THE JOURNAL OF - Dentsply

Frankenberger et al
Table 1 Overview of materials under investigation
Adhesive +
resin composite
XP BOND/SCA +
Calibra
Syntac
(with Calibra)
OptiBond FL
(with Calibra)
Components
Etchant: 36% phosphoric acid
Primer/Bond: TCB resin, PENTA, UDMA, TEG-DMA, BHT, CQ, functionalized
nanofiller; mixed with SCA (self-curing activator)
Luting composite:
Base: bis-GMA, EBPADM, silica, UDMA, TEG-MA, butylhydoxitoluol, barium
glass, silica
Catalyst: bis-GMA, EBPADM, silica, UDMA, TEG-MA, butylhydoxitoluol, benzoyl
peroxide, barium glass, silica
Etchant: 35% phosphoric acid
Primer: maleic acid 4%, TEG-DMA, water, acetone
Adhesive (2nd primer): water, PEG-DMA, glutaraldehyde
Heliobond: bis-GMA, UDMA, TEG-DMA
Luting composite: see above
Etchant: 37.5% phosphoric acid
Primer: HEMA, GPDM, MMEP, ethanol, water, initiators
Adhesive: bis-GMA, HEMA, GPDM, barium-aluminum borosilicate glass,
disodium hexafluorosilicate, fumed silica (total=48% filler)
Luting composite: see above
Manufacturer
Dentsply DeTrey; Konstanz,
Germany
Ivoclar Vivadent; Schaan,
Liechtenstein
Kerr; Orange, CA, USA
for luting of Class I resin composite inlays after different
contaminations, temporary cement removal, and curing
modes. The null hypothesis was twofold, that (1) different
adhesives with different curing modes, and (2) different
temporary cements and cleaning methods would have no
influence on dentin bond strength beneath adhesively luted
inlays.
MATERIALS AND METHODS
Ninety-six intact, noncarious, unrestored human third molars
were stored in an aqueous solution of 0.5% chlora
mine T at 4°C for up to 30 days. The teeth were debrided of
residual plaque and calculus, and examined to ensure that
they were free of defects under a light microscope at 20X
magnification. Standardized Class I cavity preparations (4
mm in width and length, 3 mm in depth) were performed.
Cavities were cut using coarse diamond burs under profuse
water cooling (80 μm, Two-Striper Prep-Set, Premier; St Paul,
MN, USA), and finished with a 25-μm finishing diamond. Inner
angles of the cavities were rounded and the margins
were not bevelled. To guarantee a rectangular relation between
the bonded interface and the direction of the later-cut
μTBS beam, the cusps were flattened by 2 mm and then the
cavity floor was prepared parallel to the flattened cusps.
Direct resin composite inlays (Clearfil AP-X, Kuraray;
Tokyo, Japan) were manufactured under isolation of the cavities
with glycerine gel. The inlays received a cubic shape
with the surface being parallel to the bottom of the cavity to
facilitate positioning of the light-curing tip. The bottom sides
of the inlays were sandblasted with aluminum oxide (Rondoflex
27 μm, KaVo; Biberach, Germany), washed with 70%
ethanol, and dried. The prepared teeth received provisional
restorations (Fermit N, Ivoclar Vivadent; Schaan, Liechtenstein),
and were stored in distilled water at 37°C for one
week. The provisional restorations were either inserted with
or without two different temporary cements (Temp Bond /
Temp Bond NE, Kerr; Orange, CA, USA). Two more groups
with hybridizing dentin prior to temporizing were also made,
either with one coat of adhesive (immediate dentin sealing 17
[IDS]) or with one 0.5-mm layer of flowable resin composite
(X-Flow, Dentsply DeTrey; Konstanz, Germany) (resin coating
technique 13 [RC]). Here, temporary cements were omitted
because they play no role in bonding to dentin.
After removing Fermit, cement remnants were removed
with a scaler or using different air-polishing powders (Prophypearls
Powder, KaVo; ClinPro Prophy Powder, 3M ESPE;
Seefeld, Germany), both operating in a Prophyflex air-polishing
device (KaVo) at the level of the occlusal cavity margin
for 10 s. 2 After rinsing with tap water and drying, the cavities
were treated with different adhesives and one luting
composite (Table 1). Internal surfaces of the resin composite
inlays were silanized with Monobond S (Ivoclar Vivadent),
dried, and covered with the respective adhesive, which was
not light cured. Adhesives and luting resin composite were
polymerized with a Translux CL light-curing unit (Heraeus
Kulzer; Dormagen, Germany). The intensity of the light was
checked periodically with a radiometer (Demetron Research;
Danbury, CT, USA) to ensure that 600 mW/cm 2 was always
exceeded during the experiments. Adhesives were light
cured for 40 s in the case where the protocol advised it. Oth-
270 The Journal of Adhesive Dentistry