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1

Badanie zmian temperatury podczas polimeryzacji światłoutwardzalnych dentystycznych materiałów kompozytowych

Świderski W., Malara P., Świderska J., Czech Z.

Przemysł Chemiczny

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2017

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T. 96, nr 5

1179--1182

PL

Przeprowadzono badania zmian temperatury podczas polimeryzacji dwóch materiałów kompozytowych o różnych matrycach (siloranowej i metakrylanowej) w zależności od rodzaju zastosowanej lampy polimeryzacyjnej, odległości od źródła światła i czasu naświetlania. Temperatura podczas naświetlania materiału Filtek Silorane o matrycy siloranowej była istotnie wyższa od temperatury materiału Filtek P60 o matrycy metakrylanowej. Zaobserwowano też istotnie większy wpływ czasu naświetlania na zmiany temperatury podczas naświetlania lampami LED (light-emitting diodes) niż lampą halogenową.

EN

Two com. resin-based composites with silorane-and methacrylate-based matrices were photocured at varying light-curing unit and composite type, curing distance and curing time to obs. the temp. changes. The silorane-based composite was cured at significantly higher temp. when compared with the methacrylate-based one. The curing time showed a stronger effect on temp. changes when the light-emitting diode was used as the light source than when halogen lamp was used.

2

Temperature changes influenced by different types of light curing units during polymerization of resin-based dental composite materials

Malara P, Świderski W., Świderska J.

Archives of Materials Science and Engineering

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2016

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Vol. 79, nr 2

64--70

EN

Purpose: of this study was to evaluate the influence of LCU type on temperature changes during polymerization of two resin-based composites with different matrices (silorane-based and methacrylate-based). Design/methodology/approach: The light-curing units (LCUs) selected for this study included three various LEDs (LED 55, LED 10W and Radii Plus) and a QTH (Elipar Highlight). Two different resin-based composites (RBCs) were used in this study. The silorane-based composite Filtek Silorane and methacrylate-based composite Filtek P60. Temperature changes were measured during polymerization with LCUs working in various curing modes. Empty mold, Filtek Silorane RBC and Filtek P60 RBC were cured from a distance of 0 mm, 2.5 mm and 5 mm. Findings: Regardless the type of RBC, every time the highest temperature was reached with LED 55 light-curing unit. Comparing Filtek Silorane and Filtek P60 RBCs, the temperature of Filtek Silorane RBC was significantly higher with LED 55 (35.4±4.9), Radii Plus (33.5±5.5) and Elipar Highlight LCUs (31.2±3.1), and significantly lower with LED 10W LCU (28.5±7.5). For Filtek P60 the measured temperatures of polymerization were 32.7±3.2 for LED 55 LCU, 29.9±5.6 for LED 10W LCU, 31.0±2.4 for RadiiPlus LCU and 30.2±1.8 for Elipar Highlight LCU. Research limitations/implications: The research was carried out for two groups of composite materials used for teeth restoration in modern dentistry. The experiment should be repeated on a broader group of resin-based composite dental materials and should take into account more light-curing units. The study could be also done in situ on a real tooth model. Practical implications: This research gives an insight into the range of temperatures that are generated during polymerization process of dental composite materials. The results of the study are of a great value during choosing the restorative composite material for particular application in the oral cavity, selecting the right light-curing-unit and adjusting the curing parameters Originality/value: The results of the study allow to conclude that the temperature values vary for each resin-based material, according to light-curing-unit type and the distance of curing seemed to have least influence on temperature changes during polymerization.

3

Reducing of on polymerization shrinkage by application of UV curable dental restorative composites

Świderska J., Czech Z., Świderski W., Kowalczyk A.

