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1

Osteocyte lacunae density in dentine-induced ectopic bone

100%

Galus R., Wlodarski P., Mazur S., Wlodarski K., Brodzikowska A.

Folia Biologica

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2016

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tom 64

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nr 2

2

The record of the reproductive cycle in the incisor dentine of spotted souslik Spermophilus suslicus

100%

Trunova Y. E., Lobkov V. A., Klevezal G. A.

Acta Theriologica

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1999

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tom 44

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nr 2

To examine the changes in dentine microstructure in spotted souslik Spermophilus suslicus (Giildenstaedt, 1770) during pregnancy, parturition and lactation, we investigated 39 females from the Odessa region. Thirty females were dead-trapped in March-July, 1987-1997, nine females (lactating or pregnant) were caught in April, 1996, injected with tetracycline as a time marker and kept in captivity during 14-47 days. Their litters survived from 1 to 29 days. We analyzed cross stained sections as well as cross ground sections of upper incisors. In the lactating sousliks both in nature and in captivity the daily layers formed in the course of pregnancy were followed by formation of a specific dentine pattern. The pattern consisted of alternating contrastive hypo- chromatic and hyperchromatic bands of about 30-50 n wide. The beginning of the pattern formation coincided approximately with parturition and the formation continued during lactation. Therefore, the parturition-lactation zone could be the correct name for the pattern. In captured females no correlation between the duration of the pattern formation and the lifespan of their litters was found. The pattern was absent in immature and barren females. We found no changes in the dentine formation during pregnancy.

3

Dental incremental lines in some small species of the European vespertilionid bats

100%

Batulevicius D., Pauziene N., Pauza D. H.

Acta Theriologica

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2001

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tom 46

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nr 1

The dentine and cementum of the mammals exhibit incremental lines (IL) that may be seen as dark and light rings in properly prepared sections of teeth. Counting of IL provides a potential method to evaluate the absolute age of many wild species. The aim of the present study was to evaluate IL in small bat species and to test whether the number of IL is associated with the absolute age of bat when its minimal age was known based on ringing data. Teeth of 26 specimens of the following species were examined: Myotis daubentonii (n = 12), Barbastella barbastellus (n = 4), M. brandtii (n = 2), M. nattereri (n = 2), Pipistrellus nathusii (n = 2), Plecotus auritus (n = 2), M. dasycneme (n = 1), Vespertilio murinus (n = 1). Transverse morphological sections of canines, incisors and postcanine teeth were analysed by a light microscopy. In 4 cases, the minimal age of animals examined in this study was known. The IL were revealed in the dentine of 14 bats examined. The cementum of all animals was devoid of IL. The mean distance between the first and second juxtaposed IL of M. daubentonii was 3.2 ± 0.2 ^m, but it was significantly fewer among the subsequent adjacent lines. Due to a thinness of the IL, an accurate counting was considerably difficult in the canines containing more than 10 IL, as well as in the incisors and postcanine teeth with more than 3-6 IL. The IL of roots showed the most contrast, but they were almost obscured from view at the cingulum and crown. In bats of known-age, the numbers of IL were significantly lower than minimal age of those animals examined, and IL were either revealed only in certain teeth or absent entirely in all teeth. The present findings suggest that the number of the IL varies in different teeth and is strongly dependent on section level. Consequently, age determination in small bats using dental IL is doubtful and requires a reevaluation.

4

Zonula adherens as a transmitter of low charge electric current

100%

Alwas-Danowska H. M.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

5

Dentinogenesis imperfecta type II: Ultrastructure of teeth in sagittal sections

84%

Wieczorek A., Loster J.

Folia Histochemica et Cytobiologica

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2013

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tom 51

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nr 3

6

Comparison of the photosensitivity of biofilms of different genera of cariogenic bacteria in tooth slices

84%

Darmani H., Tawalbeh K. H., Al-Hiyasat A. S., Al-Akhras M.-A.

Polish Journal of Microbiology

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2018

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tom 67

|

nr 4

This study compared the outcome of photosensitization on the viability of four different cariogens in planktonic form as well as biofilms in human dentine. Photodynamic therapy was carried out with a gallium aluminium arsenide laser (670 nm wavelength) using Toluidine blue O (TBO) as the photosensitizer. Cariogenic bacteria (Streptococcus mutans, Lactobacillus casei, Streptococcus salivarius and Actinomyces viscosus) were exposed to TBO and then to the laser for 1 minute in planktonic suspension. Then, tooth slices previously incubated for 24 hours with broth cultures of broth culture of the four cariogenic organisms were exposed to antimicrobial photosensitization. The control samples consisted of planktonic and sessile cells that were exposed to TBO alone, laser alone and the bacterial cells that were not treated with TBO or laser. The results showed significant reductions in the viability of S. mutans, L.casei and A. viscosus in both planktonic form (to 13%, 30%, and 55%, respectively) and sessile form hosted in dentinal tubules (to 19%, 13% and 52%, respectively), relative to the controls. S.salivarius was the least affected in planktonic (94% viability) and sessile form (86% viability). In conclusion, sensitivity to photosensitization is species-dependent and sessile biofilm cells are affected to the same extent as their planktonic counterparts.

7

Fluoride alters type I collagen expression in the early stages of odontogenesis

84%

Maciejewska I., Spodnik J. H., Domaradzka-Pytel B., Sidor-Kaczmarek J., Bereznowski Z.

