Unit:
Κατεύθυνση Προσθετική (Κλινικές Ειδικεύσεις)Βιβλιοθήκη Οδοντιατρικής
Author:
Gonidis Theodoros
Supervisors info:
Γεώργιος Παπαβασιλείου, Επίκουρος Κάθηγητης,Τμήμα Οδοντιατρικής, Σχολή Επιστημών Υγείας, ΕΚΠΑ
Τριαντάφυλλος Παπαδόπουλος, Καθηγητής, Τμήμα Οδοντιατρικής, Σχολή Επιστημών Υγείας, ΕΚΠΑ
Σπύρος Ζηνέλης, Αναπληρωτής Καθηγητής, Τμήμα Οδοντιατρικής, Σχολή Επιστημών Υγείας, ΕΚΠΑ
Original Title:
Αξιολόγηση της συμπεριφοράς του δεσμού συγκόλλησης για δύο τροποποιητικά υλικά επιφάνειας υαλοκεραμικών μετά από δοκιμασία γήρανσης
Translated title:
Evaluation of adhesive bond strength for two different glass - ceramic surface modification systems after ageing test
Summary:
Aim: Comparing the strength of the bond between the surface of lithium disilicate and resinous cement, after surface treatment with two different modification systems and accelerated ageing.
Materials and Method: Forty specimens were manufactured by incorporating IPS e.max press cylinders (r= 2,5mm, H=10mm) into customized acrylic resin matrices with dimensions (r= 7.5mm). Twenty specimens (Group A) of IPS e.max Press were etched with HF 4,9% for 20'' (ceramic etching gel, Ivoclar-vivadent) and afterwards Monobond plus (Ivoclar-vivadent) universal primer was applied. Twenty specimens identical to the previous twenty (Group B) were treated with Monobond Etch and Prime (Ivoclar-vivadent) by 20'' scrubbing and 40'' wait. The samples were rinsed under running water for 1' each and let to dry at room temperature in a dry place.
Cylindrical dies were made for all samples, which were filled with Variolink esthetic DC (Ivoclar-vivadent) resinous double-polymerization cement. Light Polymerization took place for 40'' and afterwards the specimens were covered with glycerin for 1’. The specimens were placed in a glass tray which was then filled with distilled water. They were then placed in an oven at a temperature of 80°C for 2 weeks (14 days). After being removed from the oven, 16 of group A and 19 of group B specimens were found suitable for testing. A shear bond strength test was performed on a Tensometer 10, Monsanto, (Capacity 10kN, 1,000 kgf / 2200lbf). TC914. Once the specimen had been stabilized, a head whose speed was set at 1mm/sec exerted a tendency at the intersection of the ceramic with the cement until it was detached. After the test, the detached specimens were observed in the optical microscope.
Results: We observed that the HF + Monobond plus Group A had mean value= 3.53 MPa and standard deviation = 1.87 while the Monobond etch + prime Group B had mean value= 1.47 MPa and a standard deviation=1.97. We see, therefore, that the first group has a higher average than the second one, indicating that for these specimens more detachment force than the second one is needed. After the results were collected, the linearity tests (in terms of normal distribution) were performed to see if the dependent variable was of this distribution. Based on these results, it was decided to proceed to a non-parametric comparison between the price distributions compared to the two CPs using Mann-Whitney U. After observation in the optical microscope, it was found that the failure in most of the Group A specimens was of mixed type and in all of Group B specimens was of adhesive type.
Conclusions: Even though in this laboratory experimental procedure the selected conditions have no correlation with the clinical conditions that the material could be found in, it highlights the differences between the two systems, which in the long run can become important. In the present experiment we see that monobond etch and prime lacks significantly relative to HF + monobond plus in relation to the strength of the bond with the resinous cement, however further research and long term clinical studies are needed in order to evaluate whether these differences, both in the "degree" of the surface roughness, and in the use of silane, are able to provide a reliable bond between cement and ceramics in the long run.
Main subject category:
Health Sciences
Keywords:
Ceramics, Cementation, Lithium desilicate, Zirconia
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MASTER TELIKO 100119.pdf
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