We analyzed bubble rupture and hole opening dynamics in a non-Newtonian fluid by investigating the retraction process of thin films after inflation at different blowing rates. The experiments were modeled through a dimensional analysis, with the aim of establishing a general approach on the bubble rupture dynamics and discerning the role of viscous, elastic, surface, and inertial forces on the opening velocity, according to the nature of the specific fluid. A new mathematical model, which includes all possible contributions to the hole opening dynamics, was proposed, to the best of our knowledge for the first time. The experimental evidence on the opening velocity as a function of the inflation rate was found to be in good agreement with the prediction of the model. The sensitivity of our modeling was tested by comparing our results with the existing models of retracting velocity.