How Long Will It Take to Close a Gap Between Teeth of About 0,06 Inch (1,5 Mm)?

One challenge often overlooked is that gaps that formed once likely will open again unless retention efforts are performed.  This just means wear a retainer after braces/Invisalign.  

To close a 1.5 mm gap likely is only a matter of weeks, depending on the method.

Another way to avoid retainers is porcelain veneers.  This leaves the teeth where they are and fills in the spaces with tooth colored materials (porcelain or composite).  The investment may be more than braces, so a comprehensive consultation with an experienced cosmetic dentist is important.

Thank you for a great question.Invisalign moves teeth .25mm for each aligner. Assuming your case will permit 1 week aligner wear, it should not take more then 6 weeks to close gap between 2 teeth.The question should be asked though why is there such a big gap on the first place? What prevented teeth to have no space? If the reason for the space is gone, no problem, it will close smoothly. On the other hand, if the cause for the space is still there (like extra tissue between teeth), you might want to address that as well.

Invisalign is a great option to close gaps. If you only have the 1.5mm gap in your front teeth and everything else is perfect, you would probably need the aligners for only about 3 months. 
Warm Regards

Hi notordinary89,Invisalign makes precise small movements of up to .2mm for each aligner. However, this does not mean it will take just 8 aligners or 16 weeks to correct. If just these 2 teeth were moved, that would be the case. In reality, all the other teeth need to move to compensate, otherwise the gap would just be moved to the back of these teeth instead of the front.When you see a dentist or orthodontist for consultation, they should be able to give you an estimate of the expected time frame to complete treatment, but even then, it is only when a full computerised model of your teeth with a clincheck is carried out, that they can know with any certainty. Many practitioners of invisalign offer free consultation.It is more important to have correct treatment, than quick treatment. Good luck with your treatment.

Each person’s teeth move differently based on
their own biology. To close a gap of 1.5mm it would take 3 months on average.
Your individual treatment timing will be estimated based on a number of factors
including your bite, alignment of other teeth, and genetics.