This randomized clinical trial investigates the effect of two different attachment systems-Equator and Novaloc-on the retention, patient satisfaction, and oral health-related quality of life of mandibular implant overdentures. Completely edentulous patients often experience reduced denture stability, compromised chewing ability, and diminished oral function with conventional complete dentures. Implant-retained overdentures have been shown to improve retention, stability, and overall patient satisfaction. Equator attachments offer a small, resilient, and self-aligning system with variable retention levels, while Novaloc attachments feature innovative PEEK caps and a diamond-like carbon coating designed to reduce wear and maintain long-term retention. This study aims to determine whether one attachment system provides superior functional outcomes and patient-centered benefits, thereby guiding clinicians in optimizing overdenture therapy for edentulous patients."