Effects of polar solvents and adhesive resin on the denaturation temperatures of demineralised dentine matrices.
OBJECTIVE
To measure the denaturation temperature (Td) of demineralised dentine matrix as a function of infiltration with water vs. polar solvents vs. adhesive resins.


METHODS
Small discs of normal dentine were completely demineralised in 0.5M EDTA. Dried demineralised specimens were placed in water, methanol, ethanol, acetone, eta-butanol or HEMA. Additional specimens were infiltrated with Prime&Bond NT and polymerised. All specimens sealed in high-pressure pans and scanned using differential scanning calorimetry (DSC).


RESULTS
Demineralised dentine saturated with water showed a Td of 65.6 degrees C that increased with saturation by methanol, ethanol, acetone, eta-butanol or HEMA to 148.5 degrees C. These increases in Td were inversely related to the molar concentration of the solvents and to their Hoy's solubility parameter for hydrogen bonding (delta h, p<0.01), as well as directly related to the cube root of their molecular weights (p<0.001). The presence of adhesive resins also increased the Td of demineralised matrices to even higher values depending if the resin bonded dentine was measured after 24h of water storage (166.8 degrees C) or dry (172.7 degrees C) storage.


CONCLUSIONS
Solvents and monomers with low delta(h) values (i.e., 100% HEMA) increase the Td of demineralised dentine above that produced by solvents with higher delta h values such as methanol and water.
Armstrong
Steven R
SR
University of Iowa, Iowa City, IA 52242-1001, USA.
Jessop
Julie L P
JL
Winn
Erik
E
Tay
Franklin R
FR
Pashley
David H
DH
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D003094:Collagen / Q000187:drug effects; D003804:Dentin / Q000737:chemistry / Q000187:drug effects*; D006801:Humans; D008963:Molar / Q000187:drug effects; D011109:Polymethacrylic Acids / Q000494:pharmacology*; D012997:Solvents / Q000494:pharmacology*; D018709:Statistics, Nonparametric; D013696:Temperature; D017001:Tooth Demineralization / Q000188:drug therapy*
D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D012997:Solvents; D003094:Collagen