Background: Evaluation and measurement of primary stability could be achieved by several methods, including the resonance frequency analysis (RFA) and implant insertion torque (IT) values. The need for a sufficient primary stability, guaranteed by an adequate insertion torque and implant stability quotient values, increased its importance mainly in one stage implants or in immediate loading protocols. The aims of this study was to find if there is a correlation between the peak insertion torque (PIT) and ISQ values of implants inserted in the jaws of different bone quality which regarded as two important clinical determinant factors for prediction of implant primary stability, and to evaluate and compare whether an experienced clinician could precisely predict the primary stability of an implant on insertion with different surgical procedures using his own tactile perception. Materials and methods: A total of (60) Iraqi adult patients, (28) males and (32) females, age ranged (22-66) years old were enrolled in this clinical prospective study. The maximum torque value recorded on implant insertion using calibrated manual torque ratchet adopting three categories: low (10 to 30 N/cm), medium (30 to 50 N/cm), and high insertion torque (50 to 70 N/cm). The oral surgeon was asked to indicate the perceived ISQs values according to his perception then Implant stability quotient were measured by Osstell ™. Bone density (type) was determined according to subjective bone resistance encountered while drilling as proposed by Lekohlm and Zarb. Results: A total of 160 implants were inserted. The mean peak IT value was 49 ± 2.61N/cm. The mean ISQ value was 71.7 ± 8.86. Statistical analysis show a significant correlation between ISQ values and PIT values (P<0.001) , between IT values and bone types and between perceived primary stability and actual primary stability (P<0.001) . Conclusions:The corresponding significant correlations between insertion torque, and ISQ values may help clinicians to predict primary stability on implant insertion, that may be associated with implant survival and success rates. A moderate reliability (correlation) between perceived ISQ values and those measured using RF analyzer(Ossttel device).
Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u
... Show MoreThe effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had
... Show MoreThe reaction oisolated and characterized by elemental analysis (C,H,N) , 1H-NMR, mass spectra and Fourier transform (Ft-IR). The reaction of the (L-AZD) with: [VO(II), Cr(III), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II)], has been investigated and was isolated as tri nuclear cluster and characterized by: Ft-IR, U. v- Visible, electrical conductivity, magnetic susceptibilities at 25 Co, atomic absorption and molar ratio. Spectroscopic evidence showed that the binding of metal ions were through azide and carbonyl moieties resulting in a six- coordinating metal ions in [Cr (III), Mn (II), Co (II) and Ni (II)]. The Vo (II), Cu (II), Zn (II), Cd (II) and Hg (II) were coordinated through azide group only forming square pyramidal
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