红条毛肤石鳖齿舌主侧齿中铁还原酶分布及与生物矿化的关系

以红条毛肤石鳖Acanthochiton rubrolineatus(Lischke)齿舌为材料,通过切片和酶组织化学技术,在光镜和电镜下对齿舌主侧齿的微结构及高铁还原酶的存在进行观察,从微观角度了解齿舌主侧齿齿尖的矿化机理。结果显示,成熟主侧齿由齿尖和齿基组成。齿尖结构由外至内分为三层,最外层为磁铁矿层,前后齿面磁铁矿层的厚度不等,后齿面约50μm,前齿面约5-10μm。向内依次为棕红色的纤铁矿层,厚约10μm,及略显黄色的有机基质层,有机基质层占据着齿尖内部的大部分结构。高分辨透射电镜下显示磁铁矿由条状四氧化三铁颗粒组成,长约2-3μm,宽约100-150nm。齿舌的矿化是一个连续过程,不同部段处于不同的矿化阶段,齿舌囊上皮细胞沿囊腔分布,并形成齿片。未矿化的新生主侧齿齿尖中存在由有机基质构成的网状结构。随矿化的进行,有机基质内出现矿物颗粒。初始矿化的齿尖外表面有一个细胞微突层,微突的另一端为囊上皮细胞,矿物质经由微突层达齿尖并沉积于有机基质中,齿尖随之矿化并成熟。初始矿化齿尖的外围有大量的三价铁化物颗粒,稍成熟的齿尖外围同时还出现二价铁化物。新生或初始矿化主侧齿齿尖外围的囊上皮细胞中有大量球形类似于铁蛋白聚集体的内容物,直径0.6-0.8μm,球体由膜包围。齿舌囊上皮组织中存在三价高铁还原酶,此酶分布于上皮细胞的膜表面,可能与齿尖表面磁铁矿的生成有一定的关系。       

Structural Organisation of the Cusps of the Radular Teeth of the Chiton Plaxiphora albida

Abstract The structure, morphology and organisation of the cusps of the major lateral radula teeth of the chiton Plaxiphora albida have been examined using light, transmission and scanning electron microscopy, together with energy dispersive X-ray analysis and Mössbauer spectroscopy. In this chiton species, both the anterior and posterior surfaces of the major lateral teeth are composed of magnetite, which is indicated to be non-stoichiometric and associated with some maghemite, together with small amounts of phosphorus and silicon. This outer layer surrounds an inner core region of the tooth, which only reaches the surface through a small window zone on the anterior surface and which contains large amounts of iron and phosphorus presumably in the form of iron(III) phosphate. The organic matrix, on which the teeth are constructed, consists of a zone of densely packed fine fibres at the surface of the tooth, underlain by larger fibres which become sparser deeper into the cusp. The core region is characterized by the presence of densely packed short fibres. In contrast to the situation found in most other species of chiton, large fibres of the organic matrix extend throughout the region of magnetite mineralization, leading to the suggestion that the matrix exerts more control over the mineralization of magnetite than has previously been thought.     

Characterization of the calcium biomineral in the radular teeth of Chiton pelliserpentis

The radula in a group of molluscan invertebrates, the chitons (Polyplacophora), is a ribbon-like apparatus used for feeding and which bears a series of distinctive mineralized teeth called the major lateral teeth. While some chiton species deposit only iron biominerals in these teeth, many others deposit both iron and calcium. In this study, the calcium biomineral in the teeth of one of the latter types of species, the Australian east-coast chiton, Chiton pelliserpentis, has been isolated and examined for the first time. Spectroscopic and crystallographic techniques have identified the biomineral as a carbonate-substituted apatite with significant fluoride substitution also likely. Fourier-transform infrared and laser Raman spectroscopy indicated that the carbonate content was less than that of either bovine tibia cortical bone or human tooth enamel. X-ray diffraction analysis showed the biomineral to be poorly crystalline due to small crystal size and appreciable anionic substitution. The lattice parameters were calculated to be a=9.382?Å and c=6.883?Å, which are suggestive of a fluorapatite material. It is postulated that structural and biochemical differences in the tooth organic matrix of different chiton species will ultimately determine if the teeth become partly calcified or iron mineralized only.     

