فهرست مطالب aida rajaei

The use of lithium disilicate (LD) glass-ceramic in dentistry is increasing due to its proper mechanical properties and aesthetic appearance. On the other hand, due to the forces acting on dental restorations, materials with mechanical properties as well as suitable tooth color are very important. Titanium nanoparticles (Ti-NP) as a material with suitable mechanical properties can be a used for the production of dental ceramics with higher strength by combining with the LD. The aim of this study was to determine the compressive strength of LD ceramics reinforced with Ti-NP in comparison with conventional LD. This experimental study was performed on 60 LD ceramic blockss containing the desired nanoparticles, Ti-NP with an average particle size of 50-70 nm with the content of 1 wt%, 2 wt% and 5 wt% were pressed in a stainless-steel mold under force of 200-250 MPa and then sintered in the electric furnace. The highest compressive strength of the standard sample groups compared to the commercial LD brand Emax (449±42.920 MPa) was for samples with 5 wt% Ti-NP (341.67 MPa (p <0.001). The addition of 2 wt% and 5 wt% Ti-NP increased the compressive strength of LD ceramic compared to the control group but decreased significantly compared to the conventional commercial sample. The addition of 5 wt% Ti-NP increased the compressive strength of LD ceramic compared to the control group.

Considering the importance of patient mix for an optimal clinical learning process, the aim of this study was to assess the oral care needs of patients referring to the Pediatric Department of Isfahan Dental School and to compare it with the curriculum in order to assess the efficacy of clinical education.
In this cross-sectional analytical study, all the available files in the archives of Pediatric Department were gathered. The information about oral health needs of children referring to this department were elicited and compared with the math product of the number of students in each semester and their educational requirements in practical courses 1‒3. Data were analyzed with SPSS 18. To assess the patient mix, the mean of oral health needs of children in each semester/year was calculated and paired t-test was used to compare the treatment/ preventive needs of children with the care provided for them (α = 0.05).
In clinical courses 1 and 2 most of the provided care was lower than the proposed requirement. In clinical course 3, except for extraction and restoration with preventive resin restoration (PRP), the other dental treatments did not conform to the educational requirement. In relation to the preventive and restorative care in all the clinical courses, it seems the number of cases requiring such care was sufficient for meeting the educational requirement of students but the provided care was less than the proposed requirement. In each child, almost half or one-third of his/her dental needs had been satisfied, which was significantly far from his/her real needs (α = 0.05, p value In most clinical pediatric courses, the number of patients was not sufficient to meet the proposed requirement of students. Therefore, offering off-campus programs might effectively increase the number of patients and the types of dental problems that students would contact with during their clinical courses.