When a business is making headway in a massive and uncontested global market, shareholders reap the benefits. The result could well be a run of wild growth over the next few years. Align Technology's (NASDAQ: ALGN) business model is simple: It sells its Invisalign tooth straighteners to dentists and orthodontists, who use its scanning and 3D modeling devices to adapt the straighteners to fit their patients -- thus eliminating the need to get traditional braces.