Folia Morphologica

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2006

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tom 65

|

nr 4

359-366

Fluoride alters the expression and post-translational modifications of extracellular matrix proteins in dentin. The aim of our study was to determine the effects of fluoride on type I collagen expression during the early stages of tooth germ development in rats. Pregnant dams were divided into three groups and fed a standard diet. From the fifth day of pregnancy the three groups received tap water with, respectively, trace amounts of fluoride (C), a low fluoride concentration (FL) or and a high fluoride concentration (FH). Changes in type I collagen expression and distribution were evaluated. The expression of type I collagen was restricted to the extracellular spaces of cells of mesenchymal origin. In the youngest animals the most intense immunoreactivity for type I collagen was detected in predentin of the FL group. Although the intensity of immunostaining increased in proportion to the age of the animals, the largest increase in the groups investigated was detected in the FL group. We concluded that a low concentration of fluoride can act as a stimulator of type I collagen deposition in the extracellular matrix of dentin, while high concentrations of fluoride have an opposite effect, acting as an inhibitor of type I collagen formation in dentin.

8

Influence of diet and fluoride on dentin and enamel deposition and maturation in rats

84%

Maciejewska I., Adamowicz-Klepalska B., Kmiec Z., Dziewiatkowski J.

Folia Morphologica

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2000

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tom 59

|

nr 2

9

Effects of diet and fluoride on early phases of odontogenesis in rats

84%

Maciejewska I., Adamowicz-Klepalska B.

Folia Morphologica

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2000

|

tom 59

|

nr 1

The influence of diet and fluoride on odontogenesis in rats was investigated. 20 foetuses, 20 days old, were divided into four groups. The control group was fed with the standard diet and drank water with 0.16 mg F/l. The second, third and fourth groups were fed with the deficit, experimental diet and drank distilled water with 10 and 110 mg of natrium fluoride per litre or without fluoride. In each group, the observed tooth-bud development assumed different stages. The less advanced cap stage assumed the tooth-bud in the group fed with the deficit diet and given distilled water without fluoride. In the remaining groups, the development of observed first molars in mandible assumed the different level of its advancement in the same stage of odontogenesis — bell stage.

10

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A microanatomical and histological study of the postcranial dermal skeleton of the Devonian actinopterygian Cheirolepis canadensis

67%

Zylberberg L., Meunier F. J., Laurin M.

Acta Palaeontologica Polonica

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2016

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tom 61

|

nr 2

The Devonian stem-actinoterygian Cheirolepis canadensis is potentially important to understand the evolution of the dermal skeleton of osteichthyans, but the last detailed histological study on this taxon was published more than forty years ago. Here, we present new data about the morphology and the histological structure of scales, fulcra, and fin-rays in the Devonian actinopterygian Cheirolepis canadensis through SEM and photomicroscopy. The scales have a typical palaeoniscoid organisation, with ganoine layers overlaying dentine and a bony basal plate, but the ganoine surface lacks the characteristic microtubercles that have been described on the ganoine surface of the scales of polypterids and many other actinopterygians. Fin-rays are composed of segmented and ramified lepidotrichia that show a structure reminiscent of scales, with ganoine and dentine components lying on a thick bony base. We describe articular processes between lepidotrichia that are reminiscent of, and plausibly homologous with, the peg-and-socket articulations between the scales. The analysis of the postcranial dermal skeleton of Cheirolepis canadensis shows that structural similarities between scales and lepidotrichia of this basal actinopterygian are greater than in more recent actinopterygians. The new data on histological and microanatomical structure of the dermal skeleton lend additional support to the hypothesis that lepidotichia are derivatives of scales, though they are also compatible with the more general hypothesis that scales, lepidotrichia and fulcra belong to the same morphogenetic system.

11

Diversity of tissues in acanthodians with Nostolepis-type histological structure

67%

Valiukevicius J., Burrow C. J.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 3

Acanthodian scales with Nostolepis−type histological structure are separated into five groups based on the presence/absence and extent of stranggewebe, odontocytic and syncitial mesodentine networks, cellular unipolar mesodentine, bone−like mesodentine and durodentine in scale crowns. Two new families of acanthodians are erected, based primarily on histological structure of scales: the Vesperaliidae (stranggewebe extending throughout the scale crown) and the Acritolepidae (bone−like mesodentine in the scale crown). The latter family includes species erected for articulated fish. The families Tchunacanthidae and Lenacanthidae are united in the single family Tchunacanthidae, characterized by having scale crowns with mesodentine formed mainly by unipolar cells. A sixth group, which we exclude from the Nostolepis−type, has scale crowns composed of dentine without lacunae, plus durodentine, and bases with only rare osteocyte cavities. The new groups promote the revision and reassignment of many “nostolepid” taxa, in particular removing many species from the genus Nostolepis. Four new genera are erected: Pechoralepis (including part of Nostolepis), assigned to Acritolepidae nov.; and three genera assigned to an indeterminate family, which scales are composed of only odontocytic mesodentine without stranggewebe: Nostovicina (including part of Nostolepis), Nobilesquama (including part of Nostolepis), and Peregrinosquama (including part of Watsonacanthus). Histological structures are considered the primary characters of taxonomical value when based on isolated scales. Unfortunately, scale histology is unknown for most articulated acanthodians.

Ograniczanie wyników

Osteocyte lacunae density in dentine-induced ectopic bone

The record of the reproductive cycle in the incisor dentine of spotted souslik Spermophilus suslicus

Dental incremental lines in some small species of the European vespertilionid bats

Zonula adherens as a transmitter of low charge electric current

Dentinogenesis imperfecta type II: Ultrastructure of teeth in sagittal sections

Comparison of the photosensitivity of biofilms of different genera of cariogenic bacteria in tooth slices

Fluoride alters type I collagen expression in the early stages of odontogenesis

Influence of diet and fluoride on dentin and enamel deposition and maturation in rats

Effects of diet and fluoride on early phases of odontogenesis in rats

A microanatomical and histological study of the postcranial dermal skeleton of the Devonian actinopterygian Cheirolepis canadensis

Diversity of tissues in acanthodians with Nostolepis-type histological structure