The Experts below are selected from a list of 186 Experts worldwide ranked by ideXlab platform
Heinztheo Lubbers - One of the best experts on this subject based on the ideXlab platform.
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evaluation of two Dental registration Splint techniques for surgical navigation in cranio maxillofacial surgery
Journal of Cranio-maxillofacial Surgery, 2014Co-Authors: Dominik Venosta, Astrid L Kruse, Heinztheo Lubbers, Klaus Wilhelm Grätz, Felix Matthews, Martin Lanzer, Thomas GanderAbstract:BACKGROUND: Surgical navigation requires precise registration of the pre-operative image dataset to the patient in the operation theatre. Different marker-based and marker-free registration techniques are available, each of them with advantages and disadvantages regarding precision and clinical handling. In this model study, the precision of two Dental Splint techniques for marker-based registration is analyzed. MATERIALS AND METHODS: A synthetic full-size human skull was registered with its cone beam computed tomography dataset using (a) a Dentally-mounted "rapid" occlusal Splint with five titanium screws directly attached to the Splint, (b) an "extender", a Dentally-mounted occlusal Splint with similar fiducials fixed to an extension of the Splint. The target registration error was measured for 170 landmarks distributed over the viscero- and neurocranium in 10 repeats per Splint type using the Vector Vision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical evaluations were performed per anatomical region. RESULTS: In the periorbital region, the rapid Splint, with an average deviation of 1.50 mm (SD = 0.439) showed greater accuracy than the extender with 1.76 mm (SD = 0.525). The viscerocranial results for both Splints were similar (extender 1.84 mm, SD = 0.559, rapid occlusal Splint 1.86 mm, SD = 0.686). In the cranial vault region, registration with the extender (2.33 mm, SD = 0.685) proved to be more precise than with the rapid Splint (2.86 mm, SD = 0.929). CONCLUSIONS: Due to the more compact dimension of the rapid occlusal Splint, errors close to the Splint were smaller compared to the extender technique. The advantage of greater distances between the registration fiducials on the extender is particularly important in areas such as the orbital roof, the cranial vault, and the lateral skull base.
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point to point registration with mandibulo maxillary Splint in open and closed jaw position evaluation of registration accuracy for computer aided surgery of the mandible
Journal of Cranio-maxillofacial Surgery, 2012Co-Authors: Cyrill Bettschart, Astrid L Kruse, Joachim A Obwegeser, Heinztheo Lubbers, Klaus Wilhelm Grätz, Wolfgang Zemann, Felix MatthewsAbstract:Abstract Introduction Computer navigation plays an increasingly important role in craniomaxillofacial surgery. The difficulties in computer navigation at the craniomaxillofacial site lie in the accurate transmission of the dataset to the operating room. This study investigates the accuracy of the Dental-Splint registration method for the skull, midface, and mandible. Material and methods A synthetic human skull model was prepared with landmarks and scanned with cone beam computer tomography (CBCT). Two registration Splints fixed the mandible against the viscerocranium in two different positions (closed vs. open). The target registration error was computed in all 278 landmarks spread over the entire skull and mandible in 10 repeated measurements using the VectorVision 2 (BrainLAB Inc., Feldkirchen, Germany) navigation system. Results If registered in the closed position an average precision of 2.07mm with a standard deviation (SD) of 0.78mm was computed for all landmarks distributed over the whole skull. Registration in the open position resulted in an average precision of 1.53mm (SD=0.55mm). For single landmarks the precision decreases linearly with distance from the reference markers. The longer the three-dimensional distance between the registration points, the more precise the computer navigation is, mainly in the most posterior area of the cranium. Conclusion Our findings in the cranium are comparable with those of other studies. Artificial fixation of the lower jaw via Splint seems to introduce no additional error. The registration points should be as far apart from each other as possible during navigation with the Splint.
Felix Matthews - One of the best experts on this subject based on the ideXlab platform.
