GC EUROPE G-aenial Bond - Manual (Page 28)

28 G-ænial Bond Technical Manual
7.4 Quantitative marginal analysis
in order to assess the quality of restorations bonded with G-ænial Bond, using the self-etch and
selective etching (etch-and-rinse of enamel) techniques, quantitative marginal analyses were
conducted by Dr uwe Blunck - charité universitätsmedizin Berlin, for both class V and class i
restorations. (2008 & 2010)
Test set-up:
• Standardised Class V or I preparations were made in extracted human teeth stored in 0.5 % chloramine-T solution (8 per group).
• When relevant (etch-and-rinse technique), an etching agent was applied and rinsed off prior to use of the bonding systems.
the tested adhesive systems were applied according to the manufacturer’s instructions for use, and the preparations were
restored with the chosen composite(s) using an incremental technique.
• After finishing and polishing, the samples were stored in water for 21 days.
• Replicas were taken before and after thermocycling for the Class I and Class V restorations (2000 cycles between 5 and 55
°C), as well as after mechanical occlusal loading for the Class I restorations (150.000 cycles at 49 N).
• The margins of the restorations at the enamel- and/ or dentine-composite interface(s) were examined and quantified with a
scanning electron microscope (Sem) at a magnification of x200, using defined criteria (table 6) to assess the quality of the margins.
table 6: criteria for the marginal assessment in the Sem at x200 magnification
margin-quality Definition
1 margin not visible or barely visible. no, or slight, marginal irregularities. no gap
2 no gap but severe marginal irregularities
3 Gap visible (hairline crack up to 2 µm). no marginal irregularities
4 Severe gap (more than 2 µm). Slight and severe marginal irregularities
the term "marginal irregularities" means:
- porosities
- marginal restoration fracture
- bulge in the restoration
Figure 24: Sem of marginal adaptation in dentine (left) and enamel (right), margin quality 1 (original magnification: x200) after
TC (white bar = 100 μm). Source: Adapted excerpt from Dr U. Blunck, Charité Universitätsmedizin Berlin, Germany, 2008
7.4.1 marginal analysis of class V restorations after thermocycling
Tests performed by Dr Uwe Blunck, Charité Universitätsmedizin Berlin
the purpose of the following studies was to evaluate the effectiveness of GBa 400 (commercially available
as G-ænial Bond) adhesive in class V composite resin restorations that had margins in dentine and in
enamel. the marginal behaviour of the restorations, which were filled using an incremental technique, was
evaluated before thermocycling and then after thermocycling in order to simulate clinical conditions.
dentin
composite
composite
enamel