البيانات الاساسيه

السيره الذاتيه

AMR GIBALY

عنوان رسالة الماجستير

REGENERATION OF BONE AFTER PLACMENT OF ?CO-POLYMER OF L-D POLYLACTIC AND POLY GLYCOLIC ACIDS IN SURGICALLY CREATED DEFECTS

ملخص رسالة الماجستير

This experimental study was conducted on twelve mongrels dogs, standard critical size defects were surgically created in both sides of the mandible of all of the animals. The right side defects were obliterated by a mixture of gel type and powder type Fisiograft which is a copolymer of Polylactic and Polyglycolic acids. While the left side defects were left empty to act as controls. At each interval of one, three, six and nine months postoperative , the dogs were sacrificed and the test and control defects were compared histologically. 1) The histological examination after one month revealed that in both the test and control defects, masses of granulation tissue invaded the created defects, few osteoid tissue appeared only in the base of the defect in the control defects. On the other hand, much more osteoid tissue appeared along the periphery of the test side defect and few of them were scattered in the center of the defect. 2) After three months, the new formed bone creped along the periphery of the test side defect, became homogenous and showed continuity with the normal bone , while in the control defect, it was still accentuated in the base of the defect , separated by fibrous tissue from normal bone and composed of heterogeneous masses. 3) The specimens of the sixth month showed condensation of the haversian systems of both defects, but those of the test side were more homogenous and mature. 4) After nine months, there was marked maturation of the new bone formed in the control side, while the rate of maturation of the test side was markedly slowed down, wide bone marrow spaces and poor haversian systems were demonstrated in both defects, however, the bone quality of the test side defects was ahead of that of the control side defects, as narrower bone marrow spaces and more mature haversian systems were demonstrated in the test side defects.

عنوان رسالة الدكتوراه

RADIOGRAPHIC EVALUATION OF THE EFFECT OF LOW INTESITY LASER IRRADIATION ON IMMEDIATLY LOADED DENTAL IMPLANTS AFTER BONE REAMING AND TAPPING

ملخص رسالة الدكتوراه

Summary: The current study was conducted in an attempt to evaluate the effect of the low intensity laser irradiation on the bone quality formed around immediately loaded titanium implants that were inserted after bone reaming and tapping. Sixteen implants were placed in the maxillae of sixteen male patients, whose ages ranged from (31 to 42 years), all the implants were immediately loaded utilizing properly adjusted resilient interim prosthesis. The patients were then randomly divided into two groups, non-laser (conventional) group , in which the implants were left to heal without any intervention, and the laser group, in which the patients of this group were subjected to Gallium arsenide diode laser of (904 nm) wavelength, (2 Watt) output and (3000 Hz) frequency. The patients administrated four sessions on four alternative days beginning from the eighth day postoperative, each session lasted for five minutes. A follow-up period of six months was applied to the patients of both groups. All the patients were subjected to digital orthopanographs (panoramic radiographs) immediately postoperative, which represented the base line radiographs, 45 days postoperatively (1 month post last laser session) and six months postoperatively (just after the final prosthesis had delivered). The radiographic assessment was carried out through these periods using IDRISI Kilimanjaro software in order to monitor the changes within the bone density along the zones of bone-implant interface (Zone I) and the implant surrounding bone (Zone II). The results revealed that there was a statistically significant cumulative effect in bone density of both zones per time among the lased and non-lased groups which was attributed to the controlled immediate loading. In both groups, lased and non-lased, the rates of progress of bone density through the different intervals increased. However, the application of the Gallium arsenide diode laser revealed a statistically significant value in the percentage increase of the mean bone density in both studied bony zones, along the bone-implant interface (Zone I) as well as within the bone surrounding the implant (Zone II). The low intensity laser irradiation significantly promoted bone healing surrounding titanium implants. The bone healing process together with the osseointegration progressed rapidly in the lased group more than the non-lased group. Although the bone density along the zone of osseointegration was higher than that of the surrounding bone regardless lased or not, a statistically significant difference with regard to the rate of bone density increase between Zone I and Zone II was detected favoring the laser effect on the zone of osseointegration. Conclusions: According to the elaborated results, it can be concluded that: The low intensity laser irradiation provided a safe and easy method for accelerating bone healing surrounding titanium implants. Bone healing and osseointegration progressed uniformly and more rapidly in the lased group versus the non-lased group. The low intensity laser significantly improved the quality of the bone formed either along the bone-implant interface or within the bone surrounding the implant, however, the effect was more profound along the osseointegration zone due to the fact that laser exhibits an enhanced effect at sites that show inflammation, regeneration and high cellular activity. Regardless lased or not, the bone density surrounding immediately loaded dental implants of properly adjusted resilient interim prosthesis improved significantly.