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W Zechner

Publications and source records attributed to W Zechner.

10 recordsLinked to original sources
PubMed2001

Multidimensional osteodistraction for correction of implant malposition in edentulous segments.

This study examined multidimensional osteodistraction as a treatment method for correction of implant malposition and as an alternative to augmentation procedures. The prosthetically unfavourable implant positions were due to growth-related implant malposition (in the context of treatment of young patients with oligodontia) or primary bone-driven implant insertions. The radiographical and clinical findings obtained with this osteodistraction technique are presented and discussed. A tooth-supported osteodistractor for multidimensional distraction with custom-fabricated distraction abutments was used for treatment of 8 patients with a total of 9 maxillary and mandibular edentulous segments including single-tooth gaps. All patients underwent an osteotomy at a minimum distance of 1 mm from the implant surface. Following primary wound healing, distraction was carried out by 1 mm in vertical direction and 0.5 mm in the demanded transverse direction daily until the prosthetically optimized position was achieved. During and after the 12-week retention phase, the patients were evaluated clinically and radiographically. Multidimensional osteodistraction was carried out successfully in all 8 patients. The distraction distances were 3 to 11 mm in vertical direction and a maximum of 5 mm in buccolingual/buccopalatal direction. The malpositioned implants were brought into a prosthetically optimized position in all cases. The results of this study show that this multidimensional osteodistraction technique allows both augmentation of edentulous segments with a clearly compromised implant host site and correction of unfavourable implant positions.

Adolescent↗
PubMed1991

Injuries to the cervical spine causing vertebral artery trauma: case reports.

In four patients with lesions of the vertebral artery resulting from cervical spine injury, two were due to unilateral facet dislocation and two to fractures of the dens. There was one arterial occlusion with minor vertebrobasilar symptoms, and an arterial lesion with thrombosis causing embolic occlusion of the basilar artery with lethal outcome. In one patient a fresh fracture of the dens caused dislocation of C1/2 with reversible occlusion of the left and stenosis of the right vertebral artery, resulting in unconsciousness. In a patient with pseudarthrosis of the dens an aneurysm of the vertebral artery could be detected. Cerebellar or cerebral symptoms associated with cervical spine injury should be investigated by vertebral angiography because vertebral arterial injury may be more common than suspected and may simulate traumatic brain damage.

Adult↗
PubMed1991

[Computerized tomography after surgical management of scaphoid fractures and pseudarthroses with implants in place. Method and results in 15 cases].

Fifteen patients having undergone open reduction and internal fixation for scaphoid fractures were later examined by computer tomography. Herbert-screws were used in nine cases and Ender-plates in four. In two cases, Ender-plates replaced a small fragment AO-screw as well as one Herbert-screw. Computer tomography of the wrist is not indicated on a routine basis, but whenever standard X-rays are unable to determine whether surgically treated fractures have healed or nonunion has been established. Patient cooperation is of utmost importance, if artifacts due to patient movement are to be avoided. To minimize implant artifacts, axial and radio-ulnar sections are employed; palmar-dorsal sections are advantageous whenever Ender-plates are involved.

Adolescent↗
PubMed1990

[Results of magnetic resonance and computerized tomography studies of augmentation plastic surgery of the anterior cruciate ligament using carbon fibers. II].

19 patients out of those described in part I were examined by MRI and CT. We quote MRI as an excellent new mean of imaging without exposure to ionising radiation which renders sufficient information about the internal knee-structures without surgical invasion. The signal density for the neoligament as well intraarticular as in the "over the top"-position gives evidence for the ingrowth of mesenchymal structures. The MRI diagnosis was proved by histological examination in 2 cases. Very good correspondence between clinic examination and the CT-images could be found. On top of that the tibial drilling holes could be shown in an excellent way. The CT-scan is a fine instrument to judge the postoperative state of the anterior cruciate ligament. The density measurement inside and outside the bone gives evidence for mesenchymal growth inside the carbon fibre structure and the existence of a new natural ligament.

Anterior Cruciate Ligament↗
PubMed1985

[Improvement of suture technic in flexor tendon injuries. Clinical and experimental study].

Multiple causes for the rupture of sutured tendons have been reported. At the time of exploration, loosening of the knot and breakage of the suture have been found to explain failure. A knot with four throws is frequently mentioned in various series as the smallest secure knot which can be made when employing a braided polyester suture material. Experiments have shown that the distance between the ends of the tendons affects the healing process and the tensile strength of the injured tendons. In order to avoid increasing the gap between the sutured ends of the tendons with the thick knot, it can be placed away from the cut surface of the tendons and displaced into the proximal or distal end of the tendons with a small additional incision. Through a longitudinal incision, the suture is easily passed in a criss cross fashion through the tendon and the knot can be buried in the tendon. This technique assures a very delicate and exact coaptation of the tendon ends. Almost 100% of the tendons remain intact during the healing phase. According to this experience, the risk of tendon rupture is reduced as a result of an increase in the tensile strength of the suture and the displacement of the knot away from the cut surface of the tendon.

Finger Injuries↗
PubMed1977

[Problems of vascular injuries at a large industrial-accident hospital (19 year experiences at the industrial-accident hospital Vienna XII)].

This report covers 213 vessel injuries out of 840 000 injuries through accident. Even considering that these are mostly cases of polytrauma, the results could be improved significantly. This however, only under the condition that all traumatologists and surgeons active in traumatology receive practical training in vessel surgery.

Accidents, Occupational↗
PubMed1970

[Not Available].

Explore the source record for details and available documents.

Austria↗
PubMedDate not supplied

A distraction abutment system for 3-dimensional distraction osteogenesis of the alveolar process: technical note.

To date, distraction osteogenesis has been carried out exclusively with devices that allow distraction in one given direction only. However, the new distraction abutment system described in this article allows distraction in any functionally or esthetically desired direction following osseointegration of 1 or several implants, provided that there are adjacent teeth or other osseointegrated implants. With this abutment system, an implant fixed in a position dictated by available bone volume can be moved into a prosthetically desirable position following segmental osteotomy. Accordingly, it also allows correction of the position of implants that were placed at an early age but whose position has changed as the result of jaw growth. Compared with conventional augmentation techniques carried out before or after implant placement, this method should lead not only to a shorter overall treatment time, but also to reduced strain on the patient and better long-term prognosis for success of implants.

Adolescent↗
PubMedDate not supplied

Microvascular anastomosis by invagination: an experimental study.

A technique of end anastomosis of microvessels of equal or unequal diameter, requiring only two sutures is described. In the present investigation we used the common carotid artery and the femoral vein of 37 white rats. The adventitia of the proximal part of the anastomosed artery was subsequently prepared and removed. However, in case of vein anastomosis, the adventitia of the distal part was removed. Following this washing with saline solution was done. 10-0 Nylon monofil sutures, were used which were placed at 180 degrees. The anastomosis was completed by ligation in such a way that one end was invaginated into the other and was fixed firmly. Five months later the anastomoses were examined after careful preparation under the surgical microscope and photographed. A SEM examination was then done in half of them and photos were taken at 24X, 80X, 1,200x magnification. The remaining tissue was examined histologically. The findings after surgical microscope SEM and histological examination are described.

Animals↗