A new biomineral identified in the cores of teeth from the chiton <Emphasis Type="Italic"> Plaxiphora albida</Emphasis>

The hydrated iron(III) oxide limonite is reported for the first time as a biomineral. In situ laser Raman spectra of the tooth cores from major lateral teeth of the chiton Plaxiphora albida are compared with those of synthetic and mineral iron phosphates and iron oxides. Raman spectra measured on iron phosphate and iron oxide standard materials are shown to be easily distinguishable from one another. The central tooth cores of mature P. albida teeth do not show any evidence for the presence of a separate iron phosphate mineral. Rather, in each tooth a narrow band of the hydrated iron(III) oxide limonite is shown to separate the magnetite of the tooth surface from a central core region comprising both lepidocrocite and limonite. The high concentration of phosphorus in P. albida tooth cores, previously observed by energy dispersive spectroscopy, is not associated with a separate iron phosphate mineral, indicating that this element may be adsorbed onto the surface of the iron oxide minerals present. The failure to detect a separate iron(III) phosphate is discussed with reference to other chiton species that display high levels of iron and phosphorus in the cores of their mature major lateral teeth.     

嫁[虫戚]的齿舌带及其齿片的形态差异分析

在光镜和电镜下对嫁[虫戚]（Cellana toreuma）的齿舌形态进行观察研究。嫁[虫戚]的齿舌带每1横列具有2枚侧齿和2枚缘齿,缺乏中央齿,齿式为1.1.0.1.1。齿舌带前端弯曲,齿片排列松散且存在明显的磨损现象;中段齿片排列紧密、整齐;后端齿片无色且宽度有略微的缩小。侧齿呈镰刀型,具1个齿尖,基部呈三角形且具突起,尖齿部分细长;缘齿具3个齿尖,第2尖齿靠近第3尖齿。采用多个比例参数来比较嫁齿舌带及其前、中、后3段上的齿片形态,发现嫁齿舌带前、中、后3段各比例参数的值存在一定的关系,即中段大于前段、中段大于后段。     

Three-dimensional microarchitecture of the plates (primary, secondary, and carinar process) in the developing tooth of Lytechinus variegatus revealed by synchrotron X-ray absorption microtomography (microCT)

This paper reports the first noninvasive, volumetric study of entire cross-sections of a sea urchin tooth in which the individual calcite structural elements could be resolved. Two cross-sectionally intact fragments of a Lytechinus variegatus tooth were studied with synchrotron microCT (microcomputed tomography) with 1.66 microm voxels (volume elements). These fragments were from the plumula, that is the tooth zone with rapidly increasing levels of mineral; one fragment was from a position aboral of where the keel developed and the second was from the zone where the keel was developing. The primary plates, secondary plates, carinar process plates, prisms, and elements of the lamellar-needle complex were resolved. Comparison of the microCT data with optical micrographs of stained thin sections confirmed the identifications and measured dimensions of the characteristic microarchitectural features. The interplay of reinforcing structures (plates and prisms) was more clearly revealed in the volumetric numerical data sets than in single or sequential slices. While it is well known that the primary plates and prisms in camarodont teeth are situated to improve resistance to bending (which can be termed primary bending), the data presented provide a new understanding of the mechanical role of the carinar process plates, that is, a geometry consistent with that required in the keel to resist lateral or transverse bending of the tooth about a second axis. The increase in robustness of teeth incorporating lateral keel reinforcement suggests that the relative development of carinar processes (toward a geometry similar to that of L. variegatus) is a character which can be used to infer which sea urchins among the stirodonts are most primitive and among the camarodonts which are more primitive.     

The mineralization and hardness of the radular teeth of the limpet Patella vulgata L.

