Strength of titanium-zirconium alloy implants with a conical connection after implantoplasty

Statement of problem.Peri-implantitis occurs around dental implants, and implantoplasty hasbeen used to address this ongoing disease; however, the changes to the physical properties ofan implant after implantoplasty have not been well documented. Purpose.The purpose of this in vitro study was to determine the effect of implantoplasty onfracture strength and the load required for plastic deformation after cyclic fatigue on dentalimplants. Material and methods.Twenty-six titanium/zirconium (TiZr) alloy implants (Roxolid Bone LevelImplant; 4.1x10 mm) were embedded with 50% thread exposure and divided into 4 groupsbased on whether they had implantoplasty treatment by using different diamond rotaryinstruments and/or cyclic loading at 250 N for 2 million cycles: C0 (control, no cyclic loading), T0(test, no cyclic loading), CM (control, cyclic loading), and TM (test, cyclic loading). Afterimplantoplasty and/or cyclic loading, all implants underwent a load-to-failure test. The maximumfracture strength (FS) and load required for the onset of plastic deformation (PD) were recordedin Newtons. One-way ANOVA and nonparametric comparisons with control by using the Dunnand Wilcoxon method for joint ranking were used for statistical analysis. Results.The mean +/- standard deviation FS for C0, CM, T0, and TM was 1465.2 +/- 86.4 N, 1480.7 +/- 64.1N, 1299.3 +/- 123.8 N, and 1252.1 +/- 85.7 N, respectively. The mean +/- standard deviation load for onsetof PD for C0, CM, T0, and TM was 860.2 +/- 88.1 N, 797.0 +/- 130.5 N, 776.5 +/- 181.8 N, and 631.3 +/- 84.5 N,respectively. The TM group had a significantly lower FS and PD than the C0, CM, and T0 groups(P<.05) Conclusions.Both fracture strength (FS) and the onset of plastic deformation (PD) weresignificantly reduced after a TiZr alloy implant received implantoplasty and cyclic loading. (JProsthet Dent 2024;132:593-9)