| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Emami, Nazanin, et al.
(author)
-
The effect of flow-composite on interfacial-chemistry and morphology of dentin/bonding
- 2008
-
Conference paper (other academic/artistic)abstract
- Objectives: to study the interfacial bond of self-etching primer to coronal and root dentin with and without the use of flow composite. Methods: morphology, structural characteristics and interaction at the interfaces were studied with Raman micro-spectroscopy and SEM. Coronal (superficial) dentin and root (deep) dentin were prepared from eight non-carious extracted premolars. Immediately after extraction, teeth were carefully cleaned and stored in chlorhexidine digluconate solution prior to preparation. Smear-layer was generated by wet grinding with 600 grit silicon carbide polishing paper for 10 s. A self etching primer Xeno III (Dentsply) was applied according to manufacturer instruction. Half of the specimens were covered with a thin layer of Tetric flow (Ivoclar Vivadent) prior to curing. A 1mm slice was cut of the mesial and distal surface of the teeth with a low speed diamond saw to uncover the interfacial margins and hybrid layer. A modified Nakabayashi method, using HCl and HNO3 followed by NaOCl, was used to show the penetration depth of the monomers. SEM images from 750 to 6000 magnification were collected from dentin/bonding interfaces. Raman spectrums were collected at 1µm intervals across the dentin/bonding interface and provided chemical information. Degree of demineralization as function of depth was calculated. Results: No difference in degree of demineralization was seen between coronal and root dentin. It was slightly lower by using a thin layer of flow prior to curing. The thickness of the dentin/bonding hybrid layer was less for samples with flow and its morphology of hybrid layer and interfacial structure was significantly different. Conclusion: Flow composite had an undesirable affect on the physical-chemistry structure of dentin bonding with a self etching primer. HL and bonding tags morphology was significantly different by using flow composite. No significant different were observed between root and coronal dentin interfaces.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
- Lindberg, A., et al.
(author)
-
A Fourier transform Raman spectroscopy analysis of the degree of conversion of a universal hybrid resin composite cured with light-emitting diode curing units
- 2005
-
In: Swedish Dental Journal. - 0347-9994. ; 29:3, s. 105-112
-
Journal article (peer-reviewed)abstract
- The degree of conversion (DC), of a universal hybrid resin composite cured with LED curing units with low and high power densities and a 510 mW/cm2 quartz tungsten halogen unit, was investigated with Fourier Transform Raman spectroscopy. Three curing depths (0, 2, 4mm) and 0 and 7 mm light guide tip - resin composite (LT - RC) distances were tested. The DC of the LED units varied between 52.3% - 59.8% at the top surface and 46.4% - 57.0% at 4 mm depth. The DC of specimen cured with a 0 mm LT- RC distance at 4 mm depth varied between 50.8% - 57.0% and with 7 mm distance between 46.4% - 55.4%. The low power density LED unit showed a significantly lower DC for both distances at all depth levels compared to the other curing units (p < 0.05). Significant differences between the other curing units were only found at the 4 mm depth level cured from 7 mm distance (p < 0.05). The reduction in DC by increasing LT- RC distance was less than 10% for all curing units. It can be concluded that the improved LED curing units could cure the studied resin composite to the same DC as the control unit.
|
|
| 13. |
- Melek, William W., et al.
(author)
-
A fuzzy noise-rejection data partitioning algorithm
- 2005
-
In: International Journal of Approximate Reasoning. - : Elsevier BV. - 0888-613X .- 1873-4731. ; 38:1, s. 1-17
-
Journal article (peer-reviewed)abstract
- Fuzzy C-Means (FCM) and hard clustering are the most common tools for data partitioning. However, the presence of noisy observations in the data being partitioned may render these clustering algorithms unreliable. In this paper, we introduce a robust noise-rejection clustering algorithm based on a combination of techniques that treat the FCM pitfalls with an outliers exclusion criterion. Unlike the traditional FCM, the proposed clustering tool provides much efficient data partitioning capabilities in the presence of noise and outliers. At the conclusion of the theoretical development, we validate the effectiveness of the proposed noise-rejection data partitioning tool through various comparison studies with existing noise-rejection clustering approaches in the literature. © 2004 Elsevier Inc. All rights reserved.
|
|
| 14. |
- Najafi-Ghezeljeh, T., et al.
(author)
-
Adaptation and validation of the Iranian version of Angina Pectoris characteristics questionnaire
- 2008
-
In: International Journal of Nursing Practice. - 1440-172X. ; 14:6, s. 470-6
-
Journal article (peer-reviewed)abstract
- Research aimed at evaluating Angina Pectoris (AP) symptoms in patients with Coronary Heart Disease (CHD) requires a comprehensive assessment tool applicable to this population. Because no single existing measure assessed the full range of symptom characteristics important to our study, we combined two measures (the modified Rose Questionnaire (MRQ), and the Short Form-McGill Pain Questionnaire (SF-MPQ) and added one item to examine specific aspects of AP symptoms (Accompanying Symptom Checklist). The purposes of this study are: (i) to describe the process of translating the SF-MPQ, MRQ and accompanying symptom checklist from English to the Farsi language; and (ii) to evaluate substantial psychometric works (content and construct validity) for the entire instrument and each part of it (SF-MPQ, MRQ and accompanying symptom checklist). A cross-cultural adaptation of the instrument was carried out before developing the final version of it. To these ends, one hundred and 10 CHD patients with AP were assessed by this hybrid measure in an initial study. An analysis of the results indicated that a content valid instrument had been developed. There was a significantly high correlation between scores in the SF-MPQ and there were associations between items in the MRQ. The Iranian version of AP characteristics questionnaire is valid; it is capable of describing characteristics of AP symptoms. However, the reliability of the instrument needs to be assessed through further research.
|
|
| 15. |
- Najafi-Ghezeljeh, T., et al.
(author)
-
The Iranian version of Angina Pectoris characteristics questionnaire: reliability assessment
- 2009
-
In: J Clin Nurs. - 1365-2702. ; 18:5, s. 694-9
-
Journal article (peer-reviewed)abstract
- AIMS: To evaluate internal consistency and test-retest reliability of the Iranian version of the Angina Pectoris characteristics questionnaire. BACKGROUND: To evaluate symptoms in patients with Angina Pectoris, the Iranian version of the Angina Pectoris characteristics questionnaire was created by combining items from Modified Rose Questionnaire, Short Form-McGill Questionnaire and the Accompanying Symptom Checklist. The Angina Pectoris characteristics questionnaire has been developed and validated recently although it required assessment of its reliability. DESIGN: Reliability study using test and retest. METHOD: One hundred and ten coronary heart disease patients with Angina Pectoris were included. The test-retest reliability of the instrument was estimated for measurement after 15 days. RESULT: The analysis of the result indicated that internal consistency was found adequate at both assessments (Cronbach's alpha = 0.65) for test and retest. There was no significant difference between test and retest. The intra-class correlation coefficient ranged from 0.76-0.98. CONCLUSION: The Angina Pectoris characteristics questionnaire is a reliable instrument for the assessment of Angina Pectoris characteristics in a Persian population. RELEVANCE TO CLINICAL PRACTICE: The Angina Pectoris characteristics questionnaire can be used with confidence in Iranian coronary heart disease patients for Assessing Angina Pectoris symptom.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
