Category: Nevin Manimala

Am J Dent. 2021 Apr;34(2):91-96.

ABSTRACT

PURPOSE: To evaluate and compare the flexural strength of three CAD-CAM glass-ceramic materials and to investigate the effect of various surface treatments on their flexural strength.

METHODS: 120 rectangular specimens were fabricated from three different types of CAD-CAM ceramic blocks and were divided into three groups: zirconia-reinforced lithium silicate (Celtra Duo, Group 1), leucite-reinforced glass-ceramic (IPS Empress CAD, Group 2), and lithium disilicate ceramic (IPS e.max CAD, Group 3). Dimensions of the specimens were standardized to 14.5×12.5 mm and 1.5 mm thickness. Specimens in each group were randomized into four subgroups. The first subgroup (NS) did not undergo any surface treatment; the second subgroup (P) underwent polishing only; the third subgroup (G) underwent glazing only; and the fourth subgroup (PG) underwent both polishing and glazing surface treatments. Biaxial flexural strength (FS) testing was performed until fracture occurred; FS was calculated in MPa. All analyses were performed using SPSS version 24.

RESULTS: Group NS2 showed the lowest FS (89.34 ± 25.30 MPa). Group PG3 showed a significantly higher FS (365.38 ± 52.52 MPa) than Group P3 (268.15 ± 48.34). There was a statistically significant difference among the material groups for each surface treatment: IPS e.max CAD showed the highest FS, which was significantly greater than that of both Celtra Duo and IPS Empress CAD. The combination of polishing and glazing surface treatment resulted in significantly higher flexural strength than polishing alone for all three materials tested. For each material, no significant difference was found between the following surface treatments: control and polishing-only surface treatments; glazing-alone and the combination of polishing and glazing surface treatments. For each surface treatment, Celtra Duo showed significantly lower flexural strength than IPS e.max CAD. However, it displayed higher flexural strength than IPS Empress CAD, although the difference was only significant for glazing and the combination of polishing and glazing.

CLINICAL SIGNIFICANCE: This study provides the clinician with an estimate of the flexural strength of glass-ceramic materials and shows how various surface treatments affect their strength.

PMID:33940666

Am J Dent. 2021 Apr;34(2):101-104.

ABSTRACT

PURPOSE: To evaluate and describe the most frequent TMJ degenerative bone alterations on MRI and CT and to determine the accuracy, sensitivity, and specificity of MRI.

METHODS: Images of 80 subjects were selected and evaluated from a database and 57 were selected. The subjects were submitted to CT and MRI exams (each subject on the same day). The joints were evaluated in the sagittal and coronal planes under closed mouth position. Each individual parameter was scored as absent or present. Absolute and relative frequencies were obtained and the Kappa concordance index test and equality of two proportions were used. To correlate the presence of bone alterations, the Chi-Square test was performed. A significance level of 0.05 (5%) was defined, with 95% of statistical confidence interval.

RESULTS: Of the 57 subjects, (47 female, 10 male), the ages ranged from 18-83 years (mean 43 years). The intra and inter-rater agreement tests demonstrated reliability among the examiners for all variables analyzed on MRI and CT.

CLINICAL SIGNIFICANCE: MRI is a reliable and valid method for observing bone changes in the TMJ, with the advantage of non-exposure to radiation and cost-effectiveness due to the use of only one exam.

PMID:33940668

Tuberc Respir Dis (Seoul). 2021 Mar 24. doi: 10.4046/trd.2021.0016. Online ahead of print.

ABSTRACT

BACKGROUND: The Korea National Health and Nutrition Examination Survey (KNHANES) is a well-designed survey to collect national data, which many researchers have used for their studies. In KNHANES, although portable spirometry was used, its reliability has not been verified.

METHODS: We prospectively enrolled 58 participants from four Korean institutions. The participants were classified into normal pattern, obstructive pattern, and restrictive pattern groups according to their previous spirometry results. Lung function was estimated by conventional spirometry and portable spirometry, and the results were compared.

RESULTS: The intraclass correlation coefficients of forced vital capacity (FVC) (coefficient, 9.993; 95% confidence interval [CI], 0.988-0.996), forced expiratory volume in 1 second (FEV1) (coefficient, 0.997; 95% CI, 0.995-0.998), FEV1/FVC ratio (coefficient, 0.995; 95% CI, 0.992-0.997), and forced expiratory flow at 25-75% (FEF25-75%; coefficient, 0.991; 95% CI, 0.984-0.994) were excellent (all p<0.001). In the subgroup analysis, the results of the three parameters were similar in all groups. In the overall and subgroup analyses, Pearson’s correlation of all the parameters was also excellent in the total (coefficient, 0.986-0.994; p<0.001) and subgroup analyses (coefficient, 0.915-0.995; p<0.001). In the paired t-test, FVC, FEV1/FVC, and FEF25-75% estimated by the two instruments were statistically different. However, FEV1 was not significantly different.

