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Objective:
The aim of this study was to evaluate chromatic alterations in human tooth crowns induced by a Mineral Trioxide Aggregate-based sealer (MTA Fillapex® and a commonly used ZnOE-based sealer (Roth-811). The tested null hypothesis was that the application of the materials did not induce clinically perceptible crown discoloration (Ho: CIE color difference ΔE<3.7).Material and Methods:
Forty five fully developed, intact, mandibular third molars were sectioned 1 mm below the cemento-enamel junction. The pulp chambers were chemomechanically debrided via the cervical access. The specimens were randomly assigned into three groups Group 1: MTA Fillapex, Group 2: Roth 811, Group 3: Negative control (unfilled) and immersed in individually marked vials containing distilled water up to the cervix (37±1º C). The spectral reflectance lines were recorded by utilizing a UV-VIS spectrophotometer equipped with integration sphere in the visual spectrum at baseline, 1 week, 1 and 3 months after material placement. Data were transformed into values of the CIE L*a*b* color system and the corresponding ΔE values were calculated. Statistical analysis was performed using two-way mixed ANOVA models, at p=0.05 level of significance.Results:
A statistically significant increase in a* and b* chromatic parameters of the MTA Fillapex Group was measured. However, ΔE values did not exceed the human eye perceptibility threshold (set at ΔE<3.7) during the experimental period (ΔEt3=2.88). In Roth-811 Group, a statistically significant decrease in L* and a statistically significant increase in a* and b* chromatic parameters was measured, during all observation periods. Resultant ΔE values exceeded the human eye perceptibility threshold after 1 week (ΔEt1=5.65).Conclusions:
Application of MTA Fillapex in tooth crowns resulted in minimal color alterations, while Roth 811 induced severe discoloration, in vitro. It could be suggested that, in terms of aesthetics, the use of MTA Fillapex appears to be favorable. 相似文献Purpose
Hallux valgus is a complex deformity of the first metatarsophalangeal joint, with varus angulation of the first metatarsal, valgus deviation of the great toe and lateral displacement of the sesamoids and the extensor tendons. The aim of the surgery is to achieve correction of the varus deviation of the 1st metatarsal which is considered by some as the primary intrinsic predisposing factor to hallux valgus deformity.Methods
We retrospectively reviewed 85 patients (107 feet) who underwent an opening wedge osteotomy of the 1st metatarsal for correction of moderate to severe hallux valgus and metatarsus primus varus. A medially applied anatomic pre-contoured locking plate was used for fixation of the osteotomy.Results
The mean IMA was decreased from 15.8 (range 12–22) degrees to 7.8 (range 0–12) degrees. The mean pre-operative HVA was 39 (range 21–52) degrees and the mean postoperative HVA was 11.8 (6–19) degrees. The pre-operative AOFAS score was 52 (SD 3.1) and the postoperative score was 85 (SD 5.2).Conclusion
The proximal opening wedge metatarsal osteotomy is a safe, effective and reproducible technique for correction of moderate to severe hallux valgus deformity. The use of a locking plate provides enough control at the fragments, enhancing healing of osteotomy and maintenance of the correction even with a violated proximal lateral cortex. 相似文献Introduction and hypothesis
A significant proportion of patients develop voiding dysfunction after midurethral tape (MUT) insertion, which reduces patient satisfaction. The study’s purpose was to identify predictive factors of voiding dysfunction after a retropubic MUT procedure.Methods
This was a retrospective study of 100 patients who underwent only a retropubic MUT procedure between January 2010 and December 2011. Early voiding dysfunction was defined when patients required a Foley catheter within 48 h. Data including demographic information, urogenital symptoms, previous surgery, preoperative uroflowmetry and urodynamic parameters were analysed using SPSS v22. Univariate analysis of all demographic variables was performed; those significant at 10 % were entered into a multivariate logistic regression.Results
