Sienna Modern Dentistry and Orthodontics Share: Dentists Sienna Modern Dentistry and Orthodontics Visit Website 8740 Hwy 6., Ste 150 Missouri City, Texas 77459 (281) 778-5355 About Map About Dentists serving the Missouri City area on the southwest corner of Hwy 6 & Sienna Pkwy, in the Sienna Plantation Shopping Center, near the HEB. What's Nearby? Distance: 5 10 15 20 25 50 mi.