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The evaluation of the effect of carbon dioxide laser radiation on dentine tissue

Ryniewicz J., Ryniewicz W. I., Loster J. E., Wieczorek A., Pytko-Polończyk J.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 1

181--188

EN

Purpose: Tissue constitution and construction determine the scope of the structural changes that develop under laser light. The aim of this study was to analyze the effects of carbon dioxide (CO2) laser light on the structure and elemental composition of dentine. Methods: The evaluation was conducted on samples from extracted teeth. The surface of the dentine was exposed to the radiation from a CTL 1401 CO2 laser (Centre of Laser Technology, Poland). The radiation and frequency parameters were as follows: group I with 5 W and 1 Hz, group II with 10 W and 1 Hz, group III with 5 W and 5 Hz, and group IV with 10 W and 5 Hz. The altered dentine structure was macroscopically and microscopically evaluated using a Nova NanoSEM 200 Scanning Electron Microscope (FEI Europe) with integrated microanalysis X-ray system for elemental analysis in points. Results: There were significant differences between groups in the macro- and microstructure of laser defects. Conclusions: CO2 laser radiation causes irreversible, destructive changes in dentine. The structural dentine lesions developed under the influence of the CO2 laser radiation may hinder proper adhesion of bonding systems with the damaged tissue. Laser defects in the structure should be treated like defects of noncarious origin requiring preparation and filling with composite materials in accordance with the procedures.

2

Połączenie cementów samoadhezyjnych z zębiną za pomocą samotrawiących systemów wiążących

Sokołowski G., Szynkowska M. I., Sokołowska D., Łapińska B., Domarecka M., Sokołowski J.

Przemysł Chemiczny

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2014

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T. 93, nr 9

1607-1611

PL

Przedstawiono wyniki doświadczalnych badań możliwości uzyskania lepszego jakościowo połączenia cementów samoadhezyjnych z zębiną po zastosowaniu samotrawiących systemów wiążących. Systemy samotrawiące powodowały zmiany struktury i składu chemicznego powierzchni zębiny, zwiększały też istotnie, choć w różnym stopniu, wytrzymałość połączenia cementów samoadhezyjnych z zębiną.

EN

Dentin samples were covered with self-adhesive cements and studied for surface morphol. by scanning electron microscopy and for distribution of Ca, P, C, O and Mg by electron diffraction spectroscopy. Analogical dentin samples were preliminarily covered with self-etching adhesives, then with the cements and studied for shearing strength after curing. Use of the self-etching resulted in creasing the shearing strength of the bonds.

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Mineralization of teeth and bones of the cave bear (Ursus spelaeus) from the Biśnik Cave, Southern Poland

Rogóż A., Sawłowicz Z., Socha P., Stefaniak K.

Mineralogia

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2009

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Vol. 40, iss. 1/4

65--84

EN

The studied bones and teeth of the cave bear (Ursus spelaeus) come from the Biśnik Cave, located in the Częstochowa Upland (Southern Poland). The specimens originate from different geological layers formed since the Odra Glaciation (250–270 thousand years BP). The fossilized bones and teeth were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, FTIR spectroscopy, and INAA. They are built of recrystallized carbonate-rich apatite-(CaOH) and/or apatite-(CaOH). The teeth additionally contain some apatite-(CaF). The lack of collagen and minor REE contents suggest rapid burial and collagen decay in the early stage of diagenesis. The bones and teeth have only limited mineral infillings. In some teeth, Mn-Fe (hydroxy)oxides were found in the dentine canaliculi and in bones, some osteocyte lacunae contain Fe (hydroxy)oxides with admixture of Mn. In one bone specimen, calcite infillings are present in Haversian canals. The infillings formed during later stages of diagenesis and were succeeded by non-filled cracks.

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Numerical and experimental analysis of effort of human tooth hard tissues in terms of proper occlusal loadings

Milewski G.

Acta of Bioengineering and Biomechanics

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2005

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Vol. 7, nr 1

47-58

EN

The paper presents the results of strain gauge experiments conducted in order to determine the strain and stress distributions in all groups of human tooth crowns in terms of the proper occlusal loadings. The features simulating masticatory loadings have not been considered. The results have been compared with the numerical solutions obtained by rneans of finite element method (FEM). A good agreement between the results of both experiments has been reached. On that basis the analysis of effort distributions in enamel and dentine as well as comparison of application of strength hypotheses to hard tissues of tooth were made.

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Numeryczne wspomaganie impulsowych badań dyfuzyjności cieplnej niejednorodnych preparatów tkankowych

Sypek J., Żmuda S., Panas A.

Biuletyn Wojskowej Akademii Technicznej

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2003

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Vol. 52, nr 10

54-71

PL

Przedstawiono przykład zastosowania numerycznych technik obliczeniowych, bazujących na metodzie elementów skończonych do analizy badań dyfuzyjności cieplnej niejednorodnych preparatów tkankowych. Dla numerycznych modeli uproszczonych 1-D, 2-D i 3-D wykonano obliczenia, w oparciu o które określono wymagania dotyczące budowy modelu numerycznego, metodykę pomiarów, wielkości błędów. Omówiono problemy wynikające ze stosowania w badaniach pakietu inżynierskiego Cosmos. Zaprezentowano budowę modelu numerycznego, będącego odwzorowaniem rzeczywistego preparatu zęba. Przedstawiono porównanie uzyskanych wyników z danymi literaturowymi.

EN

The example is presented of using the finite element numerical method for analysis of thermal diffusivity of non homogeneous tissue samples. For simplified 1-D, 2-D and 3-D models the calculations have been carried out, on the basis of which the requirements concerning the architecture of the numerical model, measurement method and the error value have been established. The problems appearing during the use of the engineering Cosmos file have been discussed. The numerical model structure reflecting the real tooth is presented. The comparison of the obtained results with the literature data are also presented.