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evaluation of two Dental registration Splint techniques for surgical navigation in cranio maxillofacial surgery
Journal of Cranio-maxillofacial Surgery, 2014Co-Authors: Dominik Venosta, Astrid L Kruse, Heinztheo Lubbers, Klaus Wilhelm Grätz, Felix Matthews, Martin Lanzer, Thomas GanderAbstract:BACKGROUND: Surgical navigation requires precise registration of the pre-operative image dataset to the patient in the operation theatre. Different marker-based and marker-free registration techniques are available, each of them with advantages and disadvantages regarding precision and clinical handling. In this model study, the precision of two Dental Splint techniques for marker-based registration is analyzed. MATERIALS AND METHODS: A synthetic full-size human skull was registered with its cone beam computed tomography dataset using (a) a Dentally-mounted "rapid" occlusal Splint with five titanium screws directly attached to the Splint, (b) an "extender", a Dentally-mounted occlusal Splint with similar fiducials fixed to an extension of the Splint. The target registration error was measured for 170 landmarks distributed over the viscero- and neurocranium in 10 repeats per Splint type using the Vector Vision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical evaluations were performed per anatomical region. RESULTS: In the periorbital region, the rapid Splint, with an average deviation of 1.50 mm (SD = 0.439) showed greater accuracy than the extender with 1.76 mm (SD = 0.525). The viscerocranial results for both Splints were similar (extender 1.84 mm, SD = 0.559, rapid occlusal Splint 1.86 mm, SD = 0.686). In the cranial vault region, registration with the extender (2.33 mm, SD = 0.685) proved to be more precise than with the rapid Splint (2.86 mm, SD = 0.929). CONCLUSIONS: Due to the more compact dimension of the rapid occlusal Splint, errors close to the Splint were smaller compared to the extender technique. The advantage of greater distances between the registration fiducials on the extender is particularly important in areas such as the orbital roof, the cranial vault, and the lateral skull base.
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point to point registration with mandibulo maxillary Splint in open and closed jaw position evaluation of registration accuracy for computer aided surgery of the mandible
Journal of Cranio-maxillofacial Surgery, 2012Co-Authors: Cyrill Bettschart, Astrid L Kruse, Joachim A Obwegeser, Heinztheo Lubbers, Klaus Wilhelm Grätz, Wolfgang Zemann, Felix MatthewsAbstract:Abstract Introduction Computer navigation plays an increasingly important role in craniomaxillofacial surgery. The difficulties in computer navigation at the craniomaxillofacial site lie in the accurate transmission of the dataset to the operating room. This study investigates the accuracy of the Dental-Splint registration method for the skull, midface, and mandible. Material and methods A synthetic human skull model was prepared with landmarks and scanned with cone beam computer tomography (CBCT). Two registration Splints fixed the mandible against the viscerocranium in two different positions (closed vs. open). The target registration error was computed in all 278 landmarks spread over the entire skull and mandible in 10 repeated measurements using the VectorVision 2 (BrainLAB Inc., Feldkirchen, Germany) navigation system. Results If registered in the closed position an average precision of 2.07mm with a standard deviation (SD) of 0.78mm was computed for all landmarks distributed over the whole skull. Registration in the open position resulted in an average precision of 1.53mm (SD=0.55mm). For single landmarks the precision decreases linearly with distance from the reference markers. The longer the three-dimensional distance between the registration points, the more precise the computer navigation is, mainly in the most posterior area of the cranium. Conclusion Our findings in the cranium are comparable with those of other studies. Artificial fixation of the lower jaw via Splint seems to introduce no additional error. The registration points should be as far apart from each other as possible during navigation with the Splint.
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Comparison of different registration methods for surgical navigation in cranio-maxillofacial surgery.
Journal of Cranio-maxillofacial Surgery, 2008Co-Authors: Heinz-theo Luebbers, Joachim A Obwegeser, Peter Messmer, Roger A. Zwahlen, Ron Kikinis, Klaus W. Graetz, Felix MatthewsAbstract:BACKGROUND: Surgical navigation requires registration of the pre-operative image dataset with the patient in the operation theatre. Various marker and marker-free registration techniques are available, each bearing an individual level of precision and clinical practicability. In this study the precision of four different registration methods in a maxillofacial surgical setting is analyzed. MATERIALS AND METHODS: A synthetic full size human skull model was registered with its computer tomography-dataset using (a) a Dentally mounted occlusal Splint, (b) the laser surface scanning, (c) five facial bone implants and (d) a combination of Dental Splint and two orbital bone implants. The target registration error was computed for 170 landmarks spread over the entire viscero- and neurocranium in 10 repeats using the VectorVision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical analyses were performed by anatomical region. RESULTS: An average precision of 1mm was found for the periorbital region irrespective of registration method (range 0.6-1.1mm). Beyond the mid-face, precision linearly decreases with the distance from the reference markers. The combination of Splint with two orbital bone markers significantly improved precision from 1.3 to 0.8mm (p
Xiaojun Chen - One of the best experts on this subject based on the ideXlab platform.
