Provided herein are composite materials comprising a thiol-ene polymer resin in a continuous phase and a filler in a discontinuous phase, the filler comprising fluorapatite crystals and silica. Further provided are methods of using these composite materials as restoratives in dental applications. This dental composite is labeled as “smart” because, when the shrinkage stress of the composite is greater than a programmable or pre-selected threshold level, it will elicit visual clues for the dentist.