Retention of mandibular implant-retained overdentures with two different attachment designs: An in vitro study

Retentive force and loss of retention should be considered when selecting an attachment. Studies that evaluate the retentive force and the effect of repeated cycles of insertion and removal on the TITACH attachment with a metal-to-metal interface are needed.

The purpose of this in vitro study was to measure the retention of mandibular implant-retained overdentures with 2 different attachment designs before and after 1000 insertion and removal cycles.

Two dental implants were inserted at the mandibular canine region bilaterally in a completely edentulous model. Sixteen mandibular implant-assisted overdentures were fabricated to form 2 groups, each with a different attachment design. One group received 8 pairs of TITACH attachments, while the other group received 8 pairs of LOCATOR attachments. A cyclic loading machine was used to perform 1000 insertion and removal cycles. A universal testing machine was used to evaluate retentive force before and after insertion and removal cycles. Data were analyzed by using the Mann-Whitney U test and Wilcoxson signed-rank test.

When retentive forces before and after 1000 insertion and removal cycles were compared, the TITACH attachment showed significantly higher retentive force than the LOCATOR (P<.05). However, the LOCATOR attachment showed a significantly lower percentage change in retentive force (P<.05).

The TITACH attachment group showed favorable initial and final retentive force compared with the Zest Anchor LOCATOR attachment group. However, the LOCATOR attachment group showed favorable lower percentage change in retentive force.