Have no fear, dentistry will be around for a long time to come. First off, you're assuming that there will be 100% compliance with this multiple time per year "vaccination". How many folks actually finish a prescription thats given to them, not alot! <img border="0" alt="[Wowie]" title="" src="graemlins/wowie.gif" /> Now, the huge factor, will insurance companies cover the vaccine, because if they don't, alot of folks won't take it. Here is insurance company rationale as to will they or won't they cover, what will the cost of the vaccine be per year patient verses what will the cost of a restoration or 2. I'll almost guarentee that when they look at all their insured folks and figure the average of how much restorative work they'd pay out per year that it will be less than the cost of vaccinating their members. Therefore, the insurance companies will be SLOW to get onboard, and thus alot of folks won't pay for it out of their pockets.
Now, even if the vaccine does get insurance approval, there are currently just in the US, BILLIONS of existing restorations that will need to be replaced at some point

There are also the folks that only come into the office every few years when they have something that bothers them (can you say root canal, build up and crown $$$)

Then there will undoubtedly be the folks that think that the vaccine is harmful and won't take it (see the anti flouridation folks about this one) This doesn't even get into the already mentioned restorative/cosmetic needs, perio treatments, ortho treatment, etc, etc, etc. Rest assured, dentistry will continue to thrive long past the time that anyone who is even considering entering school now has retired from practice
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