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development of a computer aided design software for Dental Splint in orthognathic surgery
Scientific Reports, 2016Co-Authors: Xiaojun Chen, Yiting Sun, Constantinus Politis, Lu Xu, Xing Li, Jan EggerAbstract:In the orthognathic surgery, Dental Splints are important and necessary to help the surgeon reposition the maxilla or mandible. However, the traditional methods of manual design of Dental Splints are difficult and time-consuming. The research on computer-aided design software for Dental Splints is rarely reported. Our purpose is to develop a novel special software named EasySplint to design the Dental Splints conveniently and efficiently. The design can be divided into two steps, which are the generation of initial Splint base and the Boolean operation between it and the maxilla-mandibular model. The initial Splint base is formed by ruled surfaces reconstructed using the manually picked points. Then, a method to accomplish Boolean operation based on the distance filed of two meshes is proposed. The interference elimination can be conducted on the basis of marching cubes algorithm and Boolean operation. The accuracy of the Dental Splint can be guaranteed since the original mesh is utilized to form the result surface. Using EasySplint, the Dental Splints can be designed in about 10 minutes and saved as a stereo lithography (STL) file for 3D printing in clinical applications. Three phantom experiments were conducted and the efficiency of our method was demonstrated.
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a rapid prototype fabrication method of Dental Splint based on 3d simulation and technology
Journal of Biomedical Engineering, 2006Co-Authors: Xiaojun Chen, Shilei Zhang, Chengtao WangAbstract:: The conventional design and fabrication of the Dental Splint (in orthognathic surgery) is based on the preoperative planning and model surgery so this process is of low precision and efficiency. In order to solve the problems and be up to the trend of computer-assisted surgery, we have developed a novel method to design and fabricate the Dental Splint--computer-generated Dental Splint, which is based on three-dimensional model simulation and rapid prototype technology. After the surgical planning and simulation of 3D model, we can modify the model to be superior in chewing action (functional) and overall facial appearance (aesthetic). Then, through the Boolean operation of the Dental Splint blank and the maxillofacial bone model the model of Dental Splint is formed. At last, the Dental Splint model is fabricated through rapid prototype machine and applied in clinic. The result indicates that, with the use of this method, the surgical precision and efficiency are improved.
Astrid L Kruse - One of the best experts on this subject based on the ideXlab platform.
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evaluation of two Dental registration Splint techniques for surgical navigation in cranio maxillofacial surgery
Journal of Cranio-maxillofacial Surgery, 2014Co-Authors: Dominik Venosta, Astrid L Kruse, Heinztheo Lubbers, Klaus Wilhelm Grätz, Felix Matthews, Martin Lanzer, Thomas GanderAbstract:BACKGROUND: Surgical navigation requires precise registration of the pre-operative image dataset to the patient in the operation theatre. Different marker-based and marker-free registration techniques are available, each of them with advantages and disadvantages regarding precision and clinical handling. In this model study, the precision of two Dental Splint techniques for marker-based registration is analyzed. MATERIALS AND METHODS: A synthetic full-size human skull was registered with its cone beam computed tomography dataset using (a) a Dentally-mounted "rapid" occlusal Splint with five titanium screws directly attached to the Splint, (b) an "extender", a Dentally-mounted occlusal Splint with similar fiducials fixed to an extension of the Splint. The target registration error was measured for 170 landmarks distributed over the viscero- and neurocranium in 10 repeats per Splint type using the Vector Vision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical evaluations were performed per anatomical region. RESULTS: In the periorbital region, the rapid Splint, with an average deviation of 1.50 mm (SD = 0.439) showed greater accuracy than the extender with 1.76 mm (SD = 0.525). The viscerocranial results for both Splints were similar (extender 1.84 mm, SD = 0.559, rapid occlusal Splint 1.86 mm, SD = 0.686). In the cranial vault region, registration with the extender (2.33 mm, SD = 0.685) proved to be more precise than with the rapid Splint (2.86 mm, SD = 0.929). CONCLUSIONS: Due to the more compact dimension of the rapid occlusal Splint, errors close to the Splint were smaller compared to the extender technique. The advantage of greater distances between the registration fiducials on the extender is particularly important in areas such as the orbital roof, the cranial vault, and the lateral skull base.
