There are many implant systems used worldwide. I would advise you to discuss your concerns with your dentsit/implantologist that will be placing your implant. Ideally, you need to look for a system that is well recognized and one that has had independant research published for a number of years. This way, you can ensure that the system is reputable and has developed accordingly. Many of the newer systems do not use as high quality materials and do not have any studies to prove they have worked.
The following are some of the implant systems that are well recognised: Straumann, nobel biocare and Astra Tech.
Don’t be phased by this because whatever system the implantologist uses, he/she has obviously chosen that system because that is the system that they prefer and they have experience with. Hope this has helped and hope all goes well.