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En los ultimos veinte anos el tratamiento con implantes dentales ha experimentado grandes cambios. Este articulo explica que tratamientos con implantes son basicos y pueden ser realizados en una consulta dental general por un odontologo... more
En los ultimos veinte anos el tratamiento con implantes dentales ha experimentado grandes cambios. Este articulo explica que tratamientos con implantes son basicos y pueden ser realizados en una consulta dental general por un odontologo con formacion en implantologia y cuales deben realizarse en colaboracion con un implantologo.
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OBJECTIVE The aim of this study was to compare the accuracy of flat-panel volume computed tomography (fpVCT) to histopathologic evaluation of excised tumors of the jaws in the detection of the degree of tumor infiltration, the presence of... more
OBJECTIVE The aim of this study was to compare the accuracy of flat-panel volume computed tomography (fpVCT) to histopathologic evaluation of excised tumors of the jaws in the detection of the degree of tumor infiltration, the presence of tumor at the resection margins, and the sizes of lesions. STUDY DESIGN This preliminary study included 47 patients undergoing jaw resection for tumor invasion of bone. The specimens were examined by histology and 3-dimensional fpVCT, and the parameters of bone infiltration, resection margins, and tumor size were determined. RESULTS In 95.7% of cases, the fpVCT results of tumorous bone infiltration were in accordance with the histologic findings. An examination of the resection margins showed 100% concordance between the 2 methods, and all resection margins were found to be clear in both fpVCT and the histologic examination. Identical pathologic and nonpathologic results were seen with the use of both diagnostic methods. Radiologic estimates of tumor size were larger than histologic measurements in the case of small tumors but the true sizes of the larger lesions were underestimated. CONCLUSIONS The intraoperative diagnostic gap can be closed by using fpVCT to investigate bone destruction, allowing one-step resections and reconstructions to become more reliable.
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Abstract This part of the book focuses on computer-aided maxillofacial surgery in the clinical practice and is written by the contributing authors of this chapter Juergen Wallner (j.wallner@medunigraz.at), Michael Schwaiger, Wolfgang... more
Abstract This part of the book focuses on computer-aided maxillofacial surgery in the clinical practice and is written by the contributing authors of this chapter Juergen Wallner (j.wallner@medunigraz.at), Michael Schwaiger, Wolfgang Zemann (Graz, Austria), and Philipp Streckbein (Giesen, Germany). The content of the chapter is based on the clinical experience of the authors and on the present literature. Today, computer-aided procedures and technologies in oral and maxillofacial surgery are mainly used for a patient-specific approach, which means that these technologies are used to try to create a personal medical surgical treatment individually for each patient. In that context, the main computer-aided patient-specific approaches are (1) image-based virtual 3D surgical planning and 3D visualization (based on digital image scan files and algorithmic segmentation), (2) 3D printed models (polymer made based on digital image scan files by the support of 3D printers in-house or by the industry partner), (3) virtual planning and manufacturing of surgical cutting guides and splints (image scan based titanium or polymer made), and (4) virtual planning and manufacturing of patient-specific implants (titanium made). This chapter gives an outline of some currently common and routinely used computer-aided procedures and technologies in clinical oral and maxillofacial surgery and includes the connected basic and surrounding information, limitations, involved research topics, and future perspectives. The following subchapters are mainly referred to procedures that are common and relevant in Austria and Germany. Differences to other European countries may exist out of organization and/or financial reasons.