Polish Journal of Chemical Technology

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2014

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Vol. 16, nr 3

51--55

EN

This manuscript describes dental compositions contain in-organic fillers, multifunctional methacrylates and photoinitiators. The main problem by application and UV curing process is the shrinkage of photoreactive dental materials during and after UV curing process. Total shrinkage of UV curable dental composites is a phenomenon of polymerization shrinkage, typical behavior for multifunctional methacrylates during polymerization process. The important factors by curing of dental composites are: kind and concentration of used methacrylates, their functionality, double bond concentration, kind and concentration of added photoinitiator and UV dose. They are investigated UV-curable dental compositions based on 2,2-bis-[4-(2-hydroxy-3-methacryxloyloxypropyl)phenyl]propane (Bis-GMA) and containing such multifunctional monomers as 1,3-butanediol dimethacrylate (1,3-BDDMA), diethylene glycol dimethacrylate (DEGDMA), tetraethylene glycol dimethacrylate (T3EGDMA), trimethylolpropane trimethacrylate (TMPTMA), polyethylene glycol 200 dimethacrylate (PEG200DA). Reduction of polymerization shrinkage of dental compositions is at the moment a major problem by dental technology.

4

Probabilistic graphical model supporting early diagnosis of autism spectrum disorder

Szczygieł J., Oniśko A., Świderska J., Krysiewicz E., Sienkiewicz J.

Advances in Computer Science Research

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2014

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Nr 11

151--164

EN

Bayesian networks are recognized as a suitable tool for modelling diagnostic problems. The power of this modelling is that it can combine knowledge coming from different sources. For example, in case of medical domain, the expert knowledge can be merged along with the medical data. This paper presents a Bayesian network model for early diagnosis of autism. The model was built based on the medical literature and then was revised by two domain experts. Our tool is dedicated to parents that can perform an early diagnosis of their child before visiting a specialist.

PL

Sieci bayesowskie są często używanym narzędziem w rozwiązywaniu problemów diagnostycznych. Jedną z zalet tego narzędzia jest mozliwość łączenia wiedzy pochodzącej z różnych źródeł. Na przykład, wiedza ekspertów może być połączona z danymi. W naszym artykule prezentujemy model sieci bayesowskiej wspomagający wczesne diagnozowanie autyzmu. Model został zbudowany w oparciu o literaturę medyczną, a następnie zweryfikowany przez ekspertów. Narzędzie, które stworzyliśmy jest dedykowane rodzicom, którzy mogą dokonać wstępnej diagnozy zanim skontaktują się ze specjalistą.

5

Polymerization shrinkage by investigation of uv curable dental restorative composites containing multifunctional methacrylates

Świderska J., Czech Z., Kowalczyk A.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 2

81-85

EN

Typical commercial restorative dental compositions in the form of medical resins contain in-organic fillers, multifunctional methacrylates and photoinitiators. The currently used resins for direct composite restoratives have been mainly based on acrylic chemistry to this day. The main problem with the application and radiation curing process is the shrinkage of photoreactive dental materials during and after UV curing. Shrinkage of restorative radiation curable dental composites is a phenomenon of polymerization shrinkage, typical behavior of multifunctional methacrylates during the polymerization process. The important factors in curing of dental composites are: the kind and concentration of the used methacrylate, its functionality, double bond concentration, the kind and concentration of the added photoinitiator and UV dose emitted by the UV-lamp. They are investigated multifunctional 1,3-butanediol dimethacrylate (1,3-BDDMA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol dimethacrylate (TEGDMA), trimethylolpropane trimethacrylate (TMPTMA), 2,2-bis-[4-(2-hydroxy-3-methacryxloyloxypropyl) phenyl]propane (Bis-GMA), ethoxylated Bis-GMA (EBPDMA) and dodecandiol dimethacrylate (DDDMA). Reduction of polymerization shrinkage of restorative dental compositions is at the moment a major problem of dental technology. This problem can be solved through an application of photoreactive non-tacky multifunctional methacrylates in the investigated dental adhesive fillings.

