There are a variety of injectable fillers, which vary in terms of thickness and elasticity.  Dr. Wenzel will offer several options and his preference based on your goals and lip anatomy.   Fillers usually last 12-18 months in terms of noticeable change.  The effects are visible the day of the procedure.  Nerve blocks similar to those used during dental procedures are used to reduce the pain associated with the procedure and most patients say with the technique there is minimal discomfort.