Direct numerical simulations (DNS) are used to test the previously predicted power law scalings of the source and sink terms in the equation for the flame surface area ratio. These scalings were derived from dimensional analysis based on two different regimes in premixed turbulent combustion where either kinematic restoration or scalar dissipation is the dominant sink term balancing the production of flame surface area. The DNS results show that the predicted square and cubic power laws are also valid if both destruction mechanisms are present and of comparable magnitude.