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The aim of the study was to assess the clinical applicability of robot guided laser osteotomy for clinical application. This is the initial report on 14 consecutive patients requiring an orthognathic procedure with a midface osteotomy (no restrictions made on the surgical indication itself) who have undergone surgery by means of the Cold Ablation Laser Osteotome CARLO® (AOT Advanced Osteotomy Tools, Basle, Switzerland), which is an integrated system, functionally comprising: an Er:YAG laser source, intended to perform osteotomies using cold laser ablation, a robot arm that controls the position of the laser source, an optical tracking device that provides a continuous and accurate measurement of the position of the laser source and of reference elements attached to instruments or bones, a navigation system (software) that is able to read preoperatively defined planned osteotomies, and – under the control of a surgeon – performs the planned osteotomies. Safety was assessed by unimpaired postoperative healing and the absence of device related injuries; performance was assessed as ability to cut the maxilla along the preoperatively planned cutting path with a rage of accuracy of 2mm. Cold ablation robot-guided laser osteotomy could successfully be performed in 14 consecutive patients. No intraoperative complications or technical failure occurred. All osteotomies were within an average deviation of 0.80 mm (±0.26 mm) of the virtually preplanned location. The registration procedure to set up the robot at the beginning of the operation required a mean time of 4.6 min (±5.3min). In this report we describe the effective and successful routine use of Cold ablation robot-guided laser osteotomy in an actual clinical setting. It is a promising technical innovation that has the potential to set new standards for accuracy and safety in orthognathic surgery. [ABSTRACT FROM AUTHOR]

Abstract Purpose The purpose of this study was to provide a quantitative accuracy assessment of soft tissue predictions generated by a computer-aided maxillofacial planning system in patients undergoing orthognathic surgery following the “surgery-first” treatment. Materials and methods For this study, we looked at 16 patients with open bite dentofacial-dysmorphosis who underwent orthognathic surgery. Surgeries were planned using conventional sketches and the newly developed computer-assisted SOTIRIOS planning software (developed by the authors). Validation procedures were performed in the following steps: (1) Standardized registration of the pre- and postoperative CT volumes; (2) Automated adjustment of the bone-related preoperative planning to the actual postoperative bony displacement; (3) Simulation of soft tissue changes according to the definitive bony movements; and (4) Calculation of soft tissue differences between the predicted and the actual 6-month postoperative results by distance mapping. Results The program produced a clinically satisfactory 3D soft tissue prediction, with a mean error of 1.46 mm ± 1.53 mm. The program was suitable for use in virtual surgical planning without technical assistance. Conclusion This study shows that the program is quite accurate, enabling the surgeon to predict the outcome of the soft tissue. This has the potential to promote the routine application of the surgery-first approach in patients suffering from open bite. [ABSTRACT FROM AUTHOR]

