A dental implant is artificial teeth that you may use as a way of replacing teeth that have fallen out or become decayed to the point of replacement. It would not affect the ordering of your teeth and you may replace as many teeth as you'd want with these implants.
Several people feel that the tooth won't look sufficiently natural so they don't even attempt to get the implants. The truth of the matter is that this implant does appear to be very natural and nobody will enable to see that the tooth isn't real. You might not even remember that you lost your tooth after a while!