Polymerization behavior and thermal characteristics of two new composites at five temperatures: refrigeration to preheating

PURPOSE

Heat of composite polymerization (HP) indicates setting efficacy and temperature increase of composite in clinical procedures. The purpose of this in vitro experimental study was to evaluate the effects of 5 temperatures on HP of two new composites.

MATERIALS AND METHODS

From each material (Core Max II [CM] and King Dental [KD]), 5 groups of 5 specimens each were prepared and their total HPs (J/gr) were measured and recorded, at one of the constant temperatures 0℃, 15℃, 23℃, 37℃ and 60℃ (2 × 5 × 5 specimens) using a differential scanning calorimetry (DSC) analyzer. The data were analyzed using a two-way ANOVA, a Tukey''s test, an independent-samples t-test, and a linear regression analysis (α=0.05).

RESULTS

No polymerization reactions occurred at 0℃; then this temperature was excluded from statistical analyses. The mean HP of the remaining 20 KD specimens was 20.5 ± 14.9 J/gr, while it was 40.7 ± 12.9 J/gr for CM. The independent-samples t-test showed that there were significant differences between the HP of the two materials at the temperatures 15℃ (P=.0001), 23℃ (P=.0163), 37℃ (P=.0039), and 60℃ (P=.0106). Linear regression analysis showed statistically significant correlations between environment temperatures and HP of CM (R²=0.777).

CONCLUSION

Using CM is advantageous over conventional composite because of its better polymerization capacity. However due to its high HP, further studies should assess its temperature increase in vivo. Preheating KD is recommended. Refrigerating composites can negatively affect their polymerization potential.     

Acitretin-induced spiny follicular hyperkeratosis

Spiny follicular hyperkeratosis (SFH) is follicular flesh-colored hyperkeratotic spicules that are linked to different situations including drug reactions. Previously suspected drugs are BRAF inhibitors and cyclosporine. We described a 51-year-old psoriasis patient with SFH who had been using acitretin.     

Complex Genitourinary Duplication Affecting Neurourologic and Urodynamic Findings: Report of a Case and Review of the Literature

BackgroundComplete duplication of the bladder and urethra is a rare congenital anomaly and usually occurs in association with other organ anomalies. We report a case of complete bladder duplication associated with multiple non-genitourinary anomalies.CaseA 10-year-old girl presented with urinary incontinence and recurrent episodes of febrile urinary tract infections. Simultaneous right and left bladder urodynamic study was performed and revealed bilateral decreased bladder compliance associated with hyperreflexia. The patient underwent reconstructive surgery with combination of the 2 bladders and closure of the right incompetent bladder neck.Summary and conclusionManagement of bladder duplication is directed towards creating an unobstructed urinary tract, preventing infections, and achieving urinary continence. Neurourologic and urodynamic assessment is of utmost importance especially when concomitant spinal anomaly exists. Furthermore, these patients should be observed lifelong as alteration in bladder function may occur.     

Changes in liver enzymes and association with prognosis in patients with COVID-19: a retrospective case–control study

ObjectiveCOVID-19 has recently emerged as a serious threat to global health. This study examined the laboratory investigations of patients with COVID-19, with an emphasis on liver enzymes.MethodsThis retrospective, single-center study was performed on patients with COVID-19 who were admitted to Imam Reza Hospital, Iran from March 2020 to February 2021. Laboratory tests included a complete blood cell count, white blood cell (WBC) count, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio, and levels of aspartate aminotransferase, alanine aminotransferase (ALT), and alkaline phosphatase. Patient survival was among the outcome measures investigated in association with laboratory findings.ResultsWe enrolled 77 patients with COVID-19 and 63 healthy controls. In comparison with the control group, patients with COVID-19 showed COVID-19 increased ALT, WBC, neutrophils, NLR, and PLR, and decreased platelet counts and lymphocytes.ConclusionAlthough elevated levels of AST, NLR, PLR, and LMR were found in patients with COVID-19, they were not linked to mortality. Given the presence of AST in other tissues, the influence of SARS-CoV-2 on the liver should be interpreted with caution.