Effect of resin coating and chlorhexidine on the microleakage of two resin cements after storage.
OBJECTIVE
This study evaluated the effect of resin coating and chlorhexidine (CH) on microleakage of two resin cements (Panavia F2.0, Nexus 2) after water storage.


METHODS
Class V cavities were prepared on the facial and lingual surfaces of 120 intact human molars with gingival margins placed 1 mm below the cementoenamel junction. Indirect composite inlays were fabricated. The specimens were randomly assigned into six groups (n = 40). Indirect composite inlays (Gradia) were cemented as follows: Group 1 (control): inlays were cemented with Panavia F2.0 according to the manufacturer's instructions. Group 2: the ED-primed (ED Primer, Kuraray Dental, Tokyo, Japan) dentin was coated with a resin layer before cementation of the inlays with Panavia F2.0. Group 3: a 2% CH solution was applied before bonding with Panavia F2.0. Group 4: after CH application, the primed dentin was coated with a resin layer before cementation with Panavia F2.0. Group 5: (control) after applying Optibond Solo Plus, the inlays were cemented with Nexus 2. Group 6: after etching, CH was applied, and cementation was performed similarly to group 5. Half the specimens in each group were stored in distilled water for 24 hours, while the other half were stored in distilled water for 6 months. After storage, the teeth were placed in 1% methylene blue dye for 24 hours, sectioned, and evaluated under a 20× stereomicroscope. Dye penetration was scored using 0 to 3 criteria. Data were analyzed using nonparametric tests.


RESULTS
Resin coating of ED primer for Panavia F2.0 significantly reduced microleakage at the gingival margins after 6 months (p < 0.05). CH application in Panavia F2.0 did not lead to a significant difference in the microleakage at both margins, after 24 hours and 6 months (p > 0.05). The application of CH showed significantly less microleakage than that of the control group at the gingival margins of Nexus 2 after 6 months. In general, gingival margins showed more microleakage than occlusal margins.


CONCLUSIONS
An additional resin layer applied to a self-etch cement can improve long-term dentinal sealing for indirect restorations, while CH cannot; however, CH reduces gingival microleakage in an etch-and-rinse cement after aging.
Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Fereshteh
F
Shafiei
Maryam
M
Doozandeh
Ali Asghar
AA
Alavi
D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D002484:Cementation; D002710:Chlorhexidine / Q000627:therapeutic use*; D003188:Composite Resins; D003736:Dental Cavity Lining; D003763:Dental Leakage / Q000517:prevention & control*; D004356:Drug Storage; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007284:Inlays; D008689:Methacrylates; D008963:Molar; D019279:Resin Cements; D055116:Self-Curing of Dental Resins; D018709:Statistics, Nonparametric
D000891:Anti-Infective Agents, Local; D003188:Composite Resins; C500742:ED Primer II; D008689:Methacrylates; C433206:Nexus; C438843:Panavia-Fluoro; D019279:Resin Cements; D002710:Chlorhexidine