ELASTIC-MODULI AND VISCOELASTIC RELAXATION

The elastic moduli of dental biomaterials are discussed in relation to the various intrinsic and extrinsic factors that can influence the ma gnitude of these parameters and hence the extent of modulus-matching w ith oral tissues. The time-dependent visco-elastic response is shown t o be an important feature of both natural and many synthetic biomateri als. This modifies the stress magnitudes sustained in the restored uni t, especially when polymeric chains or networks are a major constituen t of the overall structure. An understanding of both moduli and visco- elasticity is valuable in the appraisal of clinical performance of bio materials.