The purpose of the study was to correlate margin design(chamfer, shoulder, shoulder with a 45℃ bevel) with the seating and sealing of cemented full cast crowns under standardized simulated clinical conditions.
Wax patterns were mode with milled sta...
The purpose of the study was to correlate margin design(chamfer, shoulder, shoulder with a 45℃ bevel) with the seating and sealing of cemented full cast crowns under standardized simulated clinical conditions.
Wax patterns were mode with milled stainless-steel dies and rings, and were invested, burnt out, and cast, The full cast crowns were cemented on individual resin dies, and a gradually diminishing load(45㎏ to 25㎏) was applied over a 10-munite period. The specimens were sectioned centrally with a low speed saw and examined with a light microscope.
The results were as follows:
1. Chamfer preparations demonstrated it was the best marginal seal, followed in order by the shoulder with a 45° bevel, and by the shoulder(p<.05).
2. Chamfer preparations demonstrated it was the best occlusal seating, followed in order by the shoulder, and by the shoulder with a 45° bevel(p<.05).
J. Kyungpook Nat. Univ. Sch. Dent. Vol.8, No.1, 63∼73, 1991.