Implant/abutment vertical misfit of one-piece cast frameworks made with different materials

Abstract

This study compared vertical and passive fit of one-piece cast frameworks made with 3 different materials: commercially pure titanium (CP Ti - G1), cobalt-chromium alloy (Co-Cr - G2) and nickel-chromium-titanium alloy (Ni-Cr-Ti - G3). Fifteen frameworks were obtained simulating bars for fixed prosthesis in a model with 5 implants. The passive and vertical fit of the framework interface was measured using an optical microscope at x30 magnification. Data were statistically analyzed by ANOVA and LSD tests (α=0.05). Mean and standard deviation values for passive fit and vertical fit were, respectively: G1 [472.49 (109.88) µm and 29.9 (13.24) µm], G2 [584.84 (120.20) µm and 27.05 (10.30) µm], and G3 [462.70 (179.18) µm and 24.95 (11.14) µm]. For vertical fit, there were no significant differences among G1, G2 and G3 (p=0.285). There were no significant differences for passive fit between G1 and G3 (p=0.844), but both differed significantly from G2 (p=0.028 and p=0.035, respectively), which showed the highest misfit values. It may be concluded that the vertical fit of frameworks was not affected by the tested materials, and that one-piece cast frameworks resulted in inadequate passive fit. The Co-Cr alloy presented the worst values for passive fit.

Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant–abutment connection

“…These complications have a multifactorial etiology [3–5]. Current studies indicate that position stability of the implant–abutment connection (IAC) is a decisive factor for prosthesis misfit [6, 7] and mechanical complications [8]. Position stability of the implant–abutment connection is essential, since multiple repositioning of the implant components is necessary during fabrication of the superstructure by the dental technician and the dentist [9, 10].…”

Technical complications with implant-supported dental prostheses

“…This is in disagreement with findings reported in the literature that state that discrepancies in the fit between a prosthesis and abutment can be overcome by the use of a bonding agent, thereby conferring greater stability to the set of components (17). It should be stressed that the abovementioned studies are laboratory studies (13,18) and bonding in such cases is performed under ideal, pre-established conditions. A number of factors can affect the bonding of prostheses on both teeth and implants, such as the preparation of the abutment, the taper of the abutment, surface area, surface roughness, type of cement and experience of the dentist (19).…”

A new portable vibrator for plaster pouring: effect on the marginal fit at cylinder-abutment

“…According to literature 1,4,12 the marginal misfit can be influenced by the technique 1 and by the material 4,12 used to fabricate the frameworks. However, this research suggests that the vibration is also an important factor at this point, reminding that it refers to just one of many steps that are required to get a prosthetic piece.…”