A comprehensive classification of craniofacial fractures: postmortem and clinical studies with two- and three-dimensional computed tomography.

A comprehensive classification of midfacial/craniofacial fractures, based on two- and three-dimensional computed tomography (2D and 3D-CT) is presented. We performed a postmortem analysis of 24 patients who had died from trauma with signs of craniofacial fractures, based on 2D and 3D-CT studies with pathoanatomical findings. In addition, CT findings for 100 patients with craniofacial injuries requiring an emergency CT were correlated with surgical findings and follow-up results.

The titanium surface texture effects adherence and growth of human gingival keratinocytes and human maxillar osteoblast-like cells in vitro.

The adhesion, orientation and proliferation of human gingival epithelial cells and human maxillar osteoblast-like cells in primary and secondary culture were studied on glossy polished, sandblasted and plasma-sprayed titanium surfaces by scanning electron microscopy and in thin sections. The primary cultured explants of human gingival epithelial cells attached, spread and proliferated on all titanium surfaces with the greatest extension on the polished and the smallest extension on plasma-sprayed surfaces. In secondary suspension cultures of gingival keratinocytes, attachment spreading and growth was only observed on polished and plasma-sprayed surfaces, but not on sandblasted surfaces.

[Mandibular osteomyelitis after mandibular conduction anesthesia].

Several complications following a mandibular nerve block were reported in the literature. In some cases pterygomandibular abscess formation may be caused by mandibular needle injections. There is no report of odontogenic osteomyelitis of the ascending mandibular ramus in the literature.

[Selection of the method of surgical approach in plate osteosynthesis of mandibular fractures].

Background: Plateosteosynthesis by intraoral approach of mandibular fractures gives the best cosmetical result but presents a rather difficult procedure.

Aims: Comparison of intra- versus extraoral approach in plateosteosynthesis of mandibular fractures.

Methods: Plate type, experience of the surgeon, age and sex of the patient, as well as hospital stay and rate of the septic complications were analysed retrospectively in 248 patients of the OMF Department (University Freiburg) with mandibular fractures with respect in view of the operative approach used.

[Modifications in cultivating gingival keratinocytes].

Gingival keratinocyte grafts are usually cultured using 3T3 mouse fibroblasts as feeder cells and fetal calf serum as growth factor. These additives entail risks due to xenogenic DNA and protein. Therefore the explant and the disperse culture technique free of feeder cells were compared, and autogenous human serum was tested.

The development of the ITI Dental Implant System as a model for the cooperation between research and industry.

For thirty years now oral implants and methods for implantation have been developed further to assure a lifetime stability of these devices and to optimize function and esthetics. Coming from osteosynthesis the Institut Straumann in cooperation with leading clinicians had a considerable share in this development. Out of this longtime cooperation an institutionalized form was devised, where clinicians, material scientists and engineers were united in the International Team for oral Implantology (ITI).

Transalveolar fixation of the peri-implant soft tissue in the mandible: surgical method and clinical follow-up.

Purpose: Firm, immobile mucosa around endosteal implants is one prerequisite for a reliable long-term result. In the atrophic mandible, this may be achieved by a vestibuloplasty on the facial side. However, on the lingual side, the floor of the mouth is often high and the mucosa mobile, especially after unintentional detachment of the lingual flap during implant surgery.

Titanium deposition in regional lymph nodes after insertion of titanium screw implants in maxillofacial region.

The deposition of titanium in regional lymph nodes was studied after insertion of endosseous, plasma-spray-coated titanium screw implants in a total of 19 beagle dogs. Five additional animals with no implants served as the control group. After killing the animals 9 months postoperatively, the regional lymph nodes were carefully excised, and samples were prepared for histologic examination.

Cellular and molecular biological events at the implant interface.

Since implants attain and maintain contact with the body environment through their surfaces, the interfacial interaction between implant bed and implant surface could be a determinant of the implant's performance. This study used osteoblasts to test the ability of different ceramic and metallic surfaces to bind fibronectin and to support cell attachment, adhesion, migration and synthesis of extracellular matrix. The results showed active molecular and cellular interaction between the cells and the surfaces.

