Dental General dfeab386 Best range of UV light used for treatment of skin diseases A 100 – 200 nm B 200 – 400 nm C 400 – 700 nm D > 700 nm High-Yield Explanation UV light most commonly used in dermatology are UVB (290 - 320 mn), narrow band UVB (311 nm), and UVAi (360 - 380 nm).