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Base Angle (base + angle)
Kinds of Base Angle Selected AbstractsCraniofacial morphology in patients with hypophosphataemic vitamin-D-resistant rickets: a cephalometric studyJOURNAL OF ORAL REHABILITATION, Issue 7 2009S. H. AL-JUNDI Summary, Hypophosphataemic vitamin-D-resistant rickets (HVDRR) is a hereditary disease mainly transmitted as an X-linked dominant trait and characterized by certain general clinical signs (Filho HM, de Castro LC, Damiani D. Arq Bras Endocrinol Metab. 2006;50:802). In literature, only one study had been published in 1965 on the cephalometric findings in patients with HVDRR (Marks SC, Lindahl RL, Bawden JW. J Dent Child. 1965;32:259). This is the first detailed study on craniofacial characteristics of patients with HVDRR in the dental literature. The aim of this study was to determine the effect of HVDRR on the parameters of the craniofacial skeleton of young Jordanian patients using cephalometric analysis. Lateral cephalometric radiographs were made for 22 Jordanian children (aged 2,16 years) diagnosed with HVDRR. The cephalometeric parameters of HVDRR group were compared with those of normal control group matched for gender and chronological age using paired t -test. The HVDRR group had a significant increase in the SNBa angle (P < 0·01); as well as reduced anterior cranial base length (P = 0·01), reduced maxillary length, corpus mandibular length and mandibular height (P = 0·01, 0·04 and 0·008 respectively). The cranial base and gonial angles were significantly increased in diseased individual, but the SNA and ANB angles were significantly reduced (P = 0·018 and 0·000 respectively). The angulation of the lower incisor to mandibular plane was also significantly reduced in the diseased group compared with Jordanian norm (P = 0·004). Patients with HVDRR have deficiency in the anterior cranial base length, ramus height and cranial base angle. Patients with HVDRR also have class III skeletal relationship. [source] Morphological plasticity of Parrotia persica leaves in eastern Hyrcanian forests (Iran) is related to altitudeNORDIC JOURNAL OF BOTANY, Issue 3 2010Hamed Yosefzadeh Variation in leaf characters of Parrotia persica in relation to their position in the canopy along an altitudinal gradient were studied. Genetic and phenotypic characters make P. persica one of the most noteworthy plants in the five floristic regions of Iran. It is an endemic species of the Hyrcanian forests, and occurs naturally from sea level to over 900 m a.s.l. on the north side of the Mountain Ranges of Alborz, northern Iran. There was a significant effect of altitude only on few leaf features [width of lamina, base angle (internal angle of lamina), number of pair vein (number of principal veins of lamina) of leaf, top and end of leaf figure]. Among different geographical sides of the crown, there was no significant difference in the plasticity of leaf features, but leaf figure (both top of leaf figure and end of leaf figure) showed the lowest plasticity among the different leaf characters. Of all characters measured, the lowest plasticity among the three populations was found for base angle and number of vein pairs. A PCA analysis showed that leaf petiole and maximum width of lamina in 0.9 of its length, together with leaf figure and width of lamina, accounted for the greatest variation in difference of populations. [source] Cervical column morphology in patients with skeletal open biteORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 1 2008L Sonnesen Structured Abstract Authors,,, Sonnesen L, Kjær I Objectives,,, To examine and compare the cervical column morphology in adult patients with skeletal open bite with the cervical column morphology of an adult control group with neutral occlusion and normal craniofacial morphology. Design,,, A retrospective case,control study. Setting and Sample Population,,, Thirty-eight open bite patients, 27 women, aged 17,39 years, and 11 males, aged 18,40 years were compared with 21 controls, 15 females, aged 23,40 years, and six males aged 25,44 years from profile radiographs. Outcome measure,,, From each individual a visual assessment of the cervical column and angular measurements of the craniofacial dimensions were performed on profile radiographs. Results,,, In the open bite group 42.1% had cervical column body fusion, and 13.2% had posterior arch deficiency. The fusion always occurred between C2 and C3. Cervical column deviations occurred significantly more often in the open bite group compared with the control group (p < 0.05). Associations were found between fusions of the cervical column and maxillary retrognathia (p < 0.05), large maxillary inclination (p < 0.05) and large cranial base angle (p < 0.05). Associations were also found between posterior arch deficiency and maxillary retrognathia (p < 0.05) and cranial base angle (p < 0.05). The craniofacial parameter most important for the fusions and posterior arch deficiency was the maxillary retrognathia (p < 0.01, R,2 = 0.20; p < 0.05, R,2 = 0.26, respectively). Conclusion,,, New associations between skeletal open bite and cervical column deviations are described. It is suggested that this knowledge is incorporated in future diagnostic and orthodontic treatment planning. [source] An interspecific analysis of relative jaw-joint height in primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Brooke A. Armfield Abstract Jaw-joint height (JJH) above the occlusal plane is thought to be influenced by cranial base angle (CBA) and facial angulation during growth. To better understand how JJH relates to midline craniofacial form, we test the hypothesis that relative increases in JJH are correlated with increasing CBA flexion and facial kyphosis (i.e., ventral bending) across primates. We compared JJH above the occlusal plane to CBA and the angle of facial kyphosis (AFK) across adults from 82 species. JJH scales with positive allometry relative to a skull geometric mean in anthropoids and most likely strepsirrhines. Anthropoid regressions for JJH are elevated above strepsirrhines, whereas catarrhines exhibit a higher slope than platyrrhines. Semipartial correlations between relative JJH and both CBA and AFK show no association across a small strepsirrhine sample, limited associations among catarrhines and anthropoids, but strong correlations in platyrrhines. Contrary to our hypothesis, however, increases in relative JJH are correlated with relatively less flexed basicrania and more airorhynch faces (i.e., reduced ventral bending) in platyrrhines. The mosaic pattern of relationships involving JJH across primate clades points to multiple influences on JJH across primates. In clades showing little association with basicranial and facial angles, such as strepsirrhines, the potential morphological independence of JJH may facilitate a relative freedom for evolutionary changes related to masticatory function. Finally, failure to associate relative JJH and basicranial flexion in most clades suggests that the relatively taller JJH and more flexed basicrania of anthropoids compared to strepsirrhines may have evolved as an isolated event during the origin of anthropoids. Am J Phys Anthropol 142:519,530, 2010. © 2010 Wiley-Liss, Inc. [source] Effect of the Equipment Configuration and Operating Conditions on Process Performance and on Physical Characteristics of the Product During Coating in Spouted BedTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2004M. C. P. Publio Abstract The effects of the configuration and operating conditions on the performance of the spouted bed tablet coating process have been studied. The configuration parameters analyzed were the ratio between the draft tube diameter and the inlet orifice diameter, dT/di, and the conical base angle, ,. To analyze the equipment performance the adhesion coefficient, ,, and the increase rate of the tablet mass, K1, were measured as a function of the mass flow rate of the coating material, Ws, of the ratio between the mass feed flow rate of coating suspension relative to mass feed flow rate of the spouting gas, W*s/W*g, of the air flow rate relative to minimum spouting, Q/Qms, and of the feed flow rate of atomising air, Wat. Procedures for the evaluation of the growth kinetics and for measuring the product uniformity are presented. On a étudié les effets de la configuration et des conditions opératoires sur la performance du procédé d'enrobage de tablettes en lit jaillissant. Les paramètres de configuration étudiés sont le rapport entre le diamètre du tube d'aspiration et le diamètre de l'orifice d'entrée, dT/di, et l'angle de base conique, ,. Pour analyser la performance de l'équipement, le coefficient d'adhésion, ,, et la vitesse d'augmentation du poids de la tablette, K1, ont été mesurés en fonction du débit massique du matériau d'enrobage, Ws, du rapport entre le débit d'alimentation massique de la suspension d'enrobage et le débit d'alimentation massique du gaz jaillissant, W*s/W*g, du débit d'air et du jaillissement minimal, Q/Qms, et du débit d'alimentation de l'air d'atomisation, Wat. On présente des méthodes pour évaluer les cinétiques de croissance et mesurer l'uniformité de produit. [source] Spondylolysis in a pre-contact San Francisco Bay population: behavioural and anatomical sex differencesINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2009E. Weiss Abstract Spondylolysis refers to a separation of the spinal body from the arch. Researchers have documented that these fractures occur due to stresses related to activities involving the lower limb and back. Spondylolysis in sacral and lumbar vertebrae of 146 (66 males, 66 females, 14 indeterminates) California Amerinds were