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point to point registration with mandibulo maxillary Splint in open and closed jaw position evaluation of registration accuracy for computer aided surgery of the mandible
Journal of Cranio-maxillofacial Surgery, 2012Co-Authors: Cyrill Bettschart, Astrid L Kruse, Joachim A Obwegeser, Heinztheo Lubbers, Klaus Wilhelm Grätz, Wolfgang Zemann, Felix MatthewsAbstract:Abstract Introduction Computer navigation plays an increasingly important role in craniomaxillofacial surgery. The difficulties in computer navigation at the craniomaxillofacial site lie in the accurate transmission of the dataset to the operating room. This study investigates the accuracy of the Dental-Splint registration method for the skull, midface, and mandible. Material and methods A synthetic human skull model was prepared with landmarks and scanned with cone beam computer tomography (CBCT). Two registration Splints fixed the mandible against the viscerocranium in two different positions (closed vs. open). The target registration error was computed in all 278 landmarks spread over the entire skull and mandible in 10 repeated measurements using the VectorVision 2 (BrainLAB Inc., Feldkirchen, Germany) navigation system. Results If registered in the closed position an average precision of 2.07mm with a standard deviation (SD) of 0.78mm was computed for all landmarks distributed over the whole skull. Registration in the open position resulted in an average precision of 1.53mm (SD=0.55mm). For single landmarks the precision decreases linearly with distance from the reference markers. The longer the three-dimensional distance between the registration points, the more precise the computer navigation is, mainly in the most posterior area of the cranium. Conclusion Our findings in the cranium are comparable with those of other studies. Artificial fixation of the lower jaw via Splint seems to introduce no additional error. The registration points should be as far apart from each other as possible during navigation with the Splint.
Klaus Wilhelm Grätz - One of the best experts on this subject based on the ideXlab platform.
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evaluation of two Dental registration Splint techniques for surgical navigation in cranio maxillofacial surgery
Journal of Cranio-maxillofacial Surgery, 2014Co-Authors: Dominik Venosta, Astrid L Kruse, Heinztheo Lubbers, Klaus Wilhelm Grätz, Felix Matthews, Martin Lanzer, Thomas GanderAbstract:BACKGROUND: Surgical navigation requires precise registration of the pre-operative image dataset to the patient in the operation theatre. Different marker-based and marker-free registration techniques are available, each of them with advantages and disadvantages regarding precision and clinical handling. In this model study, the precision of two Dental Splint techniques for marker-based registration is analyzed. MATERIALS AND METHODS: A synthetic full-size human skull was registered with its cone beam computed tomography dataset using (a) a Dentally-mounted "rapid" occlusal Splint with five titanium screws directly attached to the Splint, (b) an "extender", a Dentally-mounted occlusal Splint with similar fiducials fixed to an extension of the Splint. The target registration error was measured for 170 landmarks distributed over the viscero- and neurocranium in 10 repeats per Splint type using the Vector Vision2 (BrainLAB AG, Heimstetten, Germany) navigation system. Statistical and graphical evaluations were performed per anatomical region. RESULTS: In the periorbital region, the rapid Splint, with an average deviation of 1.50 mm (SD = 0.439) showed greater accuracy than the extender with 1.76 mm (SD = 0.525). The viscerocranial results for both Splints were similar (extender 1.84 mm, SD = 0.559, rapid occlusal Splint 1.86 mm, SD = 0.686). In the cranial vault region, registration with the extender (2.33 mm, SD = 0.685) proved to be more precise than with the rapid Splint (2.86 mm, SD = 0.929). CONCLUSIONS: Due to the more compact dimension of the rapid occlusal Splint, errors close to the Splint were smaller compared to the extender technique. The advantage of greater distances between the registration fiducials on the extender is particularly important in areas such as the orbital roof, the cranial vault, and the lateral skull base.
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point to point registration with mandibulo maxillary Splint in open and closed jaw position evaluation of registration accuracy for computer aided surgery of the mandible
Journal of Cranio-maxillofacial Surgery, 2012Co-Authors: Cyrill Bettschart, Astrid L Kruse, Joachim A Obwegeser, Heinztheo Lubbers, Klaus Wilhelm Grätz, Wolfgang Zemann, Felix MatthewsAbstract:Abstract Introduction Computer navigation plays an increasingly important role in craniomaxillofacial surgery. The difficulties in computer navigation at the craniomaxillofacial site lie in the accurate transmission of the dataset to the operating room. This study investigates the accuracy of the Dental-Splint registration method for the skull, midface, and mandible. Material and methods A synthetic human skull model was prepared with landmarks and scanned with cone beam computer tomography (CBCT). Two registration Splints fixed the mandible against the viscerocranium in two different positions (closed vs. open). The target registration error was computed in all 278 landmarks spread over the entire skull and mandible in 10 repeated measurements using the VectorVision 2 (BrainLAB Inc., Feldkirchen, Germany) navigation system. Results If registered in the closed position an average precision of 2.07mm with a standard deviation (SD) of 0.78mm was computed for all landmarks distributed over the whole skull. Registration in the open position resulted in an average precision of 1.53mm (SD=0.55mm). For single landmarks the precision decreases linearly with distance from the reference markers. The longer the three-dimensional distance between the registration points, the more precise the computer navigation is, mainly in the most posterior area of the cranium. Conclusion Our findings in the cranium are comparable with those of other studies. Artificial fixation of the lower jaw via Splint seems to introduce no additional error. The registration points should be as far apart from each other as possible during navigation with the Splint.