start-ver=1.4
cd-journal=joma
no-vol=33
cd-vols=
no-issue=2
article-no=
start-page=196
end-page=202
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2008
dt-pub=20089
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Class I Gap-formation in Highly-viscous Glass-ionomer Restorations: Delayed vs Immediate Polishing
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=<p>This in vitro study evaluated the effects of delayed versus immediate polishing to permit maturation of interfacial gap-formation around highly viscous conventional glass-ionomer cement (HV-GIC) in Class I restorations, together with determining the associated mechanical properties. Cavity preparations were made on the occlusal surfaces of premolars. Three HV-GICs (Fuji IX GP, GlasIonomer FX-II and Ketac Molar) and one conventional glass-ionomer cement (C-GIC, Fuji II, as a control) were studied, with specimen subgroups (n=10) for each property measured. After polishing, either immediately (six minutes) after setting or after 24 hours storage, the restored teeth were sectioned in a mesiodistal direction through the center of the model Class I restorations. The presence or absence of interfacial-gaps was measured at 1000�~ magnification at 14 points (each 0.5-mm apart) along the cavity restoration interface (n=10; total points measured per group = 140). Marginal gaps were similarly measured in Teflon molds as swelling data, together with shear-bond-strength to enamel and dentin, flexural strength and moduli. For three HV-GICs and one C-GIC, significant differences (p<0.05) in gap-incidence were observed between polishing immediately and after one-day storage. In the former case, 80?100 gaps were found. In the latter case, only 9?21 gaps were observed. For all materials, their shear-bond-strengths, flexural strength and moduli increased significantly after 24-hour storage.</p>
en-copyright=
kn-copyright=

en-aut-name=IrieMasao
en-aut-sei=Irie
en-aut-mei=Masao
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=MaruoYukinori
en-aut-sei=Maruo
en-aut-mei=Yukinori
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=NishgawaGoro
en-aut-sei=Nishgawa
en-aut-mei=Goro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=SuzukiKazuomi
en-aut-sei=Suzuki
en-aut-mei=Kazuomi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=WattsDavid C
en-aut-sei=Watts
en-aut-mei=David C
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

affil-num=1
en-affil=
kn-affil=Okayama University

affil-num=2
en-affil=
kn-affil=Okayama University

affil-num=3
en-affil=
kn-affil=Okayama University

affil-num=4
en-affil=
kn-affil=Okayama University

affil-num=5
en-affil=
kn-affil=University of Manchester Dental School
END