Solutions for severely angulated implants in the mandibular overdenture: a clinical report

Results of randomized clinical trials have confirmed that implant overdentures provide patients with better outcomes than do conventional complete dentures. Several designs have been introduced for the mandibular implant-retained removable prosthesis. The most commonly used prosthesis design for the mandibular overdenture is two implants in the canine areas with a stud attachment mechanism (i.e., ball attachments). This design is the least expensive, and therefore can service more patients and is now considered to be the "Standard of Care" for the mandibular edentulous patient. Proper treatment planning and execution lead to favorable implant placement and a successful prosthetic restoration and ultimately patient satisfaction; however, implant malposition may occur, which can lead to an unsuccessful prosthesis. This clinical report describes an implant overdenture design used for severely angled implants. Prosthodontic techniques that enabled this patient to have a successful outcome included the use of cast-to attachments and abutments along with a sectional matrix used to locate these components within the bulk of the prosthesis. For this patient the prosthodontic compromises were preferred over another surgical procedure with the additional time, discomfort, increased cost, and possible surgical morbidity. It is important that the patient understand the compromises and potential problems when implant placement is not ideal, especially the potential for implant overload and failure.