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Rainer Schmelzeisen

Publications and source records attributed to Rainer Schmelzeisen.

At least 19 recordsLinked to original sources
PubMed2007

Bone formation after sinus augmentation with engineered bone.

OBJECTIVES: The aim of the following investigation was to quantify the resorption rate of tissue-engineered bone grafts in the maxillary sinus using volume measurements. MATERIAL AND METHODS: Sinus floor augmentation using autologous bone grafts from the iliac crest (n=17, group 1) was compared with commercially produced transplants of human cells seeded on polyglycolid-polylactid (PLGA) scaffolds (Oral Bone) (n=14, group 2). RESULTS: The total resorption rate for autologous transplants 3 months post operation was 29%, while the tissue-engineered bone showed a resorption rate of 90%. The autologous bone had a bone density of up to 266-551 Hounsfield units (HU), while sufficient mineralization of tissue-engineered bone was found in only one case (152 HU). CONCLUSION: In this clinical study, the use of autologous cancellous bone grafts in sinus augmentation was more reliable than scaffolds containing cultured osteoblasts. Further tissue-engineered bone transplants should be examined to draw general conclusions about the use of tissue-engineered grafts compared with autologous bone grafts for maxillary sinus augmentation.

Alveolar Ridge Augmentation↗
PubMed2007

Complicated late mandibular fracture following third molar removal.

Mandibular fractures are a rare complication after third molar removal. Symptoms show a wide variance. Treatment options range from prescription of a soft diet to surgical treatment by open reduction and internal fixation. This article describes a patient who presented a late mandibular fracture following third molar removal. The fracture was not detectable in radiographs at the time of fracture. Six weeks after the reported cracking noise, the patient presented a mandibular fracture with associated osteomyelitis. Treatment by open reduction and internal fixation and autologous iliac crest graft was performed via a submandibular approach. The delayed diagnosis of this pathologic fracture demonstrates the necessity of repeated radiologic controls to prevent osteomyelitis when a fracture is suspected.

Bone Plates↗
PubMed2006

Obturator after marsupialization of a recurrence of a radicular cyst of the mandible.

The radicular cyst is the most common odontogenic cyst. We present the case of a 51-year-old man with an extended recurrence of a radicular cyst of the mandible that was treated with marsupialization. Subsequently, an obturator was fitted, and in 10 months a resolution (clinically and radiographically) of the cystic cavity was noticed without any signs of recurrence. The marsupialization is a well-established, nonaggressive treatment of large odontogenic cysts and shows advantages in preserving vital structures, with reduced risk of pathological mandibular fractures. The patient, however, must be compliant and accept the prolonged treatment of marsupialization.

Humans↗
PubMed2006

Case report: brain and liver abscesses caused by oral infection with Streptococcus intermedius.

Organ abscesses are a rare and life-threatening complication mostly of hematogenously disseminated infections. We report a case of brain and liver abscesses. Identification of the lesions was made by contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI), respectively. An oral examination comprised an oral focus of infection. Streptococcus intermedius was isolated from oral smear, liver and ventricular drainage, and blood sample. After the commencement of antibiotic therapy, drainage of abscesses and oral rehabilitation, complete recovery was noted.

Adult↗
PubMed2006

Individual preformed titanium meshes for orbital fractures.

OBJECTIVES: The aim of this investigation was to develop and test the accuracy of a procedure for fabricating individual preformed titanium meshes for orbital fractures. STUDY DESIGN: Preoperative CT datasets from five patients with orbital fractures were used for 3D reconstruction by mirroring the unaffected side onto the defective one, resulting in a new sub-volume. A template for adaptation of the titanium mesh was produced by applying these sub-volumes. Navigation-aided procedures guaranteed the exact placement of the preformed mesh during the operation. RESULTS: The accuracy of the reconstructed orbital floor was determined to be approximately 1 mm, which lies within the technical limit of detection. CONCLUSION: These results indicate a further application or navigation-aided reconstruction, which will serve as a pilot project for further investigations. Clustered databases of patients will be used to produce various template sets, reflecting ideal skeletons, according to age, sex, and other patient variables. These could be used for manufacturing preformed osteosynthesis templates.

Databases, Factual↗
PubMed2006

Anatomical 3-dimensional pre-bent titanium implant for orbital floor fractures.

PURPOSE: This cadaver study evaluates the use of pre-bent 3-dimensional titanium mesh implants for orbital floor and medial wall reconstruction. DESIGN: Nonrandomized comparative study. PARTICIPANTS: Eight human cadaveric heads (n = 16 orbits). METHODS: Transcutaneous incisions were used to expose both orbital floors in each cadaveric head. Unilateral orbital floor and medial wall fractures were generated in each specimen. The contralateral orbit remained uninjured. The fractures then were repaired with pre-bent titanium mesh fan plates molded from aluminum templates presenting different sizes. The templates were generated from topographical computed tomography (CT) data previously obtained from normal subjects. The accuracy of orbital reconstruction was evaluated with postoperative CT scans. MAIN OUTCOME MEASURES: The mean value of the distances between the implant and the bony orbit was evaluated. RESULTS: The mean distance between all 16 plates and their respective orbital floors/medial walls was 0.81+/-0.74 mm. Mean values were 0.68+/-0.63 mm for the unfractured side and 0.93+/-0.82 mm for the fractured side. No significant differences were found between orbits when evaluated for side of injury, gender, or size of defect. CONCLUSION: Pre-bent 3-dimensional titanium mesh implants provide accurate reconstruction of orbital floor and medial orbital wall fractures. The mean implant error was <1 mm for all orbits studied.