6

Acrylic Pressure-Sensitive Adhesives Containing SiO2 Nanoparticles

Czech Z., Kowalczyk A., Ortyl J., Świderska J.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 1

12-14

EN

The use of acrylic pressure-sensitive adhesives (PSAs) is increasing in a variety of industrial fi elds. They have been applied in the manufacture of mounting tapes, self-adhesive labels, protective fi lms, mas king tapes, splicing tapes, carrier-free tapes, sign and marking fi lms, and in diverse medical products, such as pads or self-adhesive bioelectrodes. In this study, the application of SiO2 nanoparticles in acrylic PSA was investigated. The properties of the newly synthesized and modifi ed PSA were evaluated via the tack, peel adhesion, shear-strength and shrinkage. It has been found that the nanotechnologically-reinforced systems consisting of monodisperse non-agglomerated SiO2 nanoparticles and self-crosslinked acrylic PSAs showed a great enhancement in tack, peel adhesion, shear resistance and shrinkage, without showing the disadvantages known to result from the use of other inorganic additives. In this paper we evaluate the performance of SiO2 nanoparticles with a size of about 30 nm as inorganic fi ller into the synthesized solvent-borne acrylic PSA.

7

Influence of the unsaturated photoinitiators kind on the properties of uv-crosslinkable acrylic pressure-sensitive adhesives

Czech Z., Kowalczyk A., Górka K., Głuch U., Shao L., Świderska J.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 3

83-87

EN

UV-crossinkable pressure-sensitive adhesives (PSA) materials are called, in the adhesives trade photoreactive self-adhesive. UV-crosslinkable PSAs are designed after the UV-initiated crosslinking reaction to stick to almost any surface by a simple contact under light pressure. This special class of adhesives does not undergo any physical transformation or chemical reaction during the bonding process. Because of the rheological properties the adhesive must be fi nely tuned for the application, combining a carefully chosen polymer architecture and monomer composition with the proper addition of small additives called photoinitiators. The best way is using the unsaturated copolymerizable photoinitiators and their direct incorporation into polymer chain during the polymerization process. Progress in the coating technology and the development of novel photoreactive acrylic adhesives will open the door to new applications and an extended market penetration of UV-crosslinkable acrylic adhesive raw materials containing unsaturated copolymerizable photoinitiators incorporated into the polymer backbone. Photoreactive UV-crosslinkable acrylic PSA are characterized by good tack, good adhesion, excellent cohesion and very low shrinkage.

8

Adhesion measurement of pressure-sensitive adhesives

Czech Z., Sowa D., Kowalczyk A., Świderska J.

Aparatura Badawcza i Dydaktyczna

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2012

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T. 17, nr 2

7-11

EN

The term pressure-sensitive adhesive (PSA) has a very precise technical definition and was dealt with extensively in the chemical literature. Pressure-sensitive adhesives (PSA) are nonmetallic materials used to bond other materials, mainly on their surfaces through adhesion and cohesion [1]. Adhesion and cohesion are phenomena, which may be described thermodynamically and chemically, but actually they cannot be measured precisely. It was shown [2] that the most important bonding processes are bonding by adhesion and bonding with pressure-sensitive adhesives. A theoretical treatment of adhesion in terms of intermolecular interaction is not just confined to bond energies; other important factors are the number of contact points of the interacting atoms or molecules, intermolecular distances, the mobility of atomic groups and the structure of neighboring matter. Adhesion on the area of PSA is described by mechanical interlocking, adsorption or thermodynamic theory, electrostatic theory, chemical bonding theory, diffusion theory, adhesive effect of thin liquid films and theory of weak boundary layers. Adhesion of PSA plays the significant role by the application of self-adhesive materials in different industry branches [3].

