Journal of Dental Medicine

Normal 0 false false false EN-US X-NONE AR-SA In this practical study, various types of orthodontic separators were analyzed in order to indentify microbial population on them. Due to high amount of time and energy needed on this issue, only 12 patients were selected. The results showed that elastic separators and Brass wire separators involved the highest amount of aerobic and non aerobic bacteria respectively. Moreover, this can be related to the shape, material and speed of separators  in separating teeth and also their place of installation.  This phenomenon is evident in clinical observations that installation place of elastic separators often involves inflammation, pain and acute swelling of gingiva. Also, Brass wire separators cause lower bacterial accumulation and no clinical manifestation of inflammation and swelling.  Besides, it should be considered that it has polished surface and slow separating effect.  According to the results, we should declare that each separator cannot cause accumulation of a specific  type of  microbes. But the only difference between various types of separators is the difference in

Normal 0 false false false EN-US X-NONE AR-SA Periodontal ligament changes depend on amount, duration and type of forces. Teeth movement toward periodontal ligament starts from the initial hours by formation of pressure and traction areas. These areas as well as vascular system must be preserved under the forces. Bone loss is resulted from osteoclasts activity. In spongy bone spaces, osteoid is formed. Due to heavy forces, periodontal tissues are pressed, vessels are blocked and periodontal ligament becomes acellular and hyalinised. Also,The osteocytes of undermining bone are damaged in localized areas. In traction areas, fibroblasts proliferation and elongation of periodontal tissues are resulted and osteoid is formed on the areas which are replaced by bundle bone (a part of lamina dura that includes calcified collagen ligaments). Due to heavy forces, collagen in traction area and blood vessels may become ruptured.

Normal 0 false false false EN-US X-NONE AR-SA Canine retraction was done for 19 patients. Movement , Tipping and rotation of canine and molar movements  was done by two approaches of sliding hook and sliding mechanics using 16% wire and 18% twin edgewise brackets and were compared. 350 g force via elastic chin was applied and measurements were done both intra- and extraorally. There was not any significant statistical difference between canine and molar movements in both approaches. Canine Tipping and rotation in two approaches showed significant difference. In fact, both were lower in sliding hook approach than sliding mechanics. As lower tipping results were obtained in sliding hook approach, it is suggested to apply this method to bodily retract canine.

  Monozygotic twins are genetically identical individuals who can also be mirror image twins and the Differences between them result from environmental factors. current study, monozygotic twins were analyzed in different dentitions of primary, mixed and permanent. As a conclusion, although genetic factors are naturally potent, environmental factors’ role can be increased and weaken the genetic factors.

The purpose of this research was to evaluate the effect of palatal expansion in the treatment of nocturnal enuresis. Enuresis still remains a problem experienced by children and the reason is unclear.Finding a final solution is being sought by the medical profession.Nocturnal enuresis may lead to numerous physical and emotional problems. Currently available treatment options showed satisfactory results in some cases.A treatment sample of 6 boys and 4 girls who ranged in age from 6 to 9 years were selected.Research showed that with palatal expansion (4-7 mm), patients could breath through their nose rathe their mouth as a result, enuresis is reduced significantly.