000			03846nam a22002537a 4500
999			_c59437 _d59437
008			181226s2012 ua a|||g bm|| 00| 0 eng d
040			_cSOUL
041			_aeng _hara
082	0	4	_221 _a617.67 _bA E
100	1		_94857 _aAbd-Elaziz, Monaliza Maher.
245	1	0	_aThe Effect of Light Intensities, Curing Modes and Thermocycling on Tooth-Restoration Interface of Two Different Resin Composites / _cMonaliza Maher Abd-Elaziz ; Supervised by Mohamed Riad Farid, Mohsen Hussien Abi-Elhassan, Hebaallah Mohamed Taher.
246	0	3	_aتأثير اختلاف شدة الضوء و أساليب المعالجة الضوئية و الدورات الحرارية على الالتقاء السنى-الترميمي لنوعين من الكمبوزيت الراتنجى
260			_aCairo : _b Cairo University. Faculty of Oral and Dental Medicine. Department of Operative Dentistry. _c2012.
300			_axii, 99 leaves : _bill. ; _c27 cm + _e1 CD.
500			_aThesis (M.Sc.) - Cairo University. Faculty of Oral and Dental Medicine. Department of Operative Dentistry.
504			_aIncludes bibliographical references.
520			_aThis study was performed to assess the effect of types of composite, light intensities, curing modes and thermocycling on toothrestoration interface. Methods: A total of 160 freshly extracted sound human premolars were selected. Teeth were mounted individually in one inch cylindrical acrylic blocks. Specimens were divided into 2 main groups 80 teeth each according to type of resin composite i.e. either using nanofilled resin composite or using microhybrid resin composite. Each group was further subdivided into two subgroup 40 teeth each according to intensity of light i.e. either low intensity or high intensity .Each subgroup was further divided into two division 20 teeth each according to curing mode i.e. either soft- start polymerization or snap shot polymerization .Each division was finally classified into two classes 10 teeth each according to thermocycling i.e. either did not subjected to thermocycling or subjected to thermocycling. Standardized class v cavities were prepared on buccal surfaces of the teeth. Cavities were restored with the different two types of resin composite using different light intensities and different curing modes. Thermocycling was done for a total 500 cycles at 5ºC and 55ºC with one minute dwell time at each temperature. The roots apices were sealed with wax and the teeth were covered with two coats of nail varnish except 1mm around the restoration then immersed in 0.5 % basic methylene blue for 24 hours, after rinsing the specimens were longitudinally sectioned and dye penetration was assessed under a stereomicroscope(X 20). Results: whether occlusal leakage or gingival leakage, there was no significant difference in microleakage of the two types of resin composite when cured with different light intensities of LED (low or high intensity) using different curing modes ( snapshot or soft start curing modes).there was a significant difference in microleakage between the non-thermocycled and thermocycled specimens. Conclusion: 1-The tightness of seal of resin composites is not affected by the variation in light intensity of light emitting diode.2-The curing modes of resin composites have no influential effect on decreasing the marginal leakage of resin composite.3-Thermocycling has an adverse effect on the marginal sealing of resin composite restorations.
546			_aText in English, abstracts in English & Arabic.
650	4	0	_94858 _aDentistry, Operative.
700	1		_94859 _aTaher, Hebatallah Mohamed, _esupervisor
700	1		_94856 _aEl Domiaty, Shahira. _esupervisor
710	2		_aCairo University. _bFaculty Of Oral and Dental Medicine. _bDepartment Of oral Medicine.
942			_2ddc _cTHE _iFOD _6FOD