الفهرس 
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Abstract
Summary
Our study aimed to evaluate a newly introduced bioactive ionic resin-based composite (ACTIVA Bioactive-Restorative) regarding its bioactivity through the assessment of remineralization ability. In addition to the amount of calcium and phosphate ion release, hybrid layer assessment and nanoleakage. Micro shear bond strength and wear resistance were also evaluated throughout the course of the study. The results of the tested properties were compared to a universal composite (Filtek Z350 XT).
The Biomaterials’ science aims at developing materials with ultimate mechanical, physical and biological properties. Physico-mechanical properties of the materials were previously the main concern of most research with less regard to biological properties. However, recently due to the interest in minimally invasive procedures, that focus seems to be shifting towards developing the bioactive aspect of biomaterials.
For in-vitro bioactivity examination, Gandolfi’s dentin remineralization test was performed. Dentin and materials disks were prepared and stored for 28 days in phosphate buffer saline. The dentin specimens were then subjected to EDX compositional depth profile analysis. The ACTIVA results revealed remineralization of the treated dentin surface, at the meanwhile the control group showed no remineralization. This came in line with our calcium and phosphate ion release results where ACTIVA showed ion release throughout the different time intervals unlike
Filtek Z350 XT.
Results of the nanoleakage test showed that there was no difference between ACTIVA using dental adhesive and Filtek Z350 XT group both showed silver nitrate deposits along the adhesive/dentin interface. At the meanwhile there was no correlation found between the microshear bond strength results and that of the nanoleakage. Regarding the microshear bond strength ACTIVA without the bonding agent use was found to be of unacceptable bond strength. However, ACTIVA with bonding agent and Filtek group showed statistically non-significant difference.
As for the hybrid layer assessment the results came to comply with the microshear bond strength findings as ACTIVA without bonding agent showed no resin tags which explains the low bond strength.
Wear resistance testing was performed by using a chewing simulator then digitally scanning the specimens. The volumetric wear loss was calculated by a software program through superimposing the pre-wear and post-wear scans. The results revealed that ACTIVA and Filtek both showed good wear resistance of no significant difference.