Sy. Lee et al., DETECTION OF LEACHED MOIETIES FROM DENTAL COMPOSITES IN FLUIDS SIMULATING FOOD AND SALIVA, Dental materials, 11(5-6), 1995, pp. 348-353
Objectives. The purpose of this study was to analyze the IR spectra of
a liquid simulating food and an artificial saliva following exposure
to resin composites. Methods. Fourier transform infrared (FTIR) spectr
oscopy was used to analyze two solutions in which three commercially a
vailable dental composites (Marathon One, Den-Mat Co.; Z100, 3M Co.; H
erculite XRV, Kerr Co.) were stored. The solutions used were: a food s
imulating fluid, 75 vol% ethanol/water, and an artificial saliva, Moi-
Stir (Kingwood Labs., Inc.). Specimens (4.3 mm diam, x 2 mm thick) of
the three resin composites were stored at 37 degrees C in 60 mt of eit
her Moi-Stir or the 75% ethanol solution for 7, 14, and 30 d. The FTIR
spectra were obtained using a liquid sample ATR (attenuated total ref
lection) cell. Results. No obvious leachable materials were seen from
any of the composite specimens stored in artificial saliva up to 30 d
of immersion. For the composites stored in ethanol, the observed spect
ra revealed increases in the principal absorption bands for the compon
ents of the three composite systems. Methacrylate skeletal vibrations
(1015-815 cm(-1)) and -CH3 alkane, C-H asymmetrical deformation vibrat
ions (1520-1460 cm(-1)) appeared after 14 d of storage. A very strong
peak characteristic of the aliphatic C=C moiety (1640 cm(-1)) and carb
onyl C=O (1730 cm(-1)) occurred after 14 d. The peak heights of these
two functional bands increased as a function of time and after 30 d of
storage were approximately 5-7 times those produced after 7 d. Irregu
lar O-H bands (3500-3300 cm(-1)) were also observed after 30 d in etha
nol. Significance. Irreversible processes such as the leaching of comp
onents occurs in the presence of ethanol. This phenomenon may contribu
te to irreversible material degradation.