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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. On the basis of the analysis of a total of 377 fractures a classification system is proposed. The system is based on the use of the AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) scheme, defining three types (A, B, C), three groups within each type (e.g. A1, A2, A3) and three subgroups within each group (e.g. A1.1, A1.2, A1.3) with increasing severity from A1.1 (lowest) to C3.3 (highest). The craniofacial region is divided into three units: the lower midface (I), the upper midface (II) and the craniobasal-facial unit (III). Lateral and central fractures are also distinguished. Type A fractures are non-displaced fractures, type B are displaced fractures and type C are complex/defect fractures. Groups A1, B1 and C1 comprise fractures of an isolated unit; groups A2, B2 and C2, combined fractures without involvement of the skull base; and groups A3, B3 and C3 are those combined fractures with involvement of the skull base. A correlation between the severity of the fracture and (i). the number of posttraumatic functional limitations (Spearman rank test, correlation coefficient r=0.42), (ii). the need for bone grafting or dural plastic (r=0.39) and (iii). facial asymmetry (r=0.37), was observed. The proposed classification system allows standardised documentation of midfacial and craniofacial fractures, including those not precisely defined by the Le Fort classification scheme.

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. Moreover, the attachment of these cells depended on the seeding concentration as well as on the coating with fetal calf serum. Cells on polished surfaces developed an extremely flat cell shape, but on sandblasted and plasma-sprayed surfaces a more cuboidal shape. In contrast human maxillar osteoblasts seeded as secondary suspension cultures attached very well to all three differently textured titanium surfaces and showed identical growth patterns independent of the titanium surface structure. These findings suggest that cell morphology, orientation, proliferation and adhesion of human gingival epithelial cells in primary or secondary culture are dependent on the texture of the titanium surface whereas no such differences were observed for maxillar osteoblast-like cells. In conclusion, the soft tissue integration and response is more influenced by the surface texture than the process of osseointegration.

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., Results: The method of osteosynthesis was found to be the strongest determinant. Concerning the surgical approach significant correlation was found between age and sex, and surgical experience. Operative approach was found to have no effect on hospitalization and septic complications., Conclusion: Operative approach does not have either medical nor economical consequences in the surgical management of mandibula fractures.

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. Here two patients with osteomyelitis of the ascending ramus following a mandibular nerve block injection are presented.

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. Twelve halved gingival biopsies were trypsinized and cultured as single-cell suspensions, the other halves were cultured as explants. Six halved biopsies were cultured in autogenous serum, the other halves in fetal calf serum. Growth, morphology and cell biological aspects were compared. The single-cell suspensions did not form a confluent epithelial layer, whereas all explants formed confluent primary gingival keratinocyte cultures. The keratinocytes' growth in autogenous serum was equivalent to that in fetal calf serum. Morphology and cytokeratin expression were identical. The explant technique combined with autogenous serum can be used for culturing gingival autografts as well as for individual cultures for special issues.

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). This scientific organization, although legally and financially independent from Institut Straumann, works in close cooperation with the company in an unique form of symbiosis. The ITI takes care of research and education of clinicians and practitioners and it gives the needed input for the development of new products to the Institut Straumann as its exclusive licensee. The company again pays license fees to the ITI Foundation enabling thus a continuous scientific clinical research. Over many years a whole philosophy and implant system - the ITI Dental Implant System - was developed this way with its sound scientific background.

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. To overcome this problem, a surgical technique applying a transalveolar suture circumscribing the inserted implants was developed., Patients and Methods: The operation was performed in six patients, and they were evaluated over a period of more than 18 months., Results: There was a clinically significant increase in fixed mucosa behind the implants compared with a control group of six patients with a similar preoperative and intraoperative status., Conclusion: A localized lowering of the floor of the mouth limited to the peri-implant region using this technique can successfully improve the lingual mucosa around implants.

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. Other samples were used to identify foreign particles by energy-dispersive x-ray analysis and for measurement of the titanium concentration in the tissue by flameless atomic absorption spectroscopy. Very fine foreign-body particles could be seen in the histologic sections, and they were identified as titanium by energy-dispersive x-ray analysis. The atomic absorption analysis for titanium revealed a significantly higher concentration in the group with implants. The presence of very fine, poorly attached particles on the plasma-sprayed titanium surface suggests that these particles may be mechanically dislodged from the surface on insertion of the implants. This suggests that the fine particles may be transported by phagocytes to the regional lymph nodes, where they could be found without any signs of inflammation or foreign-body reaction.