Fourteen patients required Foley catheter insertion, with a median age of 58 years (26–83 years), median BMI 28 kg/m2 (20–48 kg/m2), and median parity 2 (0–4). Univariate analysis revealed peak flow rate <15 ml/s (OR 3.79; 1.07, 13.4; p?=?0.046), bladder capacity (p?=?0.044), stress incontinence versus mixed or urge incontinence (p?=?0.064) and previous surgery (OR 4.39; 1.34, 14.41; p?=?0.015) to be associated with voiding dysfunction. Multivariate analysis showed only previous pelvic floor surgery to be independently associated (OR 3.76; 1.14, 12.23, p?=?0.029).Conclusions
Only previous pelvic-floor surgery was found to be a strong predictive factor of voiding dysfunction. The rate of voiding dysfunction was similar to those of published data. Previous studies revealed different predictive factors. A larger cohort is needed to provide a definite answer. Those with previous surgery appear to be those most at risk and pre-surgical counselling for these women could be suggested.Introduction
Pelvic Organ Prolapse Quantification (POP-Q) system, measured in centimetres using a ruler (e.g. POPstix®), is recommended to quantify prolapse severity. POPstix® are costly (US $1/ruler). Home-made devices are used instead, but these have not been shown to be reproducible.Hypothesis
Digitally assessed POP-Q (DPOP-Q) is as reliable, reproducible and acceptable as POP-Q assessed using POPstix®.Methods
In this randomised crossover diagnostic agreement trial, each assessor measured the index finger of their dominant hand using a ruler. At visit one, patients were randomised to either POPstix® POP-Q assessment in a modified lithotomy position or DPOP-Q in both modified a lithotomy and a standing position. After the first clinician conducted this assessment, a second blinded clinician then carried out the remaining assessment on the same patient. For each examination, duration was recorded, along with a patient-completed discomfort score. Twenty-five women were invited for visit two, at which DPOP-Q was recorded by the same clinician who undertook DPOP-Q at the first visit. This allowed evaluation of inter- and intraobserver agreement together with examination acceptability.Results
One hundred and nine women were recruited [median age 55 years, parity 2, body mass index (BMI) 27.1]. Of the 25 patients invited, 23 returned for visit two. DPOP-Q had high interobserver reliability [κ?=?0.94, 95 % confidence interval (CI) 0.878–0.996] and intraobserver reliability (α?=?0.96) with POPstix®. DPOP-Q was significantly quicker (p?=?0.02) and less uncomfortable (p?<?0.01) than POPstix® POP-Q.Conclusion
DPOP-Q is reliable, acceptable and cost effective.Scientific data regarding intravenous iron supplementation in peritoneal dialysis (PD) patients are scarce. In attempting to administer the minimum monthly IV iron dose that could improve erythropoiesis, we wanted to assess the safety and efficacy of monthly maintenance intravenous administration of 100 mg iron sucrose in PD patients.
MethodsIn a 9-month prospective study, all clinically stable PD patients received intravenously 200 mg of iron sucrose as a loading dose, followed by monthly doses of 100 mg for five consecutive months. Levels of hemoglobin (Hb), ferritin, transferrin saturation (TSAT), reticulocyte hemoglobin content (CHr) and C-reactive protein (CRP) were measured before each administration and 3 months after the last iron infusion. Also, doses of concurrent erythropoietin administration were recorded.
ResultsEighteen patients were eligible for the study. Mean levels of Hb and ferritin increased significantly (from 10.0 to 10.9 mg/dL, p?=?0.01 and from 143 to 260 ng/mL, p?=?0.005), as well as the increase in TSAT levels approached borderline significance (from 26.2 to 33.1%, p?=?0.07). During the 6 months of iron administration, the erythropoietin dose was reduced in five patients and discontinued in one. During the 3 months following the last iron infusion, three of them again raised the erythropoietin dose to previous levels. None of the patients experienced any side effects related to IV iron administration.
ConclusionsA monthly maintenance intravenous dose of 100 mg iron sucrose may be a practical, effective, and safe in the short term, treatment of anemia in PD patients resulting in improved hemoglobin levels, iron indices, and erythropoietin response.
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