 consecutive patients undergoing completely intracorporeal ileal ureteric replacement between November 2015 and May 2017. One patient had a solitary kidney. A 4-arm technique was used. In 5 patients, additional psoas hitch procedure was performed. Patients had retrograde filling and removal of the ileal stent and transurethral catheter at an average of 14 days postoperatively. Renal ultrasonography, serum analysis, and diuretic renography were performed at follow-up 3 months postoperatively. RESULTS: Mean operative time was 328 ± 66.3 minutes and median estimated blood loss was 100 mL (range 50-200); mean length of the ileal substitute was 20.4 cm (range 18-24). No case was converted to open surgery. In 1 patient, there was a prolonged insufficiency of the pyeloileal anastomosis, requiring prolonged stenting. Apart from that, there were no major complications and no open surgical or endoscopic reinterventions. On 3-month follow-up, all patients presented symptom-free, with no signs of obstruction on ultrasound and significantly improved glomerular filtration rate, creatinine levels, and differential renal function (P = .02, 0.03, and 0.046, respectively). Five patients had a diuretic halftime <10 minutes, 2 had a halftime between 10 and 20 minutes. CONCLUSION: Completely intracorporeal robotic ileal ureteric replacement results in full functional restoration of the upper tract in cases of long defects of the mid and upper ureter.

Clinical characteristics and immunohistochemical analysis of p53, Ki-67 and cyclin D1 in 80 odontogenic keratocysts.

OBJECTIVE: The aim of this study was to evaluate clinical parameters and expression patterns of Ki-67, cyclin D1 and p53 in odontogenic keratocysts. MATERIAL AND METHODS: In this study, fifty-three patients with 80 odontogenic keratocysts were included. The medical records of these patients were reviewed retrospectively. To elucidate the molecular pathogenesis of the disease, the expression of p53, Ki-67 and cyclin D1 was analyzed using immunohistochemistry. RESULTS: A total of 53 patients (mean age 38 years) with a median follow-up of 4.2 years (ranging from 4 days to 14.4 years) were evaluated. The rates of recurrence and post-operative complications varied depending on the surgical approach: cystectomy and peripheral ostectomy led to manageable low rates of complications and recurrence frequency. Immunohistochemical evaluation revealed that all lesions were positive for Ki-67 and cyclin D1 expression. The expression of Ki-67 was associated with the degree of inflammation. Cyclin D1 was expressed significantly higher in syndrome-associated keratocystic lesions. In contrast to non-syndromal lesions, all syndromal lesions expressed p53. CONCLUSION: This investigation demonstrates that the pathogenesis of syndromal keratocysts appears to differ from sporadic odontogenic keratocysts. Additionally, the primary and recurrent non-syndromal keratocysts have a similar etiology, as no differences in the expression patterns of Ki-67, p53 and cyclin D1 were observed.

Free flap surgery in Europe: an interdisciplinary survey.

Free flap surgery is essential for the aesthetic and functional reconstruction of various parts of the body. The aim of this study was to compare current concepts of perioperative flap management between ENT, craniomaxillofacial, and plastic surgeons. A European survey was conducted among 570 surgical departments, covering all aspects of free flap surgery. Focus was placed on antibiotic and antithrombotic drug use, aspects of osseous reconstruction, and flap monitoring strategies. One hundred and seventy-two medical units participated. A broad spectrum of anticoagulant regimens and a trend towards prolonged antibiotic prophylaxis were found. Fixation with (CAD/CAM) reconstruction plates was more popular than monocortical locking with miniplates in the mandible. Visual assessment and Doppler systems were reported to be the most common monitoring modalities. The flap loss rate was stated to be higher after osseous reconstruction. Only a few differences in perioperative flap management were identified between the different surgical fields, and osseous reconstruction appears to be the most challenging.

[Skeletal and dermatological manifestations of the nevoid Basal cell carcinoma syndrome (Gorlin-Goltz syndrome). Results of 8 patients in 12 years]. / Skelettale und kutane Charakteristika des nävoiden Basalzellkarzinomsyndroms (Gorlin-Goltz-Syndrom). Ergebnisse von 8 Patienten aus 12 Jahren.

PURPOSE: In 1960 Gorlin and Goltz defined the nevoid basal cell carcinoma syndrome (NBCCS, Gorlin-Goltz Syndrome) as a syndrome comprising multiple basal cell carcinoma, odontogenic keratocysts, and skeletal anomalies. NBCCS is an autosomal dominantly inherited disease with an estimated prevalence of 1:150,000 and diagnosis of this syndrome is often an accidental finding of radiological investigations. The purpose of this study was to report the varied radiological and dermatological manifestations of our patients affected with NBCCS and to present this rare syndrome as a differential diagnosis of skeletal anomalies. MATERIALS AND METHODS: Between 1994 and 2005 the demographic, clinical, radiological and histological data of 8 patients with NBCCS were retrospectively analyzed. Nevoid basal cell carcinoma syndrome was diagnosed in the event of two major or one major and two minor criteria. The major criteria are more than 2 basal cell carcinoma, odontogenic keratocysts, three or more palmar pits, and calcification of the falx cerebri. RESULTS: Between 1994 and 2005 8 patients (3 females and 5 males) with NBCCS were treated in our departments. The average age at the time of diagnosis of NBCCS was 49.9 years. All patients had a minimum of two major criteria. The major criteria with the most frequency were the basal cell carcinoma (6 patients) and the odontogenic keratocysts (5 patients), followed by the calcification of the falx cerebri and palmoplantar pits (4 patients). There was no gender-related or age-related predilection and only one patient was affected with pain in his fingers which radiologically correlated to small cystic bone lesions ("flame-shaped lucencies"). CONCLUSION: Due to limitations in identification of mutations in the PTCH1 gene, clinical and radiological examination still remains a very important factor in the treatment of patients suffering from NBCCS. The knowledge of the varied skeletal manifestations and constellations is therefore essential and correlates with therapeutic consequences. Often chest, rib, spine, skull, and jaw X-rays show the way. Due to the risk of the development of an associated medulloblastoma, neurological surveillance in 6-month intervals in addition to an annual MRI of the cerebrum up to an age of 7 is strongly recommended.

