Adhesive performance of a caries infiltrant on sound and demineralised enamel.
OBJECTIVE
Resin infiltration is considered as a treatment option for initial caries lesions. As cavitated early lesions might require additional restorative intervention, a caries infiltrant might be also used for enamel conditioning prior to composite insertion. This study aimed to analyse the shear bond strength of a flowable composite to sound and demineralised enamel pretreated with a caries infiltrant, a conventional adhesive or a combination of both.


METHODS
Flattened bovine enamel specimens (n=120) were either demineralised (14 d, acidic buffer, pH 5) or remained untreated. Sound and demineralised specimens (each n=20) were then treated with: (1) 35% phosphoric acid, conventional adhesive, (2) 15% hydrochloric acid, caries infiltrant or (3) 15% hydrochloric acid, caries infiltrant, conventional adhesive. Shear bond strength of a flowable composite was tested after 24 h water storage (37°C) and statistically analysed (ANOVA, p≤0.05). The mode of failure was assessed microscopically at 25× magnification.


RESULTS
On demineralised enamel, the combination of caries infiltrant and conventional adhesive showed significantly higher shear bond strength values than the conventional adhesive alone, while both being not significantly different from group 2. No significant differences between the groups could be detected on sound specimens. A higher percentage of cohesive failures could be observed in demineralised samples of group 2 (40%) and 3 (65%), while all other specimens presented almost only adhesive failures.


CONCLUSIONS
The use of a caries infiltrant before application of a conventional adhesive did not impair bonding to sound and demineralised enamel and might be beneficial as a pretreatment in demineralised enamel.
Wiegand
A
A
Department for Preventive Dentistry, Periodontology and Cariology, University of Zurich, Plattenstrasse 11, 8032 Zürich, Switzerland.
Stawarczyk
B
B
Kolakovic
M
M
Hämmerle
C H F
CH
Attin
T
T
Schmidlin
P R
PR
D000134:Acid Etching, Dental / Q000379:methods; D000179:Acrylates / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry; D000268:Adhesiveness; D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure*; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D000431:Ethanol / Q000737:chemistry; D006851:Hydrochloric Acid / Q000737:chemistry; D008422:Materials Testing; D010756:Phosphoric Acids / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D012997:Solvents / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D017001:Tooth Demineralization / Q000473:pathology*; D014867:Water / Q000737:chemistry
D000179:Acrylates; D000180:Acrylic Resins; D003188:Composite Resins; D003764:Dental Materials; D010756:Phosphoric Acids; D011109:Polymethacrylic Acids; D019279:Resin Cements; D012997:Solvents; C452226:tetric flow composite resin; D014867:Water; C020946:triethylene glycol dimethacrylate; D000431:Ethanol; D011092:Polyethylene Glycols; C040415:heliobond; C030242:phosphoric acid; D006851:Hydrochloric Acid