Karl Günter Wiese

Clefts in newborns are associated with severe morphological and functional impairment. Especially the lip is of importance as if the treatment result is unsatisfactory, it can lead to psychological changes in the patient. Different operative procedures have been developed over the last decades. The aim of the presented study was the comparison of the surgical techniques according to Millard and Pfeifer regarding the temporal development of the postoperative symmetry of the lip height and mouth width. Digitized photographs of patients from the department of oral and maxillofacial surgery at the University of Göttingen were evaluated from 1979 to 1996. With a video analysis program, the lip height and mouth width were analyzed regarding the symmetry. We demonstrated the symmetry values over a period of 8 years in order to show the influence of growth on postoperative results. The development of the vertical symmetry of the Philtrum and the lip vermillion on the cleft side in comparison to the healthy side behaves differently depending on Pfeifer and Millard. The lip height of the cleft lip was shorter in both techniques than on the healthy side, but Pfeifer’s difference was significantly more pronounced. The lip vermillion height on the cleft side was slightly shorter in the Millard group and markedly larger in the Pfeifer group. Both techniques can achieve good symmetry results for the vertical dimension of the lip. According to Pfeifer, the development of the horizontal dimension on the cleft side is bigger within the first 4 years than on the healthy side; according to the Millard technique, the horizontal development is smaller. These differences are greater within the first 6 years and approach between the 6th and 8th year. The Millard technique demonstrates better results concerning the philtrum and vermillion symmetry during growth within the first 6 years. Over the whole study period, growth corrects the philtrum and vermillion symmetry within the Pfeifer group.

The octamer-binding transcription factor 4 (Oct4) was originally described as a marker of embryonic stem cells. Recently, the role of Oct4 as a key regulator in pluripotency was shown by its ability to reprogram somatic cells in vitro, either alone or in concert with other factors. While artificial induction of pluripotency using transcription factors is possible in mammalian cell culture, it remains unknown whether a potential natural transfer mechanism might be of functional relevance in vivo. The stem cell based regeneration of deer antlers is a unique model for rapid and complete tissue regeneration in mammals and therefore most suitable to study such mechanisms. Here, the transfer of pluripotency factors from resident stem cell niche cells to differentiated cells could recruit more stem cells and start rapid tissue regeneration. We report on the ability of STRO-1⁺ deer antlerogenic mesenchymal stem cells (DaMSCs) to transport Oct4 via direct cell-to-cell connections. Upon cultivation in stem cell expansion medium, we observed nuclear Oct4 expression in nearly all cells. A number of these cells exhibit Oct4 expression not only in the nucleus, but also with perinuclear localisation and within far-ranging intercellular connections. Furthermore, many cells showed intercellular connections containing both F-actin and α-tubulin and through which transport could be observed. To proof that intercellular Oct4-transfer has functional consequences in recipient cells we used a co-culture approach with STRO-1⁺ DaMSCs and a murine embryonic fibroblast indicator cell line (Oct4-GFP MEF). In this cell line a reporter gene (GFP) under the control of an Oct4 responsive element is only expressed in the presence of Oct4. GFP expression in Oct4-GFP cells started after 24 hours of co-culture providing evidence of Oct4 transfer from STRO-1⁺ DaMSCs to Oct4-GFP MEF target cells. Our findings indicate a possible mechanism for the expansion of a resident stem cell niche by induction of pluripotency in surrounding non-niche cells via transfer of transcription factors through intercellular connections. This provides a new approach to explain the rapid annual antler regrowth.

The annual regeneration of deer antlers is a unique developmental event in mammals, which as a rule possess only a very limited capacity to regenerate lost appendages. Studying antler regeneration can therefore provide a deeper insight into the mechanisms that prevent limb regeneration in humans and other mammals, and, with regard to medical treatments, may possibly even show ways how to overcome these limitations. Traditionally, antler regeneration has been characterized as a process involving the formation of a blastema from de-differentiated cells. More recently it has, however, been hypothesized that antler regeneration is a stem cell-based process. Thus far, direct evidence for the presence of stem cells in primary or regenerating antlers was lacking. Here we demonstrate the presence of cells positive for the mesenchymal stem cell marker STRO-1 in the chondrogenic growth zone and the perivascular tissue of the cartilaginous zone in primary and regenerating antlers as well as in the pedicle of fallow deer (Dama dama). In addition, cells positive for the stem cell/progenitor cell markers STRO-1, CD133 and CD271 (LNGFR) were isolated from the growth zones of regenerating fallow deer antlers as well as the pedicle periosteum and cultivated for extended periods of time. We found evidence that STRO-1⁺ cells isolated from the different locations are able to differentiate in vitro along the osteogenic and adipogenic lineages. Our results support the view that the annual process of antler regeneration might depend on the periodic activation of mesenchymal progenitor cells located in the pedicle periosteum. The findings of the present study indicate that not only limited tissue regeneration, but also extensive appendage regeneration in a postnatal mammal can occur as a stem cell-based process.

