微型钛板联合颌间牵引钉内固定术治疗颌骨骨折疗效观察

目的:探讨微型钛板联合颌间牵引钉内固定术治疗颌骨骨折的临床效果及其在临床的安全性。方法:随机选取颌骨骨折患者共60例,将上述患者随机平均分成对照组与观察组。分别给予与单纯微型钛板坚固内固定治疗和微型钛板联合颌间牵引钉内固定术治疗方法。分析比较这两组患者4周内的临床治疗效果及安全性。结果:术后4周两组间临床治疗效果比较显示:采取微型钛板联合颌间牵引钉内固定术治疗的观察组治疗效果明显好于给予单纯微型钛板坚固内固定治疗的对照组。观察组总有效率为87%,对照组总有效率为53.3%,差异有统计学意义(P0.05).两组手术过程均顺利实施,患者术后均无严重并发症发生,术后恢复情况较好,经比较两组术后不良反应的差异无统计学意义(P0.05)。结论:微型钛板联合颌间牵引钉内固定术是治疗颌骨多发骨折有效安全方法。     

The form of the talus in some higher primates: a multivariate study

Sixteen measurements of the talus have been taken on 334 tali of a total of eleven primate groups and several additional single individual specimens. Multivariate morphometric (canonical and generalized distance) analyses of these data in extant higher primates are presented and used to define the relative morphological positions of fossils of the genera Proconsul and Limnopithecus, of individual specimens from Kromdraai, Olduvai and Kiik-Koba (Homo neanderthalensis), and a group of specimens of Bronze Age man from Jericho. Following preliminary studies the ultimate analysis suggests that the various extant arboreal primates examined fall within an envelope that is defined by Macaca together with various other Old World monkeys and extending in different directions to the extreme genera (a) Pongo, (b) Hylobates and (c) Ateles. This separation is thus one which defines generally quadrupedal monkeys and separates the various extreme arboreal locomotor modes of (a) acrobatic climbing and hanging, (b) richochetal brachiation and (c) prehensile-tailed arm-swinging and hanging, respectively. Man and the African apes are well separated both from each other and from this spectrum of arboreally adapted genera. Bronze Age man from Jericho and Neandertal man from Kiik-Koba lie relatively close to the position for modern man although significantly separated from him. Limnopithecus, Proconsul, and the specimens from Kromdraai and Olduvai all lie within the envelope of arboreal species and specifically rather close to, although significantly different from, the orang-utan; they differ markedly from both man and the African apes. The possibility exists that the resemblances of Proconsul and Limnopithecus relate to arboreal habitus in these species. The findings for the specimens from Kromdraai and Olduvai suggest either that the morphological resemblances to arboreal forms relate to a previous arboreal history for these species, or that bipedality is much less advanced or uniquely different from that displayed by Homo. It is not inconceivable that both conditions might apply.     

Some African fossil foot bones: a note on the interpolation of fossils into a matrix of extant species

Certain fossil foot bones (a terminal toe phalanx from Olduvai, specimens of tali from Spy, Skhūl, Olduvai, Kromdraai, Songhor and Rusinga) have been investigated by other workers using the multivariate statistical approach. The conclusions of their studies have, in the main, been based upon examination of early canonical variates alone. It is demonstrated here that if the full analyses (generalized distances) are taken into account, then almost exactly opposite conclusions obtain. The terminal toe phalanx from Olduvai is widely different from those of modern men; the Neandertal tali differ more from modern human bones than previously realized; the specimens from Olduvai, Kromdraai, Songhor and Rusinga are all completely dissimilar from both African ape and modern human tali.     

Cusp size, sexual dimorphism, and heritability of cusp size in twins.