Summary A study of the Patella vulgata radula has been made using: the scanning electron microscope in its normal and compositional contrast modes of operation, the electron microprobe analyser, ion etching with argon ions and microhardness testing.Only iron, silicon and small amounts of sulphur were detected in the radula. The teeth can be subdivided into a cusp, a junctional area where the cusp is joined to the base, and the base which is embedded in the radular membrane. From a study of longitudinal vertical and transverse sections of the mature teeth it was found that the cusp could be subdivided into a posterior iron-rich area (44–51% Fe, 1–6% Si) and an anterior silicon-rich area (22–30% Fe, 27–32% Si). The junctional zone consisted of a poorly mineralised layer at its border with the cusp and an iron-rich layer where it joined the base. The upper part of the base (5% Fe, 16% Si) could be clearly differentiated from the silicon-rich anterior and lower parts of the base (3–4% Fe, 28–35% Si). No minerals were detected in the membrane. The changes in the mineral content of the teeth cusps along the length of the radula were studied. Iron appeared in the cusps at the 25th row and the concentration increased to 28% at the 50th row. The iron was here evenly distributed throughout the cusp. Silicon appeared in the anterior part of the cusp at the 50th row and as it increased in concentration so the iron was displaced, and at the same time the concentration of iron increased in the posterior part of the cusp. Mineralization appeared to be complete by the 150th row.The teeth cusps appear to consist of 800 Å fibres grouped into 1 thick bundles and the tooth appears to be covered by a thin enamel-like layer. It is suggested that the fibres contain the silicon-rich phase and the matrix the iron-rich phase.The significance of the arrangement of the fibres and the distribution of the minerals are discussed with relation to the function of the teeth.We wish to thank Mr. A. Rees and Mr. A. Davies for their technical assistance; Prof. Lewis and Dr. James for the use of the Electron Microprobe; and the S.R.C. for their financial support.     

Organic matrixlike macromolecules associated with the mineral phase of sea urchin skeletal plates and teeth

The skeletal plates and teeth of the echinoid Paracentrotus lividus contain a heterogeneous assemblage of macromolecules that are not part of the connective tissue, but are presumably intimately associated with the mineral phase. Upon dissolution of the Mg-calcite mineral phase, some of these molecules are insoluble. The insoluble fractions of the teeth and skeletal plates are quite different, the former being predominantly protein and the latter, primarily some unknown nonproteinaceous material. The soluble constituents are similar in both tissues. These hydrophilic macromolecules have been partially separated and characterized. In both hard parts, two distinct classes of macromolecules are present, as indicated by the amino acid compositions of their protein constituents. These two classes of macromolecules are also present in the shells of a foraminifer and in various mollusks, both of which are formed by the "organic matrix-mediated" biomineralization process. The locations of these macromolecules in the teeth and skeletal plates are not known, nor whether they form coherent structures. It is therefore premature to conclude that these macromolecules do function as an organic matrix, although the results presented are in agreement with such an interpretation.     

Patterning the size and number of tooth and its cusps

Mice and rats, two species of rodents, show some dental similarities such as tooth number and cusp number, and differences such as tooth size and cusp size. In this study, the tooth size, tooth number, cusp size and cusp number, which are four major factors of the tooth patterning, were investigated by the heterospecific recombinations of tissues from the molar tooth germs of mice and rats. Our results suggest that the dental epithelium and mesenchyme determine the cusp size and tooth size respectively and the cusp number is co-regulated by the tooth size and cusp size. It is also suggested that the mesenchymal cell number regulates not the tooth size but the tooth number. The relationships among these factors in tooth patterning including micropatterning (cusp size and cusp number) and macropatterning (tooth size and tooth number) were analyzed in a reaction diffusion mechanism. Key molecules determining the patterning of teeth remains to be elucidated for controlling the tooth size and cusp size of bioengineered tooth.     

江西崇义地区上泥盆统节甲类(Arthrodira)的新材料

我国泥盆系鱼化石非常丰富,尤其是下、中泥盆统。但是,上泥盆统鱼化石发现尚少,而且主要是胴甲类化石,节甲类化石则很少发现。潘江（１９６２）在对斯行健已记述的一植物化石 Ｃｈａｎｇｙａｎｏｐｈｙｔｏｎ ｈｏｐｅｉｅｎｓｉｓ Ｓｚｅ重新进行观察时认为,该化石应属于盾皮鱼类,并将其归人瓣甲类 Ｍａｃｒｏｐｔｅｔａｌｉｃｈｔｈｙｉｄａｅ（？）,化石仅包括前腹侧片和胸棘。 Ｄｅｎｉｓｏｎ（１９７８）根据潘江的文章和插图则认为, Ｃｈａｎｇｙａｎｏｐｈｙｔｏｎ ｈｕｐｅｉｅｎｓｉｓ属于原始节甲类或者瓣甲类。王念忠等…     

The chiton stylus canal: An element delivery pathway for tooth cusp biomineralization

