There are many variables involved. I did a great deal of research prior to starting and found a very experienced, educated dentist. I did all this because I am not just getting a few implants. I'm getting an entire upper denture which will have at least 7-8 implants and will only be taken out by the dentist to perform maintenance on the implants. I will not have to take it out; in fact, I won't be able to. Also, I am having a "snap-on" denture for the bottom. I will take it out once a day to maintain these implants. I just had 5 "locators" for the implants put in my lower jaw about 3 1/2 months ago. They are almost ready for the actual posts. Because of the extensive work and bone loss I had, I had sinus lift surgery in the upper jaw and bone grafted into the eye teeth area from my lower jaw when it was leveled. Altogether, I've had about 6 1/2 hours of what my dentist states is closer to orthopedic surgery than what is called dental surgery.
Obviously, you may not want or need all this. It depends on whether you need 1 or 2 implants or a whole jaw or a partial jaw. It depends on the location and whether there is bone loss. If you are getting a whole upper, you can have the roof plate of the upper denture removed so there is nothing on the roof of your mouth. There usually has to be a minimum of about 7-8 implants for this.
There are also mini-implants vs. regular and you will hear about immediate load. There is some disagreement over the use of the minis and immediate load. From my research and experience, if you are going to have many implants, no minis! They are less expensive but possibly not as permanent. Of course, the dentists that use them will argue otherwise. Immediate load is only if you have good bone and you are going to follow directions explicitly post implant.
If you have any other concerns or questions, I would be glad to answer. Oh, I had a "dream" anesthetic during both surgeries where I was only partially aware of what was going on. The sinus lift was not as bad as I had expected, but honestly, the second surgery was no picnic. However, I was back to normal within a week. When you have regular implants, these locators have to fuse with the bone and so it takes time to get the implants. Add bone grafting and waiting for the bone to form, and it is even longer. The upper takes longer than the lower jaw because it is a different type of bone. Who knew?
? In the upper jaw, I am at the point where I'm going to be fit for a denture so that bite and angulation and all the variables that make for a good bite and appearance in the upper jaw can be worked on. I will be having my second CAT scan for this. If you are having many implants, don't let them start without doing a 3D scan because of all the structures, including nerves, in your face/jaws.