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991.
Zusammenfassung Die Osteotomie des Oberkiefers in der Le-Fort-I-Ebene, die heute routinemäßig in der Down-fracture-Technik durchgeführt wird, hat die chirurgische Behandlung skelettaler Dysgnathien grundlegend verändert. Sie ermöglicht eine dreidimensionale Korrektur des Oberkiefers und damit des gesamten Gesichtsschädels. Darüber hinaus kann der Oberkieferzahnbogen, zusätzlich zu einer Verlagerung des gesamten Oberkiefers, durch eine zusätzliche sagittale und transversale Osteotomie erweitert, verschmälert und verkürzt werden. Die Planung einer Oberkieferosteotomie erfolgt anhand des klinischen Bildes, der Kiefermodelle und des Fernröntgenbildes. Dabei muß der Unterkiefer frühzeitig mit in die Planung einbezogen werden, da er durch die Autorotation im Gelenk den Verlagerungen des Oberkiefers folgt. Erst durch eine gleichzeitige Osteotomie auch des Unterkiefers ergibt sich ein weites Indikationsspektrum für die Oberkieferosteotomie. Bei einer kombinierten Ober- und Unterkieferosteotomie ist praktisch jedes gewünschte Profil im unteren Gesichtsdrittel erzielbar.
Summary The osteotomy of the maxilla using the Le Fort I technique, today routinely performed in the down-fracture-technique, has changed surgical corrections of dentofacial deformities fundamentally. It offers a three-dimensional correction of the maxilla and also of the whole facial skull. Furthermore the upper dental arch can be expanded, intruded and shortened using a sagittal or transversal osteotomy in addition to a complete transposition of the maxilla. Planning of a maxillary osteotomy is performed under consideration of the clinical situation, the casts and the lateral cephalogram. The mandible must be considered at an early state of the preoperative planning, since the mandible will follow all transpositions of the maxilla by rotating with the TMJ. Only by performing a simultaneous osteotomy of the mandible, a broad spectrum of indications for maxillary osteotomy will result and practically every desired profile of the lower third of the face can be achieved using combined maxillary and mandibular osteotomies.
  相似文献   
992.
993.
Glass ionomer restorative cement offers the clinician an alternative to bonded composite resin for restoration of certain lesions in primary teeth. This article details a step-by-step procedure for restoration of a smooth surface carious lesion in a primary incisor using an encapsulated glass ionomer restorative material and reviews advantages and limitations of the cement. A light-hardened glass ionomer liner/base that has proven useful as an enamel and dentin restorative is also described.  相似文献   
994.
To produce hybrids, one member of the parental line is genetically made male-sterile. This male-sterile trait is encoded by mitochondria so that it is maternally inherited. Consequently, the progeny of a male-sterile plant is fully sterile. Nevertheless, during the handling of cytoplasmic male-sterile seed stocks, some mixture with seeds of the maintainer lines can occur. Up to the present time, the only way to check the homogeneity of the cytoplasmic male-sterile seed stock was to grow the plants until flowering time. We have developed a method which can be used immediately after the harvest, allowing us to check samples from both sunflower and sugar beet. We used the mitochondrial plasmid, present only in the maintainer lines, as a probe for the total nucleic acids prepared from the cytoplasmic male-sterile seed stocks which might be contaminated. The signals compared to those of samples artificially contaminated allow us to measure as few as one male-fertile seed in 1000 seeds in a rapid and accurate manner.  相似文献   
995.
996.
The following pages try to offer some ways of arguing against pesimism in our health administration culture. In fact, the review of a wide range of feasible reforms of our health system undertaken in this paper gives some clues for a better implementation of the a priori advantages of public health systems. These advantages are not achieved today because of some dysfunctionalities of daily management. To rationalize resources distribution, to evaluate the results, to eliminate unnecessary administrative control, to coordinate responsibility and budgeting centers, to introduce free choice as a response to public demand, and to simulate marketing by private production of public services are elements suggested in this paper to improve public health services management.  相似文献   
997.
998.
In summary, factors to consider in treatment are (1) the patient's age; (2) the flexibility of the condition; (3) the severity of deformity; (4) the presence of equinus; (5) abnormal shoe wear; and (6) the symptoms. When a child presents with severe flexible flatfoot one should rule out an underlying neuromuscular disorder and perform a complete biomechanical evaluation to ascertain any rotational or angular conditions of the legs that might influence the treatment. If a child is in group 1 (ages 4 to 7), a Helfet heel seat with a medial plantar wedge is usually adequate treatment. In the group II (ages 8 to 12) adolescent with flexible flatfoot, more control of the calcaneal eversion is needed. This is obtained by using a device constructed from a plaster mold taken while the foot is in neutral position. This UCBL type of device must usually extend to the metatarsal heads and be elevated on the medial and lateral sides. The group III (ages 13 to 17) adolescent usually has the additional problem of a forefoot varus, which must be controlled using a forefoot post. It is also not unusual to have to add additional wedging inside the heel of the shoe to invert the heel.  相似文献   
999.
The authors describe a method for silicone intubation of a single patent canaliculus associated with a nasolacrimal duct obstruction. Although bicanalicular intubation is always preferable when possible, unicanalicular stenting is necessary when only one canaliculus is patent. A chief advantage of this technique is that the lacrimal stent is inaccessible to the child and thus cannot be accidentally pulled out.  相似文献   
1000.
D J Harris  G O Waring  L L Burk 《Ophthalmology》1989,96(11):1597-1607
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty.  相似文献   
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