Effect of Denture Cleansing Solutions on the Retention of Locator Attachments Over Time

To evaluate and compare the alterations in retention of three Locator attachments after immersion in various denture cleansers at defined time intervals.

Two implants were embedded in an acrylic block. Pink, blue, and clear Locator attachments (n = 10 for each subgroup) were immersed into three different cleansing solutions (Corega, Protefix and NaOCl) and tap water (control) at different time intervals that simulate 1 (T₁ ), 6 (T₂ ), and 12 (T₃ ) months of clinical use. Universal testing machine set at a crosshead speed of 50 mm/min was used for pull-out tests. After the immersion procedure, the peak force to dislodgement was recorded to demonstrate the changes in retention of Locator attachments. Data were analyzed using repeated-measures ANOVA followed by Tukey's Honestly Significant Difference (HSD) tests (α = .05).

All denture cleansing solutions affected the retentive values of all Locator attachments at defined time intervals (F = 4.299, p = 0.001). NaOCl affected all groups significantly after 12-month immersion time (p = 0.001). The least retention loss at all subgroups was observed in Corega for clear Locator attachments (106.17 ± 5.21 N). The difference in retention values for pink attachments were not statistically significant for tap water, Protefix and Corega immersion at all time intervals (p > 0.05). Following NaOCl (blue; 33.31 ± 4.72 N, clear; 52.3 ± 8.5 N), tap water decreased the retention value of blue (41.14 ± 3.93 N) and clear (76.72 ± 8.42 N) Locator attachments at T₃ . Corega caused the least retention loss to clear attachments at T₁ (106.17 ± 3.55 N).

The retention of Locator attachments decreases over time after exposure to various denture cleansing solutions. As NaOCl significantly decreased the retentive values of all attachments, patients must be informed about that disadvantage. Also, tap water remarkably decreased retentive ability of all attachments. Periodic addition of an effervescent tablet into tap water may be recommended to patients that wear implant retained overdentures with Locator attachments.