الفهرس 
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Abstract
The present study was done to study the surface analysis and bond
strength after different methods of surface treatment of titanium bonded to
dentin with resin based cement. The tested materials were one titanium alloy
and one resin cement. 120 circular form discs of titanium alloy (Ti -6Al -4V )
were made with 4mm in diameter , 4mm thickness and 12.5 mm2 surface
area.
The prepared discs were divided into 5 groups according to the method
of the surface treatment applied: Sandblasting group with two subgroups
(TS1 and TS2) according to the particle size of Al2O3 powder was used (50
and 250 )μm grit-size , Hydrochloric acid group with two subgroups (TH1,
TH2) according to concentration of HCl acid was used (0.1N, 1
N),Hydrogen peroxide group with two subgroups (TO1, TO2) according
totime of immersion and, Plasma focus group( TP) in addition to the control
group(TC).
After surface treatment was finished the submerged samples were then
placed in a solicitor for 10 minutes, rinsed and then soaked in distilled water
for 2 minutes, and then dried in air at room temperature, and became ready
for cementation.
The surfaces topography after treatment were characterized by surface
roughness,that was carried out using Atomic force microscope (AFM), X-ray
diffractometry (XRD), Scanning Electron Microscope with the Energy
Dispersive X-ray (EDXA) attachment was used to investigate surface
morphology and the elemental composition of titanium alloy disc before and
after surface treatment .The weight loss was derived from the weight
differences before and after treatment.
disc form samples of the titanium alloy was cemented to human
dentin with luting resin adhesive cement by a specially constructed guided
cementation device for the proper orientation of the samples and perfect
position together under static load and were tested for shear bond strength
with the universal testing machine, the obtained results were calculated,
tabulated and statistically analyzed. Photographic records of the debonded
surfaces was examined using stereo microscope with 25x magnification for
determination of the type of bond failure and Scanning Electron Microscope
was used to investigate surface morphology after debonding .
After debonding, the Fourier transform infrared (FTIR) spectrometer
was used to analyze the composition of the debonded surfaces; a potassium
Bromide (KBr) pellet transmission was used.
The recorded data were evaluated and following conclusions were
formulated.
1- Initially, the surface treated titanium alloy demonstrated significantly
high roughness than the nontreated titanium alloys.
2- The quality and grain size of the sandblasting used for surface treatment
influences the size of the defects and the roughness of the titanium surface.
3- The surface composition was altered probably because of reactions
with the used material.
4- The performance of luting media is governed by their bond
strength to the type of the surface treatment was used.
5-from this study (mechanical testing and analytical study, EDAX) it
was recognized that the change in alloying elements content and %
have different influences on the bond strength of titanium and resin
cement.
6-All debonded specimens showed mixed adhesive and cohesive types of
failure: the adhesive failure occurred at cement/titanium interface and
the cohesive failure occurred within the cement material itself.
7-In addition to the effect of the variation in surface chemistry of titanium
discs, in response to surface treatment applied, on their bond strength to
the luting cements, the effect of the variation in surface
microtopography should also be considered.