Engelsk titel: Marginal gap formation in approximal “bulk fill” resin composite restorations after artificial ageing
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Författare:
Peutzfeldt, Anne
;
Mühlebach, Sarah
;
Lussi, Adrian
;
Flury, Simon
Email: anne.peutzfeldt@zmk.unibe.ch
Språk: Dan
Antal referenser: 46
Dokumenttyp:
Artikel
;
Jämförande studie
UI-nummer: 18070035
Sammanfattning
AIM – The aim of this in vitro study was to investigate the
marginal gap formation of a packable regular resin composite
(Filtek Supreme XTE) and two flowable bulk fill resin
composites (Filtek Bulk Fill and SDR) along the approximal
margins of Class II restorations.
MATERIAL AND METHODS – In each of 39 extracted human molars
(n = 13 per resin composite), mesial and distal Class II cavities
were prepared, placing the gingival margins below the
cemento-enamel junction. The cavities were restored with
the adhesive system OptiBond FL and one of the three resin
composites. After restoration, each molar was cut in half in
the oro-vestibular direction between the two restorations,
resulting in two specimens per molar. Polyvinylsiloxane impressions
were taken and baseline replicas were produced.
The specimens were then divided into two groups: At the
beginning of each month during six months’ tap water storage
(37°C), one specimen per molar was subjected to toothbrushing,
whereas the other was subjected to thermocycling.
After artificial ageing, final replicas were produced. Baseline
and final replicas were examined under the scanning electron
microscope (SEM), and the SEM micrographs were used
to determine the percentage of marginal gap formation in
enamel or dentin. Paramarginal gaps were registered. The
percentages of marginal gap formation were statistically analyzed
with a nonparametric analysis of variance followed
by Wilcoxon-Mann-Whitney tests and Wilcoxon’s signed rank
tests, and all P-values were corrected with the BonferroniHolm
adjustment for multiple testing (significance level: ɑ =
0.05). Paramarginal gaps were analyzed descriptively.
RESULTS – In enamel, significantly lower marginal gap formation
was found for Filtek Supreme XTE compared to Filtek
Bulk Fill (P = 0.0052) and SDR (P = 0.0289), with no significant
difference between Filtek Bulk Fill and SDR (P = 0.4072). In
dentin, significantly lower marginal gap formation was found
for SDR compared to Filtek Supreme XTE (P < 0.0001) and
Filtek Bulk Fill (P = 0.0015), with no significant difference
between Filtek Supreme XTE and Filtek Bulk Fill (P = 0.4919).
Marginal gap formation in dentin was significantly lower than
in enamel (P < 0.0001). The percentage of restorations with
paramarginal gaps varied between 0% and 85%, and for
all three resin composites the percentages were markedly
higher after artificial ageing.
CONCLUSIONS – The results from this study suggest that in
terms of marginal gap formation in enamel, packable resin
composites may be superior to flowable bulk fill resin composites,
while in dentin some flowable bulk fill resin composites
may be superior to packable ones.