Effect of saliva contamination of shear bond strength of orthodontic brackets when using a self-etch primer

Author(s):  
Mao Jing ◽  
Qi Juan
2008 ◽  
Vol 78 (3) ◽  
pp. 531-536 ◽  
Author(s):  
Mona A. Montasser ◽  
James L. Drummond ◽  
Carla A. Evans

Abstract Objective: To compare rebonding of orthodontic brackets based on the hypothesis that no difference would be found between the adhesive systems with respect to shear bond strength, mode of failure, and clinical failure rates. Materials and Methods: The three adhesive systems included two self-etch primers (Transbond and M-Bond) and a conventional phosphoric acid etch (Rely-a-Bond). The sample size was 20 premolars for each adhesive system. The shear bond strength was tested 24 hours after bracket bonding with the bonding/debonding procedures repeated two times after the first debonding. Bond strength, adhesive remnant index (ARI), and failure sites were evaluated for each debonding. Statistical analysis consisted of a two-way analysis of variance (ANOVA) followed by Scheffè analysis. The clinical portion evaluated 15 patients over a 12-month period. Results: The mean shear bond strengths after the first, second, and third debondings for Rely-a-Bond were 8.4 ± 1.8, 10.3 ± 2.4, and 14.1 ± 3.3 MPa, respectively; for Transbond 11.1 ± 4.6, 13.6 ± 4.5, and 12.9 ± 4.4 MPa, respectively; and for M-Bond 8.7 ± 2.7, 10.4 ± 2.4, and 12.4 ± 3.4 MPa, respectively. After the three debondings the mean shear bond strength increased significantly from the first to the third debonding for Rely-a-Bond and M-bond (P ≤ .001), but did not change for Transbond (P = .199). Conclusions: The original hypothesis is not rejected. The two self-etching primers showing higher or comparable bond strength to the conventional phosphoric etch with less adhesive remnant on the enamel surface after the first debonding. With repeated bonding/debonding, the differences in the bond strength, ARI, and failure site were not significantly different. There was no difference in the clinical performance of the three adhesive systems (P = .667).


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Maria Francesca Sfondrini ◽  
Danilo Fraticelli ◽  
Paola Gandini ◽  
Andrea Scribante

Purpose. The aim of this study was to assess the effect of water and saliva contamination on the shear bond strength and failure site of orthodontic brackets and lingual buttons.Materials and Methods. 120 bovine permanent mandibular incisors were randomly divided into 6 groups of 20 specimens each. Both orthodontic brackets and disinclusion buttons were tested under three different enamel surface conditions: (a) dry, (b) water contamination, and (c) saliva contamination. Brackets and buttons were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values) and Chi squared test (ARI Scores).Results. Noncontaminated enamel surfaces showed the highest bond strengths for both brackets and buttons. Under water and saliva contamination orthodontic brackets groups showed significantly lower shear strengths than disinclusion buttons groups. Significant differences in debond locations were found among the groups under the various enamel surface conditions.Conclusions. Water and saliva contamination of enamel during the bonding procedure lowers bond strength values, more with orthodontic brackets than with disinclusion buttons.


2010 ◽  
Vol 138 (1) ◽  
pp. 79-83 ◽  
Author(s):  
Sergio Ricardo Campos Maia ◽  
Vanessa Cavalli ◽  
Priscila Christiane Suzy Liporoni ◽  
Marcos Augusto do Rego

Author(s):  
Mohammad Moslem Imani ◽  
Farzaneh Aghajani ◽  
Nafiseh Momeni ◽  
Mohammad Sadegh Ahmad Akhoundi

Objectives: In clinical conditions, orthodontic brackets are exposed to periodic stresses mainly induced by mastication and intraoral forces. The objective of the present study was to evaluate the effects of cyclic loading to simulate masticatory forces on shear bond strength (SBS) of metal brackets bonded to teeth using self-etch and total-etch bonding systems. Materials and Methods: Eighty-four caries- and crack-free bovine mandibular incisors were selected and randomly assigned to two groups based on the type of bonding system. After bonding, all samples were thermocycled (500 cycles) followed by cyclic loading of the half of the specimens in each group by applying 40 N load with 2 Hz frequency for 10,000 cycles. The SBS was measured using a universal testing machine. The adhesive remnant index (ARI) score was calculated subsequently. Data were analyzed using Kolmogorov-Smirnov test, two-way ANOVA and Mann-Whitney test. Results: The SBS was 10.09±3.78 MPa and 14.44±6.06 MPa for self-etch and total-etch bonding systems in cyclic loading group, respectively. The SBS was 9.43±5.3 MPa and 11.31±5.42 MPa in self-etch and total-etch groups without cyclic loading, respectively. Cyclic loading did not cause any significant difference in SBS (P>0.05). The ARI scores of the groups were significantly different (P<0.05). Conclusions: The present results demonstrated that low masticatory forces at 10,000 cycles did not have a significant impact on bracket-adhesive SBS; however, they significantly changed the ARI score. Even though the total-etch bonding system yielded higher SBS than the self-etch system, the performance of both was clinically acceptable.


Sign in / Sign up

Export Citation Format

Share Document