Heterochrony, dental ontogenetic diversity, and the circumvention of constraints in marsupial mammals and extinct relatives

Paleobiology ◽  
10.1666/13034 ◽  
2014 ◽  
Vol 40 (2) ◽  
pp. 222-237 ◽  
Author(s):  
Analía M. Forasiepi ◽  
Marcelo R. Sánchez-Villagra
Keyword(s):  
South America ◽  
Deciduous Tooth ◽  
Deciduous Teeth ◽  
Evolutionary Mechanisms ◽  
Morphological Disparity ◽  
Morphological Diversification ◽  
Long Period ◽  
Dental Eruption ◽  
Replacement Pattern ◽  
Ontogenetic Diversity

In marsupial mammals and their extinct relatives—collectively, metatherians—only the last premolar is replaced, but the timing of dental eruption is variable within the group. Our knowledge of fossils metatherians is limited, but is critical to understanding several aspects of the evolution and morphological diversification of this clade. We analyzed the sequence of eruption of 76 specimens of metatherians, including Sparassodonta, an extinct clade of specialized carnivores from South America. In Sparassodonta (1) the P3/p3 erupt simultaneously, in common with some didelphids (in other didelphids, p3 erupts before P3, whereas in the remaining didelphids, some peramelids, one caenolestid, andPucadelphysthis order is reversed); (2) the upper and lower molars at the same locus erupt more in synchrony than in other carnivorous metatherians in which the lower molars clearly precede the upper equivalents; (3) the upper canine in thylacosmilids and proborhyaenids is hypselodont; (4) species with similar molar morphologies have different morphologies of the deciduous premolars, suggesting diverse diets among the juveniles of different taxa; (5) deciduous teeth are functional for a long period of time, with thylacosmilids even retaining a functional DP3 in the permanent dentition. The retention of the DP3 and the hypertrophied and hypselodont upper canine of thylacosmilids represent clear heterochronic shifts. Specializations in the timing of dental eruption and in the deciduous tooth shape of sparassodonts are evolutionary mechanisms that circumvent constraints imposed by the metatherian replacement pattern and increase morphological disparity during ontogeny.

Space Maintainer Treatment In Premature Loss Deciduous Tooth

2020 ◽  
Vol 5 (1) ◽  
pp. 1-12
Author(s):  
Rey Bintang Pamungkas ◽  
Jeffrey .
Keyword(s):  
Child Development ◽  
Clinical Examination ◽  
Growth And Development ◽  
Development Process ◽  
Deciduous Tooth ◽  
Permanent Teeth ◽  
Deciduous Teeth ◽  
Space Maintainer

Abstract. Introduction: The deciduous tooth period is an important period in child development. Premature loss of deciduous teeth is defined as the loss of deciduous teeth before they approach the eruption of permanent teeth. The prevalance of premature loss offered in several studies obtained was between 4.3% and 42.6%. Method: An 10 years-old-boy accompanied by her mother came to RSGMP Unjani, complaints of lower right nack teeth missing because they have to extracted since 3 mouth ago. Tooth have been extracted because of caries. Result: Result of clinical examination was found premature loss teeth 75, 74, and 85. The space in Moyers analysis was +0.2 mm in region 3 and +0.1 mm in region 4. Patient was treated with a fungsional removable-space-maintainer on teeth 75, 74, and 85. Conclusion: The results of premature loss is excess space in the arch, so to prevent further occlusion abnormalities in child’s growth and development process, we need a special appliance that is used to protect the space due to premature loss of deciduous teeth. Keywords: Premature loss, space maintainer, deciduous teeth

The Eruption Patterns of The Teeth of Nigerian Local Pigs. Part 1: Profile of Deciduous Teeth

2021 ◽  
Author(s):  
Michael Efeturi Okandeji ◽  
Ayodeji David Lijoka ◽  
Folusho Ayobami Atiba ◽  
James Olukayode Olopade
Keyword(s):  
Animal Models ◽  
Translational Research ◽  
Deciduous Teeth ◽  
Translation Research ◽  
Dental Research ◽  
Dental Eruption ◽  
The Family ◽  
Local Pigs ◽  
Research Studies

