Comparative In Vitro Study of the Bond Strength of Composite to Enamel and Dentine Obtained with Laser Irradiation or Acid-etch

1999 ◽  
Vol 14 (3) ◽  
pp. 207-215 ◽  
Author(s):  
V. Armengol ◽  
A. Jean ◽  
P. Weiss ◽  
H. Hamel
2000 ◽  
Vol 118 (3) ◽  
pp. 274-279 ◽  
Author(s):  
Travis Q. Talbot ◽  
Richard J. Blankenau ◽  
Mark E. Zobitz ◽  
Amy L. Weaver ◽  
Christine M. Lohse ◽  
...  

Author(s):  
Sílvia Fontes Do Amaral Pereira

O objetivo do presente estudo in vitro foi verificar, através de teste de cisalhamento, a resistência de união da liga Wironia®light, à base de níquel-cromo sem berílio, sujeita a diferentes tratamentos de superfície, às cerâmicas Vita VM13 e Noritake. Foram confeccionados oitenta espécimes cilíndricos metálicos, com o auxílio de uma matriz de aço, nas dimensões de 4 mm de diâmetro por 4 mm de altura. Os espécimes foram divididos em oito grupos (n=10), de acordo com o tipo de tratamento superficial aplicado à liga metálica e com o tipo de cerâmica testada. Estes foram avaliados de acordo com os critérios de resistência ao cisalhamento e, com o auxílio de microscopia óptica, foi avaliada a área de cerâmica remanescente aderida ao metal após a fratura. Os corpos-de-prova do G6 (fabricados em Cerâmica Noritake com jateamento-26,401 ± 11,637 MPa) apresentaram maior resistência ao cisalhamento (p> 0,05) enquanto que os menores valores foram registrados no G4 (Cerâmica Vita com utilização de broca-13,440 ± 7,766 MPa). G6 (19425,4 μm2) apresentou a maior área de cerâmica aderida ao metal (p> 0,05) enquanto que o G4 (2310,2 μm2) apresentou a menor área. Concluiu-se que G6 obteve os valores mais altos de resistência ao cisalhamento e de remanescente cerâmico aderido à superfície metálica enquanto que o G4 obteve os valores mais baixos. Descritores: Restaurações metalo-cerâmicas; ligas de níquel-cromo;porcelana dentária.


2021 ◽  
Vol 11 (14) ◽  
pp. 6349
Author(s):  
Regina María Del Río Carrillo ◽  
Pedro Molinero-Mourelle ◽  
Vicente Vera ◽  
Pablo Romero Villaba ◽  
Elizabeth Casañas ◽  
...  

To evaluate the bond strength of different universal adhesives on deciduous tooth dentineand their relationship with the composition and potential of hydrogen (pH). Methods: An in vitromicro push-out test on 150 samples (n = 50) per group per adhesive, namely, Adhese Universal(ADH; Ivoclar Vivadent), Futurabond U (FUT; Voco GmbH) (Test), and Scotchbond Universal withpre-conditioning (SCO; 3M) (Control), to record bond strength (BS) and type of adhesive failure.Results: The results of the different adhesives (megapascals (MPa)) varied, showing no statisticalsignificance. The corresponding averages are in MPa: ADH, 13.66 2.81; FUT, 14.48 2.88; SCO,14.98 3.96. Additionally, the frequency of type of failure was as follows: mixed (60.7%), adhesive(27.3%), and cohesive (12%). Conclusions: SCO, with a pH of 2.7, showed greater resistance tofracture, while FUT, with a pH of 2.3 and no pre-conditioning, approached the same values, being aone-step adhesive. No relationship was found between failure and type of adhesive.


Author(s):  
Katharina Kuhn ◽  
Carmen U. Schmid ◽  
Ralph G. Luthardt ◽  
Heike Rudolph ◽  
Rolf Diebolder

AbstractInadvertent Er:YAG laser irradiation occurs in dentistry and may harm restorative materials in teeth. The aim of this in vitro study was to quantify Er:YAG laser-induced damage to a nanohybrid composite in simulated clinical scenarios for inadvertent direct and indirect (reflection) laser irradiation. The simulation was performed by varying the output energy (OE;direct˃indirect) reaching the specimen and the operating distance (OD;direct˂indirect). Composite specimens were irradiated by an Er:YAG laser. The ablation threshold was determined and clinically relevant parameters were applied (n = 6 for each OE/OD combination) for direct (OE: 570 mJ/OD: 10 mm, OE: 190 mJ/OD: 10 mm) and indirect irradiation (OE: 466 mJ/OD: 15 mm, OE: 57 mJ/OD: 15 mm, OE: 155 mJ/OD: 15 mm, OE: 19 mJ/OD: 15 mm). The extent of damage in the form of craters was evaluated using a laser scanning microscope (LSM) and a conventional light microscope (LM). The ablation threshold was determined to be 2.6 J/cm2. The crater diameter showed the highest value (LM: 1075 ± 18 µm/LSM: 1082 ± 17 µm) for indirect irradiation (reflectant:dental mirror) (OE: 466 mJ/OD: 15 mm). The crater depth showed the highest and comparable value for direct (OE: 570 mJ/OD: 10 mm; LSM: 89 ± 2 µm) and indirect irradiation (OE: 466 mJ/OD: 15 mm; LSM: 90 ± 4 µm). For each OD, the crater diameter, depth, and volume increased with higher laser fluence. However, the OD—and thus the laser spot diameter—also had an enlarging effect. Thus, indirect irradiation (reflectant:dental mirror) with only 47% of the laser fluence of direct irradiation led to a larger diameter and a comparable depth. The three-dimensional extent of the crater was large enough to cause roughening, which may lead to plaque accumulation and encourage caries, gingivitis, and periodontitis under clinical conditions. Clinicians should be aware that reflected irradiation can still create such craters.


2012 ◽  
Vol 17 (4) ◽  
pp. 1-7 ◽  
Author(s):  
Roberto Hideo Shimizu ◽  
Karlos Giovani Grando ◽  
Isabela Almeida Shimizu ◽  
Augusto Ricardo Andriguetto ◽  
Ana Cláudia Moreira Melo ◽  
...  

OBJECTIVE: This in vitro study was designed to evaluate the shear bond strength (SBS) of orthodontic metal brackets bonded by direct and indirect techniques. METHODS: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with SondhiTM Rapid-Set system (3M/Unitek), Group II - indirect bonding with TransbondTM XT adhesive system (3M/Unitek) and Group III - direct bonding with TransbondTM XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukey's test for paired means. A 5% significance level was adopted. RESULTS: The results of Group I were 67.6 (N) and 5.9 (MPa); Group II, 68.9 (N) and 6.1 (MPa) and Group III (control), 92.5 (N) and 8.1 (MPa). CONCLUSION: It can therefore be concluded that the means for Group III were significantly higher compared with Groups I and II in both Newton (N) and Megapascal (MPa) values. The means attained by the indirect bonding technique used in Groups I and II, however, exhibited no statistically significant differences.


Sign in / Sign up

Export Citation Format

Share Document