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991.
This prospective study was carried out at the Cleft Lip and Palate Centre at King Abdullah University Hospital and Maxillofacial Unit at Jordan University of Science and Technology during the period of 2000 to 2006. The sample consisted of 77 secondary alveolar bone grafts (62 patients), which were performed according to the same standardized surgical technique by a single maxillofacial surgeon.The objective was to assess the outcome of secondary alveolar bone grafting (SABG) before (early SABG) and after (late SABG) the eruption of the permanent maxillary canine in unilateral and bilateral Jordanian cleft subjects. Patients were divided into four groups: early unilateral SABG (22), late unilateral SABG (25), early bilateral SABG (8), and late bilateral SABG (7). Follow-up period ranged from 6 months to 5 years. Periapical or occlusal radiographs were used to assess the outcome of SABG. The degree of bony fill in the cleft area was assessed using the 4-point Kindelan scale. Only Grade 1 (more than 75% bony fill) cases were considered successful. Early unilateral SABG had a success rate of 90% while late unilateral SABG rate was 80%. The overall success rate of the unilateral SABG (85%) was higher than the rate for the bilateral cases (56%). Our findings support the conclusion that the outcome of early SABG is superior to late SABG. The overall success rate of SABG sample (74%) compared relatively well with other published results.  相似文献   
992.
993.
994.
Diabetes.     
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995.
最近对口腔鳞癌的治疗观念发生了变化,其中包括新辅助治疗(术前化疗、手术、术后放疗)及辅助治疗(手术、术后放疗)。该文旨在对2种治疗方法对患者长期生存率的影响进行了比较。方法:将患者分为2组,一组74例,行新辅助治疗,另一组54例行辅助治疗。99例为Ⅲ-Ⅳ期的患者,  相似文献   
996.
997.
The transverse dentofacial morphology of 36 children with bilateral cleft lip, alveolus and palate was studied by means of a frontal proportional cephalometric analysis at the ages of three, eight and twelve years. Comparison of the variables of the cleft group was made with the normal dimensions as obtained from the Bolton cephalometric templates. The results indicated that the BCLP group presented characteristics and significant differences from the normal in the dimensions of the nasal septum width and the mandibular intergonial width as they are both related to the interorbital width, the maxillary intermolar width as it is related to the mandibular intermolar width and the maxillary width as it is related to the mandibular intergonial width at all three ages. The maxillary base and intermolar widths, although significantly different at the ages of three and eight years, showed no significant deviation from normality at the age of twelve years. Following orthodontic treatment between the ages of seven to twelve years, the maxillary intermolar width of the treated subgroup was significantly larger than in the untreated subjects.  相似文献   
998.
Zusammenfassung Für die Okklusion und den Gelenkbereich sind Zuordnungsnormen existent. Dies ist im Seitenzahnbereich die Höcker-Fossa-Relation, im Frontzahnbereich die Zuordnung der Unterkiefer-Inzisalkanten zu der Nullpunktlinie der palatinalen Konkavitäten im Oberkiefer und im Gelenkbereich die physiologische Kondylenposition. Letztere läßt sich im Pantogramm durch den Wendepunkt der von der Achse bei sagittaler Grenzführung gezeichneten Kurve präzisieren, in Übertragung aber auch im Röntgenbild ermitteln.Ziel der kieferorthopädischen Behandlung sollte die physiologische Zuordnung von Seitenzähnen, Frontzähnen und Gelenken sein. Das vorgestellte Funktionsmodell gibt Hilfestellungen bei der Behandlung auf ein funktionelles Optimum hin.Die Gelenke sind bei der Behandlung wie ein eigenes terminales Okklusionspaar zu betrachten. Ihre korrekte Einstellung läßt sich bisher nur durch Röntgenbilder und durch die pantographische Aufzeichnung darstellen.
Summary We are convinced that there is a relation between the occlusion and the temporomandibular joint. In the molar region the correlation is known as the cusp-fossa relationship. In the incisor region the corresponding structures are the mandibular incisor tips and the palatal concavities of the upper incisors. We have designated the correlation in the TMJ-region as the physiological condyle position, which can be identified in the sagittal pantogram by the turning point of the traced sigmoid curve. Similarly this position can be shown by our method on the TMJ-radiograph.The aim of orthodontic treatment should be a physiological positioning of molars, incisors and joints. The functional model presented above can render assistance in achieving a functional optimum in treatment.The temporomandibular joints must be regarded in treatment as additional occluding points. Up to now their correct positioning has been visible only through the use of TMJ-radiographs and pantographic tracings.

