Retention of Metal Reinforced Polyamide Denture Base and Heat Cured Acrylic Resin Denture Base in Complete Mandibular Denture

Inclusion Criteria: 1. Male or female patient with age range from fifty five to sixty five completely edentulous and in good medical condition 2. Patients have skeletal Angle's class I maxillo-mandibular relationship and sufficient inter arch distance. 3. Free from any systemic or neuromuscular disorder that might affect chewing efficiency of masticatory muscles. 4. Free from any tempro-mandibular disease. 5. Good oral hygiene. Exclusion Criteria: 1. Neuromuscular disorder and orofacial disease. 2. Tempromandibular joint and muscle pain 3. xerostomia or excessive salivation. 4. Limited mouth opening