• Monoacylglyceride lipase (MGL) deficiency in the tumor microenvironment (TME) of experimental lung cancer and melanoma supports tumor control and progression, respectively. • Depending on the tumor entity MGL deficiency results in differences in infiltrating immune cell composition and activation. • Both the tumor entity and MGL expression affect lipid profiles of experimental solid tumors. We recently described that monoacylglycerol lipase (MGL) is present in the tumor microenvironment (TME), increasing tumor growth. In this study we compare the implications of MGL deficiency in the TME in different tumor types. We show that subcutaneous injection of KP (KrasLSL-G12D/p53fl/fl, mouse lung adenocarcinoma) or B16-F10 cells (mouse melanoma) induced tumor growth in MGL wild type (WT) and knockout (KO) mice. MGL deficiency in the TME attenuated the growth of KP cell tumors whereas tumors from B16-F10 cells increased in size. Opposite immune cell profiles were detected between the two tumor types in MGL KO mice. In line with their anti-tumorigenic function, the number of CD8+ effector T cells and eosinophils increased in KP cell tumors of MGL KO vs. WT mice whereas their presence was reduced in B16-F10 cell tumors of MGL KO mice. Differences were seen in lipid profiles between the investigated tumor types. 2-arachidonoylglycerol (2-AG) content significantly increased in KP, but not B16-F10 cell tumors of MGL KO vs. WT mice while other endocannabinoid-related lipids remained unchanged. However, profiles of phospho- and lysophospholipids, sphingomyelins and fatty acids in KP cell tumors were clearly distinct to those measured in B16-F10 cell tumors. Our data indicate that TME-localized MGL impacts tumor growth, as well as levels of 2-AG and other lipids in a tumor specific manner. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate soft tissue changes after intraoral quadrangular Le Fort II osteotomy (IOQLFII) and correlate those changes to underlying osseous changes.Materials and Methods: Twenty-six non-growing patients with midfacial deficiency and Class III malocclusion were analyzed. A study group of 13 patients who underwent IOQLFII was compared with 13 patients who underwent conventional Le Fort I osteotomy (LFI). After fusion of pre- and postoperative computed tomograms, each patient's hard and corresponding soft tissue changes were measured. Measurement points were defined at 3 levels in the IOQLFII group (infraorbital rim [IR], sinus floor [SF], and lateral incisor tip [LI]) and at 2 levels in the LFI group (SF and LI). Linear models were created to test for correlations between hard and soft tissues.Results: The slope (a1 coefficient) between anteroposterior hard and soft tissue changes was found to be highly significant at each measurement point for all groups. In the IOQLFII group, soft tissue advancement was 69% (confidence interval [CI], 62 to 77%) of the hard tissue advancement at the IR, 90% (CI, 84 to 96%) at the SF, and 73% (CI, 64 to 82%) at the LI. In the LFI group, the corresponding percentages were 90% (83 to 97%) at SF and 84% (77 to 90%) at LI.Conclusion: IOQLFII results in predictable correction of midfacial deficiency. At the IR, bony advancement always resulted in markedly less soft tissue advancement than at the SF level. These results indicate that the planned infraorbital advancement should not be too conservative because soft tissue changes are smaller in this region. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to test the bone thickness and potential screw length for osteosynthesis of condylar base fractures (according to the Loukota classification) with an experimental titanium plate, placed in an ideal position against 2 types of conventional plates.Study Design: After exclusion of completely edentulous mandibles, 28 dentate macerated mandibles available at the time of the study were included. Linear regression models 1 and 2 compared the sums of the 2 cranial bone thicknesses and the 3 caudal thicknesses among the 3 different plate designs, and linear models 3 and 4 tested the bone thickness in the 2 most cranial screw axes.Results: Linear models 1 and 2 revealed significantly higher potential screw lengths for the experimental oblique plate. Equally, linear models 3 and 4 indicated significantly higher bone thickness for the novel oblique plate.Conclusion: The novel proposed oblique plate allows for favorable plate positioning in a biomechanically ideal location with sufficient amounts of local bone for stable plate fixation. When plates with 15-degree angulated screw holes are used, stable bicortical plate fixation can be achieved. [ABSTRACT FROM AUTHOR]

Laman graphs model planar frameworks which are rigid for a general choice of distances between the vertices. There are finitely many ways, up to isometries, to realize a Laman graph in the plane. In a recent paper we provide a recursion formula for this number of realizations using ideas from algebraic and tropical geometry. Here, we present a concise summary of this result focusing on the main ideas and the combinatorial point of view. [ABSTRACT FROM AUTHOR]

[Display omitted] Group 2 innate lymphoid cells (ILC2s) are critical mediators of type 2 respiratory inflammation, releasing IL-5 and IL-13 and promoting the pulmonary eosinophilia associated with allergen provocation. Although ILC2s have been shown to promote eosinophil activities, the role of eosinophils in group 2 innate lymphoid cell (ILC2) responses is less well defined. We sought to investigate the role of eosinophils in activation of ILC2s in models of allergic asthma and in vitro. Inducible eosinophil-deficient mice were exposed to allergic respiratory inflammation models of asthma, such as ovalbumin or house dust mite challenge, or to innate models of type 2 airway inflammation, such as inhalation of IL-33. Eosinophil-specific IL-4/13–deficient mice were used to address the specific roles for eosinophil-derived cytokines. Direct cell interactions between ILC2s and eosinophils were assessed by in vitro culture experiments. Targeted depletion of eosinophils resulted in significant reductions of total and IL-5+ and IL-13+ lung ILC2s in all models of respiratory inflammation. This correlated with reductions in IL-13 levels and mucus in the airway. Eosinophil-derived IL-4/13 was necessary for both eosinophil and ILC2 accumulation in lung in allergen models. In vitro, eosinophils released soluble mediators that induced ILC2 proliferation and G protein–coupled receptor–dependent chemotaxis of ILC2s. Coculture of ILC2s and IL-33–activated eosinophils resulted in transcriptome changes in both ILC2s and eosinophils, suggesting potential novel reciprocal interactions. These studies demonstrate that eosinophils play a reciprocal role in ILC2 effector functions as part of both adaptive and innate type 2 pulmonary inflammatory events. [ABSTRACT FROM AUTHOR]

Bioclimatic conditions are thought to have an impact on the frequency of dental abscesses but previous studies have suffered from small patient cohorts, methodological obstacles, and restriction to a single site resulting in limited geographic and meteorological variability. The aim of the present study was to investigate the influence of environmental temperature and barometric pressure on the frequency of dental abscesses. Three maxillofacial and two dental clinics in Vienna retrospectively provided a total of 19,218 patients with dentoalveolar abscesses who were treated by intraoral incision between 1998 and 2011. Daily records from six local meteorological stations were consulted to assess daily meteorological parameters. Univariate and multivariate hurdle count regression models were fitted to estimate the effect of daily average barometric pressure and temperature on registered abscess frequencies. Temporal confounders causing variance of the observed abscess frequencies – such as weekday, business day, and month – were taken into consideration. On days of low barometric pressure a significant rise in dental abscess frequency was observed, even when adjusting for confounders. Environmental temperature, in contrast, did not show any effect. In conclusion, bioclimatic conditions affect health as low barometric pressure increases the number of patients with dental abscesses. [ABSTRACT FROM AUTHOR]

