Microleakage of occlusoproximal adhesive restorations, effect of dentin moisture after acid etching.
OBJECTIVE
The aim of this study was to evaluate the effect of dentin moisture after acid-etching on marginal sealing in occluso-proximal composite restorations.


METHODS
Ninety occluso-proximal preparations were made in posterior teeth with gingival margin in dentin. Prepared teeth were divided in 3 groups (N=30) according to the type of solvent of adhesive (ethanol/water=SB, Single Bond 3M ESPE, acetone=PB, Prime & Bond NT Dentsply, and ethanol=OP, OptiBond Solo Plus, Kerr). And 3 subgroups (N=10) according to the types of treatment of the cavity after rinsing the acid etchant ( 1) cavity air-dried for 10 s at a distance of 1 cm; 2) cavity blot-dried with slightly moist cotton pellets; 3) cavity with visible excess of water). Hybrid composite was applied in four increments. After 24 hours, teeth were thermocycled (500 cycles, 30 s, 5 to 55 masculineC) and immersed in 0.5% basic fucsin for 4 hours. The teeth were cleaned, dried and sectioned. The microleakage extent was analyzed with a 0-5 scale in dentin margin. Enamel margins were verified for presence or absence of microleakage. Data were submitted to Kruskal Wallis test (P<0.05).


RESULTS
The median of microleakage scores in dentin margins were: SB_a=1, SB_b=0, SB_c=1, PB_a=1, PB_b=1, PB_c=2, OP_a=0, OP_b=1, OP_c=1. Considering bonding systems, PB provided more microleakage than SB and OP (P=0.0316). In groups where cavity had visible excess of water there was higher microleakage degree than the dry cavity subgroups (P=0.048). In enamel margins, median was 0 for all groups.


CONCLUSIONS
Better marginal sealing is obtained in dentin margins of occluso-proximal cavities when they are air-dried or blot-dried with cotton pellets after acid-etching.
Carpena Lopes
G
G
Department of Operative Dentistry, Federal University of Santa Catarina, Florianópolis, Brazil. guilhermelopes@ccs.ufsc.br
Colle Zanette
A
A
D000134:Acid Etching, Dental; D001641:Bicuspid; D001834:Body Water; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003763:Dental Leakage / Q000209:etiology / Q000517:prevention & control*; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008963:Molar; D011897:Random Allocation; D016369:Smear Layer; D012997:Solvents / Q000494:pharmacology; D013499:Surface Properties
D003188:Composite Resins; C444701:Filtek Z250; D012997:Solvents