Background: Relapse of previously moved teeth, is major clinical problem in orthodontics with respect to the goals of successful treatment. This study investigated the effect of orthodontic relapse on the proliferation of fibroblast and epithelial rests of Malassez cells in periodontal ligament of rat molars. Materials and Methods: Sixteen ten-week- old male Wister rats were randomly divided into four groups composed of four animals each: Group I received no orthodontic force (control). In both Group II and Group III, uniform standardized expansive springs were used for moving the maxillary first molars buccally for periods of one and three weeks respectively. The spring initially generated an average expansive force of 20 g on each side. In Group IV the springs were left for three weeks, until the maxillary first molars moved buccally, after that the springs were removed and the animals were scarified after three weeks of relapse tooth movement. After the humanly scarification of animals, each maxilla in all groups was dissected into two halves each half including the three maxillary molars and processed for histological examination. The number of both fibroblast and ERM cells in each cluster was counted in the PDL of the pressure side of the mesio-buccal roots of the maxillary right and left first molars in all groups and the surface areas of the ERM clusters were also measured in all groups. Results: The number of fibroblast was significantly increased at the end of active movement (Group III) and significantly very highly increased during the relapse period (Group IV). Regarding the ERM cells there were statistically significant increase in both the number of cells in each ERM cluster and the surface areas of the ERM clusters in Group III and highly significant increase in Group IV, while Group II showed no significant differences regarding all measurements. Conclusions: It was concluded that fibroblast and ERM cells may play an important role during orthodontic relapse
Background: This study aimed to use the combined mesio-distal crowns widths of maxillary incisors and first molars as predictors to the combined mesio-distal crowns widths of maxillary and mandibular canines and premolars. Materials and methods: The sample included 110 Iraqi Arab subjects with an age ranged between 17-25 years and class I skeletal and dental relations. The crown widths of maxillary teeth and mandibular canines and premolars were measured at the largest mesio-distal dimension on the study casts using digital electronic caliper with 0.01 mm sensitivity. Pearson’s correlation coefficient was used to determine the relation between the combined mesio-distal crowns widths of maxillary incisors and first molars and the combined
... Show MoreBackground: Periodontal diseases (PD) are common chronic inflammatory diseases caused by pathogenic microorganisms colonizing the gingival area and inducing local and systemic elevations of pro-inflammatory cytokines resulting in tissue destruction by a destructive inflammatory process. Stress was considered as one of the important risk factors that cause many inflammatory diseases including PD. The purpose of this study wasto determines and compares clinical periodontal parameters (PLI, GI and BOP), stress level and salivary IL-1? level among dental students before, during and after mid-year exam, also to find the correlation among stress, IL-1? and clinical periodontal parameters. Materials and methods: The sample was consisted of 24 dent
... Show MoreExcessive use of pesticides has led to increasing concern about undesirable effects on human health and the environment. Imidacloprid is an internationally used neonicotinoid insecticide due to its significant toxicity to insects. Its residues may reach the food chain, which is important for examining the potentially harmful properties of imidacloprid exposure. The current study aimed to characterize the histopathological effects of imidacloprid on the liver of male rabbits.
The Imidacloprid administration daily at the two chronic oral doses of (45 mg/kg and 90 mg/kg, daily) for 37 days. Treated male rabbits groups for treatment concentrations revealed many histopathological changes in the liver, such as congestion o
... Show MoreABSTRACT: BACKGROUND: Coriandrum Sativum is a native of Mediterranean region and is grown in North Africa, central Europe, and Asia as culinary herb and medicament. In addition to the other health-supporting reputation, coriander has hypoglycemic, hypolipidemic, and aphrodisiac effects. OBJECTIVE: To study the effect of Coriandrum Sativum on process of spermatogenesis. MATERIALS AND METHODS: Coriandrum sativum was given daily to mature male rats in a dose of 50mg/ 100g body weight for 14 days. 10% formalin fixed paraffin-embedded tissue sections were performed for histological and morphometrical studies. RESULTS: Histological study showed wider seminiferous tubules & increased spermatocytes population with an increased sperm density
... Show MoreBackground: Lamotrigine is a second generation Anti-epileptic drug; it is widely used for the treatment of epilepsy and bipolar disorder. Sufficient data is not available concerning its teratogenicity. Aim of the study: The study has been carried out to evaluate the effect of lamotrigine on Rat kidney development. Materials and Methods: The study was conducted on 10 pregnant Albino Rats (Rattus rattus) divided equally into two groups, control and experiment groups. Experiment group received lamotrigne 10mg/kg/day orally using naso-gastric tube from the first day of gestation until the first week after birth, while the control group received distilled water. Newborn kidneys were collected at day 7 postnatal and fixated in bouin’s solution,
... Show MoreThis work consists of a numerical simulation to predict the velocity and temperature distributions, and an experimental work to visualize the air flow in a room model. The numerical work is based on non-isothermal, incompressible, three dimensional, k turbulence model, and solved using a computational fluid dynamic (CFD) approach, involving finite volume technique to solve continuity, momentum and energy equations, that governs the room’s turbulent flow domain. The experimental study was performed using (1/5) scaled room model of the actual dimensions of the room to simulate room air flow and visualize the flow pattern using smoke generated from burnt herbs and collected in a smoke generator to delivered through
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