講演情報
[P-57（E）]Evaluation of factors affecting the retention of implant-supported PMMA restoration
*Ha-eun Choi1, Kyung-Ho Ko1, Yoon-Hyuk Huh1, Chan-Jin Park1, Lee-Ra Cho1 (1. Department of Prosthodontics, College of Dentistry, Gangneung-Wonju National University)
[Objective]
In implant prostheses, provisional restorations play a critical role in maintaining soft tissue contours, ensuring appropriate esthetics, and achieving successful outcomes. However, the prolonged use of provisional restorations often leads to frequent dislodgement. The purpose of this in vitro study was to evaluate the effect of treatment of intaglio surface of milled PMMA crowns in part 1 and abutment surface treatment and screw access hole (SAH) sealing methods in part 2.
[Method]
The provisional restoration specimens were designed in the form of maxillary first molars in a CAD program (exocad DentalCAD, Germany). The specimens were milled from PMMA blocks (Real Fit PMMA Block; HASEM, Korea) using milling machine (RainbowTM Mill; Dentium Co., Korea). A total of 133 specimens were cemented with temporary cement (Temp Bond NE, 3M ESPE). In part 1, the specimens were divided into three groups; 10-MDP group (10-MDP group), airborne-particle abraded with 50-um Al2O3 (APA group), and no surface treatment group (Control). In part 2, the specimens were divided into four groups according to whether the abutment was treated with APA or not and whether the SAH was sealed partially or fully. All specimens were subjected to 100,000 dynamic loading cycles at a rate of 2Hz with a load of 50N using a chewing simulator. The maximum tensile bond strength was then measured using a universal testing machine and the failure modes were analyzed.
[Results and Discussion]
Retention increased when the intaglio surface of crown was pre-treated by APA, but the effect was not significant. Retention significantly increased when the abutment surface was pre-treated by APA. Retention significantly increased when the SAH was sealed partially. The effect of abutment surface treatment was greater than that of SAH sealing method on milled PMMA retention.
[References]
1) Pitta J, Bijelic-Donova J, Burkhardt F, et al. Temporary Implant-Supported Single Crowns Using Titanium Base Abutments: An In Vitro Study on Bonding Stability and Pull-out Forces. Int J Prosthodont 2020;33:546-52.
2) Tan KM, Masri R, Driscoll CF, et al. Effect of axial wall modification on the retention of cement-retained, implant-supported crowns. J Prosthet Dent 2012;107:80-5.
In implant prostheses, provisional restorations play a critical role in maintaining soft tissue contours, ensuring appropriate esthetics, and achieving successful outcomes. However, the prolonged use of provisional restorations often leads to frequent dislodgement. The purpose of this in vitro study was to evaluate the effect of treatment of intaglio surface of milled PMMA crowns in part 1 and abutment surface treatment and screw access hole (SAH) sealing methods in part 2.
[Method]
The provisional restoration specimens were designed in the form of maxillary first molars in a CAD program (exocad DentalCAD, Germany). The specimens were milled from PMMA blocks (Real Fit PMMA Block; HASEM, Korea) using milling machine (RainbowTM Mill; Dentium Co., Korea). A total of 133 specimens were cemented with temporary cement (Temp Bond NE, 3M ESPE). In part 1, the specimens were divided into three groups; 10-MDP group (10-MDP group), airborne-particle abraded with 50-um Al2O3 (APA group), and no surface treatment group (Control). In part 2, the specimens were divided into four groups according to whether the abutment was treated with APA or not and whether the SAH was sealed partially or fully. All specimens were subjected to 100,000 dynamic loading cycles at a rate of 2Hz with a load of 50N using a chewing simulator. The maximum tensile bond strength was then measured using a universal testing machine and the failure modes were analyzed.
[Results and Discussion]
Retention increased when the intaglio surface of crown was pre-treated by APA, but the effect was not significant. Retention significantly increased when the abutment surface was pre-treated by APA. Retention significantly increased when the SAH was sealed partially. The effect of abutment surface treatment was greater than that of SAH sealing method on milled PMMA retention.
[References]
1) Pitta J, Bijelic-Donova J, Burkhardt F, et al. Temporary Implant-Supported Single Crowns Using Titanium Base Abutments: An In Vitro Study on Bonding Stability and Pull-out Forces. Int J Prosthodont 2020;33:546-52.
2) Tan KM, Masri R, Driscoll CF, et al. Effect of axial wall modification on the retention of cement-retained, implant-supported crowns. J Prosthet Dent 2012;107:80-5.