Validation of a new training tool for ultrasound as a diagnostic modality in suspected midfacial fractures.

The aim of this study was to test a previously described training tool for ultrasound for use as a first-line imaging modality. Navigated sonography was performed in 10 patients with midfacial fractures diagnosed using computed tomography (CT). One examiner ranked his sonographic findings regarding the presence of a fracture on six predefined anatomic landmarks on a scale from 1 to 5. These results were correlated with CT findings by displaying fused images. In all but three patients fractures were correctly identified using sonography. In the remaining three patients the examiner was unable to determine whether a fracture was present or not. Normally, these patients would have been subjected to conventional radiographs. Ultrasound proved to be a reliable first-line imaging modality for the investigation of suspected midfacial fractures in daily clinical practice, resulting in decreased radiation exposure since conventional radiographs are omitted. According to this algorithm, patients with sonographically confirmed midfacial fractures are examined for surgical planning using cone-beam CT.

Learning by doing virtually.

Selective reduction of bone without collateral damage (nerves, teeth) is essential in apicectomy. To test whether skills acquired on a virtual apicectomy simulator (VOXEL-MAN system with integrated force-feedback) are transferable from virtual to physical reality, two groups of trainees were compared. Group 1 received computer-based virtual surgical training before performing an apicectomy in a pig cadaver model. The probability of preserving vital neighboring structures was improved significantly, i.e. six-fold, after virtual surgical training (P<0.001). The average volume of the bony defects created by the trainees of Group 2 (mean: 0.47 ml) was significantly (P<0.001) larger than by the trainees of Group 1 (mean: 0.25 ml). Most importantly, the ability to objectively self-assess performance was significantly improved after virtual training. Training with a virtual apicectomy simulator appears to be effective, and the skills acquired are transferable to physical reality.

Technical and surgical aspects of the sphenopalatine ganglion (SPG) microstimulator insertion procedure.

Cluster headache (CH) is a debilitating, severe form of headache. A novel non-systemic therapy has been developed that produces therapeutic electrical stimulation to the sphenopalatine ganglion (SPG). A transoral surgical technique for inserting the Pulsante SPG Microstimulator into the pterygopalatine fossa (PPF) is presented herein. Technical aspects include detailed descriptions of the preoperative planning using computed tomography or cone beam computed tomography scans for presurgical digital microstimulator insertion into the patient-specific anatomy and intraoperative verification of microstimulator placement. Surgical aspects include techniques to insert the microstimulator into the proper midface location atraumatically. During the Pathway CH-1 and Pathway R-1 studies, 99 CH patients received an SPG microstimulator. Ninety-six had a microstimulator placed within the PPF during their initial procedure. Perioperative surgical sequelae included sensory disturbances, pain, and swelling. Follow-up procedures included placement of a second microstimulator on the opposite side (n=2), adjustment of the microstimulator lead location (n=13), re-placement after initial unsuccessful placement (n=1), and removal (n=5). This SPG microstimulator insertion procedure has sequelae comparable to other oral cavity procedures including tooth extractions, sinus surgery, and dental implant placement. Twenty-five of 29 subjects (86%) completing a self-assessment questionnaire indicated that the surgical effects were tolerable and 90% would make the same decision again.

Intraoperative imaging of zygomaticomaxillary complex fractures using a 3D C-arm system.

After preclinical studies and evaluation of radiation exposures, intraoperative three-dimensional (3D) C-arm based imaging is now available for the facial skeleton. Fourteen patients admitted for surgical treatment of zygomaticomaxillary complex (ZMC) fractures were included in the study. Preoperative diagnostics and surgical treatment were performed as usual. Intraoperatively, after open reduction, a cone-beam computed tomography (CBCT) dataset was generated using the SIREMOBIL Iso-C3D (Siemens Medical Solutions, Erlangen, Germany). After DICOM-import in eFilm Workstation axial, coronal and sagittal reconstructions were evaluated by five examiners with the help of six defined criteria. In our study, secondary reconstructions were available after 6 min, excluding the time needed for the evaluation of the images. Especially the positioning of the isocentre of the SIREMOBIL Iso-C3D proved to be uncomplicated. Because of the size of the datasets, assessment of the symmetry of the malar projection proved difficult. Best scoring results were found regarding the visualization of the fragment position, bony anchorage of the screws and the fitting of the plates. Remarkable was the low level of metal artefacts in primary and secondary reconstructions. In conclusion, our results demonstrate intraoperative CBCT using the SIREMOBIL Iso-C3D suitable for assessment of postoperative results following ZMC reduction.