Adult↗
PubMed2006

Computer-assisted extracorporeal orbital reconstruction after optic nerve decompression by removal of sphenoid bone.

The removal of sphenoid bone parts was performed by the admitting neurosurgeons on a patient who presented an optic nerve compression syndrome. Beside the orbital trauma, an extensive midfacial trauma was sustained with dislocated multifractures of the zygomatic complex. In a secondary procedure, the orbital cavity was reconstructed successfully using 3 different methods of computer-assisted surgery. First, the reconstruction of the zygomatic complex was controlled intraoperatively by a virtual model obtained by mirroring the unaffected side to the affected side. Second, extracorporeal bone parts were virtually preoperatively relocated and orientated. The reconstruction of the orbital cavity by the insertion of these bony fragments was performed intraoperatively as planned after the zygomatic complex reconstruction. Third, the virtual reconstruction of the orbital floor was performed using preoperatively individually bent and preformed orbital titanium mesh. Combinations of these methods demonstrate the practical and high value of computer-assisted surgery in complex reconstructive craniofacial surgery.

Adult↗
PubMed2006

Clinical application of tissue-engineered transplants. Part I: mucosa.

OBJECTIVES: The study series aims at testing the feasibility of the clinical application of tissue-engineered oral mucosa. The preliminary results were gathered over a period varying from 6 months to 12 years depending on the surgical method. METHODS: Tissue-engineered oral mucosa was used to cover defects in various surgical procedures like vestibuloplasty (n=42), freeing of the tongue (n=10), prelaminating the radial flap (n=5) and reconstruction of the urethra (n=16). In all interventions small samples of oral mucosa were harvested, cut into small pieces, resuspended in culture medium and seeded into a culture flask. Cultured keratinocytes were transferred onto membranes which then were used to cover mucosal defects in the oral cavity. RESULTS: To gain a graft of 15 cm(2) size a mucosa biopsy of 4-8 mm(2) and 40 ml autologous patients serum is needed. Tissue-engineered oral mucosa was applied successfully in all four surgical methods. Six months after transplantation a regular epithelial layering with a histological delimitation of the stratum, epithelial crest and a strong basal membrane appeared. According to the reception site the tissue engineered oral mucosa differentiated in several ways. CONCLUSION: Tissue-engineered oral mucosa fulfils the requirements for clinical routine. With view to healing time and outcome it does not appear to be superior to regular harvested oral mucosa transplants. Because of a smaller harvesting defect and primary wound closure at the actual operation site the patients' convenience is increased. Thus this method reduces morbidity and advances the quality of life.

Aged↗
PubMed2005

Computer-assisted reconstruction of orbital floor based on cone beam tomography.

We used a navigation system for computer-assisted preoperative planning based on cone beam tomography with virtual reconstruction to obtain symmetry of the orbit and intraoperative control of virtual contours. In operations for reconstruction of the orbital floor this technique offers a reliable intraoperative control in an area of limited exposure and visibility. There was no significant difference in visualisation of anatomical structures between the cone beam tomographic digital imaging and communication (DICOM) data and computed tomographic data. Cone beam tomography seems to be suitable for computer-assisted planning in the management of orbital trauma with reduced costs and less radiation.

Aged↗
PubMed2005

Navigational maxillofacial surgery using virtual models.

Ablative tumor surgery and orbital and midface reconstruction, as much as orthognathic surgery, requires detailed planning using computed tomography (CT) or magnetic resonance imaging (MRI). These techniques also allow simulation of complex surgeries preoperatively. Proper reconstruction depends on reliable information to choose the correct type of grafts and to predict the outcome. This study evaluates the benefit and indications of computer-assisted surgery in the treatment of 107 patients who underwent craniomaxillofacial surgery. Based on a CT or MRI data set, an optical navigation system was used for preoperative planning, intraoperative navigation, and postoperative control. Surgery could be preoperatively planned and intraoperatively navigated. Preoperatively, it required that soft and hard tissues were measured using the mirrored data set of the unaffected side; the size and location of the graft were chosen virtually. Intraoperatively contours of transplanted tissues were navigated to the preoperatively simulated reconstructive result. Computer-assisted treatment was successfully completed in all 107 cases. Preoperatively outlined safety margins could be exactly controlled during tumor resection. Reconstruction was designed and performed precisely as virtually planned. Image-guided treatment improves preoperative planning by visualizing the individual anatomy, outlining the intended reconstructive outcome, and by objectifying the effect of adjuvant therapy. Intraoperative navigation makes tumor and reconstructive surgery more reliable by showing the safety margins, saving vital structures, and leading the reconstruction to preoperatively planned objectives.

