Which muscle has dual function related to complete denture?

The masseteric notch in the distobuccal area of the denture base accommodates the mesial border of the masseter muscle. The masseter influences the denture base at this point during both opening and closing movements of the mandible. Overextension will result both in tis­sue soreness and in movement of the denture base. When the masseter muscle contracts under heavy closing pressures, it reduces the size of the space available for the distal end of the buccal flange. The extent of the buccal vestibule can be deceiving because the coronoid process obscures it when the mouth is opened wide. Therefore it should be examined with the mouth as nearly closed as possible. This space usually is more superior than any other part of the border. Key Concept: Masseter is known as the muscle performing dual functions.