This retrospective study included 148 patients who were evaluated for postoperative long-term results after osteosynthesis of isolated zygoma fractures. The influence of open reposition of the zygomaticoalveolar crest to middle face symmetry was evaluated quantitatively with a zygometer. In dependence on operative management patients were divided into two groups: In group I zygomaticofrontal suture (1-point-fixation) and infra-orbital rim were exposed (2-point-fixation), followed by osteosynthesis. In group II additional exposure of zygomaticoalveolar crest was performed and if required osteosynthesis was performed (3-point-fixation). For osteosynthetic reconstruction of isolated zygoma fractures the only 2-point-fixation is usually enough to achieve lateral middle face symmetry. In all cases zygomaticofrontal suture and alternatively infra-orbital rim or respectively zygomaticoalveolar crest should be supplied osteosynthetically. A further 3-point-fixation is indicated only in exceptional cases--for example comminuted fractures of lateral middle face columns. For an exact anatomical reposition of zygoma fractures the exposition and possible osteosynthesis of zygomaticoalveolar crest is recommended.

Fragestellung. Es sollte geprüft werden, welche Wertigkeit die B-Scan-Sonographie, 3D-Sonographie, Röntgendiagnostik und Sinuskopie zur Diagnostik von Kieferhöhlenveränderungen nach Sinusbodenelevation besitzen. Material und Methode. Bei 33 Patienten wurden vor der Sinusbodenelevation sowie 1 Woche und 6 Monate postoperativ die Kieferhöhlen mittels eines 7,5-MHz-Linearschallkopfs sowie 3D-sonographisch untersucht. Die sonographischen Befunde der Nasennebenhöhle, die röntgenologischen Nasennebenhöhlenaufnahmen, das Dental-CT oder Orthopantomogramm und die sinuskopischen Befunde wurden verglichen. Die Sinuskopien erfolgten nur im Rahmen der Sinusbodenelevation und bei der Implantatfreilegung nach 6 Monaten. Ergebnisse. Insgesamt wurden 56 Sinusbodenelevationen mit simultaner Knochentransplantation durchgeführt. Präoperativ waren in allen Untersuchungsverfahren keine Auffälligkeiten in den Kieferhöhlen nachweisbar. 1 Woche postoperativ bestanden in 40 Kieferhöhlen Schwellungen der Mukosa, die sowohl sonographisch als auch röntgenologisch nachweisbar waren. Nach der Einheilungsphase der Knochentransplantate von 6 Monaten persistierten in 3 Kieferhöhlen sowohl sonographisch als auch röntgenologisch als auch sinuskopisch identifizierbare polypöse Veränderungen. Die 3D-Sonographie erhöhte dabei die Vergleichbarkeit und die Reproduzierbarkeit der sonographischen Ergebnisse. Schlussfolgerungen. Wegen der fehlenden Strahlenbelastung, Kostengünstigkeit und der beliebig oft durchführbaren Untersuchungsmöglichkeit ist die Sonographie als primäres Screeningverfahren im Recall geeignet. Bei unauffälligen Sonogrammen, aber klinischer Symptomatik sollten dann das CT, das MRT oder die Sinuskopie eingesetzt werden, um Prozesse an der Sinushinterwand sicher auszuschließen. Problem. The aim of this study was to determine which technique – B-scan sonography, 3D sonography, X-ray, or endoscopy – is the most effective for diagnosis in changes of the maxillary sinus after sinus lift and simultaneous augmentation. Material and methods. In 33 patients the maxillary sinus was examined before sinus lift, 1 week and 6 months postoperatively with a 7.5-MHz linear scanner and 3D sonography. At the same time, the sonographic results were compared with the X-ray as well as the endoscopic results. Endoscopy of the maxillary sinus was only applied during the sinus lift operation and the abutment operation after 6 months. Results. A total of 56 operations of sinus lift and simultaneous augmentation with autogenous bone were carried out. Preoperatively, there where no pathological findings detectable in the maxillary sinus. One week postoperatively, the X-rays as well as the sonographic images revealed thickening of the mucosa in 40 maxillary sinuses. After the healing period of 6 months, polyposa was still detected in three cases sonographically, in the radiographic follow-up as well as endoscopically. The sonographic 3D imaging of the maxillary sinus improved the spatial visualization of postoperative changes in the maxillary sinus and the reliability of the diagnosis. Conclusion. Due to the lack of radiation, the cost effectiveness, and its reproducibility, sonography is suitable as a primary screening technique in recall. In cases of normal sonographic findings but clinical symptoms, CT, MRT, and endoscopy should be performed to exclude pathological processes of the posterior maxillary sinus.

