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How do supernovae affect the gas around H II regions?

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H II region Centre of the Orion Nebula (M42). Astronomers have identified some 700 young stars in this 2.5-light-year-wide area. They have also detected over 150 protoplanetary disks, or proplyds, which are believed to be embryonic solar systems that will eventually form planets. These stars and proplyds generate most of the nebula's light. This picture is a mosaic combining 45 images taken by the Hubble Space Telescope.

Supernovae significantly impact the gas surrounding H II regions by acting as a major source of disturbance and heating for the interstellar medium.1

The process typically unfolds as follows:

Creation of Hot Gas: Massive stars within an association generate powerful stellar winds that create cavities of hot, tenuous gas. Eventually, these massive stars reach the end of their lives and explode as supernovae, which further disrupt and heat the surrounding gas.1
Filling the Interstellar Medium: The hot component of the interstellar medium throughout the plane of the Milky Way Galaxy is largely produced and heated by these supernova explosions.1
Structural Impact: While H II regions are often characterized by a delicate tracery of luminous filaments, the surrounding space is filled with tenuous, million-degree material. This hot gas, generated by supernovae and stellar winds, helps separate the filaments of the denser, warm H II region gas.1

In essence, supernovae contribute to the constant state of turmoil and motion within these regions, helping to convert stellar energy into the kinetic energy of interstellar gas.12