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

PURPOSE: To evaluate and compare the radiographic outcomes of mandibular overdentures retained by mini-implants versus conventional implants using different attachment systems.

MATERIALS AND

METHODS

Twenty-one completely edentulous patients (aged 60 to 70 years) who were dissatisfied with conventional mandibular dentures were randomly and equally assigned into three groups. Group I received overdentures retained by four mini-implants (2.4 × 13 mm) placed in the interforaminal region; Group II received two conventional implants (3.7 × 12 mm) with locator attachments bilaterally in the canine sites; and Group III received two conventional implants with ball-and-socket attachments bilaterally in the canine sites. CBCT was used to assess peri-implant marginal bone levels at baseline and at 6 and 12 months after placement. Data were analyzed using nonparametric tests with a significance level set at P ≤ .05.

RESULTS

All groups demonstrated progressive bone loss over time. At 12 months, 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) (P = .002). No significant differences were observed between Groups II and III.

CONCLUSIONS

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.