in vitro evaluation of marginal leakage using invasive and noninvasive technique of light cure glass ionomer and flowable polyacid modified composite resin used as pit and fissure sealant.

Aim: This study compared the microleakage of light cure glass ionomer and flowable compomer as pit and fissure sealant, with and without tooth preparation. Materials and Methods: One hundred premolars that were extracted for orthodontic purpose were used. After adequate storage and surface debridement, the teeth were randomly divided into four groups. In Group I and III, the occlusal surfaces were left intact, while in Group II and Group IV, tooth surfaces were prepared. Teeth in Group I and Group II were sealed with Light cure glass ionomer, whereas flowable compomer was used to seal teeth in Group III and IV. The sealed teeth were then immersed in dye. Subsequently, buccolingual sections were made and each section was examined under stereomicroscope for microleakage followed by scoring. Results: In group I, microleakage score ranged from 2 to 4 with mean of 3.64 (±0.757), while in group II the range was observed to be 1-4 with mean of 2.88 (±1.236). Group III recorded a range of 0-4 with the mean of 2.20 (±1.443) while 0-2 and 0.60 (±0.707) being the range and mean observed, respectively, for group IV. Conclusion: Flowable compomer placed after tooth preparation showed better penetration and less marginal leakage than the light cure glass ionomer.

A study on the fetal umbilical artery doppler blood flow velocity waveforms in normal pregnancy / 영남의대학술지

Noninvasive techniques of antenatal detection of the fetal development and well-being such as biophysical profile, non-stress and stress remain major challenges in modern obstetric practice. To obtain and analyze umbilical artery velocity waveform by pulsed-wave doppler ultrasound, a total of 160 determinations were carried out on 157 normal pregnant women between 16th to 41st week gestation. The ratio of peak systolic to end-diastolic flow velocity (S/D ratio), pulsatility index and resistance index were measured as indices of the resistance in feto-placental circulation. The results were as follows: As gestation advances, the mean values for peak systolic and end-diastolic velocities raised progressively. As gestation advances, the mean values for the S/D ratio declined progressively, exhibiting high diastolic flow velocity caused by low resistance. Pulsatility index, and resistance index were also declined progressively, as gestation advances. The analysis of umbilical artery blood flow velocity waveforms provides a new noninvasive technique to evaluate fetal development and well-being, and may be expected a reliable method for assessment of fetal life.