ABSTRACT: 2851

Effect of Ethanol Application on Post Luting to Intraradicular Dentin

C.A.R. CARVALHO¹, A. CANTORO², A. MAZZONI³, C. GORACCI², L. BRESCHI⁴, and M. FERRARI², ¹USP - Bauru School of Dentistry and University of Siena, Conselheiro Lafaiete, Brazil, ²University of Siena, Italy, ³University of Bologna, Italy, ⁴University of Trieste and IGM-CNR, Unit of Bologna c/o IOR, Bologna, Italy

Objectives: To examine the effect of the application of an ethanol rinse before luting fiber posts to intra-radicular dentine with etch-and-rinse adhesive systems by means of push-out bond strength evaluation and SEM analysis. Methods: Fiber posts were luted to single-canal premolars using Dual Link (DL) in combination with a three-step (All Bond 2) or a two step (One Step Plus) etch-and-rinse adhesive system that were applied as per manufacturers' instructions (control), or with additional rinse of ethanol on acid-etched dentine prior to bonding procedures (experimental). Bonded specimens were sectioned into 1 mm thick slabs and submitted to push-out bond strength testing. In addition specimens from each group were processed for SEM analysis. The normally distributed data with no homogeneous group variances were analyzed with Kruskal-Wallis followed by Dunn's (p<0.05). Failure modes were recorded and analyzed under SEM. Results: Push-out bond strength of All Bond 2 was significantly increased if the adhesive was applied on ethanol-saturated dentine (p<.05), while no significant difference (p>.05) was detected among experimental and control groups for One Step Plus. Irrespective from the adhesive, the SEM analysis revealed a good impregnation patterns when both bonding techniques were employed Conclusions: The use of the additional ethanol rinse on acid-etched dentine revealed higher bond strength of All Bond 2 if compared to control application procedure when used in combination with resin based cement to lute fiber posts to the dowel space. However no bond strength improvements were detected using One Step Plus.

Table 2. Mean push-out bond strength values* (SD) expressed in MPa, number of specimens (N), and percentage of failure mode.

Groups

Bond Strength (SD)

Number of Slices

Failure mode (%)
A/M/PA/C

1. Dual Link + All Bond 2

3.91 (2.0)^b

30

30/48/8/13

2. Dual Link + EtOH + All Bond 2

5.86 (3.07)^a,b

33

20/45/15/20

3. Dual Link + One Step Plus

6.25 (4.37)^a,b

30

29/53/14/4

4. Dual Link + EtOH + One Step Plus

6.25 (2.93)^a

35

15/55/14/15

*Values identified by same superscript letter are not significantly different (p > 0.05) by the Dunn's test.

Failure mode: A= between dentin and cementing agent; M=mixed; PA= between post and cementing agent; C=cohesive in cementing agent

Seq #256 - Polymerization
9:00 AM-10:30 AM, Saturday, July 5, 2008
Metro Toronto Convention Centre Room 801B

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