Purpose In the present study, we report an innovative workflow using polyetheretherketone (PEEK) patient-specific implants for esthetic corrections in the facial region through onlay grafting. The planning includes implant design according to virtual osteotomy and generation of a subtraction volume. The implant design was refined by stepwise changing the implant geometry according to soft tissue simulations. Materials and Methods One patient was scanned using computed tomography. PEEK implants were interactively designed and manufactured using rapid prototyping techniques. Positioning intraoperatively was assisted by computer-aided navigation. Two months after surgery, a 3-dimensional surface model of the patient's face was generated using photogrammetry. Finally, the Hausdorff distance calculation was used to quantify the overall error, encompassing the failures in soft tissue simulation and implantation. Results The implant positioning process during surgery was satisfactory. The simulated soft tissue surface and the photogrammetry scan of the patient showed a high correspondence, especially where the skin covered the implants. The mean total error (Hausdorff distance) was 0.81 ± 1.00 mm (median 0.48, interquartile range 1.11). The spatial deviation remained less than 0.7 mm for the vast majority of points. Conclusions The proposed workflow provides a complete computer-aided design, computer-aided manufacturing, and computer-aided surgery chain for implant design, allowing for soft tissue simulation, fabrication of patient-specific implants, and image-guided surgery to position the implants. Much of the surgical complexity resulting from osteotomies of the zygoma, chin, or mandibular angle might be transferred into the planning phase of patient-specific implants. [ABSTRACT FROM AUTHOR]

PURPOSE: Registration of preoperative targeting information for the intraoperative situation is a crucial step in computer-assisted surgical interventions. Point-to-point registration using acrylic splints is among the most frequently used procedures. There are, however, no generally accepted recommendations for sterilization of the splint. An appropriate method for the thermolabile splint would be hydrogen peroxide-based plasma sterilization. This study evaluated the potential deformation of the splint undergoing such sterilization. Deformation was quantified using image-processing methods applied to computed tomographic (CT) volumes before and after sterilization. MATERIALS AND METHODS: An acrylic navigation splint was used as the study object. Eight metallic markers placed in the splint were used for registration. Six steel spheres in the mouthpiece were used as targets. Two CT volumes of the splint were acquired before and after 5 sterilization cycles using a hydrogen peroxide sterilizer. Point-to-point registration was applied, and fiducial and target registration errors were computed. Surfaces were extracted from CT scans and Hausdorff distances were derived. Effectiveness of sterilization was determined using Geobacillus stearothermophilus. RESULTS: Fiducial-based registration of CT scans before and after sterilization resulted in a mean fiducial registration error of 0.74 mm; the target registration error in the mouthpiece was 0.15 mm. The Hausdorff distance, describing the maximal deformation of the splint, was 2.51 mm. Ninety percent of point-surface distances were shorter than 0.61 mm, and 95% were shorter than 0.73 mm. No bacterial growth was found after the sterilization process. CONCLUSION: Hydrogen peroxide-based low-temperature plasma sterilization does not deform the splint, which is the base for correct computer-navigated surgery. [ABSTRACT FROM AUTHOR]

Purpose: Registration of preoperative targeting information for the intraoperative situation is a crucial step in computer-assisted surgical interventions. Point-to-point registration using acrylic splints is among the most frequently used procedures. There are, however, no generally accepted recommendations for sterilization of the splint. An appropriate method for the thermolabile splint would be hydrogen peroxide–based plasma sterilization. This study evaluated the potential deformation of the splint undergoing such sterilization. Deformation was quantified using image-processing methods applied to computed tomographic (CT) volumes before and after sterilization. Materials and Methods: An acrylic navigation splint was used as the study object. Eight metallic markers placed in the splint were used for registration. Six steel spheres in the mouthpiece were used as targets. Two CT volumes of the splint were acquired before and after 5 sterilization cycles using a hydrogen peroxide sterilizer. Point-to-point registration was applied, and fiducial and target registration errors were computed. Surfaces were extracted from CT scans and Hausdorff distances were derived. Effectiveness of sterilization was determined using Geobacillus stearothermophilus. Results: Fiducial-based registration of CT scans before and after sterilization resulted in a mean fiducial registration error of 0.74 mm; the target registration error in the mouthpiece was 0.15 mm. The Hausdorff distance, describing the maximal deformation of the splint, was 2.51 mm. Ninety percent of point-surface distances were shorter than 0.61 mm, and 95% were shorter than 0.73 mm. No bacterial growth was found after the sterilization process. Conclusion: Hydrogen peroxide–based low-temperature plasma sterilization does not deform the splint, which is the base for correct computer-navigated surgery. [ABSTRACT FROM AUTHOR]

