Long-term skeletal and dental stability after orthognathic surgery of the maxillo-mandibular complex in Class II patients with transverse discrepancies.

Introduction: Two-jaw surgery has become the standard procedure for correcting skeletal maxillo-mandibular discrepancies in adults. However, only a few studies have reported on the long-term stability of bimaxillary orthognathic surgery in patients with Class II malocclusion and transverse discrepancies. In this study, the long-term outcome of two-piece maxillary treatment during bimaxillary surgery in patients with skeletal Class II malocclusion was examined and the results are discussed.

A new technique for sandwich osteoplasty with interpositional bone grafts for fixation.

Purpose: To present a new technique for sandwich osteoplasty in the posterior mandible and to evaluate its feasibility as part of dental implant treatment.

Materials And Methods: A retrospective study of sandwich osteoplasty in the posterior mandible was conducted. No osteosynthetic material was used to stabilize the osteotomy.

Intramandibular course of the mandibular nerve; clinical significance for distraction and implantology.

Objective: Loss of teeth is accompanied with loss of function and therefore reduction of alveolar bone height. Insufficient bone height can jeopardize the anchorage of implants or surgical procedures such as distraction osteogenesis, because of possible mandibular nerve damage. The goal of this investigation was to determine the exact course of the intramandibular nerve in edentulous mandibles.

The use of intra-osseous versus extra-osseous distraction devices in atrophic mandibles.

To allow for implant placement in severe atrophic edentulous mandibles, distraction osteogenesis can be used to gain sufficient bone height. The efficacy of extra-osseous and intra-osseous devices is evaluated. In this retrospective study, 45 patients treated with an extra-osseous device (EOD) were compared with 43 patients treated with an intra-osseous device (IOD).

Altered position of the medial lingual nutritional foramina at different stages of alveolar ridge atrophy.

To determine the altered location of the medial lingual nutritional foramina in different stages of bone resorption, 55 cadaveric mandibles were selected for this study from a total of 1532. Prevalence, location of the foramen (lingual, cranial, labial), application of Atwood classification (grades 1-6), and macroanatomic dissections were tools of this examination. An increasing grade of atrophy leads to a shift in position of the medial lingual nutritional foramen.

Hemorrhage secondary to interforaminal implant surgery: anatomical considerations and report of a case.

Understanding the anatomy of the floor of mouth is very important as severe submandibular hemorrhages are life threatening. This case report illustrates the potential hemorrhage consequences of implant surgery within the interforaminal region. The highly vascularized interforaminal region is susceptible to hemorrhage, which can be induced simply by instruments causing vascular trauma.

Simultaneous maxillary sinus lifting and implant placement with autogenous parietal bone graft: outcome of 17 cases.

The aim of this study was to retrospectively evaluate the surgical technique of sinus floor elevation with autogenous parietal bone grafting in conjunction with immediate dental implants for the reconstruction of the maxilla in deficient maxillary alveolar ridges. Seventeen patients who underwent sinus floor elevation with bone graft from the parietal bone between 2005 and 2007 were included in the study. Cases of extremely deficient bone level in the alveolar ridge<4mm were included in the study.

3D-FEM and histomorphology of mandibular reconstruction with the titanium functionally dynamic bridging plate.

Biomechanical investigation of the mandible is difficult due to the complex geometrical structure. A three-dimensional finite element model of the mandible and masticatory muscles was produced with approximately 23,000 hexahedral elements. On this model, mesial and distal portions of the jaw were resected and bridged with a buccal and/or caudally positioned bridging plate.

Osteogenic uni- or bilateral form of the guided rapid maxillary expansion.

Surgically assisted rapid palatal expansion is an important treatment procedure in patients with constricted maxillae. Several surgical methods have been proposed to expand the maxilla bilaterally. A new technique was developed for performing a symmetric or asymmetric maxillary expansion guided by the stability of the mid-palatal area employing two osteotomy cuts on either side of mid-palatal suture.

The Endo-Distractor for preimplant mandibular regeneration.

Objective: A simple practical device for a new technique of vertical distraction osteogenesis was developed. The Endo-Distractor Krenkel was originally intended for the anterior regeneration of highly atrophic mandibles. The Endo-Distractor features several novelties.

