scholarly journals Effects of a Self-Etching Primer and 37% Phosphoric Acid Etching on Enamel: A Scanning Electron Microscopic Study

2012 ◽  
Vol 13 (3) ◽  
pp. 280-284 ◽  
Author(s):  
Lalita G Nanjannawar ◽  
Girish S Nanjannawar

ABSTRACT Objective The purpose of this study was to compare the etching effects of a self-etching primer with 37% phosphoric acid on enamel by using a scanning electron microscope. Bond strength and the site of bond failure were also determined for brackets bonded using SEP and 37% phosphoric acid. Materials and methods A total of 60 maxillary premolar teeth were used for this study and they were divided into four groups. First two groups were used for studying the different types of etch patterns obtained and the next two groups were used to test the bond strength with the help of Universal testing machine. After debonding, the amount of residual adhesive was assessed according to adhesive remnant index using a stereomicroscope. Results The majority of etch patterns obtained in the 37% phosphoric acid group were type II, whereas in the SEP group, type IV pattern was more common. There was no statistically significant difference between mean bond strengths obtained with the SEP group and the phosphoric acid group. Use of SEP results in less amount of residual adhesive on tooth surface after debonding. Conclusion SEP produces more conservative etch pattern compared to 37% phosphoric acid. Use of SEP for bonding provides similar and clinically acceptable bond strength compared to use of 37% phosphoric acid etching technique and requires less clean-up procedures hence, reduces enamel loss. Clinical significance Use of 37% phosphoric acid for orthodontic bonding yields high bond strength but, causes enamel loss during both etching and debonding. SEPs not only provide adequate bond strength with a more conservative etch pattern but also enable easy debonding, thereby reducing the enamel damage. How to cite this article Nanjannawar LG, Nanjannawar GS. Effects of A Self-Etching Primer and 37% Phosphoric Acid Etching on Enamel: A Scanning Electron Microscopic Study. J Contemp Dent Pract 2012;13(3):280-284.

2015 ◽  
Vol 20 (4) ◽  
pp. 51-56 ◽  
Author(s):  
João Paulo Fragomeni Stella ◽  
Andrea Becker Oliveira ◽  
Lincoln Issamu Nojima ◽  
Mariana Marquezan

OBJECTIVE: To assess four different chemical surface conditioning methods for ceramic material before bracket bonding, and their impact on shear bond strength and surface integrity at debonding.METHODS: Four experimental groups (n = 13) were set up according to the ceramic conditioning method: G1 = 37% phosphoric acid etching followed by silane application; G2 = 37% liquid phosphoric acid etching, no rinsing, followed by silane application; G3 = 10% hydrofluoric acid etching alone; and G4 = 10% hydrofluoric acid etching followed by silane application. After surface conditioning, metal brackets were bonded to porcelain by means of the Transbond XP system (3M Unitek). Samples were submitted to shear bond strength tests in a universal testing machine and the surfaces were later assessed with a microscope under 8 X magnification. ANOVA/Tukey tests were performed to establish the difference between groups (α= 5%).RESULTS: The highest shear bond strength values were found in groups G3 and G4 (22.01 ± 2.15 MPa and 22.83 ± 3.32 Mpa, respectively), followed by G1 (16.42 ± 3.61 MPa) and G2 (9.29 ± 1.95 MPa). As regards surface evaluation after bracket debonding, the use of liquid phosphoric acid followed by silane application (G2) produced the least damage to porcelain. When hydrofluoric acid and silane were applied, the risk of ceramic fracture increased.CONCLUSIONS: Acceptable levels of bond strength for clinical use were reached by all methods tested; however, liquid phosphoric acid etching followed by silane application (G2) resulted in the least damage to the ceramic surface.


Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2902
Author(s):  
Phoebe Burrer ◽  
Hoang Dang ◽  
Matej Par ◽  
Thomas Attin ◽  
Tobias T. Tauböck

This study investigated the effect of over-etching and prolonged application time of a universal adhesive on dentin bond strength. Ninety extracted human molars were ground to dentin and randomly allocated into nine groups (G1–9; n = 10 per group), according to the following acid etching and adhesive application times. In the control group (G1), phosphoric acid etching was performed for 15 s followed by application of the universal adhesive Scotchbond Universal (3M) for 20 s, as per manufacturer’s instructions. In groups G2–5, both the etching and adhesive application times were either halved, doubled, quadrupled, or increased eightfold. In groups G6–9, etching times remained the same as in G2–5 (7.5 s, 30 s, 60 s, and 120 s, respectively), but the adhesive application time was set at 20 s as in the control group (G1). Specimens were then restored with a nanofilled composite material and subjected to microtensile bond strength testing. Bond strength data were statistically analyzed by ANOVA and Tukey’s post-hoc tests (α = 0.05). The relationship of bond strength with etching and adhesive application time was examined using linear regression analysis. Treatment of dentin with halved phosphoric acid etching and adhesive application times (G2) resulted in a significant bond strength decrease compared to the control group (G1) and all other test groups, including the group with halved acid etching, but 20 s of adhesive application time (G6). No significant differences in bond strength were found for groups with multiplied etching times and an adhesive application time of 20 s or more, when compared to the control group (G1). In conclusion, a universal adhesive application time of at least 20 s is recommended when bonding to over-etched dentin.


