The purpose of this paper is to describe the subgingival placement of a resin-ionomer for several restorative procedures, namely, root resorption, endodontic perforation, and root fracture. After endodontic therapy, a combination scallop flap (in attached gingiva)-full thickness flap (at affected tooth only) was raised to gain access to the lesion and root defect. The root defects were prepared with ultra-sonic instruments under an operating microscope and the preparations treated with Tenure Dentin Conditioner (DenMat Corporation, Santa Maria, CA). The preparations were washed and lightly air-dried, and the Tenure All-Purpose Bonding System (Den Mat Corporation, Santa Maria, CA) was placed in the prepared areas. Geristore resin-ionomer (DenMat Corporation, Santa Maria, CA) was then syringed into the preparations and either light-activated or allowed to undergo a chemical set. Once set, the material was finished with fine diamonds under water spray. The flap was then sutured to place with Gore-Tex sutures when a non-resorbable Gore-Tex membrane (Gore Corporation, Flagstaff, AZ) was used or 4-0 nylon sutures when resorbable Guidor membranes (Butler Company, Bensenville, IL) were used. The sutures were removed after two days. The patients were observed weekly for the first month and then monthly until released. No untoward effects have been observed during the time frame of this project. All of the cases have been responding satisfactorily. CONCLUSIONS The cases presented indicate that a resin ionomer, Geristore, may be used as a subgingival restorative, and may be placed in lesions thought to be unrestorable. Thus, teeth may be saved that were previously designated to be extracted.