Assessment of four cephalometric measurements utilized in evaluation of the mandibular position

This study was conducted to assess and correlate four cephalometric measurements utilized in evaluating the mandibular position in the anteroposterior direction. The four measurements used were, the SNB angel, Downs facial angle, Bjork's facial angle, and modification of Koski's ratio. Lateral cephalometric radiographs of forty seven adults [20 males and 27 females] with age ranged from 18-20 years were selected for this purpose. All had accepted normal occlusions, normal skeletal relationship and balanced profiles. Statistical analyses were performed to assess these four measurements. The results revealed no significant difference between the norms of males and females in the four measurements. Downs and Bjork's facial angles presented more sysmmetrical normal distribution than SNB angle and Kosk's ratio. A low and non significant correlation was found between Downs and Bjork's facial angles. Therefore, their conjunctive use would be recommended. Finally, a high and significant correlation was found between Bjork's facial angle and SNB angle. Accordingly these two measurements could be interchangeable

Evaluation of anchorage using nance and modified holding arches

The present study was conducted to evaluate the effects of modified Nance holding arch [tranpalatal arch soldered to Nance holding arch] as anchorage unit during canine retraction. Fourteen patients with Class I crowding sheared in this study. They were divided into two equal groups. All patients had orthodontic fixed appliance. In the first group, Nance holding arch was used for anchorage. On the other hand, a modified form of Nance holding arch [transpalatal arch soldered to Nance holding arch] was utilized for anchorage in the second group. Maxillary canines were retracted by power chain. For all patients cephalometric x-ray films and study casts were taken before and after canine's retraction. The results of this study revealed that; the modified Nance holding arch [transpalatal arch soldered to Nance holding arch] proved a very effective anchorage device. On the other hand, there was significant anchorage loss in the first group [Nance group] as there was mesial movement of the maxillary first permanent molars during canine's retraction. In addition there was no significant molar rotation in either group. Finally, the followings were concluded; the modified Nance holding arch provided an effective anchorage device than the Nance holding arch during canines retraction. Also, both Nance holding arch and the modified Nance form proved a very effective anchorage control against molar rotations during canines retraction

Influence of food processing method on the content of nitrates and nitrites in some vegetables available in Cairo Governorate markets

Seventy samples of chosen vegetables available in Cairo governorate markets [Egypt] were investigated for nitrate and nitrite contents. Those samples were purchased during summer 2005. Griess method with reduction of nitrates to nitrites by cadmium column was utilized for the determination of the studied compounds. The nitrate and nitrite contents were determined in freshly and cooked [boiling and frying] vegetable sand potatoes. The research proved that, nitrate and nitrite contents in different freshly vegetables ranged from 94.05 to 685.2 mg as NaNO[3]/kg and 0.19 to 1.91 mg as NaNO[2]/kg [p < 0.01], respectively. There was a significant variation between values recorded for the same kind of vegetables. Second part of the current study was devoted to compare between contents of nitrates and nitrites in consumable part of raw and cooked vegetables. The results have shown that, in most cases vegetables cooked by frying contain nitrates and nitrites lower than its counterparts cooked by boiling. It was noted that, there is a highly significant difference [p < 0.01] between the mean nitrate and nitrite contents in fresh vegetables and vegetables which treated by thermal processing. Based on the calculated daily intake of nitrates and nitrites obtained from different kinds of vegetables according to the Food Balance of Egypt [1998] and compare it with permissible acceptable daily intake [ADI] proposed by FAO/WHO [1995], the obtained results revealed that all investigated samples after cooking provide lower than 47% and 5% of [ADI] for nitrates and nitrites, respectively