My implant fell out on holiday in Europe. Can I glue it back in myself?

The healing abutment should at least be as high as the tissue level.  If it is, when the blood clot dissolves, the tissue should heal normally.  If needed, a little tissue shaping with a laser can optimize results of the final restoration.  I'm sure your surgeon would be happy to...

R u  taking about crown colour? or gum colour?, its difficult to say anything without seeing your case so its my request to upload pic so i can guide u better.

20 years ago, it would have been far more difficult, if not impossible, to replace your missing teeth after three years, but thanks to modern dentistry you can have new teeth with dental implants that are just as strong as your natural teeth provided you have enough bone support. Even if you...