UNCORRECTED PROOF VSP 2001/04/20 Prn:12/10/2004; 13:08 {RA} F:jast2505.tex; VTeX/ p. 1 (48-131) J. Adhesion Sci. Technol., Vol. 00, No. 0, pp. 1–15 (2004)  VSP 2004. Also available online - www.vsppub.com The effect of hyper-branched polymers on the properties of dental composites and adhesives H. DODIUK-KENIG 1,2,∗ , K. LIZENBOIM 2 , I. EPPELBAUM 2 , B. ZALSMAN 2 and S. KENIG 1 1 Shenkar College for Engineering and Design 12 Anna Frank St., Ramat-Gan 52526, Israel 2 BJM Laboratories Ltd., 12 Hassadna St., Industrial Park, Or-Yehuda 60200, Israel Received in final form 27 September 2004 Abstract—With the emergence of commercial hyper-branched (HB) and dendritic polymers, having a three-dimensional (3D) morphology with high peripheral functionality, new opportunities have been created for formulating dental adhesives and composites with enhanced mechanical and physical properties. The objective of the present study was to investigate the properties obtained by incorporating HB and dendritic polymers into acrylate-based dental composite and adhesive systems. Four commercial HB polymers were evaluated: Polyamidoamine dendrimer, two dendripolyamides and HB polyesteramide. These were added to dental restorative glass filled prepolymers, based on BisGMA, HEMA and TEGDMA. The dendritic and HB polymers blended readily with the prepolymers. A significant effect of HB polyesteramide (HB1), addition (0.1–3.0 wt%) on the mechanical properties was shown. It was found that addition of 0.3 wt% (optimal value) of HB polyesteramide raised the compressive strength from 253 ± 20 MPa to 386 ± 20 MPa and lowered the linear shrinkage from 2.4 ± 0.2% to 1.5 ± 0.2 % (for a model dental composite formulation). It was shown that the HB polyesteramide added to the dental adhesive compositions increased the shear bond strength and enhanced the bond durability to a variety of dental surfaces. Keywords: Dental adhesives; dental composites; hyper-branched polymers; compressive strength; linear shrinkage. 1. INTRODUCTION Amalgams have been used for dental restoration since the early 19th century and are still part of everyday dental practice [1]. The main challenge in dental restoration is to mimick and enhance the amalgam’s dimensional stability and strength using polymer systems. Nevertheless, polymer ∗ To whom correspondence should be addressed. Tel.: (972-3) 6110-000/257. Fax: (972-3) 619- 0013. E-mail: hannad@mail.shenkar.ac.il