Dimer acid (DA) was grafted onto lignin (EHL) to form a graft copolymer DA-g-EHL. The selection of the reaction type and the optimization of the reaction conditions for the grafting reaction were conducted through orthogonal and single factor experiments. FT-IR and thermal analysis were used to characterize the graft product. It was found that, compared with free radical grafting, DA can be gra...

A novel chitosan-based chelating resin modified with tris(2-aminoethyl)amine moiety (CCTS-TAA) was synthesized, and its characteristics in the collection/concentration of mercury was examined. The synthesized resin showed good adsorption toward mercury in a wide pH range, and the adsorbed mercury can be easily eluted by using 2M HNO(3) without any addition of complexing agent. The resin was the...

It is thought that externally applied bleaching agents may penetrate into the pulp chamber. This study was conducted to evaluate the diffusion of peroxide bleaching agents into the pulp chamber of teeth restored with various restorative materials. Sixty-five human extracted anterior maxillary teeth were separated into the 13 groups containing 5 teeth. Five teeth (control group) were not subject...

Polymerization shrinkage of resin composite can compromise the longevity of restorations. To minimize this problem, the monomeric composition of composites have been modified. The objective of this study was to conduct a meta-analysis to assess the clinical behavior of restorations performed with low polymerization shrinkage resin composite in comparison with traditional methacrylates-based res...

Recent clinical studies have suggested that composite resin may be an effective restorative material for the restoration of Class I and Class II preparations in primary molars for up to three years. The objective of this study was to advance understanding ot: the clinical performance of composite resin in primary molars. Two composite resin systems (Profile and Visio Fil) and two cavity prepara...

Problem statement: Dammar is a natural resin that used anciently in varnish production. The use of dammar natural resin in coating is limited by undesirable properties for application in coating where it is considered very brittle. Due to dammar's brittle nature, an aged dammar coating can be easily scratched or abraded. Approach: Dammar natural resin could be modified into SiliconeDammar by us...

OBJECTIVES This experimental study evaluated the effect of bonding application time on the microshear bond strength of composite resin to different types of glass ionomer cements (GICs). MATERIALS AND METHODS One-hundred and sixty specimens (two conventional and two resin-modified GICs) were prepared and divided into 16 groups. The surface of all specimens was prepared using two different bon...

PURPOSE The aim of this study was to compare the bonding strength, flexural strength, elastic modulus, water absorption and the expansion after water storage of new self-adhesive resin cements to commercially available dental cements. METHODS Two types (hand-mix and auto-mix) of new self-adhesive resin cements (SAC-H and SAC-A, Kuraray Medical), one conventional resin cement (Panavia F2.0), t...

The aim of this study was to investigate the marginal accuracy of three currently used methods of direct provisional crown construction for the accuracy of marginal fit during in vitro fabrication. Three groups of provisional crowns were investigated using a modified McLean and von Fraunhofer technique. Proprietary provisional crown coping modified to tooth shape with a Bis-acryl temporary mate...

A resin-capture and release strategy for making combinatorial 2,6,9-trisubstituted purine libraries is demonstrated by capturing N9-derivatized purines at the C6 position with a thio-modified polymer. The C2 fluoro group is subsequently substituted with primary and secondary amines followed by thioether oxidation and release by C6 substitution with amines and anilines. This approach complements...