Effects of bioactive additions on the physical properties of glass polyalkenoate cement

Aim Conventional glass ionomer cements are clinically attractive materials and have unique properties that make them useful dental restorative materials. The glass ionomer cements however are slightly brittle materials though they deform a little under load. They display high compressive strengths but slightly weak flexural strengths. Collagen type I and RGD peptides (Arg-Gly-Asp) are the most effective and widely used bioactive molecules to promote cell adhesion on a synthetic surface. This study investigates the effect of chairside addition of bioactive molecules (Collagen type I and RGD) into glass polyalkenoate cement on improving the physical properties.

Materials and methods Mechanical properties of the glass polyalkenoate cement (ChemFil Superior, Dentsply De Trey, Konstanz, Germany) were investigated both at baseline and after incorporating bioactive additions made at the time of mixing the material. The properties that are of potential significance for clinical durability were determined namely; compressive strength, diametral compressive strength, three-point flexural strength, diametral compressive fatigue limit, and biaxial flexural strength. Results: Additions of Type I Collagen and RGD to ChemFil Superior improved all physical properties measured except shear bond strength where no detriment was observed.

Conclusion Chairside additions of bioactive molecules to conventional glass ionomer restorations have potential clinical applications and represent a new paradigm in dentistry that can be utilized to improve biocompatibility, mechanical properties, and therefore, clinical durability. Improving the mechanical strength of glass ionomer restorations by optimized reinforcement strategy requires further investigation. Clinical significance: the methodology of mixing conventional glass ionomer with bioactive molecules for superior biocompatibility and reinforcement, developed in the present study, should be applicable to chairside dental procedures. The increase in physical properties of the glass polyalkenoate, achieved in the present study, may help extend its dental applications to the restoration of stress-bearing cavities.