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The prototype flat-panel volumetric computed tomograph (fpvCT) provides a new 3D imaging technology with detailed high resolution by using large-area flat-panel X-ray detectors. The object of this study was to evaluate the benefit of high... more
The prototype flat-panel volumetric computed tomograph (fpvCT) provides a new 3D imaging technology with detailed high resolution by using large-area flat-panel X-ray detectors. The object of this study was to evaluate the benefit of high resolution imaging using the experimental fpvCT to visualise different types of human craniofacial bone pathology. The study proved the feasibility of performing an intraoperative evaluation of free margins in bone malignancies using fpvCT. In this study, 35 bone specimens of various pathological types were examined by fpvCT. fpvCT data were compared with pre-operative multislice clinical CT images as well as with post-operative histological findings. Bone tumours can be visualised with their specific pathological architecture and infiltration structure faster and more precisely by fpvCT than by multislice CT. The analysis of the resection margins supports the surgical procedure intraoperatively, especially when an immediate reconstruction with bone transplantation is carried out. The fpvCT has a superior image quality when compared with clinical CT systems. The imaging of the bone structure itself has been shown to be useful for the interpretation of osseous resection borders. Furthermore, it can facilitate the diagnosis of tumour progression, especially in areas that are difficult to access, such as the base of the skull.
Research Interests: Dentistry, Radiology, Computed Tomography, Medicine, Humans, and 10 more3-D Imaging, Skull, Three Dimensional Imaging, Clinical Sciences, Oral Squamous Cell Carcinoma (OSCC), ORAL AND CRANIO-MAXILLOFACIAL PLASTIC SURGERY, Craniofacial, X ray Computed Tomography, Intraoperative Neurophysiological Monitoring, and Head and neck neoplasms
As stated in the first part of this publication standardized clinical photographs are essential for planning, documentation and demonstration of surgical procedures in cranio-maxillo-facial surgery (Ettorre et al., 2006). This article... more
As stated in the first part of this publication standardized clinical photographs are essential for planning, documentation and demonstration of surgical procedures in cranio-maxillo-facial surgery (Ettorre et al., 2006). This article expands the previously defined standards in facial digital photography. Additional picture sets for special topics are introduced and some common mistakes are discussed. Guidance for the prevention of pitfalls is provided and the photographic principles are reviewed. Finally the authors give recommendations for dealing with structured data storage and protection of medical photographs. The use of asset management systems such as Cumulus and Portfolio is introduced and recommended.
Research Interests: Dentistry, Photography, Digital Photography, Documentation, Facial Paralysis, and 15 moreCleft Palate, Computer Security, Medicine, Humans, Child, Europe, Malocclusion, Infant, Clinical Sciences, Information Storage and Retrieval, Adult, Medical Error, Cleft Lip, Oral Surgical Procedures, and Child preschool
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Research Interests: Immunology, Quality Improvement, Adolescent, Medicine, Quality Control, and 15 moreGermany, Humans, Orthognathic surgery, Donation, Female, Male, Clinical Sciences, Middle Aged, Adult, Retrospective Studies, Body Weight, Blood Transfusion, Blood Donors, Hematocrit, and Cardiovascular medicine and haematology
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1. Rootman J, White VA, Conners JM, Gascoyne RD. Lymphoproliferative, leukemic, and histiocytic lesions of the orbit. In: Rootman J, ed. Diseases of The Orbit, 2nd edn. Philadelphia, PA: Lippincott Williams & Wilkins, 2003; 385–416.... more
1. Rootman J, White VA, Conners JM, Gascoyne RD. Lymphoproliferative, leukemic, and histiocytic lesions of the orbit. In: Rootman J, ed. Diseases of The Orbit, 2nd edn. Philadelphia, PA: Lippincott Williams & Wilkins, 2003; 385–416. 2. Baehring JM, Damek D, Martin EC et al. Neurolymphomatosis. Neurooncol 2003; 5: 104–15. 3. Siqueira GB, Jain A, Fernando C, Cruz AAV. Bilateral infraorbital nerve involvement in idiopathic orbital myositis. Ophthal Plast Reconstr Surg 2002; 18: 474–8. 4. Jakobiec FA, Knowles DM. An overview of ocular adnexal lymphoid tumors. Trans Am Ophthalmol Soc 1989; 87: 420–42; discussion 42–4. 5. Lowen MS, Saraiva VS, Martins MC, Burnier MN Jr. Immunohistochemical profile of lymphoid lesions of the orbit. Can J Ophthalmol 2005; 40: 634–9.
