Evaluation of Retention and Attachment Wear of CAD/CAM Versus Conventional Implant-Assisted Overdenture Frameworks

Previous studies have demonstrated problems with implant-supported overdenture attachments, such as denture base fracture and retention loss of the attachment's nylon insert. In this study, three implants were surgically inserted at the anterior mandibular region of 16 completely edentulous men (mean age: 50 years), divided into two groups depending on the received mandibular complete overdenture: a conventional metal-reinforced framework with prefabricated metal housing (Group I) or a CAD/CAM metal-reinforced framework with custom metal housing (Group II). At 3 months (prostheses loading), 6 months, and 12 months after implant placement, the retention of the mandibular dentures and wear of O-ring attachments were evaluated. Data were collected, tabulated, and statistically analyzed using Student t test. Statistically significant differences were found between the two groups and within the same groups during the evaluation period (P < .05). Attachment housing incorporated within a CAD/CAM implant overdenture can be a better alternative to the manufacturer's metal housing, as it diminishes retention loss and attachment wear over time, thus increasing patient satisfaction and chewing efficiency.