PURPOSE: The present study was conducted to evaluate the effect of platelet-rich plasma (PRP) on new bone formation and remodeling after grafting of the maxillary sinus with an algae-derived hydroxyapatite AlgOss/C Graft/Algipore. MATERIALS AND METHODS: Fourteen consecutive patients with severely atrophic maxillae underwent uni- or bilateral grafting of the maxillary sinus with a mixture of collected bone, algae-derived hydroxyapatite AlgOss/C Graft/Algipore (ratio 1:10), and a combined addition of PRP and thrombin (Tissucol Kit; Baxter, Vienna, Austria) to allow for fast clotting. After an average healing period of 7.1 months bone samples were retrieved. Patients from a former consecutive series treated without PRP served as control group. Statistical analysis was done by Welch 2-sample t test and mixed linear model testing. RESULTS: In the coronal specimen portions, mean values for newly formed bone area, biomaterial area and marrow space of 32.2% ± 10.4%, 20.1% ± 13.0%, and 47.7% ± 8.5% were found with PRP, respectively. In the control group the corresponding values were 27.6% ± 13.4%, 20.3% ± 12.9%, and 52.1% ± 9.3%. In the apical specimen portions in the PRP group, the newly formed bone area, biomaterial area, and marrow space was 25.7% ± 15.0%, 23.4% ± 14.9%, and 50.9% ± 12.5%, respectively. The corresponding values in the control group were 17.0% ± 8.6%, 34.5% ± 11.2%, and 48.5% ± 8.5%. CONCLUSIONS: Statistical evaluation of the samples proved significantly better overall resorption of algae-derived hydroxyapatite AlgOss/C Graft/Algipore and increased new bone formation when PRP was used, especially in the apical region. [ABSTRACT FROM AUTHOR]

Purpose: The present study was conducted to evaluate the effect of platelet-rich plasma (PRP) on new bone formation and remodeling after grafting of the maxillary sinus with an algae-derived hydroxyapatite AlgOss/C Graft/Algipore. Materials and Methods: Fourteen consecutive patients with severely atrophic maxillae underwent uni- or bilateral grafting of the maxillary sinus with a mixture of collected bone, algae-derived hydroxyapatite AlgOss/C Graft/Algipore (ratio 1:10), and a combined addition of PRP and thrombin (Tissucol Kit; Baxter, Vienna, Austria) to allow for fast clotting. After an average healing period of 7.1 months bone samples were retrieved. Patients from a former consecutive series treated without PRP served as control group. Statistical analysis was done by Welch 2-sample t test and mixed linear model testing. Results: In the coronal specimen portions, mean values for newly formed bone area, biomaterial area and marrow space of 32.2% ± 10.4%, 20.1% ± 13.0%, and 47.7% ± 8.5% were found with PRP, respectively. In the control group the corresponding values were 27.6% ± 13.4%, 20.3% ± 12.9%, and 52.1% ± 9.3%. In the apical specimen portions in the PRP group, the newly formed bone area, biomaterial area, and marrow space was 25.7% ± 15.0%, 23.4% ± 14.9%, and 50.9% ± 12.5%, respectively. The corresponding values in the control group were 17.0% ± 8.6%, 34.5% ± 11.2%, and 48.5% ± 8.5%. Conclusions: Statistical evaluation of the samples proved significantly better overall resorption of algae-derived hydroxyapatite AlgOss/C Graft/Algipore and increased new bone formation when PRP was used, especially in the apical region. [ABSTRACT FROM AUTHOR]

Introduction: This retrospective study comprises an exploratory analysis of 10 years of surgical treatment of symphysis (S) and parasymphysis/body (P/B). Correlations of complications, as well as dependencies of surgical concepts, are investigated. Materials and methods: All surgically treated patients in the period of 1995 to 2005 with at least one mandibular fracture mesial to the mandibular angle were included in this study. A total of 63 patients (46 men, 17 women) with 63 symphysis fractures were included and 497 patients (369 men, 128 women) with 553 P/B were included; 99.27% (549) of these fractures were included in the study, 4 had to be dismissed because of inconclusive documentation. Results: Of patients with P/B, 96.04% were successfully treated with 1 open reduction, 3.76% had 2, and 0.20% had 3 surgeries. Of the surgically treated patients, 75.77% (416) were completely free of complications, whereas the other 24.23% of the P/B showed 1 or more complications. The main complication was mild nerve damage (24.8%). Osteosynthesis failure rate (OFR) was 2.4% (7 of 298) for 2 miniplates, 5.7% (3 of 53) for 1 tension screw, and 8.4% (9 of 107) for 1 miniplate. Regarding OFR, 2 miniplates showed to be superior in a Fisher exact test (P = .018, adjusted P = .132). Symphysis fractures were completely free of complications in 81.8% and showed 2 major complications, i.e., 1 severe nerve damage and 1 osteosynthesis failure. Discussion: This study has the limitations of a retrospective study. Conclusion: A high success rate of open reduction and osteosynthesis with 2 miniplates can be guaranteed. [ABSTRACT FROM AUTHOR]

