Geometric comparison of five interchangeable implant prosthetic retaining screws.
Eight geometric parameters of five interchangeable prosthetic retaining screws (#1-3i Implant Innovation-gold, #2-Impla-Med-gold, #3-Nobelpharma-gold, #4-3i Implant Innovation-titanium, and #5-Implant Support Systems-titanium) were recorded with an Amray 1000-B scanning electron microscope at x20 to x200 magnification. Five screws of each type were measured and eight parameters were evaluated: (A) diameter of head, (B) screw length, (C) thread pitch, (D) major diameter, (E) neck diameter (F) length of neck, (G) crest width, and (H) root width. The Nobelpharma-gold prosthetic retaining screws served as controls. The results revealed significant differences between the control and test screws in all parameters except parameters C and G (ANOVA, p < 0.05) and Duncan's multiple range test (significance level 0.05). On the basis of these differences, it was concluded that interchanging prosthetic retaining screws can introduce unknown variables in treating patients.
Department of Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor.
M J
MJ
Jaarda
M E
ME
Razzoog
D G
DG
Gratton
D000704:Analysis of Variance; D017267:Dental Prosthesis Design / Q000592:standards*; D017268:Dental Prosthesis Retention / Q000295:instrumentation* / Q000592:standards; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D006801:Humans; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties