Identification of a resin-dentin hybrid layer in vital human dentin created in vivo: durable bonding to vital dentin.
The present study investigated the bond of 5% 4-methacryloxyethyl trimellitate anhydride in methyl methacrylate, initiated by partially oxidized tri-n-butyl borane in the presence of poly(methyl methacrylate) powder, to vital human dentin. In vivo dentinal substrates were pretreated for 10 or 30 seconds with an aqueous solution of 10% citric acid and 3% ferric chloride. Transmission electron microscopic examination of the bonded cross sections revealed the formation of a transitional, or "hybrid," layer of resin-reinforced dentin created by the impregnation, co-mingling and envelopment of collagen bundles, and encapsulation of hydroxylapatite crystals. The in vivo adhesion was assumed to be durable, because results of microscopic examinations were comparable to those of durable bonding of the same resin to extracted bovine dentin. Vital dentin exhibited greater resistance to demineralization by the acid solution than do extracted teeth. Carious extracted teeth were more easily dissolved in acid than were noncarious extracted teeth.
Nakabayashi
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N
Tokyo Medical and Dental University, Japan.
Ashizawa
M
M
Nakamura
M
M
D000180:Acrylic Resins / Q000737:chemistry*; D000268:Adhesiveness; D000269:Adhesives; D001896:Boron Compounds / Q000737:chemistry; D002712:Chlorides; D002951:Citrates; D019343:Citric Acid; D003094:Collagen / Q000737:chemistry; D003481:Cuspid; D001840:Dental Bonding / Q000379:methods*; D003731:Dental Caries; D003738:Dental Cements / Q000737:chemistry*; D003804:Dentin / Q000737:chemistry* / Q000648:ultrastructure; D017886:Durapatite; D005260:Female; D005290:Ferric Compounds; D006801:Humans; D006882:Hydroxyapatites / Q000737:chemistry; D007180:Incisor; D008297:Male; D008422:Materials Testing; D008689:Methacrylates; D008768:Methylmethacrylates; D008854:Microscopy, Electron; D008875:Middle Aged; D013499:Surface Properties; D013718:Tensile Strength; D017001:Tooth Demineralization
D000180:Acrylic Resins; D000269:Adhesives; D001896:Boron Compounds; D002712:Chlorides; D002951:Citrates; D003738:Dental Cements; D005290:Ferric Compounds; D006882:Hydroxyapatites; D008689:Methacrylates; D008768:Methylmethacrylates; C009523:tri-n-butylborane; D019343:Citric Acid; C031172:4-META resin; D003094:Collagen; D017886:Durapatite; C049495:Super-bond; C024555:ferric chloride