The aim of this study was to examine that thick dentin bonding agent application or low modulus composite restoration could reduce stresses on dentin bonding agent layer. A mandibular first premolar with abfraction lesion was modeled by finite element method. The lesion was restored by different composite resins with variable dentin bonding agent thickness (50microm, 100microm, 150microm). 170N of occlusal loading was applied buccally or lingually. Von Mises stress on dentin bonding agent layer were measured. When thickness of dentin bonding agent was increased von Mises stresses at dentin bonding agent were decreased in both composites. Lower elastic modulus composite restoration showed decreased von Mises stresses. On root dentin margin more stresses were generated than enamel margin. For occlusal stress relief at dentin boning agent layer to applicate thick dentin bonding agent or to choose low elastic modulus composite is recommended.
Bicuspid ; Composite Resins ; Dental Enamel ; Dentin ; Elastic Modulus

OBJECTIVE: To evaluate pregnancy outcomes after electrosurgical conization. METHODS: We retrospectively analyzed the outcomes of 56 singleton pregnancies after electrosurgical conization of the uterine cervix. Of the 56 cases, 25 women underwent prophylactic cerclage with McDonald procedure (cerclage group), and 31 were managed expectantly (expectant group). Pregnancy outcomes including rate of preterm delivery were compared, and the effect of potential risk factors such as depth of cone, interval between conization and pregnancy, and cervical length on the risk of preterm delivery was assessed. RESULTS: The rate of preterm delivery was significantly higher in women with a history of electrosurgical conization than those without (32.1% vs. 15.2%, p<0.001). However, preterm delivery rate was not different between the two groups (expectant group vs. cerclage group; <28 week, 6.5% vs. 8.0%, p=1.000; <34 week, 19.4% vs. 20.0%, p=1.000; <37 week, 29.0% vs. 36.0%, p=0.579). All obstetric and neonatal outcomes were similar in the two groups. Even when we confined the study subjects to 19 women (19/56, 33.9%) with cervical length less than 25 mm, the preterm delivery rate also was not significantly different between the expectant (n=7) and cerclage group (n=12). Finally, the potential risk factors for preterm delivery were not associated with risk of preterm delivery in patients with a history of electrosurgical conization. CONCLUSION: The rate of preterm delivery was significantly higher in women with a history of electrosurgical conization before pregnancy. However, prophylactic cervical cerclage did not prevent preterm delivery in these patients.
Cerclage, Cervical ; Cervix Uteri ; Conization ; Female ; Humans ; Pregnancy ; Pregnancy Outcome ; Premature Birth ; Retrospective Studies ; Risk Factors

The effect of mannitol on serum osmolality(Sosm) was studied in 13 patients with increased intracranial pressure(Group I ) and 14 normal men(GroupII ). All of the Patients in Gtoup I were given 0.5 g/kg dose of mannitol radipidly and blood samples for Sosm were taken at 30 rninutes intetvals for the first one hour and at hourly intervals for the next 5 hours after mannitol infusion. Seven of Group II(Iia) received 0.5 g /kg dose of mannitol and the other 7 ( II b) received 1.0 g / kg, Blood samples for Sosm and electrolytes were taken at the same intervals for the same duration as in Group I expept for additionai blood samples every 5 rninutes during the first 30 minutes. In Group I there was no significant rise in Sosm even 30 minutes after mannitol infusion. In Group Iia and Iib, a maximum increase of 6 mOsm / kg, 14 mOsm / kg was observed at about 5 minutes, 25 minutes after mannitol infusion respectiveiy, which returned to baseline in about 1 hour and 4 hours respectively. The 1.0g /kg dose of mannitol produced a significant and relatively persistent increase in Sosm probably enough to reduce the ICP, but at dose of 0.5 g / kg there was minimal increase in Sosm; which seemed to be insufficient to reduce the ICP significantly as claimed in previous reports that there must be a Sosm rise of at least 10 mOsm / kg to have a significant reduction in ICP. Also, to detemine the loss of water and electrolytes through urine after mannitol administration, the urine volume and electrolytes were measeured at 30 minutes intervals for the first one hour and then every hour thereafter for six hours in normal men(Group II). Water and electrolytes excretion rates and urinary sodium concentrations were calculated in each interval. The author believes that these data would be useful in estimating the amount of water and electrolytes that has to be replaced.
Electrolytes* ; Humans ; Mannitol* ; Osmolar Concentration* ; Sodium

To investigate the expressions of Fas and Fas ligand (FasL) in human placenta, we studied the expressions of Fas and FasL in placenta with RT-PCR, immunoblotting and immunostaining. We observed amplified products of Fas and FasL transcripts, the band of Fas (52 kDa) and multiple bands of FasL (42-52 kDa) in pla-centa. Fas and FasL localized mainly on fetal vessels and on syncytiotrophoblasts respectively. The differential distribution of Fas and FasL in human placenta may reflect intrinsic expressions of them by trophoblasts during differentiation. The increased expression of Fas in trophoblasts may promote apoptosis of placenta in pathologic condition such as preeclampsia.
Antigens, CD95/biosynthesis/*genetics ; Fas Ligand Protein ; *Gene Expression ; Gene Expression Profiling ; Glycosylation ; Humans ; Immunoblotting/methods ; Membrane Glycoproteins/biosynthesis/*genetics ; Placenta/*metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Trophoblasts/cytology/metabolism