Le Fort I sliding osteotomy--a procedure for stable inferior repositioning of the maxilla.

Introduction: Inferior repositioning of the maxilla for correction of vertical maxillary deficiency has been found to be associated with instability and a tendency to relapse. This can not be completely controlled by using bone grafts as relapse commences before complete integration of the graft.

Methods: Improved stability was sought by using rules of geometry when displacing the maxilla down a sloping plane.

[Acatalasemia--Takahara's disease].

The case of a 30 year old man with acatalasemia is presented. The congenital disorder is charaterized by a lack or major reduction of catalase, an enzyme that catalyzes the decomposition of hydrogen peroxide to oxygen and water. The defect is inherited in an autosomal recessive fashion.

2D-finite element analyses and histomorphology of lag screws with and without a biconcave washer.

For osteosynthesis and for bone transplant fixation in particular, a lag screw with a biconcave washer, the so called "Anchor Screw" (AS) has been introduced in maxillo-facial surgery. Using 2D-finite element analysis (FEA), the v. Mises and the circumferential stresses induced in underlying bone by this AS are analysed and compared to those under a conventional lag screw.

Treatment of mandibular-condylar fractures.

Particularly with true dislocation fractures, nonoperative treatment with maxillomandibular fixation followed by physiotherapeutic exercises leads to poor results, as was proved with axiography and clinical examinations. The main reason for this is the shortening and scarring of the condyloid process and the lack of function of the lateral pterygoid muscle. The condyle with its insertion of the muscle is usually displaced medially and anterially and nearly in touch with the origin on the pterygoid process so that protrusion by the muscle is no longer possible.

[Functional dynamic bridging plate and its use in the mandible].

The principle of the functionally dynamic bridging plate can be compared with the construction of a double bridge. The first bridge, which performs a protective function, is established by means of a plate which extends from one stump of the mandible to the other. The homogeneous, square-sectioned, central bar of the plate tolerates micromovements when stressed and demonstrates no predetermined breaking points.

Axial 'anchor' screw (lag screw with biconcave washer) or 'slanted-screw' plate for osteosynthesis of fractures of the mandibular condylar process.

Almost a quarter of all mandibular fractures are located in the condylar neck region and generally lead to disturbances of occlusion. Because they still possess active growth centres, children and adolescents can take advantage of the joint's remodelling capacity following conservative treatment of these fractures. Fractures with displacement of the condylar head in adults can interfere with function if they are not surgically reduced (Krenkel and Strobl, 1989).

The caudal mandibular reconstruction plate: a radiographic and histologic study of an autopsy specimen.

During autopsy, a reconstructed partial mandibular resection was recovered and subjected to histological examination. The mandible had been reconstructed 12 weeks earlier with a caudal plate and autologous cancellous bone from the iliac crest. Undecalcified microsections showed that the plate was firmly anchored by screws on both sides and on one side there was bony union.

[Cephalometric analysis of Class III patients after surgery].

The University of Innsbruck, Department of Dentistry, analysed the cephalograms of 23 prognathic patients whose dysgnathia was corrected by an osteotomy of the mandible only. The obtained results were compared with an analysis of the respective models. Documentation was obtained prior to surgery, post-operatively and during follow-up examinations over a period of at least six years.

[Effects of myofunctional disorders on occlusion following surgery for mesial bite].

In a follow-up study of 24 patients with mesial bite operated on at the Department of Oral and Maxillofacial Surgery, University of Innsbruck Medical School, relations between the outcome of sagittal splitting and myofunctional disorders were investigated. Orofacial imbalances of variable extent were found to be present in 16 of the patients followed up. Effects of myofunctional factors on occlusal position, occlusion, overbite and overjet are reviewed.

[Long-term outcome of functional treatment for high double-sided condylar fractures].

The conservative procedures widely used to treat fractures of the condylar neck seem to provide positive short-term benefits, but on long-term observation the results sometimes are not consistent with the early prognosis. We observed a patient (adult female) from the time of the accident for a period of 7 years. The patient suffered from a high double-sided fracture of the condylar neck combined with a multiple fracture in the frontal region of the mandible.