Minnie,
I would say that I have rarely seen swelling or bruising after implant placement. However, that means that it can happen. Much depends on the skill of the surgeon and also how well you follow directions. I'm sure there will be a list of do's and dont's. Every practitioner has their own suggestions, so if you follow what's recommended, you should be fine.
Are you having immediate placements, i.e. are they doing the extractions and implant placement at the same time? The more that's done at one sitting, obviously increases the chances of swelling, but if possible, this cuts down alot of time waiting for the teeth.
Jerry