Comparative Evaluation of color stability and optical properties of PET, PETG and TPU based aligner materials: an in vivo study

This is a prospective, randomised double blind study of three aligner materials PET, PETG and TPU on 5 patients of each material which includes students and patients visiting in the department of orthodontics from Sudha Rustagi College of Dental Sciences willing for orthodontic treatment. Samples of each material will be taken and thermoformed using thermoforming machine. Two sets of aligners need to be fabricated at the start of the study. One set is sent for study and one is delivered to the patient. Optical properties of each aligner, in terms of absorbance/transmittance will be obtained, using FTIR spectrophotometer before delivering the aligners to the patient. For each material we will carry out tests at interval of 7 days and 14 days after wear. At 7th day of aligner wear, the aligners will be collected from the patient, washed with distilled water and immediately sent for the tests. An additional aligner of the same series or another set of series will be delivered to the patient to replace the aligner collected for test purposes. Similar methodology will be used for 14th day.