Crown deformation during cementation was measured with a circumferential strain gauge. The effects of different seating forces (3, 10 and 25 N), three different cements (Phosphacap, Ketac-cem Applicap and Fuji-cap I) and the presence or absence of venting on deformation and seating discrepancy were investigated. Forty mu m of cement space was provided for all experiments. Venting increased deformation and reduced seating discrepancy, whilst increased force increased deformation and decreased seating discrepancy. Ketac-cem Applicap allowed the lowest seating discrepancy with median crown deformation. It was possible, by using venting, low forces (10 N) and Ketac-cem Applicap, to achieve a low marginal discrepancy with low crown deformation. Venting also diminished the seating discrepancy to acceptable levels when higher forces (25 N) were used with Phosphacap.