A detailed investigation of the stylus canal situated within the iron mineralized major lateral teeth of the chiton Acanthopleura hirtosa was undertaken in conjunction with a row‐by‐row examination of cusp mineralization. The canal is shown to contain columnar epithelial tissue similar to that surrounding the mineralized cusps, including the presence of iron rich particles characteristic of the iron storage protein ferritin. Within the tooth core, a previously undescribed internal pathway or plume is evident above the stylus canal, between the junction zone and mineralizing posterior face of the cusp. Plume formation coincides with the appearance of iron in the superior epithelium and the onset of mineralization at tooth row 13. The plume persists during the delivery of phosphorous and calcium into the tooth core, and is the final region of the cusp to become mineralized. The presence of the stylus canal was confirmed in a further 18 chiton species, revealing that the canal is common to polyplacophoran molluscs. These new data strongly support the growing body of evidence highlighting the importance of the junction zone for tooth mineralization in chiton teeth, and indicate that the chemical and structural environment within the tooth cusp is under far greater biological control than previously considered. J. Morphol. 2009. © 2008 Wiley‐Liss, Inc.     

The structure and function of the bursa copulatrix of the monarch butterfly (Danaus plexippus)

The bursa compulatrix of the Monarch butterfly was investigated utilizing light microscopy, histochemistry, and scanning and transmission electron microscopy in order to relate its morphology to the release of sperm from the spermatophore. The bursa has a row of large chitinous teeth on either side of the organ. The dorsal and ventral surfaces are covered with chitinous plates, the plates having bristles on one side. A single layer of cells lies under both the plates and teeth, one columnar cell under each plate, one cuboidal cell under each tooth. The toothed area has no muscle cells. However, the dorsal and ventral hemispheres of the bursa each have a crescent-shaped packet of muscle fibers that traverse the organ; there are no longitudinal fibers. Spermatophores with thick walls were found in the bursal lumen. Morphological evidence suggests that the presence of the spermatophores is sensed by the bristles and that the packets are opened by contraction of the muscles bringing the large teeth into contact with the spermatophore wall.     

Time-related PDL: viscoelastic response during initial orthodontic tooth movement of a tooth with functioning interproximal contact-a mathematical model

Most anteroposterior orthodontic movements of posterior teeth have to overcome the "resistance" of adjacent teeth with functioning interproximal contacts. The aim of this study was to develop a mathematical model describing initial posterior tooth movement associated with functioning interproximal contacts in relation to the viscoelastic mechanical behavior of the human periodontal ligament (PDL). A linear viscoelastic 2D mathematical model was modified to depict tipping movement around the center of rotation (C(rot)) of a premolar where tipping is restrained by adjacent teeth. Equilibrium equations were applied taking into account the sagittal moment developed around the C(rot). The constants of the model were analyzed and applied to a numerical model that can simulate short-term tooth creep movement caused by a tipping force. Changes in force magnitude (0.5-3N) and crown length (6-10mm) were analyzed until no movement was observed (steady state). Premolar displacement in contact with adjacent teeth showed a non-linear progression over time with an initial sharp tipping movement followed by a transient period of 2.6-7.1min. As tipping force increased the transient period increased. A similar but smaller effect was observed with an increase in crown length. The premolar initial displacement within the arch (3.2-19.5microm) is about seven-fold smaller than retraction/protraction movement of an incisor. These suggest reduction in tooth displacement when functioning interproximal contact is present and clinically recommend establishing a space in the direction of tooth displacement before tooth movement.     

Tooth cusp sharpness as a dietary correlate in great apes

Mammalian molars have undergone heavy scrutiny to determine correlates between morphology and diet. Here, the relationship between one aspect of occlusal morphology, tooth cusp radius of curvature (RoC), and two broad dietary categories, folivory and frugivory, is analyzed in apes. The author hypothesizes that there is a relationship between tooth cusp RoC and diet, and that folivores have sharper teeth than frugivores, and further test the correlation between tooth cusp RoC and tooth cusp size. Eight measures of tooth cusp RoC (two RoCs per cusp) were taken from 53 M²s from four species and subspecies of frugivorous apes (Pongo pygmaeus, Pan troglodytes troglodytes, Pan troglodytes schweinfurthii, and Gorilla gorilla gorilla) and two subspecies of folivorous apes (Gorilla beringei beringei, and Gorilla beringei graueri). Phylogenetically corrected ANOVAs were run on the full dataset and several subsets of the full dataset, revealing that, when buccolingual RoCs are taken into account, tooth cusp RoCs can successfully differentiate folivores and frugivores. PCAs revealed that folivores consistently had duller teeth than frugivores. In addition, a weak, statistically significant positive correlation exists between tooth cusp size and tooth cusp RoC. The author hypothesizes differences in tooth cusp RoC are correlated with wear rates, where, per vertical unit of wear, duller cusps will have a longer length of exposed enamel ridge than sharper cusps. More data need to be gathered to determine if the correlation between tooth cusp RoC and tooth cusp size holds true when small primates are considered. Am J Phys Anthropol 153:226–235, 2014. © 2013 Wiley Periodicals, Inc.     

