What Type of Retainer Should I Use After Closing my 5mm Diastema with Invisalign?

A 5 mm diastema is difficult to keep together in the best of cases.  I like Vivera retainers from Invisalign but would also add a metal retainer at the back of our upper teeth to help keep the space closed.  

Retention is a must, meaning wearing a removable retainer for at least a part of each day, usually at night.  As mentioned, a metal or ceramic fixed retainer placed on the back of the front anteriors ensures complaince.  The teeth will only stayed closed as long as a retainer is regularly worn for the rest of your life and hence the fixed retainer on the back of these teeth may be preferred.

With a 5 mm diastema there is a strong relapse potential; even if you wear a clear Invisalign type retainer there will be a tendency for the space to open up if you wear the retainer less than full time.  To prevent this, a small metal bar bonded on the tongue side of the two front teeth is the preferred retainer ... in addition to the clear plastic one worn at night.  One potential problem with this type of retianer is if the lower teeth contact the back side of the upper front teeth in a "deep bite" or "overbite" type of way there may not be any room for the bonded retainer.  Hopefully Invisalign has successfully reduced the overbite so this is not an issue.