[Bonding and mechanical interlocking of three kinds of luting cements in retention of complete metal crowns].
OBJECTIVE
To evaluate the effects of bonding and mechanical interlocking of three kinds of luting cements in the retention of complete metal crowns.


METHODS
Zinc phosphate cement (ZP), glass ionomer cement (GI) and polycarboxylate cement (PC) are in common use for clinical treatment. In this study, these cements were selected to bond the complete crowns to molars in vitro. The retention capacities of the complete crowns were tested and compared. And apart from mechanical interlocking, the effect of bonding was tested. On this basis the interlocking capacity of the cement was calculated.


RESULTS
1. The retention capacities of complete metal crowns from the highest to least were: GI > ZP > PC. 2. The proportions of mechanical interlocking of ZP, GI and PC in the retention of complete metal crowns were 62.6%, 48.3% and 20.1% and the ratios of bonding of ZP, GI and PC were 37.4%, 51.7% and 79.9%, respectively.


CONCLUSIONS
The effects varied with different cements in the retention of complete metal crowns because of the discrepancy in bonding and mechanical interlocking properties. Mechanical interlocking plays a prominent role when ZP or GI is used, and the role of bonding is apparent in PC.
Chen
X
X
Department of Prosthetics, School of Stomatology, WCUMS, Chengdu 610041, China.
Wang
J
J
Sun
J
J
D000269:Adhesives; D003442:Crowns; D001840:Dental Bonding; D003738:Dental Cements; D017268:Dental Prosthesis Retention; D005899:Glass Ionomer Cements; D006801:Humans; D013314:Stress, Mechanical
D000269:Adhesives; D003738:Dental Cements; D005899:Glass Ionomer Cements