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. Extracellular matrix synthesis was demonstrated on surfaces that did not subject the cells to toxicity embarrassment. It is concluded that the surfaces of implants should not be designed to be mere bystanders in the interfacial scenario. Instead they should be conceived with a view to enabling them to interact positively with the molecules responsible for would healing, interfacial tissue morphogenesis and repair.

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. After 10 days in culture only the peripheral portions of these specimens were still occupied by cells; the cells in the central portion of the circular specimens had succumbed to necrosis. It was concluded that scanning electron microscopy is useful in identifying the response of cells to materials. Pathologic changes are not recognizable if they are limited to the internal structure of the cell, but readily discernible when they impinge on the morphologic integrity of the cell surface.

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). In the second assay, HA was implanted into Alsatian femura. Following retrieval, specimens were prepared and studied with SEM, at magnifications usually reserved for transmission electron microscopy (TEM). In vitro the HA surface composition appeared to shift to the acidic (calcium-deficient) direction. The HA surfaces in both assays underwent a dissolution/reprecipitation degradation of varying severity, forming a recrystallization layer of spherocrystallites. Two modes of bone bonding to implanted HA were identified: (1) bone tissue components bonded to HA via a recrystallization zone similar in structure to the reprecipitation layer in the corrosion assay, and (2) bone tissue components bonded directly to HA crystals with no morphologically discernible signs of dissolution embarrassment. The formation of the bone/HA bond seems to involve dissolution/reprecipitation phenomena. What is believed to be the first morphological evidence of epitaxial growth involvement in the formation of this bond is presented.

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. The infraorbital incision showed the highest frequency of impairments, followed by the subciliary incision. The mid-lower eyelid incision showed the best results, with an impairment frequency well below those of the other two approaches. This approach seems to combine the advantages of the infraorbital incision with the unnoticeable scar formation associated with the subciliary incision.

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. Results to date indicate that initial postoperative resorption is followed by a virtual standstill once the implants have been loaded.

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. An analysis of the records of 160 patients with frontobasal fractures and CSF fistulae revealed that the route of intubation had no influence on the post-operative complication rate. Nasal intubation is therefore not contraindicated in frontobasal fractures with CSF fistulae.

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. Taking into account the considerable interindividual variation, the one-shot application of 10 million IU of Penicillin G was more effective in certain cases than the 5 million IU dose. The factors influencing the decision on the high single-dose application include expected length of operation, body weight, kidney function, and infusion period. Assuming that in intraoral osteotomies the bone becomes contaminated with bacteria that are highly sensitive to penicillins, the results indicate that preoperative infusion of Penicillin G could be an effective method of preventing wound infection.

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. There is a cell biological differentiation as the distinct binding of lectins and of a cytokeratin antibody proves. The multiplication in surface area, the possibility of using cells of senior patients and the morphological and cell biological differentiation of cultured gingival epithelium are advantages in its application for the autologous bridging of intraoral defects.

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. The most important parameter was to find out whether under simulated conditions, undesirable hot spots occur. We were able to demonstrate that a 12.5 to 16% increase in the radiation dose can be observed for titanium and steel at a distance of 0.45 mm from the metal specimen. A comparison between titanium and steel did not demonstrate a relevant advantage for titanium. Therefore, adjuvant percutaneous radiation therapy should not have any influence on the life of the implant, if the soft tissue layer is of sufficient thickness. The available literature is reviewed and presented in tables.

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. Osteoblasts deposited organic matrix and bone mineral in direct apposition to HA, with no evidence of encapsulation or granulation tissue. The development of such a direct spatial relationship appears to involve mechanisms more encompassing than epitaxis.

Thirty-two patients with histologically proven carcinoma of the oral tongue, Stage T1-3, were analyzed retrospectively. They were treated from January 1964 through July 1980 in Freiburg by interstitial implantation with Au-198-seeds for the primary tumor management. Out of 25 patients with complete follow-up, one patient developed a local recurrence. In three patients, regional lymph node metastases occurred, once after prior adjuvant radiotherapy to the regional lymph nodes area, and in two patients after exclusive interstitial radiotherapy to the tumor of the tongue. The overall five-year survival rate was 52% for all stages (overall group), 75% for Stage T1 and 44% for Stages T2-3. The corrected five-year survival rate was 75% for all stages, 86% for Stage T1 and 71% for Stages T2-3. The method of 198Au-seed implantation as it is practiced in Freiburg is discussed, as well as the radiation exposure of the personnel.

A case was reported in which a foreign body was identified in the maxillary sinus during the course of a radiologic dental examination. The foreign body proved to be a calculus. Analysis of the calculus revealed no foreign body responsible for the crystallization. The possibility of local formation of a calculus of the maxillary antrum was discussed.

