Evaluation of the retention of different types of attachments used in implant-retained overdenture prostheses based on time and denture cleanser

Retention in implant-retained overdenture prostheses is provided by attachments made of different materials with different morphologies and retention values. Attachments may be affected differently by daily cleaning procedures and their retention values may vary. The aim of this in vitro study was to investigate the effect of the routinely recommended Corega solution on the retention of different types of attachments after 1 year of clinical use. For this purpose, the abutments of the Locator and Novaloc systems were fixed to the implants and the nylon attachment of the Locator system and the PEEK retaining attachments of the Novaloc system were placed opposite them. In the study, 6 groups and a sample size of 8 were used. Group 1 was Locator blue (LM-C), group 2 was Locator pink (LP-C) and group 3 was Locator clear nylon attachment (LS-C); group 4 was Novaloc white (NB-C), group 5 was Novaloc yellow (NS-C) and group 6 was Novaloc green PEEK attachment (NY-C). After the test setup was prepared, the specimens were placed in the setup in sequence and the initial (T0) maximum dislodging forces were measured. Then, after 1080 insertion-removal cycles, which corresponds to 1 year of clinical use, the attachments were immersed in Corega solution for the 2nd time (T1) and finally for the 3rd time (T2). Analysis of Variance for repeated measures and Bonferroni multiple comparison test for pairwise comparison were used to analyze the obtained values. The change in T0, T1and T2 values over time was significant in all groups (p<0.001). In pairwise comparison, T0values were found to be different from T1 and T2 values (p<0.05), while there was no difference between T1 and T2 (p>0.05). NY-C was found to be the most changed group among the groups. Novaloc groups showed more force loss than Locator groups but were least affected by Corega solution. It was seen that Corega can be used safely in daily cleaning process.