Invisalign can treat predominantly modest to medium dental conditions (as previously described) which would be improved or resolved using a teeth alignment appliance and braces are often used to treat more complex cases. It is an orthodontic treatment option designed just to straighten teeth to create a perfect smile as opposed to a tooth preservation or tooth replacement technique used in general dentistry. Invisalign braces might not be suitable if your orthodontist feels that conventional braces are likely to be more effective.