Bonding Performance of Recent Self-etching Primer Systems to Cervical Tooth-substance

Objectives: To examine the bonding performance of recent typical self-etching primer systems to four types of cervical tooth-substance.
Methods: Four recent one-step self-etching primer systems; an experimental adhesive(XTE, 3M), Prime&Bond universal(PBU, Dentsply Sirona), Scotchbond Universal Adhesive(SBU, 3M) and Clearfil Universal Bond Quick(UBQ, Kuraray Noritake Dental), and a two-step self-etching primer system; Clearfil SE Bond 2(SE2, Kuraray Noritake Dental: as control) were used. The surface of cervical abrasion lesion dentin(ALD) of 40 extracted human premolars was cleaned with a low-speed rotated polishing-brush. The outer layer of cervical caries affected dentin(CAD) dyed by Caries Detector(Kuraray Noritake Dental) of 40 premolars was removed with a low-speed rotated round bur. Standardized V-shaped buccocervical cavity consisting of a gingival sound dentin-wall(SD) and an occlusal dentin-wall with beveled sound enamel(SE) was prepared in each 40 human intact premolars. The surfaces of ALD, CAD and both SD and SE(as control) were pretreated clinically with each system according to the manufacturer instructions. The immediate tensile bond strength(ITBS) of the systems to ALD, CAD, SD and SE were measured (n=8) with a custom-made portable adhesion tester. The data were examined using ANOVA, Tukey’s test, t-test and Weibull analysis.
Results: The mean ITBS (s.d.) in MPa to ALD/CAD/SD/SE were XTE; 26.5(8.2)/20.9(3.9)/29.0(8.8)/24.0(8.4),PBU; 22.1(6.0)/20.7(6.3)/26.7(5.9)/24.5(5.5), SBU; 23.2(5.8)/22.1(6.2)/26.5(5.9)/24.3(5.1), UBQ; 22.4(5.5)/22.5(6.8)/27.1(4.6)/24.9(5.3), SE2; 24.8(5.5)/20.6(6.9)/30.3(4.1)/30.7(8.1). The ITBS of SE2 to CAD was significantly smaller than the values to SD and SE at P<0.05. There were no significant differences in the ITBS of XTE, PBU, SBU and UBQ among the four types of tooth substance. No significant differences in the ITBS among five systems were recognized, regardless of tooth substance.
Conclusions: The bonding performances of four recent one-step self-etching primer systems(XTE, PBU, SBU,UBQ) were statistically similar to that of a two-step system(SE2) which was globally evaluated as a “golden-standard” system, regardless of tooth-substance type.