Abstract Background: The pigs, domesticated about 6000 years ago, are highly prolific omnivores belonging to the Family Suidae and Order artiodactyla along with their other hooved counterparts. They qualify as models for various translational research studies (including dental studies) because of their anatomical and physiological similarities to humans. There is however a dearth of information as regards the deciduous dental eruption profile (sequence and timing of eruption) of the Nigerian local pigs (NLP). This study was designed to determine the deciduous eruption profile in the NLP to assist in the management of the breed and in a bid to making the NLP more obvious as suitable animal models in dental research. A total of 51 healthy piglets (from postnatal day 1) were used for this. Their oral cavities were examined every other day for 29 weeks for signs of dental eruption. Looking at Mandibular (Md) and Maxillar (Mx) eruptions for Incisors (I), Canines(C), Premolars (P) and Molars (M), the modular sequence in the NIP was Md/ Mx I3(at birth), C (at birth) →Md I1→Md P3→MxP3 →MxI1 → Md I2 →MdP4 →MxP4 →MxP2→ Md I2 →MxI2 . Result: It was observed that variations in eruption timing exist amongst individuals and sexes while variation in eruption sequence exists between NLP and various breeds of pigs based on the literature.Conclusion: The results of this study will be particularly important to farmers, and researchers into NLP especially those using pigs in Nigeria as a model for translation research.

scholarly journals Impact of transition to a subterranean lifestyle on morphological disparity and integration in talpid moles (Mammalia, Talpidae)

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Gabriele Sansalone ◽  
Paolo Colangelo ◽  
Anna Loy ◽  
Pasquale Raia ◽  
Stephen Wroe ◽  
...  
Keyword(s):  
Evolutionary Biology ◽  
Morphological Variability ◽  
Phenotypic Integration ◽  
Phenotypic Traits ◽  
Phenotypic Evolution ◽  
Morphological Disparity ◽  
Morphological Diversification ◽  
Phylogenetic Conservatism ◽  
Selective Forces ◽  
Subterranean Species

Abstract Background Understanding the mechanisms promoting or constraining morphological diversification within clades is a central topic in evolutionary biology. Ecological transitions are of particular interest because of their influence upon the selective forces and factors involved in phenotypic evolution. Here we focused on the humerus and mandibles of talpid moles to test whether the transition to the subterranean lifestyle impacted morphological disparity and phenotypic traits covariation between these two structures. Results Our results indicate non-subterranean species occupy a significantly larger portion of the talpid moles morphospace. However, there is no difference between subterranean and non-subterranean moles in terms of the strength and direction of phenotypic integration. Conclusions Our study shows that the transition to a subterranean lifestyle significantly reduced morphological variability in talpid moles. However, this reduced disparity was not accompanied by changes in the pattern of traits covariation between the humerus and the mandible, suggesting the presence of strong phylogenetic conservatism within this pattern.

Entyloma calendulae f. dahliae. [Descriptions of Fungi and Bacteria].

1984 ◽  
Author(s):  
J. E. M. Mordue
Keyword(s):  
New Zealand ◽  
North America ◽  
South America ◽  
Papua New Guinea ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
West Indies ◽  
Growing Season ◽  
Plant Debris ◽  
Long Period

Abstract A description is provided for Entyloma calendulae f. dahliae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Dahlia variabilis, D. coccinia, D. pinnata; cultivated dahlia. DISEASE: Leaf spot of Dahlia. GEOGRAPHICAL DISTRIBUTION: Widely distributed in Europe including Finland and Sweden; Africa; North America (USA); Central and South America and West Indies (Argentina, Brazil, Colombia, El Salvador, Guatemala, Jamaica, Venezuela); Asia (Burma, India, Indonesia, Israel, Japan, Malaysia, Nepal, Pakistan, Sri Lanka, Papua New Guinea); Australia and New Zealand. CMI Map 114, ed. 4, 1983. TRANSMISSION: Soil-borne. Overwinters as ustilospores buried in plant debris; not transmitted by seed or in tubers, although spread by soil attached to tubers is possible (6, 97; 17, 655; 41, 603; 49, 1050); mature ustilospores are capable of remaining viable for a long period when dry (16, 304). Conidia contribute to dissemination during the growing season (49, 1050).

Morphological Diversity In The Evolutionary Radiation Of Paleozoic and Post-Paleozoic Crinoids

Paleobiology ◽  
1999 ◽  
Vol 25 (S2) ◽  
pp. 1-115 ◽  
Author(s):  
Mike Foote
Keyword(s):  
Data Analysis ◽  
Morphological Diversity ◽  
Ecological Strategies ◽  
Developmental Systems ◽  
Morphological Disparity ◽  
Morphological Diversification ◽  
Wide Range ◽  
Evolutionary Radiation ◽  
Discrete Character

The Paleozoic and post-Paleozoic radiations of crinoids present an opportunity to explore genomic and ecological explanations for patterns of morphologic diversification. Analysis of discrete-character data that cover the principal features of the crinoid skeleton shows that both Paleozoic and post-Paleozoic increases in morphological disparity were abrupt; this is consistent with rapid exploitation of open ecological opportunities in both cases. For the post-Paleozoic, this result is sensitive to some aspects of data analysis and sampling, so it cannot be regarded as unequivocal. The deceleration in morphological diversification within each radiation is consistent with an observed decline in rates of taxonomic origination as well as with the attainment of functional or structural limits. Despite these similarities in the two radiations, Paleozoic crinoids exploited a wider range of morphological designs than did their post-Paleozoic successors. Post-Paleozoic crinoids exploited a wide range of ecological strategies despite being stereotyped in many aspects of form. This difference between the radiations is consistent with an increase in the rigidity of genetic and developmental systems. The range of post-Paleozoic designs is not in essence a subset of the Paleozoic spectrum. The two radiations resulted in morphological distributions that are largely nonoverlapping, perhaps reflecting a different range of ecological strategies.

