title: Post retention and post/core shear bond strength of four post systems.
abstract: As clinicians we continue to search for a post system which will give us maximum retention while maximizing resistance to root fracture. The introduction of several new post systems, with claims of high retentive and resistance to root fracture values, require that independent studies be performed to evaluate these claims. This study tested the tensile and shear dislodgment forces of four post designs that were luted into roots 10 mm apical of the CEJ. The Para Post Plus (P1) is a parallel-sided, passive design; the Para Post XT (P2) is a combination active/passive design; the Flexi-Post (F1) and the Flexi-Flange (F2) are active post designs. All systems tested were stainless steel. This study compared the test results of the four post designs for tensile and shear dislodgment. All mounted samples were loaded in tension until failure occurred. The tensile load was applied parallel to the long axis of the root, while the shear load was applied at 450 to the long axis of the root. The Flexi-Post (F1) was significantly different from the other three in the tensile test, however, the Para Post XT (P2) was significantly different to the other three in the shear test and had a better probability for survival in the Kaplan-Meier survival function test. Based on the results of this study, our recommendation is for the Para Post XT (P2).
authors.affiliation: Faculty of Dentistry, Department of Restorative Dentistry, The University of Manitoba, D227-780 Bannatyne Ave, Winnipeg, Manitoba, Canada R3E OW 2.
authors.forename: L W
authors.initials: LW
authors.lastname: Stockton
authors.forename: P T
authors.initials: PT
authors.lastname: Williams
authors.forename: C T
authors.initials: CT
authors.lastname: Clarke
mesh_terms: D000134:Acid Etching, Dental; D000704:Analysis of Variance; D002484:Cementation; D003188:Composite Resins; D001840:Dental Bonding; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D006801:Humans; D016018:Least-Squares Analysis; D011176:Post and Core Technique / Q000145:classification; D011336:Probability; D019279:Resin Cements; D013193:Stainless Steel; D013314:Stress, Mechanical; D013499:Surface Properties; D016019:Survival Analysis; D013718:Tensile Strength; D019237:Tooth Cervix; D014082:Tooth Fractures / Q000517:prevention & control; D014092:Tooth Root / Q000293:injuries
chemical_list: D003188:Composite Resins; D019279:Resin Cements; D013193:Stainless Steel