Microleakage of the Interface between Implant and Abutment of Five Different Implant Systems during a Five-year Simulation of Dynamic Loading in a Chewing Simulator

Microleakage of the Interface between Implant and Abutment of Five Different Implant Systems during a Five-year Simulation of Dynamic Loading in a Chewing Simulator
L. STEINEBRUNNER, S. WOLFART, K. B?Ò?¸MANN, K. LUDWIG, and M. KERN, UNIVERSITY HOSPITAL Schleswig-Holstein, Kiel, Germany
2003
IADR
Objectives: Microbial leakage and bacterial colonisation of the inner part of implants might clinical cause inflammatory reactions in the peri-implant tissues. To analyze this, microbial leakage at the implant-abutment-interfaces of two well known and three recently developed implant systems was tested during dynamic loading in a chewing simulator. It was suggested, that the dynamic loading will decrease the stability of the implant-abutment connections and thereby increase microleakage at the interfaces. Methods: Standard implant-abutment combinations with a 4.5 to 5 mm diameter for single-tooth-restorations in the molar region were tested for the Br?ïnemark-System (NobelBiocare, S-G??teborg), the Frialit-2/Hermetics System (Friadent, D-Mannheim), the Replace-Select-System (NobelBiocare, S-G??teborg), the Camlog-System (Altatec, D-Wurmberg) and the Screw-Vent-System (Centerpulse Dental, USA-Carlsbad) with eight samples of each system. Each abutment was restored with a simplified single crown, which was luted with a composite resin (Panavia 21, Kuraray, J-Osaka). Then, under sterile conditions, the inner part of the implant was inoculated with 5¨µl Escherichia coli suspension and thereafter attached to it's superstructure with a transocclusal screw following the manufacturer's instructions. Afterwards the samples were mounted into a chewing simulator (Willytec, D-Munich) and immersed in a nutrient solution (CASO-Bouillon, Merck, D-Darmstadt). The restorations were loaded with 1,200,000 cycles of 120N in the chewing simulator. Microbial leakage of the specimens was tested by checking the nutrient solution for bacterial contamination at regular intervals. When microbial leakage was detected, the accomplished chewing cycles were recorded. Statistical analyses were performed with the Kruskal-Wallis test (p¨£0.05) followed by the Mann-Whitney test modified by Bonferroni-Holm. Results: All specimens showed bacterial leakage. The median chewing cycles until bacterial leakage occurred were: 172,800(Br), 43,200(Fr), 64,800(Re), 345,600(Ca), analyses in process (Sc). Statistically significant differences were found between group Fr and Ca. Conclusion: Current implant-systems cannot reliably prevent microbial leakage and bacterial colonisation at the implant-abutment-interface under mechanical loading.