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ObjectiveTo photogrammetrically objectify changes in nonsynostotic craniofacial deformity in orthotically treated versus untreated infants.DesignA statistical retrospective pairwise comparison of two respective three-dimensional (3D)... more
ObjectiveTo photogrammetrically objectify changes in nonsynostotic craniofacial deformity in orthotically treated versus untreated infants.DesignA statistical retrospective pairwise comparison of two respective three-dimensional (3D) photo scans of 80 children performed in a 6-month time lag.PatientsTwo comparable samples of children (40 treated, 40 untreated) with nonsynostotic cranial deformity.InterventionsRespective 3D photo scans were matched using Cranioform Analytics 4.0 software.Main Outcome MeasuresMedian change of 30° Cranial Vault Asymmetry Index (CVAI), modified CVAI (CVAImod), Cranial Index (CI), and posterior symmetry ratio (PSR).ResultsWe found an improvement in Δ30° CVAI by 3.3% (treated) and by 1.31% (untreated), respectively. CVAImodimproved by 3.46% in the treated group and by 1.55% in the untreated group. CI improved by 4.41% in the treated group and by 3.68% in the untreated group, and PSR improved by 0.71 in the treated group and 0.49 in the untreated group. Al...
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A patient presents with a keratocystic odontogenic tumour of the left maxillary sinus. In computed tomography scans, extensive pressure-induced osseous atrophy of the sinus walls is detected. Endoscopic cystectomy of the tumour was... more
A patient presents with a keratocystic odontogenic tumour of the left maxillary sinus. In computed tomography scans, extensive pressure-induced osseous atrophy of the sinus walls is detected. Endoscopic cystectomy of the tumour was performed, with subsequent clinical follow-up. A second computed tomography scan revealed almost complete regeneration of the sinus walls. Where spontaneous regeneration of osseous structures is possible, restraint should be exercised when assessing indications for bony reconstruction during initial conservative surgery such as enucleation.
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Micro-gaps and osseous overload in the implant-abutment connection are the most common causes of peri-implant bone resorption and implant failure. These undesirable events can be visualized on standardized three-dimensional finite element... more
Micro-gaps and osseous overload in the implant-abutment connection are the most common causes of peri-implant bone resorption and implant failure. These undesirable events can be visualized on standardized three-dimensional finite element models and by radiographic methods. The present study investigated the influence of 7 available implant systems (Ankylos, Astra, Bego, Brånemark, Camlog, Straumann, and Xive) with different implant-abutment connections on bone overload and the appearance of micro-gaps in vitro. The individual geometries of the implants were transferred to three-dimensional finite element models. In a non-linear analysis considering the pre-loading of the occlusion screw, friction between the implant and abutment, the influence of the cone angle on bone strain, and the appearance of micro-gaps were determined. Increased bone strains were correlated with small (< 15°) cone angles. Conical implant-abutment connections efficiently avoided micro-gaps but had a negati...
Research Interests: Materials Science, Dentistry, Nonlinear dynamics, Dental Implants, Medicine, and 11 moreFinite Element Analysis, Humans, Computer Simulation, Three Dimensional Imaging, Dental, Implant, Dental Implant-Abutment Design, Dental Implant, Abutments and Dental Implants, Biomechanical Phenomena, and Abutment
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BackgroundVirtual surgical planning (VSP) for jaw reconstruction with free fibula flap (FFF) became a routine procedure and requires computed tomography angiography (CTA) for preoperative evaluation of the lower limbs vascular system and... more
BackgroundVirtual surgical planning (VSP) for jaw reconstruction with free fibula flap (FFF) became a routine procedure and requires computed tomography angiography (CTA) for preoperative evaluation of the lower limbs vascular system and the bone. The aim of the study was to assess whether the distribution and density of periosteal branches (PB) and septo-cutaneous perforators (SCP) of the fibular artery have an impact on flap success.MethodThis retrospective clinical study assessed preoperative CTA of the infra-popliteal vasculature and the small vessel system of 72 patients who underwent FFF surgery. Surgical outcome of flap transfer includes wound healing, subtotal, and total flap loss were matched with the segmental vascular supply.ResultA total of 72 patients (28 females, 38.9 %; 44 males, 61.1 %) fulfilled the study inclusion criteria. The mean age was 58.5 (± 15.3 years). Stenoses of the lower limbs’ vessel (n = 14) were mostly detected in the fibular artery (n = 11). Flap su...
