Parafunctional habits, such as excessive clenching or grinding, create continuous mechanical irritation and trauma to the mucosal tissues beneath the denture. This repeated trauma disrupts the mucosal barrier, leading to inflammation and predisposes the area to infection by Candida species, resulting in denture stomatitis. Additionally, these habits increase mucosal pressure and microtrauma, impairing local blood flow and mucosal immunity, which are critical in the pathogenesis of this condition. Thus, controlling parafunctional habits is essential in preventing and managing denture stomatitis.

Reference: Oral Pathology, Neville et al., 4th Edition.