Radiographic Outcomes Comparing Mini-Implant Versus Conventional Implant-Retained Overdenture with Different Attachment Systems: A Randomized Controlled Clinical Trial

This randomized controlled clinical trial aimed to evaluate and compare the radiographic outcomes of mandibular overdentures retained by mini-implants versus conventional implants utilizing different attachment systems. Twenty-one completely edentulous patients (aged 60-70 years) dissatisfied with conventional mandibular dentures were randomly and equally assigned into three groups. Group I received overdentures retained by four mini-implants (2.4 mm diameter, 13 mm length) placed in the interforaminal region; Group II received two conventional implants (3.7 mm diameter, 12 Any blinded information will be available then. mm length) with locator attachments bilaterally at the canine sites; and Group III received two conventional implants with ball-and-socket attachments in the same region. Cone-beam computed tomography (CBCT) was used to assess peri-implant marginal bone levels at baseline, 6 months, and 12 months post-insertion. Data were analyzed using non-parametric tests with a significance level set at p≤0.05. All groups demonstrated progressive bone loss over time. Group I exhibited the highest cumulative bone resorption (0.81±0.11 mm), significantly greater than Group II (0.41±0.16 mm) and Group III (0.45±0.21 mm) at 12 months (p=0.002). No significant differences were observed between Groups II and III. While all attachment systems maintained the bone levels within acceptable clinical limits, mini-implants were associated with greater marginal bone loss. Locator attachments on conventional implants exhibited the most favorable radiographic outcomes.