This application is directed to methods of assessing polymer deposition on dental surfaces using near infrared spectroscopy, providing a rapid and efficient method to screen for and identify optimal polymers for use in oral care formulations, (i) near infra red (IR) absorption of a dental substrate is measured in the absence of a polymer under test, and subsequently of the test sample comprising the dental substrate contacted with the test polymer. After washing or rinsing the test sample near IR of it is determined again (iii). The IR absorption of the test polymer itself is also measured (ii). Through the comparison of the three measurements (i), (ii), and (iii) the degree of deposition and retention of the test polymer on the test sample is determined.