The polymerizable dental isolation barrier has a monomer and an initiator. The barrier composition has at least one additive including a polymer strength reducer, a wet tissue adherence accentuator, and a reflective material The polymer strength reducer is an organic compound that prevents complete polymerization. The tissue adherence accentuator enables the barrier to adhere to a dental substrate ever after polymerization. The reflective material lowers the reaction rate and lowers the production of excess heat to reduce patient discomfort and to avoid tissue damage.