Access to the pulp chamber for endodontic treatment is indicated inter alia as a result of extensive caries, trauma to the tooth causing fracture or loss of vitality, requiring restoration of the missing tooth structure. Different approaches and materials are described in the literature for foundation restorations, either with a cast post and core or immediately, with a chairside post-and-core system. This article briefly reviews the current data regarding the microbiologic, prosthetic, mechanical, and periodontal aspects while emphasizing the immediate approach using amalgam, resin composites, and glass ionomers. Factors affecting retention of the post are presented to guide the clinician in selecting a suitable post-and-core system to preserve optimal root structure and prevent root fracture. Three clinical cases are presented in which tooth structure was restored using different techniques: in the first two, provisional acrylic resin shells, one custom made and the other prefabricated, were used to house an amalgam coronal-radicular dowel core, where in the third case, a copper band was used for a composite post-and-core system. All cases emphasize the ease of production and short chairtime in the stages of crown fabrication.