Effect of Cleansing Solutions on the Retention of Locator Attachments

Objectives: Locator-attachments ([LA], Zest, USA) are an alternative option for the retention of removable dental prostheses on teeth and dental implants. Colour coded males (polyamide) with different retention forces are provided by the manufacturer. Aim of this study was to evaluate changes in retention forces of different LAs after exposure to denture cleaners and mouthwash. Methods: Ten males of each LA (blue/pink/clear) were soaked for the equivalent of 12months of clinical use in 2 cleansing solutions (CoregaTabs-DentalWhite[DW], CoregaTabs-Partial[TD]), mouthwash (Cool-Mint-Listerine[L]) and aqua-dest.(control[C]). After thermal-cycling (n=5000/5°C/55°C) straight pull-off tests (n=20) of each male were recorded (universal testing machine, v=50mm/min, s=3mm). Resulting retention forces were electronically measured and descriptively and statistically analysed (t-Test, p<0.05). Results: LA's retention forces were significantly affected by DW:(8.90±1.9N [blue], 14.71±1.1N [pink], 24.34±3.6N [clear]), TD:(8.45±2.1N [blue], 13.43±2.5N [pink], 23.45±3.8N [clear]) and L:(6.50±2.9N [blue], 14.65±2.3N [pink], 22.48±1.9 [clear]) when compared to control (5.00±1.9N [blue], 11.17±2.4N [pink], 18.9±3.4N [clear]). Mouthwash also caused discolorations in all LAs. Conclusion: In this in-vitro study denture cleansing solutions caused an increase of the retention force of the tested Locator attachment males. Under clinical conditions retention may also be influenced by wear and fatigue stress.