In vitro evaluation of the implant abutment connection sealing capability of different implant systems

Abstract

This study sought to evaluate the sealing capability of the implant abutment connection of different dental implant systems. Five Nobel Replace select, Straumann and Intra-lock implants of approximately 4.5 mm diameter with their respective abutments were provided by the manufacturers. A calibration curve was determined by placing toluidine blue (TB) increments of 0.1 microL into 1.5 mL of distilled water and recording its absorbance in a spectrophotometer until reaching 0.7 microL. Then, 0.7 microL of TB was placed in the deepest portion of each implant's internal screw, the abutments were adapted to the implant according to the manufacturer's instructions and the specimens were placed in vials with 1.5 mL of distilled water. Spectrophotometric analysis was performed at 1, 3, 6, 24, 48, 72, 96 and 144 h. Statistical analysis was performed by One-way anova at 95% level of significance. The calibration curve was linear with respect to the TB amount in 1.5 microL distilled water (R(2) = 0.9961). All implant abutment systems presented an increase in absorbance as a function of time. As time elapsed in vitro, significantly higher amounts of TB was released from the Straumann and Nobel Replace Select connection systems (P < 0.0001). Leakage was significant between the groups. Despite controlled torquing, the seal between the implant body and the abutment could not be maintained in all three of the systems tested.

Evaluation of the Sealing Capability of the Internal Conical Connections of Implants with Titanium and Zirconia Abutments

“…Other researchers have not been able to maintain a seal with this tapered geometry. 17,18 After evaluating the interfaces of an implant system in which the titanium and zirconia abutments created an external butt joint with the implant platforms, Smith and Turkyilmaz 19 found that the titanium abutments showed a smaller microgap (ranged from 2.0 to 6.6 μm) compared with the zirconia abutments (ranged from 7.4 to 26.7 μm). Furthermore, they found that increasing the abutment screw torque from 20 to 35 Ncm significantly decreased the microgap at the zirconia abutment-implant interface (p = 0.017).…”

Evaluation of the marginal fit at implant–abutment interface by optical coherence tomography

“…Tight closure of the interface between the abutment and implant is critically important since an excessive level of gap could cause harm, such as plaque accumulation, difficulty to remove cement, and stress in the cervical area of the implant. [4][5][6] Additionally, microleakage produced by a gap between the components of implant restorations allows the passage of acids, enzymes, bacteria, and/or their metabolic products. 7 Several studies show that the bacteria are present on all surfaces; outside, between the implant components, and within them.…”

Bacterial microleakage at the implant-abutment interface in Morse taper implants

“…Even though these findings may be different in situations of mechanical load, inner joints are more stable and could be more beneficial, but few studies compared this situation 3,13 . Moreover, tests using dyes and bacterial toxins of molecular sizes, which are the real cause of marginal bone crest resorption, showed that microleakage occurs even in Morse tapered joints regarded as hermetically stable, and even in absence of load, its flow increases with time 8,11 . Therefore, more studies are required using bacteria, dyes and bacterial toxins under load conditions.…”

“…Two-piece implants have a microgap depending on the interface type or system, but presence of fluid flow at this interface and its relationships are very variable [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . This has been correlated to the presence of bacterial infiltration and inflammatory cells that may lead to bone loss around this area 19 .…”