Background: Osteosynthesis failure rates of 11.3% with 1 miniplate, 6.7% with 2 miniplates, and 4.4% with a single Medartis condyle plate were reported in previous studies of our clinic. Current science is still focused on the osteosynthesis material. Besides clinical parameters, conventional radiographs are still the first choice to detect osteosynthesis failures. This study scrutinized several factors assessable in postoperative orthopantomographs which might elevate the risk of osteosynthesis failure. Study design: A total of 136 patients (22 with osteosynthesis failure, 114 without) with 151 mandibular condyle fractures were included in this study. Eight parameters were assessed in postoperative orthopantomographs. Results: The best predictor of osteosynthesis failure was a simplified concept of ramus height. In cases of reduced or normal ramus height, the odds of osteosynthesis failure was significantly (P = .000001) reduced to a 10th. Isolated fractures were significantly more error prone (P = .0009). Conclusions: Postoperative orthopantomographs depict factors which increase the risk of osteosynthesis failure. [Copyright &y& Elsevier]

Purpose: We evaluated an innovative approach for conventional surgical or transmucosal implantation applying backward planning with bone oriented crown down implant positions, followed by immediate restoration. Materials and Methods: Our workflow combined computer-assisted preoperative planning with the well-known intraoperative handling of surgical templates. To guarantee optimal accuracy, the complete process was bone borne, not soft tissue borne. Furthermore, in this concept, the definite prosthesis was manufactured on a plaster cast and fixed with technical implants inserted into the model using the same drilling template applied for intraoperative guidance of the drill. This bone-based workflow avoids the accumulation of errors throughout all steps of the treatment. In the present study, we have provided a concise quantitative quality control using 4 in vivo implants. This goal was accomplished by image matching of the preoperative plan with the corresponding postoperative computed tomography scan, applying descriptive statistics, the 1-sample t test, and the Student t test. Results: Statistical evaluation showed that the bone-borne drilling template provides sufficient accuracy for immediate restoration with the definite prosthesis at the end of the operation. Deviation in the apex plane was 0.8 ± 0.42 mm, with 0.33 at the maximum. The angular deviation was 3.18° ± 0.78°. Conclusions: Our workflow is a promising approach with respect to handling, accuracy, and intraoperative safety. [Copyright &y& Elsevier]

BACKGROUND: Surgical treatment of mandibular neck fractures is frequently associated with postoperative complications. This study aims at an in-depth analysis of complication rates of surgically treated mandibular neck fractures. METHODS: All treated patients (264 male, 103 female patients, with 429 mandibular neck fractures) of the Vienna University Clinic of Maxillofacial Surgery in the period of 1995 to 2005 with at least 1 mandibular neck fracture were included. RESULTS: Of surgically treated fractures, 94.8% healed successfully after 1 open reduction, 4.4% had 2, and 0.8% had 3 open reductions. Osteosynthesis failure was 11.3% for 1 miniplate, 6.7% for 2 miniplates, and 8.5% for 1 lag screw. Of the surgically treated, 53 (21.3%) had 1 complication, 12 (4.8%) had 2, and 4 (1.6%) had 3 complications. Comparing isolated and mandibular neck fractures combined with other mandibular fractures the risk of suffering osteosynthesis failure is 3.59 in case of isolated (P = .004). CONCLUSIONS: Predominant causes of revision surgery are osteosynthesis failure, pseudarthrosis, and malposition. [ABSTRACT FROM AUTHOR]

Background: Surgical treatment of mandibular neck fractures is frequently associated with postoperative complications. This study aims at an in-depth analysis of complication rates of surgically treated mandibular neck fractures. Methods: All treated patients (264 male, 103 female patients, with 429 mandibular neck fractures) of the Vienna University Clinic of Maxillofacial Surgery in the period of 1995 to 2005 with at least 1 mandibular neck fracture were included. Results: Of surgically treated fractures, 94.8% healed successfully after 1 open reduction, 4.4% had 2, and 0.8% had 3 open reductions. Osteosynthesis failure was 11.3% for 1 miniplate, 6.7% for 2 miniplates, and 8.5% for 1 lag screw. Of the surgically treated, 53 (21.3%) had 1 complication, 12 (4.8%) had 2, and 4 (1.6%) had 3 complications. Comparing isolated and mandibular neck fractures combined with other mandibular fractures the risk of suffering osteosynthesis failure is 3.59 in case of isolated (P = .004). Conclusions: Predominant causes of revision surgery are osteosynthesis failure, pseudarthrosis, and malposition. [Copyright &y& Elsevier]

