Effect of colored beverages on the color stability of feldspathic porcelain subjected to various surface treatments

Objective: To investigate the effects of porcelain treatment techniques on the color change of feldspathic porcelain before and after exposure to distilled water, coffee, red wine, and cola and examine the surface texture of the porcelain with field-emission SEM. Materials and Methods: Test specimens were prepared in the form of discs 15 mm in diameter by 2-mm think and divided into four groups: Naturalglaze, dual-ion-exchange, overglaze, and polishing. The specimens were prepared according to their group and stored in red wine, coffee, or cola. After removal, the specimens were dipped in distilled water. Color measurements were made with a spectrophotometer, and color differences were determined using the CIE L * a * b system. Statistical analysis was made with SPSS 13.5. Results: Immersion time and types of surface treatment were significant factors for color stability (P < .01). Conclusions: All surface treatment groups deomonstrated color change at or below a quantitative level that would be considered clinically acceptable. (Quintessence Int 2009; 40: e41-e48

Electrocardiographic changes in primary spontaneous pneumothorax

WOS: 000339225600019Background: This study aims to evaluate the electrocardiographic (ECG) changes in patients with primary spontaneous pneumothorax. Methods: A total of 48 patients (42 males, 6 females; mean age 29.7 +/- 12.5 years, range 15 to 58 years) with PSP were prospectively analyzed between November 2010 and November 2011. Pneumothorax size was calculated using the Rhea method. At least two standard 12-lead ECG were obtained for each patient (after the diagnosis of pneumothorax and prior to drain placement - ECG(pneumothorax), and after a complete re-expansion of the lung was achieved and confirmed radiologically - ECG(re-expanded)). P wave measurement, PR distance, QRS distance, QT interval and QT interval corrected for heart rate (QTc) were calculated. Heart rate (bpm), axis deviation measurement and the QRS amplitudes (QRSV1-6) in precordial leads were calculated. Results: There were 29 cases (60.4%) of left-sided and 19 cases (39.6%) of right-sided pneumothorax. The mean relative volume of pneumothorax was 43.0 +/- 21.5%. The most common symptoms included chest pain in 34 patients (70.8%) and dyspnea in 14 patients (29.2%). The pneumothorax duration was 24 hours in 18 patients (37.5%). There was a statistically significant difference between before and after the treatment for QT duration, axis deviation, heart rate, QRSV1, QRSV4, QRSV5 and QRSV6 (respectively; p=0.001, p=0.023, p=0.001, p=0.010, p=0.046, p=0.000, p=0.008). A total of seven patients had relevant QRS abnormalities including incomplete right bundle branch block in three patients, ST elevation in two patients and T-wave pointedness in one patient. Conclusion: Our study results suggest that left and right lung pneumothorax may cause axis variation, which is more pronounced in women, and that voltage increases after drainage in QRSV 4, 5 and 6 leads. In addition, pneumothorax may lead to specific ECG variations such as right bundle branch block and ST variations