Clinical versus laboratory adhesive performance to wet and dry demineralized primary dentin.
OBJECTIVE
To evaluate the influence of dentin moisture on bond strengths of an etch-and-rinse bonding agent to primary dentin clinically and in the laboratory.


METHODS
The sample consisted of two groups of 20 caries-free primary second molars: molars in exfoliation period (clinical group) and extracted molars (laboratory group). Class I cavities were prepared in all specimens leaving a flat dentin surface on the pulpal floor. A two-step etch-and-rinse adhesive was vigorously rubbed on either dry (n = 5) or wet demineralized dentin (n = 5) under clinical or laboratory conditions. After restorative procedures, the teeth from the clinical group were extracted after 20 minutes. All samples were processed and underwent microtensile bond strength test and silver nitrate uptake evaluation under scanning electron microscopy.


RESULTS
Statistically higher bond strength values were observed when the bonding was performed under laboratory conditions and on a wet demineralized dentin. Most of the failures were adhesive and mixed irrespective of the experimental condition. Silver nitrate uptake occurred in all groups irrespective of the experimental condition. Resin-dentin bond strengths produced in the laboratory in primary teeth may overestimate those produced under clinical circumstances.
School of Dentistry, University Estadual de Ponta Grossa, Paraná, Brazil.
Ana Cláudia
AC
Chibinski
Rodrigo
R
Stanislawczuk
Douglas Augusto
DA
Roderjan
Alessandro Dourado
AD
Loguercio
Denise Stadler
DS
Wambier
Rosa Helena Miranda
RH
Grande
Alessandra
A
Reis
D000134:Acid Etching, Dental / Q000379:methods*; D000268:Adhesiveness; D002648:Child; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000145:classification; D003763:Dental Leakage / Q000145:classification; D003764:Dental Materials / Q000737:chemistry; D003793:Dental Restoration, Permanent / Q000145:classification; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D003890:Desiccation; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008963:Molar / Q000648:ultrastructure; D010756:Phosphoric Acids / Q000737:chemistry; D016622:Silver Staining; D013314:Stress, Mechanical; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014094:Tooth, Deciduous / Q000648:ultrastructure*; D014867:Water / Q000737:chemistry
D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D010756:Phosphoric Acids; C532387:XP-Bond; D014867:Water; C030242:phosphoric acid