A study on light transmittance through red protective shields modified with different window films

OBJECTIVES/AIMS: This study aimed to improve effectiveness of red protective shields in filtering unwanted light using window films. MATERIALS AND METHODS: Red protective shields were modified by placing V-Kool (VK), Scotchtint (ST) or Hüper Optik (HP) window films on both sides. Percentage transmittance (%T) of light with a wavelength of 190–990 nm was determined using a double-beam ultraviolet (UV) and visible spectrophotometer. RESULTS: In UV light (190–390 nm) and visible light (430–590 nm) ranges, %T in all modified groups and the control was below 2.5%. An increase in %T was observed at the wavelength of 630 nm, when all the modified shields showed superior effectiveness in light filtration over the control. In the infrared spectrum (700–990 nm), %T in the control was constantly high, ranging from 86 to 91%, compared to %T of 2–38% in all the modified groups, with the application of VK on both sides being the most effective group, followed by a combination of VK and HP. CONCLUSION: This study has introduced an economical and simple, yet highly effective, means of enhancing the efficiency of a red plastic protection shield in filtering unwanted infrared light, thereby additionally providing protection for dental personnel from potential ocular damages.