Correction of retention deficiency in complete denture base

Denture retention is one of the most important denture aspects in an edentulous patient's satisfaction and treatment acceptance. It is related to prosthesis security during socialization as well as comfort during eating and speaking.^1,2 Complete denture retention relates to several physical and oral factors such as adhesion and cohesion forces, interstitial pressure, border seal, neuromuscular control and gravity.³ The posterior palatal seal (PSS) ‘is the soft tissue area at or beyond the junction of the hard and soft palates on which pressure, within physiological limits, can be applied by a denture to aid in retention’.⁴ PSS is particularly considered a prime factor for optimum maxillary denture retention, and its loss can significantly compromise the overall retention of the denture.³ Maxillary denture bases can become loose owing to acrylic shrinkage and base elevation in the mid-palatal region, leading to a loss of the PSS.⁵ This can be problematic with temporary bases during the critical stages of jaw-relation and try-in, as well as being disappointing with permanent bases when the denture is finally inserted.