An In Vitro Study to Compare the Physical Changes and Retentive Forces in Three Different Implant Overdenture Attachments after Simulated Occlusal Loading

supported by implants, roots, or teeth. 17The use of two mandibular implants is now considered the standard of care. 18ISODs employ various mechanical attachments-ball/stud, bar-clip, magnetic, and telescopic, comprising a patrix (male) and matrix (female) element. 19ypically made of titanium, stainless steel, or polymers, these systems experience wear over time, reducing retention. 20Attachments are categorized by their permitted movement (PM-0 to PM-6). 21,22unctional variability, implant angulation, and occlusal forces can cause deviation from theoretical behavior. 23hile micromovement protects peri-implant bone, it increases matrix-patrix friction, leading to wear, more pronounced labiolingually. 24,25Mishandling during maintenance IntroductIonComplete edentulism is a debilitating, irreversible condition that profoundly impairs quality of life, representing the terminal phase of oral disease. 1 Despite global public health progress, it remains prevalent-particularly among older adults, affecting not only mastication but also speech, nutrition, self-esteem, and psychosocial well-being. 2,3Its persistence underscores disparities in healthcare access and socioeconomic conditions. 4Peltzer et al. 4 reported edentulism rates in those aged above 50 years as 18% in Russia, 16.3% in India, 9% in China, 21.7% in Mexico, and 8.5% in South Africa, while Switzerland showed only 5.7% prevalence. 5dentulism is multifactorial.While dental caries and periodontal disease remain primary causes, trauma, radiotherapy, genetics, and iatrogenic factors also contribute. 6Risk factors include diabetes, smoking, malnutrition (e.g., vitamin C deficiency), and low socioeconomic status. 7Periodontal disease now surpasses caries as the dominant cause. 8-10Consequently, prosthodontic rehabilitation is critical for restoring function and esthetics. 11Treatment modalities range from conventional dentures to implant-supported prostheses.While removable dentures are affordable and widely used, they often provide inadequate mandibular retention. 12mplant-supported overdentures (ISODs) offer improved retention, stability, and function at lower surgical and financial cost than fixed options.Studies 13-15 confirm their advantages in esthetics, mastication, speech, and quality of life.Additionally, ISODs distribute occlusal forces through implants, reducing bone resorption, especially in the mandible. 16An overdenture is a removable prosthesis