Efficacy of three types of impression materials in terms of retention of Maxillary complete denture

In intervention group, first a single step Sodium Alginate impression will be recorded in a stock tray. And then five minutes after that, a second impression with Condensation Silicone impressions material will be recorded in another stock tray. The size of the stock tray will be 3 mm wider than the edentulous maxillary ridges for both the impression materials. Both the impression materials will be mixed manually according to manufacturer's instructions and loaded in stock tray already selected. The patient will be seated in dental chair in an upright position. The maxillary arch height should be at elbow level of operator and operator will be standing at 11:00 Oclock position to the patient while recording impression. Each impression will be recorded by specialist prosthodontics ( Principal investigator having more than 13 years of experience in Prosthodontic specialty). After recording the impression, it will be verified by two other prosthodotnics specialists for acceptance of accuracy. If any of the two impression is considered unacceptable , the procedure will be repeated for that particular impression material . The thickness of set impression materials will be kept to 3 mm. These impressions will be poured and trial denture base (TDB) will be fabricated on the casts obtained from these two impressions. The retention of TDB will be compared with the controlled/comparator group. The time required to record impression for each procedure will be recorded in visits and minutes to complete the impression procedure.