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<p><b>OBJECTIVE</b>To study the interleukin-8 (IL-8) levels in gingival crevicular fluid (GCF) of porcelain teeth coated with Ni-Cr, Co-Cr or gold alloy at different time periods, and to uncover the degree of stimulation by these alloys on gingiva at different time periods.</p><p><b>METHODS</b>45 cases of porcelain teeth coated with Ni-Cr, Co-Cr or gold alloy were selected randomly, with 15 cases in each group. Sandwich enzyme-linked immunosorbent assay (ELISA) was used to determine the concentration and total amount of IL-8 in GCF. The assay was done before treatment, as well as at 1, 3 and 6 months post-treatment.</p><p><b>RESULTS</b>The total amounts of IL-8 and GCF volume in the Ni-Cr alloy coated porcelain teeth were higher in different time period than those before treatment (P<0.05). However, the IL-8 levels in Co-Cr and gold alloy coated porcelain teeth returned to pre-dental restoration after 3 months. Otherwise, the levels of IL-8 concentration in GCF showed no significant difference among the three different alloys coating at different time periods.</p><p><b>CONCLUSION</b>IL-8 is an important cytokine during tissue inflammation. Therefore, the level of IL-8 in GCF is a useful criteria for the evaluation of stimulation degree on gingiva by different alloy coating materials in porcelain teeth. The clinical choice of different alloy coating for porcelain teeth should be considered accordingly.</p>
Subject(s)
Humans , Male , Alloys , Dental Porcelain , Gingiva , Gingival Crevicular Fluid , Interleukin-8 , Metal Ceramic Alloys , Tooth, ArtificialABSTRACT
Objective To investigate the changes in cerebral hemodynamics in different body positions in healthy volunteers.Methods Sixty right-handed healthy male volunteers,aged 22-26,height 167-178 cm,weighing 51-67 kg,were randomly divided into 4 groups ( n =15 each): 15 degrees head-down tilt group (group Ⅰ ),30 degrees head-down tilt group (group Ⅱ ),15 degrees head-up tilt group (group Ⅲ) and 30 degrees head-up tilt group (group Ⅳ ).Blood flow signals of right middle cerebral artery (MCA) and extracranial internal carotid artery (EICA) were detected by transcranial Doppler and systolic blood flow velocity (Vs),diastolic blood flow velocity (Vd ),mean blood flow velocity (Vm),pulsatility index (PI) and resistance index (RI) were recorded at supine position (baseline),immediately,10 and 30 min after body position change(T1-3 ).Lindegaard index was calculated.Results Compared with the baseline,in group [Ⅱ Lindegaard index was increased at T2,while Vs and Vm of MCA were decreased at T2,3,in group Ⅳ Vs of MCA and PI of EICA at T2,Vd and Vm of MCA at T2,3 were decreased ( P ＜ 0.05),while there was no significant difference in the variables mentioned above in the other two groups ( P ＞ 0.05 ).Conclusion In healthy adults,cerebral blood flow velocity decreases in 30 degrees headdown and head-up tilt positions,however there is no change in cerebral blood flow velocity in 15 degrees headdown and head-up tilt positions.
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@#Objective To investigate the changes of morphology of injured nerve after pulsed radiofrequency (PRF) and radiofrequency thermocoagulation (RFTC) on rats. Methods 55 male Wistar rats were selected, in which 5 were allocated to control group (group C) and the other 50 were randomly divided into group PRF (n=25) and group RFTC (n=25). The specimens were analyzed both with light microscopy and electron microscopy at immediate, and 1, 7, 14 and 28 d after operation. Results In group PRF, the nerve function of rats maintained after operation. The edema among nerve fibers was found under light microscope, while myelin lamellar structure disorder and myelin balls shaped, and compensatory hyperplasia of ultrastructure under electron microscopic level. Those effects were more pronounced 1 d after operation. In group RFTC, the nerve function of rats disappeared and autophagy behaviors happened, meanwhile Waller's degeneration and nerve regeneration appeared under both light microscopy and electron microscopy. Conclusion PRF and RFTC can produce destruction of nerve, but PRF was minor and recoverable.
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Objective:To study the expression of Ki67 and P53 proteins in gingival tissue after wearing four kinds of temporary crowns.Methods:The experiment animal model was established by temporary prosthesis on dogs' teeth using chemical-curing resin,thermal-curing resin,DMG-TEMP crown material and SWIFT composite resin respectively.The immunohistochemistry Envision method was used to measure the expression of Ki67 and P53 proteins in gingival tissue before tooth preparation,after tooth preparation,1-and 2-week,1 month after wearing the crowns.The teeth without any treatment were surved as control.HE stained gingival tissue slices were observed under microscope.Results:The expression of Ki67 and P53 proteins in gingival tissue increased 1 week after wearing the chemical-curing resin crowns or thermal-curing resin crowns(P0.05).No pathological change was observed in all the samples.Conclusion:Chemical-curing resin crowns and thermal-curing resin crowns may increase the expression of Ki67 and P53 proteins in gingival tissue,but DMG-TEMP crowns and SWIFT resin crowns do not.None of the four kinds of temporary crowns may cause abnormal proliferation of gingival epithelia.