Background: Microstomia, defined as an abnormally small mouth opening, severely hinders essential daily functions such as eating, speaking, and maintaining oral hygiene. This condition can result from various causes, including surgical procedures, congenital defects, injuries, and connective tissue disorders such as oral submucous fibrosis (OSMF). Oral submucous fibrosis is a chronic, progressive disease characterized by fibroelastic changes and epithelial atrophy, leading to oral stiffness and restricted mouth opening. It is often associated with chewing tobacco, spicy foods, and nutritional deficiencies. Purpose: The primary objective was to enhance oral function and overall patient well-being in a completely edentulous patient with microstomia by addressing the physical limitations associated with denture use. This was achieved by providing innovative collapsible complete dentures designed in foldable sections for easier insertion and removal. Case: A 47-year-old woman diagnosed with OSMF and presenting with significantly limited mouth opening was successfully treated. Case Management: Innovative collapsible dentures were fabricated using a permanent silicone soft liner (MOLLOPLAST-B; Detax, Germany). This approach provided a comfortable and functional prosthetic solution that addressed the challenges associated with restricted mouth opening and altered oral tissues. The resilient nature of the permanent silicone soft liner acts as a shock absorber and conforms to the oral tissues, minimizing pressure points and facilitating prosthetic adaptation. Conclusion: This case report highlights the potential benefits of utilizing permanent soft liners in the management of microstomia associated with OSMF. This technique may represent a promising advancement in prosthetic dentistry for individuals with similar complex oral limitations.