CONCLUSION: Lung function estimated by portable spirometry was well-correlated with that estimated by conventional spirometry. Although the values had minimal differences between them, we suggest that the spirometry results from the KNHANES are reliable.

PMID:33940672 | DOI:10.4046/trd.2021.0016

Am J Perinatol. 2021 May 3. doi: 10.1055/s-0041-1727167. Online ahead of print.

ABSTRACT

OBJECTIVE: The study aimed to examine the incidence of hypertensive disorders of pregnancy in women diagnosed with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2, also known as COVID-19).

STUDY DESIGN: This was a retrospective cohort study of all women who delivered at MedStar Washington Hospital Center in Washington, DC from April 8, 2020 to July 31, 2020. Starting April 8, 2020, universal testing for COVID-19 infection was initiated for all women admitted to labor and delivery. Women who declined universal testing were excluded. Hypertensive disorders of pregnancy were diagnosed based on American College of Obstetricians and Gynecologists Task Force definitions.1 Maternal demographics, clinical characteristics, and labor and delivery outcomes were examined. Neonatal outcomes were also collected. Laboratory values from admission were evaluated. Our primary outcome was the incidence of hypertensive disorders of pregnancy among women who tested positive for COVID-19. The incidence of hypertensive disorders of pregnancy was compared between women who tested positive for COVID-19 and women who tested negative.

RESULTS: Of the 1,008 women included in the analysis, 73 (7.2%) women tested positive for COVID-19, of which 12 (16.4%) were symptomatic at the time of admission. The incidence of hypertensive disorders of pregnancy was 34.2% among women who tested positive for COVID-19 and 22.9% women who tested negative for COVID-19 (p = 0.03). After adjusting for race, antenatal aspirin use, chronic hypertension, and body mass index >30, the risk of developing any hypertensive disorder of pregnancy was not statistically significant (odds ratio: 1.58 [0.91-2.76]).

CONCLUSION: After adjusting for potential confounders, the risk of developing a hypertensive disorder of pregnancy in women who tested positive for COVID-19 compared with women who tested negative for COVID-19 was not significantly different.

KEY POINTS: · There is an increased incidence of hypertensive disorders in women who test positive for COVID-19.. · Characteristics of pregnant women with COVID-19 are similar to those with hypertensive disorders.. · Liver function tests were similar between pregnant women with COVID-19 and women without COVID-19..

PMID:33940651 | DOI:10.1055/s-0041-1727167

Am J Dent. 2021 Apr;34(2):87-90.

ABSTRACT

PURPOSE: To assess the gingivitis reduction efficacy of a novel stannous-containing fluoride dentifrice relative to a negative control.

METHODS: 100 generally healthy adults with 10 or more gingival bleeding sites based on the Mazza Modification of the Papillary Bleeding Index (Mazza GI) were enrolled into a 2-week randomized, controlled, double-blind, single-center, two-treatment, parallel group clinical study. The subjects were randomly assigned to the stannous-containing dentifrice group (experimental group) or the sodium fluoride dentifrice group (negative control group). An oral examination and Mazza GI examination were conducted at Baseline, Day 3 and Week 2 post-baseline by a qualified dental examiner.

RESULTS: 98 subjects completed the study. The experimental group provided a significant reduction in Mazza GI scores and number of bleeding sites relative to baseline at Day 3 and Week 2 (P< 0.0001). The negative control did not provide significant reductions versus baseline for either measure at either timepoint (P> 0.3). At Day 3, the experimental group provided a statistically significant reduction of Mazza GI scores and number of bleeding sites compared with the negative control group (P< 0.0001). At Week 2, the experimental group showed 24.11% lower Mazza GI scores and 54.81% fewer bleeding sites than the negative control group (P< 0.0001).

CLINICAL SIGNIFICANCE: The results demonstrated that the novel stannous-containing fluoride dentifrice had a superior anti-gingivitis effect compared to the sodium fluoride negative control dentifrice, which was evident as quickly as 3 days after use and further improved after 2 weeks of usage.

PMID:33940665

Am J Perinatol. 2021 May 3. doi: 10.1055/s-0041-1728826. Online ahead of print.

