Retentive strength of metal copings on prefabricated abutments with five different cements.
BACKGROUND
Despite their wide use in implant dentistry, there is insufficient information concerning the retentive strength of cement-retained superstructures.


OBJECTIVE
This study compared the retentive strength of metal copings on prefabricated abutments with five different luting cements.


METHODS
Eight prefabricated abutments were placed on titanium screw implants torqued to 35 Ncm. Metal copings were cast with Au-Pt-Pd alloy (DeguDent Universal, Degussa, Hanau, Germany) using burnt-out plastic copings. Cements used were zinc oxide-eugenol-free temporary (ZO), zinc phosphate (ZP), glass ionomer (GI), resin-reinforced glass ionomer (RG), and composite resin (CR) cements. Retentive strength was measured with a universal testing machine. The means of each group were compared by one-way analysis of variance and Tukey-Kramer multiple-comparison intervals at a significance level of p < .05.


RESULTS
The mean +/- SD retentive strength of the cements in Newtons was ZO 56 +/- 12 (Tukey group C), ZP 158 +/- 79 (Tukey group B), GI 132 +/- 29 (Tukey group B), RG 477 +/- 52 (Tukey group A), and CR 478 +/- 50 (Tukey group A).


CONCLUSIONS
The retentive strength of metal copings on implant abutments is somewhat different from those of conventional cemented restorations on natural teeth. These differences may be influenced by differences in surface roughness and the height of the abutment.
Maeyama
Hideki
H
Division of Fixed Prosthodontics and Oral Rehabilitation, Nagasaki University Graduate School of Biomedical Sciences, Japan.
Sawase
Takashi
T
Jimbo
Ryo
R
Kamada
Koji
K
Suketa
Naoki
N
Fukui
Junichi
J
Atsuta
Mitsuru
M
D003188:Composite Resins / Q000737:chemistry; D000044:Dental Abutments; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry*; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D005899:Glass Ionomer Cements / Q000737:chemistry; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D010165:Palladium / Q000737:chemistry; D010984:Platinum / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D019415:Torque; D015034:Zinc Oxide / Q000737:chemistry; D015036:Zinc Phosphate Cement / Q000737:chemistry
D003188:Composite Resins; D003722:Dental Alloys; D003738:Dental Cements; D005899:Glass Ionomer Cements; D006047:Gold Alloys; D019279:Resin Cements; C449162:zinc oxide-non-eugenol cement; D010984:Platinum; D010165:Palladium; D015036:Zinc Phosphate Cement; D014025:Titanium; D015034:Zinc Oxide