DHI Medical Group has treated more than 250,000 hair loss sufferers over the past 50 years. The learnings of all these years have been built into the only set of quality control protocols for Hair Restoration called the TOTAL CARE SYSTEMTM. The Direct Method of Hair Transplants. The company’s legacy dates back to 1970 in Palo Alto in California where the first clinic was founded. Over the past 52 years, DHI Medical Group has dedicated itself to a single goal of innovating and delivering the best solutions in hair restoration to hair loss sufferers around the world. DHI has been awarded both US and EU patents.