Structure of the radially asymmetrical uncalcified region of the teeth of the red-backed salamander,Plethodon cinereus (Amphibia,Plethodontidae)

The teeth of the adult plethodontid salamander, Plethodon cinereus, were examined by light and electron microscopy with emphasis on the ringlike zone of uncalcified dentin that divides the calcified portion of each tooth into a proximal pedestal and a distal apex. The uncalcified region displays radial asymmetry, forming an integral part of the posterior wall of the tooth but bulging into the pulp cavity anteriorly, thus forming a hingelike structure. All portions of the dentin, including the uncalcified region, are composed predominantly of collagenous fibers but lack elastin. In scanning electron micrographs of teeth from which the oral mucosa has been removed, the location of the anterior uncalcified hinge is marked externally by a notch-like articulation of the apex and pedestal. Sites of transition between calcified and uncalcified areas of the dentin show no special modifications in transmission electron micrographs, but collagenous fibers in calcified portions are associated with more electron-dense amorphous material than are those in the uncalcified region. Odontoblasts associated with the uncalcified region possess ultrastructural features closely resembling those of odontoblasts found in calcified areas. The uncalcified region seems to afford the teeth a certain degree of flexibility, and the asymmetry of the region appears to allow the teeth to flex only in a posterior direction, thus facilitating the entry of living prey but hindering its escape. The uncalcified region also seems to permit the apex of a tooth to break away from its pedestal without damage to underlying bone.     

Structure and mechanical properties of the soft zone separating bulk dentin and enamel in crowns of human teeth: insight into tooth function

The 200-300 microm soft zone of dentin, found beneath enamel in crowns of human teeth, is thought to fulfill important roles in tooth function, but little is known about its structure-mechanical relations. Scanning electron microscopy images of fracture surfaces showed that near the dentino-enamel junction (DEJ), a porous reticulate matrix of intertubular-dentin contains tubules with no peritubular lining. Peritubular-dentin however is found at some distance from the DEJ, and it gradually thickens with increasing depth into the bulk dentin. Concurrently, tighter packing of the collagen fibers is observed with a gradual increase in mineral deposits on and between the fibers. This structurally graded zone is known to be softer when tested for micro-hardness. It undergoes greater strain compared to bulk dentin, when measured using Moiré interferometry. We investigated the deformation and stiffness of this zone by means of non-contact laser-speckle interferometry (ESPI), and nanometer-scale deformations were tracked during compression-testing performed in water. We report a significantly reduced stiffness of this zone compared to bulk dentin, with mid-buccal regions of teeth averaging 3.5 GPa compared with 9.7 GPa in mid-lingual regions. Our results support and expand upon the hypothesis that the durability of the whole tooth relies upon a bucco-lingual asymmetric matching of stiffness by means of an interphase: a cushioning soft layer between enamel and bulk dentin.     

The ultrastructure of odontogenesis in larval and adult urodeles; differentiation of the dental epithelial cells

Summary Sections of undemineralized tooth germs ofAmbystoma andTriturus were examined. The ultrastructure of early germs, both larval and adult, and of dentinogenesis, resembled that of mammals. In adult bicuspid teeth, once the dentine of the cusps was mineralized, mineral crystals of a similar size to early mammalian enamel crystals, appeared between the dentine and the inner dental epithelium (i.d.e). Concomitantly, the i.d.e showed features of mammalian secreting ameloblasts. This new layer, regarded as true enamel, lacked collagen, possessed an ordered arrangement of crystals and reached a maximum thickness of 6 m.In larval monocuspid teeth, once dentine mineralization had reached the plasma membranes of the i.d.e at the tip of the cusp, the i.d.e developed a ruffled border. At this stage the dentine of the tip, regarded as enameloid, was very hard and difficult to section. The ruffled border, characteristic of other cells which transport materials, was regarded as indicating that the i.d.e was removing organic matter from the enameloid. The differences in development between larval and adult teeth support the concept that there is a change in cellular activity of the i.d.e which occurs during metamorphosis from the larval to the adult urodele.     

