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Morphological Changes in Hard Dental Tissues Prepared by ER:YAG Laser (Litetouch, Syneron), Carisolv and Rotary Instruments. A Scanning Electron Microscopy Evaluation

Aim: This in vitro investigation aimed to study by means of scanning electron microscope the morphological changes in hard dental tissues after using several different methods for caries removal and cavity preparation.

Materials and methods: Twenty freshly extracted human teeth with carious lesions were used in the study. They were assigned to four groups depending on the method used for preparation:

Group 1 - Cavity preparation using Er: YAG laser (LiteTouch, Syneron, Israel).

Group 2 - Chemomechanical preparation using colourless Carisolv gel (MediTeam AB, Savedalen, Sweden).

Group 3 - Mechanical rotary preparation using diamond burs and air turbine.

Group 4 - Mechanical rotary preparation using by steel burs and micromotor.

The preparations were performed strictly according to the manufacturer's instructions for proper use of instruments. The teeth samples were prepared for histological study and investigated by a scanning electron microscope at different magnification; the morphological changes in the tissues were registered and compared.

Results: There were considerable differences in the surface characteristics of the dental tissues when we analysed the photomicrographs of the specimens obtained using scanning electron microscopy (SEM). The surface after laser treatment remained highly retentive with no residual smear layer; the second best results in this respect were registered when teeth were chemomechanically excavated with Carisolv gel. The mechanical methods of cavity preparation resulted in surfaces with a smear layer of dentin without any microretentions.

Conclusion: The scanning electron microscopy of hard dental tissues prepared using steel and diamond burs showed surfaces covered with a thick smear layer that may be relevant to the subsequent bonding of adhesive restorative materials to the prepared cavity. In preparing the surface using a turbine with diamond burs the smear layer was thinner and part of the dentinal tubules orifices were open in the area of water turbulence.

SEM analysis of hard dental tissues prepared with the help of colourless Carisolv gel showed a rough, retentive surface, some of the dentinal tubule lumens obstructed by denaturated collagen and surface contaminants.

The teeth surfaces prepared with Er:YAG laser Lite Touch (Syneron) remained without smear layer and clearly exposed dentinal tubules orifices. The surfaces were highly retentive.

, Fungiform and Vallate Papillae and Surface of Interface Tongue Mucosa ( Bradypus torquatus ): Light and Scanning Electron Microscopy Study. Anat Histol Embryol, 38 , 42–48. Boshell, J. L., Wilborn, W. H., Singh, B. B. 1982. Filiform papillae of cat tongue. Acta Anat., 114 , 99–105. Chunhabundit, P., Thongpila, S., Somana, R. 1992. SEM study on the dorsal lingual surface of the common tree shrew, Tupaia glis. Acta Anat., 143 , 253–257. Ciuccio, M., Estecondo, S., Casanave, E. B. 2010. Scanning Electron Microscopy Study of the Dorsal Surface of the Tongue of Dasypus

Abstract

Alkali-activated binders are currently a widely-researched material. Thanks to the use of secondary raw materials such as slag from metallurgical production and ash from combustion, it appears to be a more promising and more environmentally friendly material than conventional cement concrete. Considerable attention is paid to the bonding phase itself, but only a few works deal with the binder-aggregate interaction. With cement concrete, much more attention is paid to this issue. This paper deals with the possibility of observation using electron microscopy and the information that can be obtained by this method. The problems of sample preparation and difficulties in the course of our own observation are observed.

specimens were identified according to ( Yamaguti 1961 ; Anderson et al ., 2009 ). The techniques used in the present study help in the observation as well as the identification of parasites. For scanning electron microscopy, the nematodes were fixed in 2 % glutaraldehyde in 0.1 M. sodium cacodylate buffer (PH 7.2), dehydrated in ethyl alcohol, critical point dried, mounted on stubs carefully and coated with gold then they were examined and photographed at varying magnifications using a JOEL JSM-5400LV scanning electron microscope at an accelerating voltage of 15 KV at

Abstract

The paper reports for the first time the occurrence of Erigeron acris subsp. angulosus in Poland. This rare European temperate plant was found in August 2014 in a former sand and gravel quarry, close to the Sobolewo reservoir in the town of Suwałki, north-eastern Poland. Species composition of the habitat is characterized by a phytosociological relevé based on the Braun-Blanquet method, diagnostic characters in comparison to the morphologically similar E. acris subsp. droebachiensis are presented using scanning electron microscopy imaging, and an identification key for E. acris s. l. in Poland is given.