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The aim of this monocentric, retrospective clinical study was to evaluate the status of osseous union in uni- and poly-segmental mandible reconstructions regarding conventional angle-stable manually bent osteosynthesis plates (Unilock 2.0... more
The aim of this monocentric, retrospective clinical study was to evaluate the status of osseous union in uni- and poly-segmental mandible reconstructions regarding conventional angle-stable manually bent osteosynthesis plates (Unilock 2.0 mm) versus titan laser-melted PSI patient-specific implant’s (PSI). The clinical impact of PSI’s high stiffness fixation methods on bone healing and regeneration is still not well addressed. The special interest was in evaluating the ossification of junctions between mandible and fibula and between osteotomized fibula free flap (FFF) segments. Panoramic radiograph (OPT), computed tomography (CT) scans, or cone-beam CTs (CBCT) of patients who underwent successful FFF for mandible reconstruction from January 2005 to December 2020 were analyzed. A total number of 89 cases (28 females (31.5%), 61 males (68.5%), mean age 58.2 ± 11.3 years, range: 22.8–82.7 years) fulfilled the chosen inclusion criteria for analysis (conventional: n = 44 vs. PSI: n = 45)...
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Einleitung: Bei obstruktiven Sialadenitiden ist die DVT-Sialographie ein innovatives Verfahren zur Speichelgangdiagnostik. In der retrospektiven Arbeit wurde untersucht, wie sich die Ergebnisse der DVT-Sialographie auf die... more
Einleitung: Bei obstruktiven Sialadenitiden ist die DVT-Sialographie ein innovatives Verfahren zur Speichelgangdiagnostik. In der retrospektiven Arbeit wurde untersucht, wie sich die Ergebnisse der DVT-Sialographie auf die Therapiestrategie auswirkten. Material und Methoden: Die Indikation zur DVT-Sialographien[zum vollständigen Text gelangen Sie über die oben angegebene URL]
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This part of the book focuses on computer-aided maxillofacial surgery in the clinical practice and is written by the contributing authors of this chapter Juergen Wallner (j.wallner@medunigraz.at), Michael Schwaiger, Wolfgang Zemann (Graz,... more
This part of the book focuses on computer-aided maxillofacial surgery in the clinical practice and is written by the contributing authors of this chapter Juergen Wallner (j.wallner@medunigraz.at), Michael Schwaiger, Wolfgang Zemann (Graz, Austria), and Philipp Streckbein (Giesen, Germany). The content of the chapter is based on the clinical experience of the authors and on the present literature. Today, computer-aided procedures and technologies in oral and maxillofacial surgery are mainly used for a patient-specific approach, which means that these technologies are used to try to create a personal medical surgical treatment individually for each patient. In that context, the main computer-aided patient-specific approaches are (1) image-based virtual 3D surgical planning and 3D visualization (based on digital image scan files and algorithmic segmentation), (2) 3D printed models (polymer made based on digital image scan files by the support of 3D printers in-house or by the industry ...
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An important challenge in the field of dental and orthopedic implantology is the preparation of implant coatings with bioactive functions that feature a high mechanical stability and at the same time mimic structural and compositional... more
An important challenge in the field of dental and orthopedic implantology is the preparation of implant coatings with bioactive functions that feature a high mechanical stability and at the same time mimic structural and compositional properties of native bone for a better bone ingrowth. This study investigates the influence of magnesium addition to zirconia-calcium phosphate coatings. The mixed coatings were prepared with varying additions of either magnesium oxide or magnesium fluoride to yttria-stabilized zirconia and hydroxyapatite. The coatings were deposited on zirconia discs and screw implants by wet powder spraying. Microstructure studies confirm a porous coating with similar roughness and firm adhesion not hampered by the coating composition. The coating morphology, mechanical flexural strength and calcium dissolution showed a magnesium content-dependent effect. Moreover, the in vitro results obtained with human osteoblasts reveal an improved biological performance caused b...