PL

Pojęcie klej samoprzylepny jest bardzo precyzyjnie zdefiniowane i obszernie opisane w fachowej literaturze chemicznej. Kleje samoprzylepne to niemetaliczne materiały, służące do łączenia powierzchni różnorodnych materiałów poprzez adhezję oraz kohezję [1]. Adhezja oraz kohezja są zjawiskami, które można stosunkowo dokładnie opisać za pomocą termodynamiki oraz znanych reakcji chemicznych, lecz ich pomiar nie pozwala na daleko idącą precyzję. Udowodniono, że najważniejszymi procesami, prowadzącymi do bardzo trwałych połączeń, są połączenia związane z adhezją klejów samoprzylepnych [2]. Teoretyczne podstawy wielu teorii adhezji w połączeniu z oddziaływaniami energetycznymi są bardzo ważne, ale najważniejszymi parametrami zjawiska adhezji są: wielkość sklejanej powierzchni, odległość intermolekularna sklejanych powierzchni, ruchliwość, polarność oraz reaktywność grup funkcyjnych kleju samoprzylepnego. Adhezja klejów samoprzylepnych jest wyjaśniana i opisywana poprzez adhezję mechaniczną, adsorpcję, zależności termodynamiczne, teorię elektrostatyczną, teorię wiązań chemicznych, dyfuzję, teorię cienkich warstw granicznych oraz zwilżalność sklejanych powierzchni przez warstwę polimeru o właściwościach samoprzylepnych [3].

9

Wydatki publiczne i prywatne na ochronę zdrowia w Polsce i w wybranych krajach

Urbańczyk E., Świderska J.

Zeszyty Naukowe. Prace Instytutu Ekonomiki i Organizacji Przedsiębiorstw / Uniwersytet Szczeciński

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2006

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Nr 48, t. 1

359-367

EN

In many countries financing health care is becoming more and more complex. In order to compare the health care spending in various countries it is necessary to establish ways of classification of the above mentioned spending common to all these countries. The authors achieve this by dividing the spending into public and private, as well as by analyzing total spending on health care. The level of the country's economic development determines the potential possibilities of acquiring the funds, which may be earmarked for the health care.

10

Pozamedyczne czynniki wpływające na wybór gabinetu stomatologicznego przez pacjentów

Urbańczyk E., Świderska J.

Zeszyty Naukowe. Prace Instytutu Ekonomiki i Organizacji Przedsiębiorstw / Uniwersytet Szczeciński

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2006

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Nr 48, t. 2

959-965

EN

The aim of the article was to demonstrate other than purely medical factors that influence the choice of a dentist's surgery by patients. The specificity of medical services was presented here. The demand for medical services was noted as well. The factors that influence patients' behavior in the market and on the decisions made by them. This information is of a significant importance for those managing the Health Clinics.

11

Charakterystyka rynku usług stomatologicznych

Urbańczyk E., Świderska J.

Zeszyty Naukowe. Prace Instytutu Ekonomiki i Organizacji Przedsiębiorstw / Uniwersytet Szczeciński

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2006

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Nr 48, t. 2

967-974

EN

The article describes the specificity of dentistry services market, demonstrating the activities of the public and private sectors. A detailed analysis was conducted regarding the use of dentistry services on the basis of various criteria. An attempt was made to establish the costs of dentistry health care incurred by the Health-Insurance Fund and the National Health Fund for the insured in the years 2003 - 2004. The article presents also average spending on dentistry health care incurred by an average household. The last part of the article concerns the employment of dental surgeons.

12

Analiza poziomu i rodzajów pozyskiwanych środków na ochronę zdrowia

Urbańczyk E., Świderska J.

Zeszyty Naukowe. Prace Instytutu Ekonomiki i Organizacji Przedsiębiorstw / Uniwersytet Szczeciński

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2006

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Nr 48, t. 1

347-357

EN

The aim of the article was to present the principles of health care financing in Poland. Basic ways of acquiring health care funds were described. Their structure and their share in health care financing was analyzed in detail, demonstrating which of the ways of financing has the biggest share. A detailed analysis was conducted regarding the level and kinds of funds acquired for health care in the years 1999 - 2003.