Purpose: Large-scale studies assessing complication rates and correlation of complications are still missing considering different fracture locations in the mandible. In the present retrospective study, complication rates of mandibular angle fractures treated by open reduction were assessed. Materials and Methods: Three hundred twenty-two patients (259 men, 63 women) with 335 surgically treated mandibular angle fractures were included in this study. Results: Fractures were caused by fights (46.6%), falls (19.2%), traffic accidents (14.6%), sports (11.9%), wisdom tooth removal (7.3%), and 0.9% other causes. Successful treatment occurred in 93.69% of fractures with 1 open reduction and in 6.31% with 2 open reductions. Of surgically treated patients, 71.47% (238) were completely free of complications. A detailed complication correlation matrix is given in the text. Ninety-five fractures treated with 1 miniplate, 170 with 2 miniplates, and 70 with other osteosynthesis concepts were compared regarding osteosynthesis failure and pseudarthrosis. Conclusion: Similar osteosynthesis failure rates were shown for 1 miniplate and 2 miniplates. [Copyright &y& Elsevier]

Abstract: This study reports measurements of dental casts in patients up to 6 months of age with bilateral complete cleft lip and palate (BCLP). 25 mouth casts of newborns with BCLP were selected from the hospital archive. They were measured independently by two examiners who assigned numbers to each measurement, referring to the expected reproducibility. The investigators also classified each dental cast according to an established score. The absolute values of all measured distances (P-P′, L-C1-C2-T, L′-C1′-C2′-T′, P-L, P′-L′, L-L′, C1-C1′, C2-C2′, Q1-Q1′, Q2-Q2′, T-T′, I-Q1Q1′, I-Q2Q2′, I-TT′) are reported. Inter-observer reproducibility was acceptable with total measurement errors ranging from 0.5 to 1.4mm. Most reliability scores, ranging from 1 (very high) to 5 (very low), showed a mean between 2 and 3 (min 2.17; max 3.16). The two examiners rated only one patient differently, according to the applied classification scheme. The absolute measurement values of the two classification systems accorded with the literature. This is the first study to measure the distances according to an established protocol in BCLP patients. The measurements between certain landmarks are more precise than others; it may be possible to use the more precise points for a longitudinal study from birth to 18 years. [Copyright &y& Elsevier]

Purpose: In this study we report our experiences with the treatment of midfacial fractures and various other indications in regions with low load bearing (eg, dysmorphias) using the biodegradable Osteosynthesis System (SonicWeld Rx by KLS Martin, Tuttlingen, Germany), comprising biomechanical and histological aspects. Patients and Methods: Seventy-five patients were included in this study. We describe the application of this system for the treatment of fractures of the zygomamaxillary complex, frontal bone impression fractures, surgical treatment of mukocele in the frontal sinus, isolated fractures of the orbital floor, complex midfacial trauma and bone cap fixation, craniosynostoses, and fixation of a distracted bone fragment. Results: The pin insertion could be finished with a total failure rate of lower than 5%. In 3 patients, soft tissue swellings in regions with less subcutaneous fat were observed 6 to 8 months postoperatively. No fracture dislocations occurred. Scanning electron micrograph of the experimentally acquired connection between the resorbable plate and 2 pins clearly demonstrates a tight and reliable fusion to bone, both at the cortical as well as at the spongy compartment. Conventional histology leads to corresponding findings as scanning electron micrography, and shows a close fusion between all components. Conclusion: This retrospective study shows the general feasibility, sufficient mechanical stability, and efficient intraoperative handling of this angle-stable, ultrasonic-guided resorbable Osteosynthesis System (ResorbX and SonicWeld Rx) for a wide variety of indications in craniomaxillofacial surgery. [Copyright &y& Elsevier]

Objective: One step toward motion analysis of the temporomandibular joint is pseudodynamic magnetic resonance imaging (i.e., with stepwise mouth opening controlled by a Burnett device). This study intends to clarify whether and how pseudodynamic motion differs from natural motion. Furthermore, the fixing efficiency (i.e., the reliability of the mechanical connection to the jaw) of the Burnett device was tested. Study design: In 10 patients we recorded pseudodynamic opening motions by means of MRI and optical tracking technology (as known from image-guided surgery) synchronously; natural opening motions by spatiotemporal tracking only. The MRI was used to allow for interpretation of the pseudodynamic motion as recorded by means of optoelectronic tracking. Results: In 3 subjects the pseudodynamic differed from the natural opening in occurrence of a loop (i.e., a short backward motion of the condyle during the opening process that results from the application of the Burnett device and does not correspond to a natural jaw movement). Fifty percent of the opening steps showed unintended motion and thus did not keep the mandible still during the MRI scan. Conclusion: A method was provided to detect motion during MRI scan using optoelectronic tracking. Pseudodynamic motion may differ from natural motion. [Copyright &y& Elsevier]