Overall measures of mandibular molars reflect the combined size contributions of the component cusps and ridges. Until now, the size hierarchy of primary and permanent mandibular molar cusps remained unclear. This paper utilizes the relative plane surface areas (basal area dimensions) of the individual molar cusps, as assays of cusp size to demonstrate cusp size variations within populations, antimere cuspal variations, sexual dimorphism, and, the heritability of cusp size. Duplicate dental casts from 199 pairs of like-sexed twins provide the raw dats. Defined anatomic landmarks on the occlusal surfaces were reduced to X-Y rectangular coordinates prior to the computation of the basal areas dimensions. The results establish a cusp size hierarchy specific for molar type, i.e., five-cusped molars with a distal fovea and distal marginal ridge (5fd), five-cusped molars without a distal fovea and without a distal marginal ridge (5o), and four-cusped molars (4c). Sexual dimorphism in cusp size is apparent in 5fd molar cusped but not in 5o molar cusps. However, males have a significantly higher frequency of 5fd molars. Females have a higher frequency of smaller 5o and 4c molars which have fewer crown components. Moreover, female 5o molars have cusps as large as or larger than 5o male molor cusps. Right-side-left-side differences exist between antimere cusps based on relatively low correlations. The mirroring of molor types occurs infrequently. When observed, most intrapair differences for cusp size, using F-ratios, indicate a low component of hereditary variability.     

Sclerotic plates or circumorbital bones in early jawed fishes?

Abstract: Circumorbital dermal bones are found in most groups of early vertebrates that have dermal bony plates on the head. Taxonomic distribution of dermal sclerotic plates on the eye itself is less clear, partly because the eyeball is rarely preserved and sometimes because sclerotic bones have been misinterpreted as circumorbital bones. Based on the examination of climatiid Climatius plus mesacanthid, cheiracanthid and acanthodid acanthodiform acanthodians, we conclude that most, if not all, acanthodiforms and climatiids had sclerotic rings. Presence and number of these elements should be included as a character in phylogenetic analyses of early jawed vertebrates.     

Mandibular movement patterns relative to food types in common tree shrews (Tupaia glis)

Although common tree shrews have long been considered a model system for early eutherian mastication, little information on mandibular movement patterns relative to specific food types has been reported. Detailed analysis of mandibular movement patterns when related to resulting attrition facets may permit more accurate extrapolations regarding the dietary habits of primitive mammals. Marker beads were sewn to chins of five animals that were placed in a restraint system and filmed while they fully masticated mealworm larvae and standardized pieces of banana, almond, and commercial cat chow. These sequences were divided into early, middle, and late thirds of food reduction. Mandibular positions from both frontal and lateral perspectives were digitized frame by frame to yield plots of orbits in three dimensions as well as graphic display of displacements, velocities, and accelerations. Plot coordinates were averaged to generate composite orbital shapes. Significant (p < 0.01) findings included: (1) shortest orbital durations and greatest peak closing velocities and accelerations in early third of reduction; (2) smallest maximum gape, smallest maximum lateral excursion from midline, and longest duration of powerstroke relative to orbital duration in late third of reduction; (3) shortest orbital durations and smallest maximum gape during mastication of chow; (4) greatest maximum lateral excursion during mastication of mealworm larvae; and (5) smallest peak closing accelerations during mastication of banana. Significant differences were also found among subjects for all parameters examined. Capacity for complex jaw movement may have been critical for allowing primitive molars to be used for trituration of a variety of food types, and may have preceded evolution of more specialized molar forms.     

Mandibular torus morphology

The morphology of the mandibular torus was examined, and comparisons were made between a Medieval Norse skeletal population from Greenland and a 14th to 17th century Greenland Eskimo skeletal series. Three parameters were analyzed: degree of development (on a 4-point scale), position and length, and surface morphology according to the number of knobs, or lobuli. It was found that the Eskimos have a high frequency of weakly developed tori and no cases of the extreme development, while over 20% of the Norsemen had tori in the “extreme” category. The Norse torus was generally found to be longer than that of the Eskimos, and both groups exhibited a slight asymmetry between the sides, the torus on the left side tending to be longer and more forward in position than the right. A great difference was found in surface morphology. The Norse torus is in general very irregular, while the Eskimo torus is rather smooth. These differences are believed to be genetically determined.