. Morphological changes in hard dental tissues prepared by Er:YAG laser (LiteToch, Syneron), Carisolv and rotary instruments. A scanning electron microscopy evalution. Folia Medica 2010;52(3):46-55. 10. Storm B, Eichmiller FC, Tordik PA, et al. Setting expansion of gray and white mineral trioxide aggregate and Portland cement. J Endod 2008;34(1):80-2.

. (2003). Fingerprinting of Roman mints using laser ablation MC-ICP-MS lead isotope analysis. Archaeometry, 45, 591-597. DOI: 10.1046/j.1475.2003.00130.x. 12. Goldstein, J. I., Newbury, D. E., Echlin, P., Joy Jr, D. C., Romig, A. D., Lyman, C. E., Fiori, C., & Lifshin, E. (1992). Scanning electron microscopy and X-ray microanalysis. A text for biologists, material scientists and geologists. New York: Plenum Press. 13. Lee, R. L. (2007). Scanning electron microscopy and X-ray microanalysis. PTR, Prentice Hall. 14. Hawkes, P. W., & Spence, J. C. H. (2007). Science of

. Nat. Hist. 37: 1529-1534. Ferrito V., Papplardo A.M., Fruciano C., Tigano C. 2009 – Morphology of scale lepidonts in genus Aphanius (Teleostei: Caprinodontidae) using scanning electron microscopy – Ital. J. Zool. 76: 173-178. Gholami Z., Teimori A., Esmaeili H.R., Schulz-Mirbach T., Reichenbacher B. 2013 – Scale surface microstructure and scale size in the tooth-carp genus Aphanius (Teleostei, Cyprinodontidae) from endorheic basins in Southwest Iran – Zootaxa 3619: 467-490. Gholami Z., Esmaeili H.R., Erpenbeck D., Reichenbacher B. 2014 – Phylogenetic analysis of

Abstract

This study evaluates Ornithogalum brevipedicellatum, which was previously accepted as a synonym of O. oligophyllum, as a separate distinct species and discusses the similarities and differences between O. brevipedicellatum and its related species (O. oligophyllum and O. pamphylicum). Similarities and differences among these species were identifi ed by morphological and molecular studies. The leaf morphology and inflorescence of O. brevipedicellatum and O. pamphylicum are similar to each other, and in terms of these features, they show differences from O. oligophyllum. Some diagnostic characteristics are quite different in O. brevipedicellatum and O. pamphylicum, such as the size of tepals, length of fruiting pedicels and style. Morphological data were supported by the results obtained from molecular studies. According to a dendrogram obtained by molecular studies, O. brevipedicellatum and O. pamphylicum are similar. O. oligophyllum is more closely related to O. pyrenaicum used as an out-group. Additionally, the seeds of O. brevipedicellatum were examined with the use of scanning electron microscopy

Abstract

In this study, the anatomy and trichome micromorphology of Tanacetum macrophyllum (Waldst.& Kit.) Schultz, T. parthenium (L.) Schultz, T. poteriifolium (Ledeb.) Grierson and T. vulgare L. were examined by light microscopy and scanning electron microscopy. Some anatomical characters such as presence of secretory cavities and pith in root and mesophyll type in leaf provide information of taxonomical significance. In addition, the existence of a parenchymatic layer, which consists of elongated parenchymatic cells in the stem of T. macrophyllum, is a distinguishing character. The results obtained from scanning electron microscope studies showed that trichome micromorphology varies among examined taxa. In T. macrophyllum, the eglandular and glandular trichomes especially on disc florets, ligulate florets and cypselas are more sparse, whereas disc florets and cypselas of the other taxa are covered with abundant glandular trichomes. Additionally, T. poteriifolium and T. parthenium has a distinct distribution of glandular trichomes forming in a row across the entire cypsela surface.