Background: This study designed to shade light on the important role of CBCT in accurate localization of the impacted maxillary canines. Materials and method: Fifty two unilateral and bilateral impacted maxillary canines from 30 patients (24 females and 6 males) were evaluated by a volumetric 3D images obtained from cone beam CT. All samples attended to the specialist health center of dentistry in Al-Sadder City referred to CBCT by oral surgeons or orthodontists to detect the exact position of impacted upper canine in cases when there was no bulging buccally or palatally which aids to detect the exact position. Results: Mesio-palatal angulations had the highest rate (63.5%) followed by mesio-labial (19.2%), vertical (labial) (9.6%), disto-palatal (5.8%) and disto-labial (1.9%). The relation between impacted canine and the adjacent teeth regarding to the attachment was significant only with lateral incisor. No cases of root resorption of the adjacent teeth were recorded. Bilateral impacted teeth were found in 22 patients which is highly significant (especially in females), while unilateral impaction was found only in 8 patients especially in females. Impacted canine was more prominent in female whether unilateral or bilateral. Conclusions: CBCT imaging of impacted canines can show the following: presence or absence of the canine, angulations of the long axis of the tooth, relative labial and palatal positions and proximity to adjacent teeth. In short, CBCT imaging is clearly advantageous in imaging and management of impacted canines.
In this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
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