Generally speaking, a slight underbite in many people can potentially be addressed in a few different ways. First, there is traditionaly orthodontic treatment. As you indicated that braces were not something you wanted to deal with again, you may want to consider the Invisalign system. It is a a system that uses a clear splint to move your teeth into position. You may also get the results you are looking for from porcelain veneers. They are thin shells of porcelain that are bonded to your teeth to give the effect of perfectly straight teeth. These can usually be applied over the course of a few weeks. If you are interested in this procedure, I would go to www.aacd.com, which is the website of the American Academy of Cosmetic Dentistry, to obtain the name of an accredited cosmetic dentist in your area. Good luck!