IADR Abstract Archives

Influence of Chemical Bonding Potential on the Adhesiveness of Glass-Ionomers

Chemical interaction between polyalkenoic acid and hydroxyapatite has been previously demonstrated (Yoshida et al., 2000). Furthermore, the molecular structure of polyalkenoic acids significantly influences their chemical interaction efficacy (Fukuda et al., 2003). Objectives: The aim of this work was to evaluate the influence of the molecular weight of two different polyalkenoic acids on the adhesiveness of a resin-modified glass-ionomer adhesive (FBLC: Fujibond LC, GC). Methods: As the chemical interaction of polyalkenoic acids may depend upon the amount of reactive carboxyl groups, experimental formulations with increasing molecular weights (5000, 8000, 15000 and 25000) of FBLC were specifically synthesized for this study. Influence of the molecular structure was also assessed by using polyalkenoic acids consisting of 100% acrylic acid units (PAA) and synthesized polyalkenoic acid co-polymers (s-PA) consisting of 90% w/w acrylic and 10% w/w maleic acid units. The micro-tensile bond strength (µTBS) to dentin of FBLC in combination with Gradia Direct (GC) was determined for 2 different surface treatments: no conditioning (NC) and after 25% polyalkenoic acid (synthesized with the same molecular weight and structure of the respective FBLC formulation, based on Cavity Conditioner, GC) conditioning for 10 s (CC). Additional interfaces were prepared for TEM ultrastructural analysis. Results:

µTBS: MPa±SD (n)

Commercial

exp-5000PAA

exp-8000PAA

exp-8000s-PA

exp-15000PAA

exp-15000s-PA

exp-25000PAA

NC

11.1±9.3a(11)4

4.2±6.2c,d(12)8

5.2±6.4c,d(12)6

5.5±6.7c(12)6

14.4±6.1a,e(12)1

11.6±3.2a(12)0

0.0±0.0d(12)12

CC

26.0±10.4b(15)0

0.6±1.9c,d(11)10

12.9±6.4a,e(12)2

12.7±5.3a,e(12)1

17.4±7.1e,f(12)0

22.8±6.4b(12)0

21.4±7.8b,f(10)0

Superscript letters indicate significant statistical difference (Kruskal-Wallis, p<0.05). Superscript numbers indicate pre-testing failures (0 MPa).

Interfacial analysis disclosed a hydroxyapatite-containing hybrid layer, but neither the absorption layer nor the gel phase were always distinguishable. Conclusions: Higher molecular weight is associated with enhanced adhesiveness, although possibly limited by the increasing viscosity in higher molecular weight formulations, particularly when surface treatments are not used.

This study was partially supported by CAPES Foundation and the Toshio Nakao Chair.

 


Continental European and Scandinavian Divisions Meeting
2005 Continental European and Scandinavian Divisions Meeting (Amsterdam, Netherlands)
Amsterdam, Netherlands
2005
2
Scientific Program
  • Coutinho, Eduardo  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • Van Landuyt, Kirsten  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • De Munck, Jan  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • Poitevin, André  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • Yoshida, Yasuhiro  ( Okayama University Graduate School of Medicine & Dentistry, Okayama, N/A, Japan )
  • Peumans, Marleen  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • Lambrechts, Paul  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
  • Van Meerbeek, B.  ( Katholieke Universiteit Leuven, Leuven, N/A, Belgium )
    • Oral Session
    Adhesion to Tooth Tissue I
    09/15/2005