Aims: This study investigates the condyle position in temporal fossa of completely and partially dentated patients pre and post prosthetic treatment, and compares between right and left condyles in both groups by radiographic Examination. Materials and Methods: Twenty two completely dentate patients (20-28) years old, and thirty partially dentate patients (35-65) years old meet the criteria of the study. For each patient a temporary removable acrylic partial denture was constructed. By using planmeca digital radiography device (Finland), the radiograph for TMJ were taken by special panoramic technique in open and close mouth position for both groups (Pre, at, and Post insertion of dental prosthesis). By using Dimaxis software program the linear measurements of the narrowest anterior and posterior joint spaces made by using program tools, the articular eminence inclination angle in closed mouth position also measured, and statistical analysis by using SPSS program version 11.5 for all data. Results: The results showed that in completely dentated patient, 76.5% had condyles in concentric position, patients who had lost posterior teeth support showed a predominance of posterior condylar positions and significant decreased in displacement after prosthodontic treatment (P=0.015 for right side and P=0.032 for left side) at significant level 0.05. Asymmetry in concentric position of condyle between right and left side, but insignificant value P>0.05. There is significant difference in the inclination of articular eminence angle between completely and partially dentate patients P=0.01 for the right side and P=.005for the left side. Conclusions: Posterior displacement of the condyle associated with loss of posterior teeth. Significant change in the condylar position occurred after prosthetic rehabilitation, patient's comfort obtained when the position of condyle in glenoid fossa is (concentric position + 0.35mm). The loss of teeth caused remodeling of articular eminence inclination.

Aims: The aim of this study is to evaluate the biological activities of three soldering materials used for joining Co-Cr joints (iron, stainless steel, and brass) on the tissue of the Rabbit. Materials and Methods: Nine specimens of each iron, stainless steel, and brass where made as cylinders (3mm x 2.5mm). The middle part was made of the brazing materials and the upper and lower parts were made of Co-Cr. These specimens where implanted in the subcutaneous tissue of the rabbit, after two weeks the animals where sacrificed and biopsies where made and examined under microscope by three oral pathologists. Results: Stainless steel implants were the most biocompatible material among the three materials used as brazing materials. Stainless steel sites had insignificant differences with the control sites. Significant difference was found between the iron implanted sites and the control group. This result found by two viewers (A, and M), while the third viewer (Z) found no significant difference between the control group, and the iron implanted sites. Significant difference was found between the brass implanted sites and the control group, this result was found by the three viewers (A, M, and Z). Conclusions: The stainless steel had the most favorable tissue response among the three soldering materials, iron is in the second rank, and brass showed unfavorable tissue response due to release of Cu.

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Aims: To satisfy the newly reverse modified intra-oral periapical projection, in order to reduce the patient discomfort and eliminate gagging reflex during periapical radiography of the lower posterior teeth. Materials and methods: Twenty voluntaries patients have been used in this research aged between 20-25 years, each patient subjected for two intra-oral periapical radiographic examinations for lower posterior teeth (premolars and molars). The first radiographic exam ination has been made with ordinary principles of intra-oral periapical radiographic projection, while the second radiograph has been made with reverse modified principles of intraoral periapical radiographic projection. Five independent examiners (two oral radiographer, oral surgeon, oral diagnosis and oral medicine), rated the two radiographic images obtained from both radiographic examination methods. Image quality was assessed by rating the vis ibility of five anatomical landmarks: tooth structures identification (enamel, dentin and root canal system), bone trabiculation, mental foramen borders, inferior dental canal borders and lamina dura. Results: The data collected from the evaluation of the radiographic images obtained from both radiographic projections were analyzed by paired samples chi-square test, which shown no significant difference (P> 0.05) in image quality obtained from both techniques for five selected structures. The bone trabeculae and the lamina dura given higher rating of total score with ordinary technique (54, 49 points respectively) when compared with reverse r adiographic technique (47, 41 points respectively). The highest percentage of unrecognized shadow of mental foramen and the inferior dental canal with use of ordinary radiographic technique (40%, 30% respectively), while the other examined anatomic structures (tooth structure, bone trabeculae and lamina dura) can be identified clearly with both radiographic techniques. Higher percentage of gag reflex and pain discomfort was observed with ordinary technique projection (45%, 40% respectively) in comparison with reverse technique proje ction (0%, 5% respectively). Conclusion: the reverse intra-oral periapical radiographic technique can be used accurately in the radiographic projection of the mandibular posterior teeth; with minimal pain discomforted and with eliminated gagging reflex initiation.

Aims: the aim of this study is to determine a calibration factor to eliminate the distortion in the linear cephalometric measurements. Materials and Methods; the study was performed on the 5 dry skulls, the first skull contained 12 radiopaque markers fixed at different plains, and radiographed by digital cephalometric x-ray machine. The X and Y axes of the shadow of each radiopaque marker used to estimate the calibration factor. Eight linear distances measured directly and radiographically on the conventional cephalographs of the 5 skulls to evaluate the detected calibration factor. Results; the results showed no-significant difference (p > 0.05) between the direct and calibrated radiographic measurement on the digital and conventional cephalographs. whereas significant difference was found between the conventional cephalometric linear measurements as compared with direct anatomical linear and the conventional cephalometric linear measurements with those measurements manipulated with the estimated calibration factor (p < 0.05). Conclusions; this study found that the conventional cephalometric linear measurements could be reliable as that of digital cephalometric linear measurements, if it's calibrated by the calibration factor (1.08) which is estimated by the present study.