Interfacial reactions of osteoblasts to dental and implant materials.

Scanning electron microscopy was used to study the response of osteoblasts to various surfaces including ceramics and glasses as well as steel and titanium. Hydroxylapatite, tricalcium phosphate, bioglass, steel, and titanium supported cell adhesion. However, the toxic effects of the In-Ceram (Vita, Bad Säckingen, Germany), and feldspar ceramic and glaze were severe enough to cause verrucous necrosis that was identifiable after 2 days of culture.

Mechanisms and structure of the bond between bone and hydroxyapatite ceramics.

Two assays were carried out to investigate the postulates that dissolution/reprecipitation phenomena and epistaxis are involved in the formation of the bond between sintered hydroxyapatite (HA) and bone. HA was exposed to a physiologic solution and the ions going into solution quantified using inductively coupled plasma (ICP) emission spectroscopy. The HA was retrieved and examined using scanning electron microscopy (SEM).

Comparison of transcutaneous incisions used for exposure of the infraorbital rim and orbital floor: a retrospective study.

One hundred and five patients were investigated for functional and aesthetic impairments following treatment of orbital trauma through subciliary, mid-lower eyelid, or infraorbital incisions. The progress of impairments with time was assessed, and the merits and shortcomings of each of the three approaches were established. The results showed that impairments persisting up to 6 months postoperatively have virtually not receded even after 6 years.

[Nasal intubation for frontobasal fractures?].

In most cases the surgical management of craniofacial fractures involves a correction of the occlusion. This requires nasal intubation. In a frontobasal fracture with simultaneous CSF fistula, nasal intubation is thought to increase the risk of meningitis.

[Severe atrophy of the alveolar ridge in edentulous patients. Combined treatment using bone grafts and screw implants].

In cases of advanced alveolar ridge atrophy, when the bone available for endosseous implants is not sufficient, endosseous implants are combined with augmentation of the alveolar ridge by means of autologous bone transplants. Depending on the type of atrophy found, the authors use three different surgical procedures: onlay technique, sandwich technique and alveolar extension technique. In all cases functional loading of the implants was performed by way of an entirely implant-supported bridgework.

Penicillin concentration in the compact bone of the mandible.

During surgical removal of impacted third molars, the concentration of Penicillin G was determined in the compact bone of the mandible. Fifteen patients received 5 million IU and 15 received 10 million IU of Penicillin G intravenously as a single dose before surgery began. In both groups concentrations of penicillin with a bactericidal effect on most pathogenically relevant oral bacteria were detected during osteotomy.

Cultured gingival epithelium. A possible suitable material for pre-prosthetic surgery.

In cultivating gingival epithelium from people up to the age of 66 years it is possible to gain a differentiated mucosal tissue sheet that is more than 100 times the size of the original biopsy surface. The morphological characteristics are a prickle cell layer with polygonal cells and a basal cell layer with flattened cells. Desmosomes, tonofibrils and microplicae at the superficial side of the epithelium are typical features.

Radiation and osteosynthesis. Dosimetry on an irradiation phantom.

An irradiation phantom was used to measure dose increases using the backscatter of different materials (titanium, steel, lead, aluminium). Telecobalt-60 and 8-MV photons were used for the irradiation. The irradiation dose was measured by means of a defined X-ray film blackening.

Interaction of osteogenic cells with hydroxylapatite implant materials in vitro and in vivo.

In a series of scanning electron microscopic studies, the reaction of osteogenic cells to hydroxylapatite (HA) implant materials was investigated in culture and following implantation. Tissue components as found in normal rat and dog bone were identified at the interface in both test systems. In vivo, implant bed cells showed an intimate contact with the HA surfaces.

Primary reconstruction with AO-miniplates after severe cranio-maxillofacial trauma.

Miniplate osteosynthesis has proven to be an invaluable aid when used in severe cranio-maxillo-facial trauma and has thus eliminated the necessity for external fixation devices. Primary exact anatomical reduction, and fixation of the fragments with miniplates, gives both good aesthetic and functional results.