Using the data acquired from our catamnestic survey, we were able to establish a broad catalogue of complications involved with impacted and displaced teeth. Given these complications, it is not medically responsible to leave impacted and displaced teeth in the jaw, even if they are asymptomatic. The risks increase considerably with age. Late operative removal of such teeth can be a dangerous intervention due to local complications such as abscesses, cysts, osteomyelitis, tumors, systemic diseases, and age-related changes in the cardiovascular system.

The use of implants in bone represents an extension of prosthetic possibilities. Clinical cases are used to demonstrate how additional supports can be created by means of implants of Linkow-blades which allow the incorporation of periodontally damaged teeth into prosthetic care. In addition the use of transdental fixation in the stabilisation of badly loosened teeth is pointed out.

Nearly all types of mandibular fractures have been treated successfully by compression osteosynthesis. Special instruments are required, the bone must be treated correctly, the fragments must be reduced exactly, and the plate must be adapted exactly. Basically, only lag screws are used when there is a lamellar fracture and when a large surface permits support; the dynamic compression plate with oblique lateral screw holes is indicated when the fracture runs transversely. The dynamic compression plate with oblique lateral holes and the additional inlay portion is indicated in oblique fractures and when the alveolar process is weak.

Even minor facial deformities impose a burden on the personality: the face is vital for its identification of the individual. Defects in facial form cannot be concealed. The origins of most deformities lie in the bony skeleton. They may be either congenital or acquired. In the congenital deformities, form, size and function are disturbed during the course of development, whereas in the acquired deformities parts of the face are lost by surgery or trauma. Occlusion is always affected in deformities of the central and lower thirds of the face. Conversely, massive disturbances of occlusion have repercussions on facial form. Congenital deformities should be corrected early if function is also disturbed, but additional correction is often necessary after growth is complete. If only the proportions of the bony skeleton of the face are affected, the deformity is corrected after the termination of growth. Reconstruction of normal occlusion is essential in the correction of facial deformities. Tissue missing as a result of surgery or trauma is replaced by grafts. Disturbances of development caused by local disease (neoplasia or osteomyelitis) affecting the face constitute an intermediate form of deformity. These defects should receive only functional correction during growth, final reconstruction not being undertaken until it is complete.

With consideration of the special situation in periorbital fractures, the fundamental differences between wire and metal plast osteosynthesis was demonstrated on the basis of mathematical calculations, mechanical considerations and tension optical experiments. We further report on the different behaviour of both methods of osteosynthesis in tension experiments which demonstrate the distinct superiority of the metal plate.

Cleft patients who have undergone surgery often show considerable inhibition in the sagittal development of the mid-face after completed growth. This is partly attributed to scar contraction in the lip region following surgery. The present investigation deals with the etiological factors involved in the development disturbances caused by the cleft in the maxilla of 100 cleft patients. Particular attention was paid as to the unfavourable effect of the operated cleft lip. This was tested electromyographically and correlation between the electromyographic and the skeletal measurements was sought. Electromyographic changes in lip activity during orthodontic treatment was also investigated. The effect of these changes is discussed.

The most frequent swellings in the maxillofacial region can be traced to odontogenic inflammations. Chronic dental foci exacerbate and break through the soft tissue layer surrounding the jaw. There the purulent material quickly spreads along the muscular pocket and simulates a phlegomonous inflammation. Inflammations of the individual soft part niches have characteristic symptoms. Because of the loose interconnections the infectious material can spread very quickly into the parapharyngeal space and from there downwards into the mediastinum or upwards into the base of the skull. Because of the danger of an advance in these spaces, it will be necessary to incise the swellings on time.

The principles and techniques of rigid plate and screw fixation for fractures of the mid and upper face are presented. These techniques offer advantages for the repair of fractures in these area, as well as for the stabilization of planned osteotomies.

A new procedure for apical closure after apical root resection with a metal filling is presented which is easy to handle with appropriately standardized equipment and ensures exact apical closure. By conical preparation of the whole root, a standardized metal peg which resists distortion can be used for anchoring the crown prosthesis without further preparation. Temporarily a standardized guttapercha peg can be used for closure. Even if renewed work on the root becomes necessary later, the apical metal closure remains firm because of its wedging.

The treatment of fractures and osteotomies of the mandible and the midface show very different problems. The mandible must be treated in a stable and the midface in a static way. Due to the different bio-mechanics and topography of these bony structures, the advantages and disadvantages of treating a fracture in the maxillo-facial-region by the means of osteosynthesis will be discussed.