What is the maximum length that can be increased of front two teeth via dental bonding? (photo)

A cosmetic bonding is a wonderful tool of filling cavities, closing gaps, cover up stains or even placing veneers to cover the facial surface of the tooth and make it look more even and uniform in color. The one limitation bondings have is the incisal edge, the tip of the tooth, that  has usuaally a wear pattern from grinding, thus they appear shorter. In case there is a small chip, a broken corner, an uneven edge, those can all be done with bonding. Increasing the length of the tip Is prone to failure, thus a few months of Invisalign is a much better option. 
And please wear your nightguard,
Dr. Goodman

Hi:The length of the two front teeth depends on the bite and clenching grinding habits.  Generally it should be 1-2 millimeter longer than the side front teeth.  Best,Dr. Maddahi