Deciduous Tooth Chronology in the Mandible of the Domestic Pig

1976 ◽  
Vol 55 (4) ◽  
pp. 591-597 ◽  
Author(s):  
W. Sheldon Bivin ◽  
Robert C. Mc Clure
Keyword(s):  
Deciduous Tooth ◽  
Deciduous Teeth ◽  
Domestic Pig ◽  
Crown Rump Length ◽  
The Right

Specimens of known age, weight, and crown-rump length were used to characterize the chronology and histological development of the deciduous teeth in the right mandible of swine. Special observations were made concerning the deciduous origin of the first premolar tooth.

3D Accuracy of Deciduous Tooth Model Reconstructed from CBCT Scan

2012 ◽  
Vol 239-240 ◽  
pp. 798-802
Author(s):  
Hong Bo Li ◽  
Lin Liu ◽  
Yu Xuan Gao ◽  
Xiao Wei Shi
Keyword(s):  
Three Dimensional ◽  
Distribution Patterns ◽  
Deciduous Tooth ◽  
Deciduous Teeth ◽  
Tooth Surface ◽  
Surface Model ◽  
Accuracy Evaluation ◽  
Micro Ct ◽  
Anterior Teeth ◽  
Significant Difference

Objective To assess the three dimensional (3D) accuracy of deciduous tooth surface model reconstruction from cone-beam CT(CBCT) scans using image superimposition method. Methods 14 sound extracted human deciduous teeth were scanned by micro-CT and CBCT scanner. The digital tooth models reconstructed from CBCT scans were superimposed onto the standard model from micro-CT scans respectively. Distribution patterns of shape discrepancy were presented using histogram, as well as shown in different colors on the superimposed images. The voluminal discrepancy versus the volume of the standard image (RVD/VS) were calculated and analyzed, using t test. Results There was no statistically significant difference between deciduous anterior teeth and molars(P>0.05). The mean RVD/VS of digital tooth images obtained by CBCT scans was 3.932±4.038%, and significant difference were found (P<0.01), compared with the standard tooth model from micro-CT. Marked by different colors, the superimposed images could give visualized information on the dimensions and distribution patterns of discrepancies. Histogram gave the statistical description about the numbers and magnitude of the discrepancies. Conclusions The superimposition method and the concept of RVD/VS are recommended for 3D accuracy evaluation. CBCT is of high accuracy for tooth modeling and suits for clinical and research purpose.

scholarly journals Pulpotomy in deciduous tooth with mineral trioxid aggregate

2014 ◽  
Vol 62 (4) ◽  
pp. 449-452
Author(s):  
Fabiane PIVA ◽  
Fábio Herrmann COELHO-DE-SOUZA ◽  
Raquel MEIRA ◽  
Gabriela Taube ROTTA ◽  
Taytianne VOLKWEISS
Keyword(s):  
Mineral Trioxide Aggregate ◽  
Chemical Properties ◽  
Deciduous Tooth ◽  
Deciduous Teeth ◽  
Pulp Tissue ◽  
Physico Chemical ◽  
Biological Potential ◽  
Alternative Material ◽  
Deciduous Molar

Several medicines have been tested and used in the conservative pulp therapy of deciduous teeth, however, the formocresol has being the elected material in the pulpotomies, even not assisting the biocompatibility demands and promoting the fixation of the vital pulp tissue and not its repair. After Mineral Trioxide Aggregate (MTA) appearance as a material with physico-chemical properties that promotes the tissue repair, allied to other important properties, such as the antimicrobial action and the biocompatibility to the pulpal tissues, a new alternative material appeared for the dentistry. The aim of this study was to report the effect of MTA in a pulpotomy of deciduous molar, and its 1-year follow-up. The pulpotomy was made with MTA in the tooth 85 in a 5-year-old patient. The results obtained were quite favorable, demonstrating clinical and radiographic success, as well as absence of painful symptomatology reported by the patient. In spite of the little time of follow-up of the treated deciduous tooth, MTA has a great biological potential and could be an alternative material to be used in the pulpotomies of deciduous teeth.

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