The comparison of provisional luting agents and abutment surface roughness on the retention of provisional implant-supported crowns.
BACKGROUND
In immediate implant loading, it is important to keep provisional restorations in place during early-phase healing. Current luting agents for provisional restorations may provide inadequate retention, creating a clinical challenge.


OBJECTIVE
This study compared the retention of provisional autopolymerizing acrylic resin implant-supported single restorations with combinations of different implant abutment surface conditions and provisional luting agents.


METHODS
Thirty solid titanium implant abutments (ITI), 4 mm high, were divided into 3 groups. Ten abutments were unaltered, 10 were airborne-particle abraded with 50-microm aluminum oxide, and 10 were roughened with a medium-roughness diamond rotary cutting instrument. Thirty implant analogs (ITI) were mounted in autopolymerizing acrylic resin blocks. A solid titanium implant abutment was placed in each implant analog and torqued to 35 N.cm. After fabrication of 4 provisional acrylic resin crowns for each abutment, provisional luting agents TempBond, TempBond NE, Life, and Zone were used to secure the provisional crowns to the respective abutments. All specimens were luted with one of the provisional luting agents for a given test. After ultrasonic cleaning of the abutments, another provisional crown was luted with another luting agent. All specimens were stored in 100% humidity environment for 1 day at 37 degrees C prior to testing. Each provisional acrylic resin crown was pulled from the abutment with a 500-kg load cell in a universal testing machine at a crosshead speed of 0.5 cm/minute, and tensile strength was recorded (N). Data were analyzed using analysis of variance (ANOVA) and the Scheffe test (alpha=.05).


RESULTS
Tensile strength was significantly higher for Life and TempBond NE than for TempBond and Zone, regardless of the surface conditions (P=.0001). The result of the 2-way ANOVA indicated that a significant interaction existed between the provisional luting agents and surface conditions (P=.0039). TempBond NE showed significantly higher tensile strength when combined with airborne-particle-abraded surfaces compared to other combinations (P=.011). However, no difference was found in tensile strength of Life and Zone between different combinations. The tensile strength of TempBond was lower when used with the unaltered surface compared to other combinations (P=.001).


CONCLUSIONS
Surface modification of an implant abutment by airborne-particle abrasion or diamond rotary cutting instrument did not improve retention of a provisional acrylic crown when Life or Zone was used as the luting agent. Airborne-particle abrasion may be an effective method to increase retention of a provisional acrylic crown when TempBond NE is used.
Kim
Yongsik
Y
Department of Dentistry, University of Ulsan College of Medicine, Seoul, Korea.
Yamashita
Junro
J
Shotwell
Jeffrey L
JL
Chong
Kok-Heng
KH
Wang
Hom-Lay
HL
D000180:Acrylic Resins / Q000737:chemistry; D020906:Air Abrasion, Dental / Q000379:methods; D000537:Aluminum Oxide / Q000737:chemistry; D002126:Calcium Hydroxide / Q000737:chemistry; D003442:Crowns; D000044:Dental Abutments; D003738:Dental Cements / Q000737:chemistry*; D019250:Dental Implants, Single-Tooth; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D003794:Dental Restoration, Temporary; D018130:Diamond / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008899:Mineral Oil / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D014025:Titanium / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry
D000180:Acrylic Resins; D003738:Dental Cements; D003764:Dental Materials; C474196:Tempbond NE; C449162:zinc oxide-non-eugenol cement; D018130:Diamond; D008899:Mineral Oil; C040408:Life (dental material); D014025:Titanium; D000537:Aluminum Oxide; D002126:Calcium Hydroxide; D015034:Zinc Oxide