Leah Walker Orthodontics at The Forum Carlsbad. Leah Walker Orthodontics, formerly known as Walker 3D Orthodontics, has been creating healthy, beautiful smiles for people of all ages in Carlsbad, Encinitas, San Marcos, Oceanside, and all around the La Costa area since 2006. She is known for her laid-back style and amazing results. As a doctor, she uses the latest technology to make orthodontics a breeze. As a Mom, she knows how to relate to kids and adults alike.