ABSTRACT

OBJECTIVE: Postpartum hypertension (PP-HTN), defined as systolic/diastolic blood pressure (SBP/DBP) ≥140/90, on two occasions at least 4 hours apart after delivery occurs in up to 50% of preeclamptic pregnancies, and is associated with adverse maternal outcomes. Excessive production of antiangiogenic factors (i.e., soluble fms-like tyrosine kinase 1 [sFLT1]) and reduced levels of proangiogenic factors (i.e., placental growth factor [PlGF]) are associated with preeclamptic pregnancies. The aim of this study was to identify clinical risk factors and/or serum biomarkers associated with PP-HTN in preeclampsia.

STUDY DESIGN: Preeclamptic women (n = 82, aged ≥18 years) were prospectively enrolled in an observational study. Serial blood pressures were obtained through the labor course and until 48 hours postpartum, and serum was obtained within 24 hours postpartum. Statistical analysis was performed by using Student’s two-tailed t-test and Fisher’s exact test.

RESULTS: Baseline comorbidities and antihypertensive use were similar among those who developed PP-HTN and those who did not. Among preeclamptic patients, 33% developed PP-HTN; these had significantly more severe preeclampsia features versus no PP-HTN (96 vs. 78%, p = 0.05). PP-HTN was associated with higher re-hospitalization rates (26 vs. 6%, p = 0.01). Among those taking low-dose aspirin (ASA) for preeclampsia prophylaxis (n = 12), PP-HTN was significantly less frequent versus those not taking low-dose ASA (0 vs. 22%, p = 0.007). Low-dose ASA use was associated with significantly lower peripartum sFLT1 levels (4,650 ± 2,335 vs. 7,870 ± 6,282 pg/mL, p = 0.03) and sFLT1/PlGF ratio (397 ± 196 vs. 1,527 ± 2,668, p = 0.03).

CONCLUSION: One-third of women with preeclampsia develop PP-HTN; these patients have more severe preeclampsia and have higher re-hospitalization rates. Prenatal low-dose ASA use was associated with significantly lower incidence of PP-HTN, reduced levels of antiangiogenic factors, and lower 6-week re-hospitalization rates. These findings, if replicated, may have clinical implications on the use of low-dose ASA during pregnancy to reduce incidence of postpartum HTN.

KEY POINTS: · Postpartum hypertension is common in preeclampsia.. · Prenatal aspirin may reduce postpartum hypertension.. · Prenatal aspirin may reduce sFLT1 levels..

PMID:33940641 | DOI:10.1055/s-0041-1728826

Clin Imaging. 2021 Apr 29;79:125-132. doi: 10.1016/j.clinimag.2021.04.013. Online ahead of print.

ABSTRACT

RATIONALE AND OBJECTIVES: To evaluate the diagnostic performance of abbreviated MRI (AB-MRI) in comparison to a full protocol MRI (FP-MRI) when evaluating common MRI abnormalities of a mass, non-mass enhancement and focus.

MATERIALS AND METHODS: This retrospective reader study was Institutional Review Board approved and Health Insurance Portability and Accountability Act (HIPAA) compliant. AB-MRIs were reviewed from May 2018-December 2019 to identify women with an abnormal AB-MRI, FP-MRI within six months of the AB-MRI and an elevated risk for breast cancer. Six breast radiologists initially interpreted and recorded findings from the AB-MRI. Immediately after reviewing the AB-MRI, the same radiologists interpreted and recorded findings from the FP-MRI. Findings were recorded in an electronic data collection form. Cohen’s Kappa test was used to calculate agreement. P < 0.05 was considered statistically significant.

RESULTS: Of 119 patients who had an AB-MRI, our final study comprised of 32 patients who had 64 breast MRIs (32 AB-MRI and 32 FP-MRI). The amount of fibroglandular tissue for AB-MRI and FP-MRI showed excellent intra-reader agreement [Kappa: 0.89-1.00 (P < 0.0001)]. Substantial to excellent intra-reader agreement [Kappa: 0.74-0.93 (P < 0.0001)] was demonstrated for all 6 readers when identifying abnormalities seen on AB-MRI and FP-MRI. Moderate to excellent intra-reader agreement [Kappa: 0.41-0.87(P < 0.0001)] was demonstrated between the AB-MRI and FP-MRI for the final BI-RADS assessment.

CONCLUSION: AB-MRI has acceptable intra-reader agreement with FP-MRI when characterizing common MRI abnormalities such as a mass, non-mass enhancement and focus suggesting that subsequent FP-MRI may not be needed.

PMID:33940489 | DOI:10.1016/j.clinimag.2021.04.013

Clin Imaging. 2021 Apr 29;79:136-141. doi: 10.1016/j.clinimag.2021.04.028. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of the current study was to classify and analyze trends in lumbar disc degeneration across age, sex, and disc level using weightbearing kinematic MRI.