Adolescent↗
PubMed2005

Anterior approach to implant the Jarvik 2000 with retroauricular power supply.

The retroauricular power supply of the Jarvik 2000 (Jarvik Heart Inc, New York, NY) left ventricular assist device is suitable for permanent support, as it is associated with fewer infections than conventional drivelines. Implantation through a left-lateral thoracotomy limits the performance of additional cardiac procedures. We describe a technique that used a sternotomy for the implantation of the Jarvik 2000 with retroauricular power supply in two patients. The retroauricular power supply of the Jarvik 2000 can be provided with an anterior approach, allowing full surgical access to the heart. If the outflow graft to the ascending aorta indeed reduces aortic stasis and thromboembolic events, the anterior approach with retroauricular power delivery might evolve into a standard procedure.

Aged↗
PubMed2005

Implantation of the Jarvik 2000 left-ventricular-assist-device: role of the maxillofacial surgeon.

The Jarvik 2000 system of axial-flow LVAD-is implanted for permanent mechanical circularly support in patients with end-stage heart failure waiting to undergo heart transplantation. The battery is connected with a power plug to the percutaneous skull-mounted footplate, which is monocortically fixated to the retro auricular bone. Patient selection should be highly specific, including careful preoperative evaluation. No device failures have been published so far, but complications can occur due to heparinisation. We describe the procedure from the perspective of the maxillofacial surgeon and give suggestions to prevent surgical complications.

Cardiac Output, Low↗
PubMed2005

Five-year experience with the transoral endoscopically assisted treatment of displaced condylar mandible fractures.

BACKGROUND: From April of 1998 to May of 2003, the minimally invasive transoral approach for endoscopically assisted reduction and osteosynthesis of 62 displaced condylar mandible fractures was performed in 58 patients. METHODS: By means of limited transoral incision, the endoscopically assisted reduction and fixation of condylar fractures was performed using 30- and 45-degree angled endoscopes. Twenty-five fractures were condylar and 37 were subcondylar. The condylar neck of the proximal fragment was displaced medially in 17 fractures and laterally in 45 fractures. Four patients presented bilateral condylar mandible fractures. Using angled endoscopes, good visibility of the fracture site was obtained, which allowed for precise anatomical reduction in all patients. An angulated drill and screwdriver facilitated miniplate fixation by means of the transoral approach. The mean operating time was measured in the last 30 consecutive cases: 1 hour 5 minutes. RESULTS: Postoperatively, all patients showed quick recovery to preinjury occlusion. Normal temporomandibular joint function was noted 6 months after surgery in all patients. CONCLUSIONS: The transoral endoscopically assisted treatment using an angulated drill and screwdriver is the method of choice for surgical management of displaced condylar fractures, even in fractures with medial override. Facial nerve injury and visible scars are avoided by using the transoral approach.

Adult↗
PubMed2005

[Augmentation of alveolar ridge defects: autologous bone transplant from the zygomatic alveolar crest--a new technique].

The insertion of dental implants with simultaneous loss of alveolar bone still represents a challenge. A traumatical tooth loss within the range of the front of the maxillary is frequently connected with a clear substance defect. The goal of a pre-implantologically treatment must be therefore the hard tissue reconstruction of the defect. Thus the implant camp is optimized and the prosthetical necessary implant position is guaranteed. In this case report the reconstruction of a vertical and horizontal bone loss with a transplant from the Crista zygomatico alveolaris is represented. The withdrawal of the bone transplant took place under indulgence of the vestibular membrane of the maxillary sinus by means of piezosurgery. After an appropriate healing time the single tooth gap was supplied with an ITI implant of the company Straumann (Freiburg, Germany).

Alveolar Bone Loss↗
PubMed2004

Navigation-aided reconstruction of medial orbital wall and floor contour in cranio-maxillofacial reconstruction.

The reconstruction of the anterio-posterior inclination of the medial aspect of the orbital floor, despite a wide 360 degrees exposure, including coronal and conjunctival incisions, is a challenging task in severe injuries of the orbit with massive comminution and complete displacement of the medial orbital wall and orbital floor. Out of a total of 20 patients with orbital fractures, five underwent a surgical intervention of repositioning the medial aspect of the orbital floor and especially the transition area between the orbital floor and medial orbital wall, using navigation-aided procedures. Using the mirroring tool of the Stryker-Leibinger STN-system, post-operative CTs indicated an average difference of the globe position of -4.9% between the operated side and the unaffected side, depending on the position of the medial aspect of the orbital floor. Navigation-aided procedures proved to be an essential precondition for achieving precise and predictable results in orbital reconstruction. In such cases, unlike those with an intact medial orbital wall remnant as a surgical target, bone grafts for reconstruction of the orbital floor cannot be implanted as onlay grafts.

Adult↗