2015 ◽  
Vol 34 (2) ◽  
pp. 219-226 ◽  
Author(s):  
Hiroshi NOGAWA ◽  
Hiroyasu KOIZUMI ◽  
Osamu SAIKI ◽  
Haruto HIRABA ◽  
Mitsuo NAKAMURA ◽  
...  

1987 ◽  
Vol 14 (2) ◽  
pp. 105-107 ◽  
Author(s):  
R. G. Oliver

The etch pattern produced on enamel from unerupted and erupted human teeth with varying periods of acid etching using 37 per cent phosphoric acid was examined using a scanning electron microscope. For erupted enamel etch scores were fairly consistent above 10 seconds etching, for unerupted enamel etch scores matched those for erupted enamel for etch times above 30 seconds. The etch type was more consistent on unerupted enamel.


1997 ◽  
Vol 11 (3) ◽  
pp. 157-160 ◽  
Author(s):  
Marcelo FAVA ◽  
Ii-Sei WATANABE ◽  
Flávio FAVA DE MORAES ◽  
Luciane RIBEIRO DE REZENDE SUCASAS DA COSTA

Under the scanning electron microscope, the characteristics of the buccal surface enamel of human non-erupted deciduous molars were evaluated after using 15, 30, and 45 seconds of phosphoric acid etching time. The teeth were extracted, kept in a 70% alcohol solution and later dehydrated and metallized for analysis with the scanning electron microscope JEOL, JSM-6.100. The in vitro experiment with 35% phosphoric acid revealed that there is a tendency of predominance of interprismatic enamel dissolution or type II pattern with 15 and 45 seconds etching time. The dissolution of the interprismatic enamel was more pronounced when an acid etching time of 45 seconds was used. The enamel surface demonstrated type I and type II patterns when acid etching time was 30 seconds


2015 ◽  
Vol 31 ◽  
pp. e8
Author(s):  
Y. Tamura ◽  
S. Shibasaki ◽  
S. Matsuyoshi ◽  
K. Tsubota ◽  
T. Takamizawa ◽  
...  

2020 ◽  
Vol 45 (6) ◽  
pp. 643-654
Author(s):  
P Kanzow ◽  
L Piecha ◽  
J Biermann ◽  
A Wiegand

Clinical Relevance Contamination of enamel and dentin with repair surface conditioning measures should be avoided. SUMMARY Objectives: To analyze whether the contamination with different repair conditioning measures impairs the adhesive performance of a universal adhesive applied in etch-and-rinse mode (ER) or self-etch mode (SE). Methods and Materials: Bovine enamel and dentin surfaces (each subgroup n=16) were bonded with a universal adhesive in ER or SE after contamination with different repair conditioning measures (sandblasting, silica coating, hydrofluoric acid etching, self-etching ceramic primer). In half of the groups, sand-blasting, silica coating, and hydrofluoric acid etching was followed by the use of a universal primer. If the universal adhesive was applied in ER, contamination was performed either before or after phosphoric acid etching. If the universal adhesive was applied in SE, bonding was performed after contamination. In the control groups, no contamination was simulated. Shear bond strength (SBS) and failure modes of composite buildups were determined after thermal cycling (10,000 cycles, 5°C-55°C). Statistical analysis was performed using analyses of variance, Weibull statistics, and χ2 tests (p<0.05). Results: In ER, sandblasting and silica coating significantly reduced SBS (control: enamel =25.7±4.2 MPa; dentin = 22.0±5.3 MPa) only when performed after phosphoric acid etching. Contamination with hydrofluoric acid impaired SBS on enamel but not on dentin. The self-etching ceramic primer reduced SBS, but not significantly. The contamination with the universal primer had no significant effect. In SE, all repair conditioning measures except the universal primer reduced SBS (control: enamel = 20.3±5.5 MPa; dentin = 23.0±4.0 MPa). Conclusion: Contamination of enamel and dentin by repair conditioning measures potentially affects bond strength.


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