MATERIALS AND METHODS: Between January 2019 and July 2019, 1198 cases were retrospectively analyzed with kinematic MRI. Patients were divided into 5 groups based on age (20-29, 30-39, 40-49, 50-59, and 60+) and evaluated using the Pfirrmann classification to assess for disc degeneration at 5 vertebral levels: L1/2, L2/3, L3/4, L4/5, and L5/S1. Trends in degeneration were analyzed with regression and time series.

RESULTS: The L5/S1 vertebral disc had the highest prevalence of severe degeneration across all age groups. The most common multi-level degeneration combinations were L4/5 and L5/S1 for two levels and L3/4, L4/5, and L5/S1 for three levels. All vertebral levels showed significant difference in mean Pfirrmann grade among the age groups (p < 0.001 at all levels). Statistically significant differences in mean Pfirmmann grade among males and females were found only in ages 20-29 and 30-39, in which males showed more degeneration.

CONCLUSION: Our findings using kinematic MRI demonstrate that degeneration increases with age and is most severe in the L5/S1 disc. In multi-level degeneration the most prevalent combinations are those that are contiguous and include L5/S1. Young males were more likely to have degeneration than young females, but there was no significant difference from the fifth decade of life on.

PMID:33940491 | DOI:10.1016/j.clinimag.2021.04.028

Radiat Prot Dosimetry. 2021 May 3:ncab066. doi: 10.1093/rpd/ncab066. Online ahead of print.

ABSTRACT

The purpose of the present work was to evaluate the use of resampling statistical methods for analysis of visual grading data-implemented in the software VGC Analyzer-by comparing the reanalyzed results from previously performed visual grading studies with the results calculated by gold standard receiver operating characteristic (ROC) methodology, Obuchowski-Rockette (OR)-Dorfman-Berbaum-Metz (DBM) multiple-readers and multiple-case (MRMC) and by analysis of simulated visual grading data where the true distribution was presumed to be known. The reanalysis was performed on two multiple-reader studies with non-paired data and paired data, respectively. The simulation study was performed by simulating a large number of visual grading characteristics (VGC) studies and by analyzing the statistical distribution of null hypothesis (H0) rejection rate. The comparison with OR-DBM MRMC showed good agreement when analyzing non-paired data for both fixed-reader and random-reader settings for the calculated area under the curve values and the confidence intervals (CIs). For paired data analysis, VGC Analyzer showed significantly lower CIs compared with the ROC software. This effect was also illustrated by the simulation study, where the VGC Analyzer, in general, showed good accuracy for simulated studies with stable statistical basis. For simulated studies with unstable statistics, the accuracy in the H0 rejection rate decreased. The present study has shown that resampling methodology can be used to accurately perform the statistical analysis of a VGC study, although the resampling technique used makes the method sensitive to small data sets.

PMID:33940628 | DOI:10.1093/rpd/ncab066

Clin Biomech (Bristol, Avon). 2021 Apr 27;85:105364. doi: 10.1016/j.clinbiomech.2021.105364. Online ahead of print.

ABSTRACT

BACKGROUND: Pes planovalgus is common in children with cerebral palsy. Although severity influences treatment, there still lacks standard clinical measurements to objectively quantify pes planovalgus in this population. The comparison of pedobarographic data and radiographic measurements to clinical evaluation has not been reported in this population.

METHODS: 395 feet were identified from a population of ambulatory pediatric patients with cerebral palsy. Each patient initially underwent clinical evaluation by an experienced physical therapist who classified feet as: 136 controls, 116 mild, 100 moderate, and 43 severe pes planovalgus. Quantitative measurements were then calculated from antero-posterior and lateral radiographs of the foot. Pedobarographic analysis included the arch index, center of pressure index, and a newly defined medial index.

FINDINGS: A multivariate analysis was performed on the radiographic and pedobarographic measurements collected. It identified seven variables that improved objective classification of pes planovalgus severity when utilized together. These include the foot progression angle, initial contact force, arch index, medial index, antero-posterior talonavicular coverage, lateral calcaneal pitch and lateral Meary’s angle. While the lateral calcaneal pitch angle statistically differed amongst all severity classes, no pedobarographic value statistically differed between all severity classes.

INTERPRETATION: Overall, the combination of radiographic and pedobarographic measurements provides valuable information for objectively classifying severity of pes planovalgus in children with cerebral palsy by utilizing these values together rather than independently. In a clinical setting, radiographs and pedobarographic data may be obtained to enhance assessment of severity and guide treatment.

PMID:33940478 | DOI:10.1016/j.clinbiomech.2021.105364