“…Seven different indirect substrates were considered in this review. These included lithium disilicate ceramic, 20,22,23,25,28‐39 yttrium‐stabilized zirconium dioxide ceramic, 20 ‐22, 24,27,32,37,40‐53 leucite‐reinforced ceramic, 20,54‐56 feldspathic porcelain, 32,59 polymer infiltrated ceramic material, 19,58 resin composite, 20,26,29,57,59‐66 and metal alloys 67–69 . The characteristics of these studies are summarized in Table 2.…”