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Palatine Bone (palatine + bone)
Selected AbstractsAnatomical study of the pyramidal process of the palatine bone in relation to implant placement in the posterior maxillaJOURNAL OF ORAL REHABILITATION, Issue 2 2001S. P. Lee The placement of dental implants in the molar region of the maxilla is often difficult because of insufficient bone volume and the inferior bone quality. In order to avoid these limitations, the pillar of bone, which is composed of the maxillary tuberosity, the pyramidal process of the palatine bone and the pterygoid process of the sphenoid bone, was introduced for implant placement. In fact, the pyramidal process is the posterior structure where implants are placed but until now, there is no available data of the size or shape of the pyramidal process. Therefore, we measured the height, anteroposterior distance and mediolateral distance of the pyramidal process and observed the shape of lateral and posterior surfaces of the pyramidal process of 54 Korean edentulous dry skulls in this study. The height was 13·1 mm (male: 13·6 mm, female: 12·4 mm). The anteroposterior distance was 6·5 mm (male: 6·7 mm, female: 6·1 mm). The mediolateral distance was 9·5 mm (male: 9·9 mm, female: 9·0 mm). The most common type was the right-angled triangle in the lateral surface (44·4%) and in the posterior surface (66·7%). There was no statistical significance between the male and the female in all items (P > 0·05). These results provide anatomical features in relation to placement of dental implants in the molar region of the maxilla and would be useful in treatment planning of partially or completely edentulous patients. [source] A quantitative analysis of the Eutherian orbit: correlations with masticatory apparatusBIOLOGICAL REVIEWS, Issue 1 2008Philip G. Cox Abstract The mammalian orbit, or eye-socket, is a highly plastic region of the skull. It comprises between seven and nine bones, all of which vary widely in their contribution to this region among the different mammalian orders and families. It is hypothesised that the structure of the mammalian orbit is principally influenced by the forces generated by the jaw-closing musculature. In order to quantify the orbit, fourteen linear, angular and area measurements were taken from 84 species of placental mammals using a Microscribe-3D digitiser. The results were then analysed using principal components analysis. The results of the multivariate analysis on untransformed data showed a clear division of the mammalian taxa into temporalis-dominant forms and masseter-dominant forms. This correlation between orbital structure and masticatory musculature was reinforced by results from the size-corrected data, which showed a separation of the taxa into the three specialised feeding types proposed by Turnbull (1970): i.e. ,carnivore-shear', ,ungulate-grinding' and ,rodent-gnawing'. Moreover, within the rodents there was a clear distinction between species in which the masseter is highly developed and those in which the temporalis has more prominence. These results were reinforced by analysis of variance which showed significant differences in the relative orbital areas of certain bones between temporalis-dominant and masseter-dominant taxa. Subsequent cluster analysis suggested that most of the variables could be grouped into three assemblages: those associated with the length of the rostrum; those associated with the width of the skull; and those associated with the relative size of the orbit and the shape of the face. However, the relative area of the palatine bone showed weak correlations with the other variables and did not fit into any group. Overall the relative area of the palatine was most closely correlated with feeding type, and this measure that appeared to be most strongly associated with the arrangement of the masticatory musculature. These results give a strong indication that, although orbital structure is in part determined by the relative size and orientation of the orbits, the forces generated by the muscles of mastication also have a large effect. [source] Role of annexin 1 gene expression in mouse craniofacial bone developmentBIRTH DEFECTS RESEARCH, Issue 7 2007Amilcar Sabino Damazo Abstract BACKGROUND: Annexin 1 is a 37-kDa protein that has complex intra- and extracellular effects. To discover whether the absence of this protein alters bone development, we monitored this event in the annexin-A1 null mice in comparison with littermate wild-type controls. METHODS: Radiographic and densitometry methods were used for the assessment of bone in annexin-A1 null mice at a gross level. We used whole-skeleton staining, histological analysis, and Western blotting techniques to monitor changes at the tissue and cellular levels. RESULTS: There were no gross differences in the appendicular skeleton between the genotypes, but an anomalous development of the skull was observed in the annexin-A1 null mice. This was characterized in the newborn annexin-A1 null animals by a delayed intramembranous ossification of the skull, incomplete fusion of the interfrontal suture and palatine bone, and the presence of an abnormal suture structure. The annexin-A1 gene was shown to be active in osteocytes during this phase and COX-2 was abundantly expressed in cartilage and bone taken from annexin-A1 null mice. CONCLUSIONS: Expression of the annexin-A1 gene is important for the normal development of the skull in mice, possibly through the regulation of osteoblast differentiation and a secondary effect on the expression of components of the cPLA2-COX-2 system. Birth Defects Research (Part A), 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||