A dental wedge for inserting into the interproximal space between adjacent teeth comprises a first and second sidewall comprised of a shape memory material, including a nickel-titanium alloy, wherein the dental wedge is in a first, resting state when outside of the interproximal space and transforms to a second, operational state when the dental wedge is interested into the interproximal space between adjacent teeth and exposed to a first transformation stimulus, namely exposure to the higher temperature in the interproximal space. The expansion force generated by the dental wedge when in the second, operational stage is sufficient to secure a dental matrix against the tooth being restored and to separate the tooth being restored and adjacent tooth to expand the interproximal space.