Utjecaj biološke osnove, optičkih svojstava i debljine gradivnih i fiksacijskih materijala na boju nadomjeska od litij-disilikatne staklokeramike

doctoral thesis

• Title (english): Influence of substrate color, optical properties and thickness of restorative materials and luting agents on the final color of lithium disilicate restorations
• Author: Slađana Milardović Ortolan
• Mentor: Ketij Mehulić (mentor)
• Committee member: Amir Ćatić (predsjednik povjerenstva)
• Committee member: Dragutin Komar (član povjerenstva)
• Committee member: Nikša Dulčić (član povjerenstva)
• Committee member: Nikola Mrvac (član povjerenstva); MBZ: 211232
• Committee member: Jasmina Stipetić-Ovčariček (član povjerenstva)
• Granter: University of Zagreb; School of Dental Medicine; (Department of Fixed Prosthodontics); Zagreb
• Defense date and country: 2014-05-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Dental Medicine; Prosthetic Dentistry
• Universal decimal classification (UDC): 616.31 - Stomatology

Abstract

Svrha je istraživanja bila odrediti utjecaj različitih boja podloge (Natural Die ND1, ND3, ND5, ND7 i ND9) i cementa (Variolink II transparentni, bijeli, opakno bijeli, žuti i smeđi) dviju debljinā (80 i 150 μm) na boju uzoraka litij-disilikatne keramike (LiS2) IPS e.max Press u četiri debljine (0,5, 0,8, 1,0 i 1,2 mm) i tri stupnja translucencije (HT, LT i MO) sa ili bez obložne keramike IPS e.max Ceram, debljinā 0,3, 0,5 i 0,8 mm. Izrađeno je ukupno 120 uzoraka (pločice Ø 11 mm) LiS2 keramike (10/skupina), 30 obložne keramike (10/skupina) i 55 ND podloga (11/boja). Na pet je podloga svake boje zalijepljen 80, a na drugih pet 150 μm debeo sloj kompozitnog cementa u pet različitih boja. Po jedna pločica bez cementa služila je kao kontrola. Pločice LiS2 preklapane su u svim kombinacijama s podlogama bez pa sa cementom te su spektrofotometrom izmjerene L*a*b* vrijednosti. Mjerenja su ponovljena i s obložnom keramikom. Izračunate su razlike u boji ΔE* te su podaci obrađeni u programu STATISTICA 10.0 primjenom ANOVA-e. Utvrđeno je kako su boja podloge, debljina i stupanj translucencije LiS2 keramike, boja i debljina cementa te debljina obložne keramike statistički značajno (p < 0,001 za sve varijable) utjecali na parametre boje modela koji je simulirao LiS2 nadomjestak. Unatoč statistički značajnom utjecaju boje i debljine cementa, samo je opakno bijeli cement uzrokovao i klinički značajnije razlike u boji. Obložna keramika statistički je značajno utjecala na parametre boje, pri čemu je, osim posvjeteljenja uzoraka, njenim dodavanjem klinički utjecaj cementa smanjen. Za uspješnu reprodukciju boje potrebno je uzeti u obzir debljinu nadomjeska, podlogu, a uvjetno i boju cementa.

Abstract (english)

Objectives: The aim of the study was to evaluate the effect of different supstrate colors, luting agent colors and thicknesses, different thicknesses and translucency levels of core ceramics, and different thicknesses of veneering ceramics on the final color of a model representing lithium-disilicate restorations.
Materials and methods: Cylindrical specimen of Natural Die material in the dimensions 11 x 5 mm were prepared in the colors ND1, ND3, ND5, ND7 and ND9 – 11 cylinders of each color. Disc specimen Ø 11 mm of IPS e.max Press LiS2 ceramics in 4 different thicknesses (0.5, 0.7, 1.0 and 1.2 mm) and 3 translucency levels (HT, LT and MO) were heat-pressed, and 3 thicknesses (0.3, 0.5, 0.8 mm) of IPS e.max Ceram veneering ceramics were prepared. That resulted in a total of 120 e.max Press specimen (4 thicknesses x 3 translucency levels x n = 10), 30 IPS e.max Ceram specimen (3 thicknesses x n =10), and 55 Natural Die specimen (5 colors x n = 11). One ND disc of each color served as control, while on the other 10 a layer of Variolink II resin cement in 5 different colors (transparent, white, white opaque, yellow and brown) and two thicknesses (80 or 150 μm) was applied. Different combinations of core discs with or without veneering ceramics were overlapped with the background discs with and without the cement layer to measure L*a*b* values using a spectrophotometer. Color differences ΔE* were calculated and data was statistically analyzed by means of STATISTICA 10.0. Analysis of variance (ANOVA) was applied.
Results: A significant influence of supstrate color (p < 0,001), thickness (p < 0,001) and translucency level (p < 0,001) of LiS2 ceramics, color (p < 0,001) and thickness (p < 0,001) of luting agent, and the thickness of veneering ceramics (p < 0,001) on the color parameters was found. Despite the fact that the color and thickness of the luting agent had a statistically significant effect, only the white opaque cement caused clinically significant, i.e. visible color shifts. Veneering ceramics of varying thickness had a statistically significant impact on the color parameters of the model which simulated an all ceramic restoration, whereby, besides increasing lightness of the samples, a decrease of the clinical impact of underlying colors (supstrate and luting agent) was noticed.
Conclusion: For optimum color-matching results the thickness of the restoration, supstrate, and conditionally luting agent color need to be taken into account.

• Keywords: litij-disilikatna staklokeramika; boja; stupanj translucencije; debljina keramike; boja cementa
• Keywords (english): veneering ceramics; dental restoration; dental cements
• Language: croatian
• URN:NBN: urn:nbn:hr:127:003227
• Study programme: Title: dental medicine; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstvo, polje dentalna medicina (doktor/doktorica znanosti, područje biomedicine i zdravstvo, polje dentalna medicina)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-05-08 11:21:48