Title Ispitivanje optičkih svojstava zubnih keramika Title (english) Analysis of optical properties of dental ceramics Author Karla Ledić Mentor Ketij Mehulić (mentor)Committee member Dragutin Komar (predsjednik povjerenstva)Committee member Dubravka Knezović-Zlatarić (član povjerenstva)Committee member Vesna Alar (član povjerenstva)Committee member Igor Majnarić (član povjerenstva)Granter University of Zagreb Defense date and country 2015-12-16, Croatia Scientific / art field, BIOMEDICINE AND HEALTHCARE Universal decimal classificationUDC ) 616.31 - Stomatology Abstract Svrha: Dobivanje novih spoznaja o postojanosti optičkih svojstava; boji, svjetlini, kromatičnosti i translucenciji staklo-keramičkih materijala u korozivnom mediju.
Materijali i metode: Izrađeno je po tri uzorka (pločice 10 mm × 12 mm × 0,8 mm) IPS e.max keramike (Ivoclar Vivadent, Schaan, Lichtenstein) u tri boje (A2, C2 i B3) trima različitim tehnologijama izrade (slojevanje – IPS e.max Ceram Dentin; toplo-tlačna tehnika – IPS e.max Press; strojno – IPS e.max CAD). Izrađena su i 3 akrilatna uzorka (PMMA) istih dimenzija (Ivoclar Vivadent, Schaan, Lichtenstein) u 3 boje (130, 410, 310). Usporedba je rađena sa standardom, ključem boja Vitapan Classical (Vita Zahnfabrik, Bad Säckingen, Njemačka). Pomoću spektrofotometra (X-Rite DTP 20 Pulse, Neu Isenburg, Njemačka) izmjerene su CIE L*a*b* vrijednosti za izračun razlike u boji (ΔE*), kromatičnosti (ΔC*) parametra tanslucencije (TP vrijednost), prije i poslije izlaganja 4% octenoj kiselini na 80 °C tijekom 16 sati (ISO 6872). Statistički podatci obrađeni su programom IBM SPSS 22.
Rezultati: Optička svojstva koja najviše razlikuju istraživane materijale i boje su odstupanje od kromatičnosti i svjetline od standarda. Prije korozije IPS e.max Ceram Dentin ima veće odstupanje u kromatičnosti od standarda, a IPS e.max Press i CAD manje (p<0,05). IPS Ceram Dentin ima najveću svjetlinu u B3, a najmanju kromatičnost za C2 boji. Kod IPS e.max Press i CAD najveće vrijednosti svjetline imaju uzorci A2, a najmanje za C2 boji, u kromatičnosti su najveće vrijednosti za B3, a najmanje za A2 boju. Translucencija je najveća za B3 (p=0,007), najmanja za A2 kod IPS e.max Press i Ceram Dentin (p=0,028), a za CAD nema razlika. U analizi unutar tehnologije uzorci izrađeni slojevanjem (IPS e.max Ceram Dentin) imaju veću kromatičnost u sve tri boje i najmanju translucenciju. Uzorci strojne izrade (IPS e.max CAD) imaju najveću translucenciju. Svjetlina je značajno manja kod uzoraka izrađenih slojevanjem u bojama A2 i C2, a veća u B3. Izlaganje korozivnom sredstvu djeluje na smanjenje kromatičnosti što je značajno kod IPS e.max Press i IPS e.max CAD u svim bojama, a kod Ceram Dentin samo u boji B3. Korozija ne utječe na promjenu boje i svjetline te nema smanjenja translucencije osim kod B3 boje IPS e.max CAD. Akrilatni uzorci su prije i poslije korozije pokazali najveća odstupanja u svim optičkim svojstvima. Uslijed izlaganja octenoj kiselini ne dolazi do značajne promjene hrapavosti.
Zaključak: Korozija utječe na svojstva kromatičnosti i dijelom translucencije staklo-keramike.
Abstract (english) Objectives: The purpose of the study was to get new insights into stability of optical properties; colour, lightness, chromaticity and translucency of glass-ceramic materials in a corrosive medium.
Materials and methods: Three specimens (plates of 10 mm × 12 mm × 0.8 mm) of each type of IPS e.max ceramics (Ivoclar Vivadent, Schaan, Liechtenstein) were made in three colours (A2, C2 and B3) by three fabrication techniques (layering – IPS e.max Ceram Dentin; heat-pressing – IPS e.max Press; CAD/CAM – IPS e.max CAD). Three acrylic specimens (PMMA) of the same dimensions (Ivoclar Vivadent, Schaan, Liechtenstein) were also made in 3 colours (130, 410, 310). The comparison is made with the standard Vitapan Classical shade guide (Vita Zahnfabrik, Bad Säckingen, Germany). CIE L*a*b* values were measured by a spectrophotometer (X-Rite DTP 20 Pulse, Neu Isenburg, Germany) to calculate the difference in colour (ΔE*), chromaticity (ΔC*) of translucency parameter (TP values) before and after exposure to 4% acetic acid at 80 °C for 16 hours (ISO 6872). Statistical data were analysed using the IBM SPSS 22 software.
Results: Optical properties by which analysed materials and colours differ the most are deviation from chromaticity and lightness from the standard. Before corrosion IPS e.max Ceram Dentin has greater chromaticity deviation from the standard, and IPS e.max Press and CAD lower (p<0,05). IPS Ceram Dentin has the highest lightness in the colour B3, and the lowest chromaticity for the colour C2. For IPS e.max Press and CAD, the highest lightness values have A2 specimens, and the lowest ones are for the colour C2, the highest chromaticity values are for the colour B3 and the lowest ones for the colour A2. Translucency is the highest for the colour B3 (p=0,007), and the lowest for the colour A2 of IPS e.max Press and Ceram Dentin (p=0,028), and for CAD there is no difference. In the analysis of the technology, specimens fabricated by layering technique (IPS e.max Ceram Dentin) have higher chromaticity in all three colours and the lowest translucency. Specimens fabricated by computer-aided manufacturing (IPS e.max CAD) have the highest translucency. Lightness is significantly lower for specimens fabricated by layering technique in the colours A2 and C2, and higher for the colour B3. Exposure to a corrosive medium diminishes chromaticity, which is significant for IPS e.max Press and IPS e.max CAD in all colours, and for Ceram Dentin only in the colour B3. Corrosion does not affect the change of colour and lightness and there
is no diminution of translucency, except for the colour B3 IPS e.max CAD. Acrylic specimens have showed the biggest deviations of all optical properties before and after corrosion. There is no significant change of roughness as a result of exposure to acetic acid.
Conclusion: Corrosion affects chromaticity properties and partly translucency of glass-ceramics.
Keywords
staklo-keramika
optička svojstva
boja
svjetlin
kromatičnost
translucencija
spektrofotometar
tehnike izrade
korozija
Keywords (english)
optical properties
colour
lightness
chromaticity
translucency
dental ceramics
corrosion
Language croatian URN:NBN urn:nbn:hr:127:835700 Study programme Title: dental medicine Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2017-06-08 10:43:50
