Wyniki wyszukiwania - BazTech

1

Bond strength of modern self-adhesive resin cements to human dentin and different CAD/CAM ceramics

Małysa Andrzej, Weżgowiec Joanna, Danel Dariusz, Boening Klaus, Walczak Katarzyna, Więckiewicz Mieszko

Acta of Bioengineering and Biomechanics

|

2020

|

Vol. 22, no. 2

25--34

EN

The aim of the study was to evaluate the shear bond strength of CAD/CAM ceramics to dentin after cementation with conventional or self-adhesive resin cements. Methods: Three self-adhesive, self-etching cements (Panavia SA, RelyX U200, Maxcem Elite), and one conventional cement (Panavia V5), were selected to lute three CAD/CAM ceramics (IPS Empress CAD, IPS e.max CAD, IPS e.max ZirCAD) onto the dentin. The bond strength was evaluated using a shear strength test according to the PN-EN ISO 29022:2013-10. Evaluation of the differences was performed using the Statistica software. Failure modes were analyzed using a light microscope. Results: All the studied cements differed (regardless of the ceramic type) in the bond strength. The highest bond strength was observed in Panavia V5, lower – in RelyX U200 and Panavia SA, and the lowest – in Maxcem. For IPS e.max ZirCAD, it was observed that compared to Panavia V5, the other cements were characterized by a significantly higher bond strength. For the IPS Empress CAD and the IPS e.max CAD, Panavia V5 displayed the highest bond strength. For all the studied self-adhesive cements, the failure of adhesion between the cement and dentin was predominant mode. Conclusions: Significant differences were found in the shear bond strengths of the CAD/CAM ceramics luted to dentin using tested self-adhesive and conventional cements. The bond strength depended on the combination of ceramic and cement. The IPS e.max ZirCAD had the highest bond strength to dentin after cementation with RelyX U200, while the IPS Empress CAD and IPS e.max CAD – with Panavia V5.

2

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

|

2017

|

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.

3

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

|

2014

|

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.

4

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

Milewski G.

Acta of Bioengineering and Biomechanics

|

2005

|

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.

5

Numeryczne wspomaganie impulsowych badań dyfuzyjności cieplnej niejednorodnych preparatów tkankowych

Sypek J., Żmuda S., Panas A.

Biuletyn Wojskowej Akademii Technicznej

|

2003

|

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.