Influence of the time-point of salivary contamination on dentin shear bond strength of 3 dentin adhesive systems.
OBJECTIVE
The aim of this study was to evaluate the influence of the duration of salivary contamination at different stages during the bonding procedures on shear bond strengths (SBS) of 3 dentin adhesives.


METHODS
Flat human dentin surfaces were produced by wet grinding on SiC paper 800. The adhesives used were Syntac Sprint (SS) (Vivadent), One Step (OS) (Bisco), Clearfil Liner Bond 2 (LB2) (Kuraray). Three durations of contamination (3 s, 10 s, and 20 s) at 3 stages (before adhesive application, after its application, and after its polymerization). In all cases the saliva was not rinsed off. Twenty-seven groups of 10 samples were studied according to 3 adhesives, 3 stages, and 3 durations of contamination. For each adhesive, 1 control group, 3 groups with contamination before adhesive application, 3 groups with salivary contamination on the uncured adhesive, and 3 groups with contamination after polymerization (except for SS) were studied. Composite cylinders (Z100, 3M; 3 mm Ø, 5 mm high) were polymerized on the surfaces and stored in 37 degrees C H2O for 48 hours prior to shear bond testing (v = 5 mm/min).


RESULTS
Anova and Scheffe tests showed that for the one-bottle systems tested, salivary contamination prior to adhesive application had no adverse effect on bonding efficacy, SBS decreased significantly when saliva contamination occurred after adhesive application. The self-etching primer tested was more tolerant to salivary contamination, except when the salivary contamination occurred before the polymerization of the adhesive.


CONCLUSIONS
Salivary contamination does not have the same influence at different stages of the bonding process with modern adhesives. Pending better knowledge of the mechanisms involved in the influence of salivary contamination on bonded assemblies, it seems necessary to continue to recommend using the rubber dam in adhesive dentistry.
Hitmi
L
L
Department of Biomaterials, Groupe de Recherche Biomatériaux, Faculté de Chirurgie Dentaire, Université Paris V, 1 Rue Maurice Arnoux, F-92120, Montrouge, France. hitmi@odontologie.paris-5.fr
Attal
J P
JP
Degrange
M
M
D000179:Acrylates; D000704:Analysis of Variance; D003188:Composite Resins; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008298:Maleates; D008422:Materials Testing; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D008963:Molar; D016062:Porosity; D012463:Saliva / Q000737:chemistry*; D012471:Salivary Proteins and Peptides / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors
D000179:Acrylates; C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; C112274:Clearfil Liner Bond 2; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D008298:Maleates; D008689:Methacrylates; D012471:Salivary Proteins and Peptides; C443859:Syntac Sprint