The increase in demand for metal-free implant-supported prosthesis led to the development of new esthetic and biocompatible dental materials used as frameworks. The All-on-four implant-supported complete denture framework can be fabricated from a variety of materials. Traditionally framework material was cast from noble metal (gold) or base metal alloys (i.e Chromium-cobalt) veneered with heat-cured acrylic resin The advent of Computer Assisted Design (CAD) and Computer Assisted Milling (CAM) allowed milling of a substructure free from defects and distortions, passively fitting on the implant platform.