Factors affecting the distribution of enamel hypoplasias within the human permanent dentition

Frequencies and morphological and chronological distributions of enamel hypoplasias are presented by tooth type (permanent I1 to M2s), based on a sample of 30 prehistoric Amerindians with complete and unworn dentitions. There is nearly a tenfold variation in frequency of defects by tooth, ranging from 0.13 per mandibular second molar to 1.27 per maxillary central incisor. The six anterior teeth average between 0.70 and 1.27 defects/tooth, whereas the eight posterior teeth average between 0.43 and 0.13 defects/tooth. Earlier developing teeth, such as incisors, have earlier peak frequencies of defects (2.0-2.5 years), while later developing teeth, such as second molars, have subsequent peak frequencies (5.0-6.0 years). These variations are relevant when comparing hypoplasia data based on different teeth. Differences in hypoplasia frequencies among teeth are not solely due to variation in time of crown development, as is usually reported. Rather, there is evidence for biological gradients in susceptibility to ameloblastic disruption. Anterior teeth are more hypoplastic than posterior teeth. More developmentally stable "polar" teeth are more hypoplastic than surrounding teeth. Polar teeth may be more susceptible to hypoplasias because their developmental timing is less easily disrupted. In all teeth, hypoplasias are most common in the middle and cervical thirds. Crown development and morphological factors, such as enamel prism length and direction, may influence the development and expression of enamel surface defects.     

部分蜥蜴类牙齿特征补充

The characteristics of modern lizard teeth have often been overlooked as an aid to classification. In order to i-dentify isolated teeth or rows of teeth on the jaws of Quaternary lizard fossils, we observed many modern lizard skulls with complete tooth rows, and thereby discovered that there are different patterns of tooth arrangement which are a significant aid to classification and also valuable in distinguishing lizard tooth fragments or isolated teeth. Our observations suggest that lizard teeth can be divided into three major types: 1 ) Homodont, pleurodont with single-cusp. This kind of teeth is usually slender and closely spaced. Teeth number 20 - 30 or more. The smaller-sized lizards, such as Gekkos gecko, G.Japonicus, Eumeces chinensis (Fig. 1 :A, a), E. xanthi, Leiolopisma tsinlingensis (Fig. 1 :B, b), L. reevesii, Ly-gosoma indicum, Platyurus platyurus and Hemidactylus frenatus, have this kind of arrangement. 2) Heterodont, sub-acrodont or pleurodont, with single-conical cusp teeth at the anterior of the tooth row and with flat-conical bicuspid teeth posteriorly. There are about 18 - 19 check teeth. Eremias argus (Fig. 1:C,c), E. multiocellata and E. brenchltyi have this kind of arrangement. 3 ) Heterodont, with single-conical cusp teeth in the anterior part of the tooth row and with tricuspid, subacrodont teeth posteriorly. There are vertical grooves between the teeth on the external side of the low-er jaw. The fourth tooth in most species is canine-like. There are 16 or less check teeth. The larger-sized lizards, such as Phrynocephalus przewalski, P. frontalis (Fig. 1:D,d), Japalura splendida, J. flaviceos (Fig. 1 : E, e), Calotes versicolor and Leioleps belliana etc. possess this kind of arrangement. Evolutionary trends in lizard teeth are briefly dis-cussed.     

The size and morphology of the Nasioi dentition

Dental impressions were obtained on 240 Nasioi, a Melanesian population living on the island of Bougainville. Odontometric data are presented for both the permanent and deciduous teeth, and the former teeth are also examined morphologically. The results show that the Nasioi have large permanent teeth like other Australoid populations whereas the deciduous teeth are only of moderate size. The coefficients of variation are large in the permanent teeth compared to other populations but the sexual dimorphism in tooth size and variability is not remarkable. Morphologically, the permanent teeth of the Nasioi are characterized by a cusp number pattern, a high frequency of the Dryopithecus + pattern on the first mandibular molar, few individuals with a Cusp of Carabelli, and a moderate expression of shovelled-shaped anterior teeth.