Background: Edentulism results in decrease in size and tone of the pharyngeal musculature and may be an important risk factor for development of Obstructive Sleep Apnea (OSA). Epidemiological studies estimated that edentulism has been found to be present in about 18% of patients older than 60 years of age and that such prevalence would remain constant over the next 30 years. Considering the high prevalence of obstructive sleep apnea in the advanced age, it is conceivable that a consistent number of elderly people are at risk of edentulism induced worsening of obstructive sleep apnea and, consequently of morbidity and mortality due to this condition. Although cranio-mandibular abnormalities are well recognised risk factors for this manifestation, the role played by edentulism has never been investigated at length. The literature available on this issue was critically reviewed for the occurrence, etiology and prosthodontist's involvement in treating this condition Objective: The authors reviewed medical and dental literature dealing with edentulism and development of OSA and effect of complete denture/ oral appliances on the retropharyngeal space (smallest linear distance between anterior and posterior pharyngeal wall) and reduction in theincidence of OSA among apnea hypoapnea index (AHI). Results: Edentulous patients tends to be higher than that of the general population. Loss or absence of teeth produces prominent anatomical changes that may influence upper airway size and function, such as loss of the vertical dimension of occlusion resulting into reduction of height of the lower face and mandibular rotation. Rehabilitation of edentulous patients with complete dentures is an integral part of prosthodontic treatment. A denture not only provides aesthetics and improves the phonetics but also restores the desired function of mastication and also provides adequate support to oro-facial structures by restoring altered vertical dimension of face. Besides, it also improves OSA/hypopnea.