Int Poster J Dent Oral Med 2010, Vol 12 No 1, Poster 482
Influence of Irrigation Solutions on Bond Strength of Resin Cements
Anja Rother, DDS, Prof. Dr. Hans-Guenter Schaller, PD Dr.Christian Ralf Gernhardt,
Department of Operative Dentistry and Periodontology, Martin-Luther-University Halle-Wittenberg
April 1st-4th, 2009
87th Annual Meeting & Exhibition of the IADR
Miami, Florida, USA
The retention of fiber posts in roots is dependent upon the adhesion between the resin cement and the dentin, as well as on the adhesion between the resin cement and posts. However, the adhesion between resin and dentin is considered to be a weak point in luting a fiber post (1, 2). It is known that dentin walls are covered by a heavy smear layer containing debris and remnants of gutta-percha and sealer after post preparation. Furthermore, etching, chemical irrigation, and ultrasonic treatment have been reported to be effective in the removal of the smear layer on endodontically treated dentin. Chemical irrigants, such as solutions of sodium hypochlorite (NaOCl), or EDTA in combination with NaOCl, have been used in previous studies to clean the post space (3, 4). The effect of chemical irrigation on the retention of fiber posts remains uncertain.
The aim of this study was to evaluate microtensile bond strength of a self-etching resin cement (Bifix SE, Voco, Germany) after irrigation with different endodontic irrigants (0.2% chlorhexidine, 1% sodium hypochloride, 19% EDTA) on root dentin in vitro (Figure 1, 2).
|Fig. 1: Special disgned apparatus to test microtensile bond strength
|Fig. 2: Experimental device mounted in an universal testing maschine
Material and Methods
75 single rooted extracted teeth, stored in saline for a maximum of fourteen days after extraction were included. All teeth were specially prepared allowing the evaluation on root canal dentin (Figure 3). The specimens were randomly assigned to five experimental groups of fifteen samples each:
Group 1: Control, Bifix SE/ no irrigation solution; group 2: Bifix SE/ chlorhexidine (CHX); group 3: Bifix SE/ sodium hypochloride (NaOCl); group 4: Bifix SE/ chlorhexidine and sodium hypochloride; group 5: Bifix SE/ EDTA. The different solutions were applied five times for 2 minutes each (Figure 4).
Microtensile bond strength was measured 15 minutes after application using an universal testing machine (Z005, Zwick) (Figure 1, 2). All materials were applied as recommended by the manufacturer and light-cured for 60 seconds. Statistical analysis was performed using SPSS 15.0. The data of mTBS were analysed by one-way anova a. Post hoc pair-wise comparisons were performed using Tukey multiple comparisons and Bonferroni Holm correction. For each outcome, statistical significance was set at p<0.05.
|Fig. 3: Example of a root dentin specimen used in this study to test mTBS
||Fig. 4: Irrigation solutions used in this study (NaOCL, EDTA, Chlorhexidine (CHX)). The solutions were applied five times for 2 minutes each
|Fig. 6: Graphically expression of the results
For the five test series following microtensile bond strengths were evaluated. Mean value and standard deviation in Mpa were shown in table 1 and graphically expressed in figure 5.
Bifix SE showed the highest bond strengths after the use of EDTA as irrigation solution (p<0.05, Bonferroni-Holm). Focusing on the different solutions, significant lower bond strengths values compared to the control were observed in group 2, 3 and 4 (p<0.05, Bonferroni-Holm).
|Tab. 1: Mean value and standard deviation (in Mpa) within the different experimental groups
Within the limitations of an in vitro investigation it can be concluded that all irrigation solutions used in this study influenced bond strength of the self-etching resin cement. Only the use of EDTA improved microtensile bond strength significantly.
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MPa = megapascals
This Poster was submitted by PD Dr. Christian R. Gernhardt.
PD Dr. Christian R. Gernhardt
University School of Dental Medicine, Department of Operative Dentistry and Periodontology
Grosse Steinstrase 19