Résumé Il existe des normes structurelles correspondantes entre l'occlusion et l'articulation temporomandibulaire; à savoir dans les zones latérales d'arcades la relation cuspide-sillon, dans le segment antérieur l'arête des incisives inférieures glissant le long des faces palatines des incisives supérieures jusqu'à la ligne d'arrêt et au niveau de l'articulation la position physiologique du condyle. Cette corrélation s'établit dans le plan sagittal du pantogramme par l'existence d'un point tournant du tracé sigmoïde; on peut transposer cette position dans l'image radiographique.Le but d'un traitement orthodontique est de coordonner physiologiquement les segments latéraux et antérieur d'arcades et l'articulation temporo-mandibulaire. Des moulages fonctionnels préétablis nous aident à obtenir la meilleure fonction au cours du traitement.On doit considérer la double articulation temporo-mandibulaire comme une occlusion finale. Seuls la radiologie et les tracés pantographiques permettent de juger de la position correcte des condyles dans leurs fosses glénoïdes.


In memoriam Herrn Prof. Dr.G. Müller von seinen ehemaligen Schülern und Mitarbeitern.  相似文献   
999.
When a certain bite force is applied during unilateral chewing, the combination of jaw elevator muscle activities is different than when a comparable force is applied in unilateral isometric biting, e.g. on a force transducer. Masticatory peak force is generated in a nearly isometric phase of the chewing cycle, with a jaw gape of about 1 mm. In contrast, peak force in isometric biting on force measuring equipment usually induces jaw gapes of 6 mm or even more. Therefore, we tested the hypothesis that the jaw gape influences relative activation of elevator muscles in unilateral isometric biting. We further examined whether such influence could explain the different activity combinations of chewing and isometric biting. In thirty asymptomatic males, masseter and temporalis activities were recorded during intermittent isometric biting with jaw gapes of 6, 5, 3, 2 and 1 mm and during unilateral chewing. Activity combinations were described by working/balancing ratios and by temporalis/masseter ratios. With decreasing jaw gape the working/balancing ratio of the posterior temporalis decreased (P < 0.002) while that of the masseter increased (P < 0.001). Likewise, the temporalis/masseter ratio on the balancing side increased (P < 0.001). With decreasing jaw gape, activity ratios of isometric biting approached ratios of chewing. We conclude that: (i) relative jaw muscle activation in isometric biting depends on the jaw gape, (ii) relative muscle activation in chewing resembles relative activation of isometric biting with a small 'chewing-like' gape. This suggests that characteristic activity combinations in chewing are mainly a result of the approximately isometric contraction during the slow closing phase of the chewing cycle.  相似文献   
1000.
The objective of this study was to evaluate the role of collagen membrane and Bio-Oss coverage in healing of an onlay graft to the mandible. Twelve adult sheep each received an onlay bone graft (experiment 1), bone graft+Bio-Gide (experiment 2), and bone graft+Bio-Oss/Bio-Gide (experiment 3) on the lateral surface of the mandible. The animals were euthanized at 4, 8, 12 or 16 weeks after surgery, and findings were analysed by routine microscopy and immunohistochemistry for proliferation (Ki67) and apoptotic (Caspase-3) markers. Grafts were fully incorporated in all specimens. Pronounced resorption was observed in experiment 1. Minimal loss of graft volume was seen in experiment 2 specimens without membrane displacement. A remarkable increase in the augmented region of the mandible was observed in experiment 3. A high number of osteoclasts were expressed within the grafts during the early healing period, and thereafter declined markedly. Osteoblasts within the grafts expressed a moderate level of Ki67 at 8 weeks, which thereafter declined markedly. The strongest expression of Caspase-3 on the bone surface was observed after 16 weeks. In conclusion, the effect of collagen membrane coverage on bone graft volume maintenance was dependent on membrane stability during healing. An autogenous bone graft covered with Bio-Oss particles resulted in a remarkable increase in augmented lateral surface of the mandible. The late stage of bone graft healing was associated with a high apoptotic induction pathway of osteoblasts lining the surfaces of the new bone, demonstrated by strong positive Caspase-3 immunoreactivity.  相似文献   
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