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العنوان
Effect of two temporary
cements on the retention of
two implant supported all
ceramic crowns /
المؤلف
Farahat,Mohamed Tarek Abd-al-Mageed.
هيئة الاعداد
باحث / Mohamed Tarek Abd-al-Mageed Farahat
مشرف / Amina Mohamed Hamdy
مشرف / Ahmad Khaled Abo El-Fadl
تاريخ النشر
2018
عدد الصفحات
84p.:
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
طب الأسنان
تاريخ الإجازة
1/1/2018
مكان الإجازة
جامعة عين شمس - كلية طب الأسنان - التركيبات الثابتة
الفهرس
Only 14 pages are availabe for public view

from 84

from 84

Abstract

A suitable compromise between retention and retrievability should
be considered in implant supported restorations. Therfore, cement choosing
should be based on the need for the retrievability and amount of required
retention.
The purpose of this in vitro study was to evaluate the effect of two
temporary cements (Resin based cement and Eugenol free Zinc oxide
cement) on the retention of two titanium implant supported crowns made of
(Polymer infiltrated hybrid glass ceramic and Yttrium stabilized tetragonal
zirconia).
In this in-vitro study, 20 samples including 10 zirconia crowns and
10 VITA ENAMIC crowns were fabricated by CAD/CAM system
cemented on titanium implant abutments. Two temporary cement types
were used, resin based temporary cement and zinc oxide non eugenol
temporary cement.
In this study twenty all ceramic crowns were used, they were
divided according to crown materials into: group I (n=10): Polymer
infiltrated hybrid glass ceramic (VITA ENAMIC™) crowns group II
(n=10): Yttrium stabilized tetragonal zirconia (BruxZir™ Shaded Zirconia)
crowns.
Each group was subdivided according to the cement type used into:
Subgroup A (n=5): crowns were cemented on abutments using resin based
temporary cement (Dentotemp™) and Subgroup B (n=5): crowns were
cemented on abutments using non eugenol zinc oxide temporary cement
(Tempbond NE™). Retention of the restoration in these groups was then
measured. Dummy implants were inserted in acrylic resin using paralleling
device, titanium abutments were screwed on the dummy implants using
1.25mm diameter Hex and tightened with a precise adjustable torque
wrench to a 35Ncm.
Titanium abutments were sprayed with a reflective spray and
digitally scanned using desktop scanner, Crowns were designed as
premolars and adjusted on the designing software to fit on the abutments,
then mesial and distal wings were added to aid in the test.
The design was saved as STL file and sent to the milling machine
software were the material was selected and the milling started. VITA
ENAMIC™ crowns were separated from the blocks after milling was
finished, fitting was checked on the abutments to give its final shape.
BruxZir™ Shaded zirconia crowns were separated from the blanks
then placed under drying lamp for 45 minutes, then sintered for 6 hours in
the sintering furnace at 1550°C. The crowns were left in the furnace for
cooling to a temperature below 200◦C, giving its final shape, then fitness
on the titanium abutments was checked.
Cements were mixed using the manufacturer instructions and
applied on the fitting surfaces of the crowns in each group, Crowns were
pressed on the abutments by a loading device under 5 kg weight, after
setting time the samples were ready for testing.
Retention was measured by Nexygen™ Materials Testing Machine
(Model LRX-Plus, Lloyd Instruments, Fareham, UK), Data were recorded
using computer software (Nexygen-MT-4.6; Lloyd Instruments). Numerical data were explored for normality by checking the data
distribution, calculating the mean and median values and using
Kolmogorov-Smirnov and Shapiro-Wilk tests. Data showed parametric
distribution so; it was represented by mean and standard deviation (SD)
values. Two-way ANOVA was used to study the effect of different tested
variables and their interaction on retention. Independent t-test was used for
different intergroup comparisons. The significance level was set at P <
0.05. Statistical analysis was performed with IBM™ SPSS™ Statistics
Version 24 for Windows.