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Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia... more
Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants.
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The release of active molecules or the control of nosocomial infections for improved osteoinduction is ideally addressed by a bone substitute material. For this purpose, the feasibility of a mild one-pot process is probed for... more
The release of active molecules or the control of nosocomial infections for improved osteoinduction is ideally addressed by a bone substitute material. For this purpose, the feasibility of a mild one-pot process is probed for incorporating directly active proteins and antibiotics in a hydroxyapatite (HAp) based scaffold. The effect of two serum model proteins, bovine serum albumin (BSA) and fibrinogen (FIB), on the microstructure, on selected mechanical properties as well as on degradation behaviour and on protein release are investigated. By protein incorporation, the porosity can be adjusted between 54 and 70% especially due to the foaming ability of BSA. The addition of 5 wt% FIB doubles the biaxial flexural strength up to 6 MPa in comparison to samples without proteins (3 MPa). Protein release experiments show that a rapid release takes place within the first days (between around 3% for FIB and 38% for BSA). As a possible application for osteomyelitis treatment, vancomycin and g...
Research Interests: Materials Science, Biomedical Engineering, Microstructure, Medicine, Fibrinogen, and 15 moreDiffusion, Biomedical Materials, Medical Biotechnology, Animals, Drug Delivery Systems, Cattle, Biomolecule, Agar, Bovine Serum Albumin, Bone Substitutes, Materials Testing, Durapatite, Biocompatible Materials, Bone and Bones, and Gentamicins
Research Interests: Orthodontics, Photogrammetry, Photography, Medicine, Cephalometry, and 15 moreHumans, Female, Feasibility Studies, Male, Infant, Forehead, Parietal Bone, Clinical Sciences, Age Factors, Fracture Frontal Bone, Craniofacial Surgery, Orthotic Devices, Deformity, Brachycephaly, and Craniofacial Abnormalities
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Necrotizing fasciitis of the head and neck is a rare, very severe disease, which, in most cases, originates from odontogenic infections and frequently ends with the death of the patient. Rapid surgical intervention in combination with a... more
Necrotizing fasciitis of the head and neck is a rare, very severe disease, which, in most cases, originates from odontogenic infections and frequently ends with the death of the patient. Rapid surgical intervention in combination with a preferably pathogen-specific antibiotic therapy can ensure patients’ survival. The question arises concerning which pathogens are causative for the necrotizing course of odontogenic inflammations. Experimental 16S-rRNA gene analysis with next-generation sequencing and bioinformatics was used to identify the microbiome of patients treated with an odontogenic necrotizing infection and compared to the result of the routine culture. Three of four patients survived the severe infection, and one patient died due to septic multiorgan failure. Microbiome determination revealed findings comparable to typical odontogenic abscesses. A specific pathogen which could be causative for the necrotizing course could not be identified. Early diagnosis and rapid surgica...
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In 1998, a modification of the macrostructure of the Frialit-2 implant in the cervical region was introduced to stabilize peri-implant bone. Limited data are available on the clinical effect of this modification. Therefore, the... more
In 1998, a modification of the macrostructure of the Frialit-2 implant in the cervical region was introduced to stabilize peri-implant bone. Limited data are available on the clinical effect of this modification. Therefore, the soft-tissue situation, marginal bone loss, and implant failure rate were analyzed after 4 years of clinical experience with the modified Frialit-2 Synchro implant. From 1998 to 2001, 190 cervically modified implants were placed and documented prospectively in 58 patients. Of these implants, 147 were placed in original jaw bone, 22 in areas augmented with local osteoplasty, and 21 in iliac crest bone graft. The main indications for implantation were an atrophic edentulous alveolar crest (n = 99) and support for a partial denture (n = 39), followed by restoration of a shortened dental arch (n = 28) and single tooth replacement (n = 24). In a special clinical examination, 39 patients with 134 implants were investigated. The average in situ time of the 134 implan...