With the development of virtual reality technology, surgery simulation has become an effective way to train the operation skills for surgeons. Soft tissue dissection, as one of the most frequently performed operations in surgery, is indispensable to an immersive and high fidelity surgery simulator. Energized dissection tools are much more commonly used than the traditional sharp scalpels for patient safety. Unfortunately, the interaction of such tools with the soft tissues has been largely ignored in the research of surgical simulators. In this paper, we have proposed an energized soft tissue dissection model. We categorize the soft tissues into three types (fascia, membrane and fat) and simulate their physical property accordingly. The dissection algorithm we propose employs an edge-based structure, which offers an effective mechanism for the generation of incisions dissected with energized tools. The mesh topology will not be changed when it is dissected by an energized tool, rather it is controlled by the heat transfer model. Our dissection method is highly compatible and efficient to the physically based simulation resolved by a pre-factorized linear system.