Although widely used, the radial forearm flap has been criticized for the poor quality of its donor site. Attempts to avoid donor-site problems have concentrated on the elaboration of the split-thickness and full-thickness skin graft methods of reconstruction. Skin grafts frequently fail over the flexor carpi radialis tendon, leading to chronic skin breakdown or, at best, tendon adhesion. Tissue expansion appears to be a good alternative that allows the use of local tissues to ultimately improve the forearm donor-site appearance. To avoid the disadvantages of traditional silicone balloon expanders (such as pressure peaks, infection, the valve at a distance from the expander, postoperative fillings), an osmotically active system was used. In an 18-month prospective study, 10 osmotically active hydrogel tissue expanders were placed on the forearms of 10 patients. The radial forearm flap was performed for intraoral reconstruction after surgical resection of oral cavity malignancies. The study showed that, in nine out of 10 patients, the expanded skin achieved was sufficient to cover the donor site after raising the forearm flap. Additionally, the expansion-related swelling pressure was well tolerated by the patients, the cosmetic results were very satisfactory, and the incidence of complications was very low. By using osmotically active hydrogel tissue expanders, there is no postoperative filling and no risk of complications arising from defective balloon expanders, filling valves, or missing ports. (Plast. Reconstr. Surg. 108: 1, 2001.)

The aim of this study was to investigate the swelling properties and the biocompatibility of a novel tissue expander material. The self-inflating material is a hydrogel consisting of a modified copolymer of methylmethacrylate and N-vinyl-2-pyrrolidone, which takes up water by osmosis. To increase the swelling volume, the primarily neutral gel material was modified by converting it into an ionized gel. To study the swelling and pressure behavior of the material, the anhydrous gel cylinders were equilibrated in distilled water, saline, and sugar solutions. The biocompatibility was investigated in cell culture. We tested the hydrogel eluate after swelling for cytotoxicity and mutagenicity using the cell lines MRC-5 and P3X63 Ag8 653 (Ag8). Furthermore, particles of the material were added to cell cultures to induce foreign body reactions and to verify its influence on monocyte differentiation. The material has a swelling capacity (Q = maximum swelling volume/anhydrous volume) of 5 to 50 depending on the degree of ionization of the polymer network. In this study, two polymer modifications with a swelling equilibrium of Q = 11.1 and 30 in water were tested. The swelling ratio also depends on concentration and ion content of the equilibration medium. The highest swelling capacity was found in water, the lowest in Ringer's solution. The swelling of the anhydrous material with the swelling capacity of Q = 11.1 fits best the average purpose of material properties for tissue expansion and generates a maximal hydrostatic pressure of approximately 235 mmHg. Effects on cell proliferation were detected only at the highest eluate concentration tested (i.e., eluate: culture medium = 1:1), which was far beyond physiological values, whereas mutagenicity was absent. Monocytes neither migrated nor tightly attached to the hydrogel. They neither phagocytose the material nor did they show any sign of a foreign body reaction, e.g., formation of multinucleated giant cells or monocyte proliferation. In the presence of hydrogel material, the differentiation processes of monocytes to macrophages or dendritic cells, respectively, were found to be undisturbed. From these results, we conclude that there is a high biocompatibility of the expander material, which may be a favorable and interesting candidate for further clinical applications. © 2000 John Wiley & Sons, Inc. J Biomed Mater Res 54: 179–188, 2001

· Background: Clinical anophthalmia is characterized by the absence of an eyeball within the orbit and can result in overall growth retardation of the facial skeleton. The goal of treatment consists of fitting a serial prosthesis following rapid expansion of the contracted socket as soon as possible to achieve cosmetically acceptable eyelid and orbital symmetry. · Methods: Four children, aged 3–11 months, were treated by implantation of an anhydrous, highly hydrophilic tissue expander into the rudimentary conjunctival sac. With hydration of up to 98% in 72 h, the copolymer of methylmethacrylate and vinylpyrrolidone acts like an osmotically self-inducing socket expander. · Results: In the course of 2 months the previous contracted socket was enlarged, the horizontal lid length increased and the hydrated expander could be exchanged for a custom-made glass prosthesis. · Conclusion: Preliminary results suggest that this new device can be used to avoid early plastic surgery of the eyelid. In addition, it also may enlarge the volume of the bony orbit.