Background & Aims: Hydrogen sulfide (H2S) has been suggested as a novel gasomediator. We explored its unknown neuromodulatory role in human and guinea-pig colon. Methods: We used immunohistochemistry to detect H2S-producing enzymes cystathionine γ-lyase (CSE) and cystathionine β-synthase (CBS) in enteric neurons, Ussing chambers to measure mucosal ion secretion, and neuroimaging with voltage- and Ca++-sensitive dyes to record H2S effects on guinea-pig and human enteric neurons. Results: More than 90% of guinea-pig and human submucous and myenteric neurons were colabeled for CSE and CBS. Myenteric interstitial cells of Cajal were CSE-immunoreactive. The exogenous H2S donor NaHS (0.2–2.5 mmol/L) concentration-dependently increased chloride secretion in human and guinea-pig submucosa/mucosa preparations, but not in the colonic epithelial cell line T84. The secretory response was reduced significantly by tetrodotoxin (0.5 μmol/L), capsaicin desensitization (10 μmol/L), and the transient receptor potentials vanilloid receptor 1 antagonist capsazepine (10 μmol/L). The endogenous H2S donor L-cysteine also induced secretion that was diminished significantly by capsaicin desensitization, the CBS inhibitor amino-oxyacetic acid, and the CSE inhibitor propargylglycine. NaHS increased spike discharge in 23% of guinea-pig and 36% of human submucous neurons, but had no effect on Ca++ mobilization in cultured guinea-pig enteric neurons. This excitatory response was reduced significantly by capsaicin desensitization and capsazepine, but not by glibenclamide (10 μmol/L). Conclusions: The presence of H2S-producing enzymes in human and guinea-pig enteric neurons, the excitatory action on enteric neurons, and the prosecretory effects of NaHS suggest H2S as a novel gut-signaling molecule. Its action mainly involves transient receptor potentials vanilloid receptor 1 receptors on extrinsic afferent terminals, which in turn activate enteric neurons. [Copyright &y& Elsevier]

Objective: To assess whether computer-guided flapless transmucosal implant bed preparation without mucosal punching allows placement of dental implants in edentulous mandibles. Study design: Twenty patients with fully edentulous mandibles (11 male; 9 female) were included in the study. Each patient was scheduled to receive 4 screw-shaped Ankylos (Dentsply Friadent, Mannheim, Germany) implants in the interforaminal region. The StealthStation Treon navigation system (Medtronic, Minnesota, MN) was used for computer-guided drilling. Using conventional implant drills the mucosa was penetrated without flap elevation or mucosal punching. The study protocol did not allow direct visualization of the bone surface during surgery. Results: For 78 implants (97.5%) the preoperative plan could be transfered to the patient by intraoperative navigation with a mean deviation of 0.9 mm (Implant tip 0.8 ± 0.6 mm; coronal implant end 1.1 ± 0.7 mm) as measured by comparing pre- and postoperative computerized tomography images. Two implants (2.5 %) were not primarily stable and failed to osseointegrate. Conclusions: Computer-guided transmucosal interforaminal implant placement without mucosal punching is a precise and predictable procedure. It is, however, not yet suitable for all bone morphologies. Future developments may include miniaturization of hardware and simplification of the drilling procedure. [Copyright &y& Elsevier]

Purpose: To evaluate the feasibility and accuracy of a new method for planning and realizing zygomatic osteotomies in cases of established post-traumatic deformities using stereolithographic (SL) models and computer assisted navigation. Patients and Methods: In 5 patients, osteotomy and repositioning of the zygomatic complex was planned using SL models. The desired position of the zygoma in the patient was determined by fixing individualized osteosynthesis plates to predefined screw positions. The SL model and the patient were registered to the same 3-dimensional computed tomography data set via an occlusal reference frame on the patient and corresponding reference markers on the model. Prebent osteosynthesis plates from the surgical simulation on the model were fixed to corresponding screw positions on the patient, which were located by computer-assisted navigation. Evaluation of accuracy was performed by image fusion of postoperative computed tomography scans of the model and the patient. Results: Clinical outcome was satisfactory in all cases. The evaluation by image fusion showed alignment of the patient’s and the model’s zygoma in 4 of 5 cases. Mean measured distance between screw positions in the models and the patients were 1.1 ± 0.3 mm for 44 screws. In 1 patient the treatment plan was changed intraoperatively because of unforeseen soft tissue limitations. Conclusion: Point-to-point navigation is an accurate method to transfer the planning of a complex osteotomy from the SL model to the actual surgical procedure. Surgery is facilitated considerably because repositioning and osteosynthesis are achieved in 1 step. [Copyright &y& Elsevier]

