Original scientific paper

Influence of Different Types of Fillers on the Degree of Conversion of ACP Composite Resins

Danijela Marović orcid.org/0000-0003-3104-5749 ; Department of Endodontics and Restorative Dentistry, School of Dental Medicine University of Zagreb, Croatia
Zrinka Tarle ; Department of Endodontics and Restorative Dentistry, School of Dental Medicine University of Zagreb, Croatia
Mira Ristić ; Laboratory for Synthesis of New Materials, Division of Materials Chemistry, Institute Ruđer Bošković, Zagreb, Croatia
Svetozar Musić ; Laboratory for Synthesis of New Materials, Division of Materials Chemistry, Institute Ruđer Bošković, Zagreb, Croatia
Drago Škrtić ; Paffenbarger Research Center, American Dental Association Foundation, Gaithersburg MD 20899, USA
Karl-Anton Hiller ; Department of Operative Dentistry and Periodontology, University Hospital Regensburg, University of Regensburg, Germany
Gottfried Schmaltz ; Department of Operative Dentistry and Periodontology, University Hospital Regensburg, University of Regensburg, Germany

Abstract

In order to diminish the polymerization shrinkage and improve mechanical properties of the composite materials containing amorphous calcium phosphate (ACP) as an active remineralizing ingredient, inert fillers were introduced into formulation. Purpose: The aim of the study was to examine the influence of the addition of different types of silanized inorganic fillers on the degree of conversion (DC) of the ACP based composites. Material and Methods: Seven ACP composites were tested: ACP control (40% ACP, 60% resin) and six composites containing 40% ACP, 5% or 10% non-releasing fillers and 55% or 50% resin. Silica fillers (12nm; 4-6% silanization), barium (0.77μm; 6% silanization) or strontium glass fillers (0.99μm; 3.2% silanization) were included into the pastes. Nanohybrid composite CeramX (Dentsply DeTrey, Germany) also served as a control. Composite specimens (10/experimental group) were polymerized for 40 sec by Bluephase C8 curing unit (Ivoclar Vivadent, Liechtenstein). The DC was determined by Fourier- transform infrared spectroscopy (System 2000 FTIR spectrometer; Perkin Elmer, UK) 20 min and 72 h after polymerization. Results: The addition of 10% of silica (74.14% and 75.90%) and 5% of strontium glass fillers (76.23% and 76.29%) did not have a detrimental influence on the DC of ACP composite resins. Both composites with added barium fillers showed the reduction in DC when compared to the ACP control. As expected, the ACP control with the lowest filler volume retained the highest conversion rate (75.38% and 76.05%), and CeramX had significantly lowest DC (56.87% and 57.97%). Conclusions: Even though the admixture of certain fillers yielded decrease of the DC of ACP composite resins, and considering the fact that it still greatly exceeded the DC of the commercial control, it might be concluded that they will not cause adverse effects associated with low DC.

Keywords

Polymerization; Composite Resins; Amorphous Calcium Phosphate; Tooth Remineralization

Hrčak ID:

76015

URI

https://hrcak.srce.hr/76015

Publication date:

20.12.2011.

Article data in other languages: croatian

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