examined to determine whether sex differences were present. Sacral anatomy (i.e. sacralisation and lumbarisation, sacral base angles, and superior facet morphology) was analysed in relation to spondylolysis and sex, to explore whether sex differences could be better explained through activity patterns or anatomical variation. Spondylolysis afflicted 24 individuals (16.4%). Males had more than twice the rate of spondylolysis than did females (26% and 11%, respectively). Activity patterns, such as thrusting and throwing shafted obsidian points, could explain the sex differences. Males were most frequently buried with obsidian point artefacts, whereas females were buried with mortar and pestles. For sacral anatomy, only males had lumbarisation, and all other anatomical variation had no significant sex differences. Lumbarisation related to spondylolysis in males. In this study, sacral anatomical variation could not fully account for sex differences in spondylolysis; activity patterns provided a better explanation. Nonetheless, anatomical variation may predispose males to spondylolysis, or spondylolysis may affect sacral anatomy. Copyright © 2008 John Wiley & Sons, Ltd. [source] Craniofacial cephalometric morphology in children with CATCH 22 syndromeORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2006A Heliövaara Structured abstract Authors ,, Heliövaara A, Hurmerinta K Objectives ,, To evaluate cephalometrically the craniofacial, pharyngeal and cervical morphology in children with CATCH 22, and to compare and quantify the findings with age- and sex-matched controls. Design ,, A retrospective case,control study. Setting and Sample Population , Forty-one children (20 girls) with CATCH 22 were compared with age- and sex-matched controls from lateral cephalograms taken at the mean age of 8.5 years (range 5.8,12.9). The deletion of 22q11 was verified by fluorescence in situ hybridization techniques. Thirteen of the children with CATCH 22 had palatal clefts. Outcome measure ,, Linear and angular measurements were obtained from lateral cephalograms. A Student's t -test and a paired Student's t -test were used in the statistical analysis. Standard deviation scores (SDS) were calculated to quantify the variation. Results ,, Children with CATCH 22 had obtuse cranial base angles and long anterior cranial bases. Their faces were long with increased facial convexity. The maxillae were long but both jaws were retrognathic and the lower jaws posteriorly diverged. The pharynges were wide in the nasopharyngeal area and narrow in the hypopharyngeal area. The development of the hyoid bones was delayed, and hyoid bone and atlas lengths were reduced. The morphology of the children with CATCH 22 with and without a palatal cleft was similar. Despite several statistically significant differences between the children with CATCH 22 and the controls, the SDS did not exceed ±2 for any of the measurements. Conclusion ,, Children with CATCH 22 have several minor distinctive morphological features in the craniofacial, pharyngeal, and cervical areas. [source] A cranial base of Australopithecus robustus from the hanging remnant of Swartkrans, South AfricaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2006Darryl J. de Ruiter Abstract SKW 18, a partial hominin cranium recovered from the site of Swartkrans, South Africa, in 1968 is described. It is derived from ex situ breccia of the Hanging Remnant of Member 1, dated to approximately 1.5,1.8 Mya. Although partially encased in breccia, it was refit to the facial fragment SK 52 (Clarke 1977 The Cranium of the Swartkrans Hominid SK 847 and Its Relevance to Human Origins, Ph.D. dissertation, University of the Witwatersrand, Johannesburg), producing the composite cranium SKW 18/SK 52. Subsequent preparation revealed the most complete cranial base attributable to the species Australopithecus robustus. SKW 18 suffered weathering and slight postdepositional distortion, but retains considerable anatomical detail. The composite cranium most likely represents a large, subadult male, based on the incomplete fusion of the spheno-occipital synchondrosis; unerupted third molar; pronounced development of muscular insertions; and large teeth. Cranial base measures of SKW 18 expand the range of values previously recorded for A. robustus. SKW 18 provides information on anatomical features not previously visible in this taxon, and expands our knowledge of morphological variability recognizable in the cranial base. Morphological heterogeneity in the development of the prevertebral and nuchal muscular insertions is likely the result of sexual dimorphism in A. robustus, while differences in cranial base angles and the development of the occipital/marginal sinus drainage system cannot be attributed to size dimorphism. Am J Phys Anthropol, 2006. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||