Purpose: In this work the experiences from 50 telemedically supported treatments in craniomaxillofacial surgery are summarized and different setups for their technical realization are described. Furthermore, for the first time the innovative UMTS (universal mobile telecommunication system) is applied for the transmission of arthroscopic videos of the temporomandibular joint and other craniomaxillofacial structures. Materials and Methods: The combination of computer-assisted navigation technology in augmented reality environments with telecommunication is used for execution of interactive stereotaxic teleconsultation. Furthermore, treatments without navigation are telemedically supported. This study is composed of 4 technical system configurations: 1) integrated services digital network (ISDN)-based videoconferencing without remote control of the navigation computer; 2) transmission control protocol/internet protocol (TCP/IP)-based interactive teleconsultation via bundled ISDN lines (including remote control of the navigation computer); 3) TCP/IP-based interactive teleconsultation via network; 4) combination of TCP/IP-connection and ISDN-based videoconferencing. The telemedically supported treatments are: orbitozygomatic osteotomies, positioning of the mandibular condyle in orthognathic surgery, insertion of implants, positioning of the maxilla in orthognathic surgery, distraction osteogenesis, arthroscopies of the temporomandibular joint, and operation simulations on stereolithographic models. The surgical interventions are evaluated on a 5-level system performance scale from the technical point of view. In a separate trial 20 videosequences of arthroscopies of the temporomandibular joint are transmitted via UMTS cellular phones and independently evaluated by 3 experts (ie, a total of 60 streamings) to investigate feasibility of this technology in the field of craniomaxillofacial surgery. Results: In the years from 1996 to 2002 a total of 50 treatments were telemedically supported. All intraoperative applications were successfully finished; 48 of 60 UMTS transmissions were finished without any interruptions in constant quality, slight interruptions were observed in 8 tests, and a complete breakdown was observed during 4 streamings that required a restart of the transmission. Resolution was sufficient to diagnose even tiny anatomic structures inside the temporomandibular joint, but orientation was hardly recognizable. Conclusion: In many applications telecommunication technology can contribute to a quality improvement in cranio- and maxillofacial surgery because of the global availability of specialized knowledge. The required technical expenditure for teleconsultation crucially depends on the infrastructure that is already available at the clinic and the remote site. UMTS is a promising technology with the potential to be valuable in numerous craniomaxillofacial applications. [Copyright &y& Elsevier]

Purpose: In planning intraoral quadrangular Le Fort II osteotomy (IQLFIIO), simulation of hard and soft tissue changes will be important at the infraorbital, Le Fort I, and incisor level. The aim of our study was to evaluate a new method for visualization and quantification.Materials and Methods: Three different methods of quantification were compared: the point-to-point (PTP) measurement, which has been viewed as the reference standard; part comparison analysis (PCA); and a new method, the midfacial advancement line (MFAL) measurement. We performed a measurement comparison study using the Bland-Altman method to measure agreement and enrolled patients with midfacial deficiency and Class III malocclusion who had undergone IQLFIIO. The primary predictor variable was the method of measurement. The primary outcome variable was the amount of midfacial advancement. We also investigated the time required, visualization quality, and interobserver agreement.Results: The sample included 12 subjects with a mean age of 21.6 years; 7 patients were male. The PTP and MFAL showed no significant observer dependence. The advancement measured with PTP and MFAL showed no significant differences. However, the advancement measured using MFAL and PCA showed a significant difference. The highest rating of visualization was found for MFAL. The time requirements were similar for all 3 methods.Conclusions: Our results have shown that the MFAL is a suitable method for visualization and quantification of soft and hard tissue changes at all 3 face levels in 1 image. It could be a valuable tool for virtual planning of midfacial advancement surgery. [ABSTRACT FROM AUTHOR]

Objective: In this study we report on finite element calculation to verify the mechanical stability induced by the new geometry of a novel condylar process plate. We report our clinical experiences in the treatment of condylar process fractures using the novel plate. The plate has been designed according to finite element calculations in order to optimize mechanical stability and stiffness. The potential influence of this plate on the postoperative complication rate was assessed. Study design: Thirty-five mandibular condylar process fractures in 30 patients (20 male, 10 female, age: 34.3 ± 11.5 years) were treated with the Modus condylar process plates (Medartis, Basle, Switzerland) and are included in this study. The time periods for postoperative follow-ups were 6 weeks and 6 months. Results: No plate fractures occurred and there was no injury to the facial nerve. In one patient a screw loosening was observed. Two patients showed inadequate reduction without functional impairment. Conclusion: The newly developed condylar process plate proved to provide sufficient mechanical stiffness to avoid plate fractures. The postoperative complication rate can be reduced significantly. Statistical comparison to other osteosynthesis methods of the condylar process was performed and showed significant differences (single miniplates: P = .006 and minidynamic compression plates: P = .055). We conclude that a single Modus condylar process plate shows results comparable to 2 miniplates. [Copyright &y& Elsevier]