Presence of hyperplastic tissue such as flabby residual ridges, presents a great challenge in complete denture service. These redundant tissue are commonly removed surgically prior to denture making due to the difficulty of obtaining their accurate copies during impression making procedures.

A distortion of the impression of these structures is very likely due to the lack of underlying alveolar bone support as well as the inherent pressure exerted to it by the impression material and tray. These distortions in the impression significantly compromise the retention and stability of the complete denture prosthesis.

Surgical removal of these structure, however is not always the indicated treatment option. Window technique is considered to be an alternative to surgical intervention for such conditions. In conjunction with the concept of selective pressure impression making, window technique may provide a remarkable improvement in the accuracy and detail of the complete denture impression.