Tag: statistics

J Adhes Dent. 2021 Jul 23;23(4):319-326. doi: 10.3290/j.jad.b1367933.

ABSTRACT

PURPOSE: To compare the effect of different methods of cleaning residual composite cement from the surface of lithium-disilicate glass-ceramic on its bond strength.

MATERIALS AND METHODS: Blocks of lithium-silicate glass-ceramic (e.max CAD) were coated with composite cement. Blocks in a positive control (CO+) group received no cement; negative controls (CO-) received composite cement. After water storage (24 h), specimens were cleaned as follows (n = 20/group): BUR: grinding with a fine-grit diamond bur (20 s); ALUM: air abrasion with 50-µm alumina (10 s); GLASS: air abrasion with 50-µm glass beads (10 s); FURN: firing in ceramic furnace and cleaning with ethanol; SULF: immersion in sulfonic acid solution (1 h); HYFL: no additional treatment. All specimens were etched with hydrofluoric acid, aside from the CO- group, and treated with silane. A 1.5-mm diameter cement-filled tube was affixed to the specimens and light polymerized. Specimens were stored in 37°C water for 24 h (n = 10) or 90 days (n = 10). Shear bond strength was tested. Two-way ANOVA and post-hoc Tukey tests were performed. Specimens from each group were examined with SEM.

RESULTS: Bond strength significantly differed according to surface cleaning method (p < 0.01) and storage time (p < 0.01), but their interaction was not significant (p = 0.264). Longer storage time decreased the bond strength. BUR, ALUM, GLASS, and FURN did not differ statistically significantly from CO+, but were significantly greater than CO-. SULF and HYFL did not differ statistically significantly from CO- and were significantly lower than CO+.

CONCLUSIONS: Cleaning composite cement with BUR, ALUM, GLASS, and FURN restored bond strengths to that of the positive control. However, only GLASS and FURN did not roughen the surface of the underlying lithium-silicate glass-ceramic.

PMID:34269542 | DOI:10.3290/j.jad.b1367933

J Adhes Dent. 2021 Jul 23;23(4):335-345. doi: 10.3290/j.jad.b1650153.

ABSTRACT

PURPOSE: The pretreatment of glass-ceramic before adhesive cementation can be performed with hydrofluoric acid (HF)/silanization (S) or with an ammonium polyfluoride-containing primer (APF). It can be modified by application of a silane-containing universal adhesive (UA) and/or additional silanization. The aim of this study was to evaluate the bond strength of composite cements to two different glass ceramics after different pretreatments and aging.

MATERIALS AND METHODS: Disks of leucite-reinforced glass-ceramic or lithium-disilicate glass-ceramic were pretreated with HF+S, HF+UA, HF+S+UA, APF, or APF+S, bonded in pairs with composite cement and sectioned into microsticks (n = 96/group). The microtensile bond strength was determined either after 24 h (n = 48) or after aging for 6 months in water (n = 48). Fracture patterns were analyzed at 50X magnification. Statistical evaluation was performed using the Kruskal-Wallis test, pairwise comparisons with Bonferroni’s correction, and the chi-squared test (p < 0.05).

RESULTS: Pretreatment with HF+UA or APF led to significantly lower bond strength compared to HF+S. Additional silanization after application of UA or APF resulted in a significant increase in bond strength. After aging, HF+UA groups showed significantly lower bond strengths, independent of additive silanization. Aging did not affect APF-pretreated leucite-reinforced glass-ceramic; for lithium-disilicate glass-ceramic, the bond strength dropped significantly. Additional silanization improved aging resistance for the respective groups.

CONCLUSION: Bond strength and its long-term stability depend on the ceramic used and on the pretreatment. An ammonium polyfluoride-containing primer seems to be a promising option compared to conventional pretreatment with hydrofluoric acid. Additive silanization improves the long-term stability of the microtensile bond strength.

PMID:34269544 | DOI:10.3290/j.jad.b1650153

Korean J Radiol. 2021 Jul 14. doi: 10.3348/kjr.2020.1462. Online ahead of print.

ABSTRACT

OBJECTIVE: To investigate the diagnostic yield of diffusion-weighted imaging (DWI) in patients with transient global amnesia (TGA) and identify significant parameters affecting diagnostic yield.

MATERIALS AND METHODS: A systematic literature search of the MEDLINE and EMBASE databases was conducted to identify studies that assessed the diagnostic yield of DWI in patients with TGA. The pooled diagnostic yield of DWI in patients with TGA was calculated using the DerSimonian-Laird random-effects model. Subgroup analyses were also performed of slice thickness, magnetic field strength, and interval between symptom onset and DWI.

RESULTS: Twenty-two original articles (1732 patients) were included. The pooled incidence of right, left, and bilateral hippocampal lesions was 37% (95% confidence interval [CI], 30-44%), 42% (95% CI, 39-46%), and 25% (95% CI, 20-30%) of all lesions, respectively. The pooled diagnostic yield of DWI in patients with TGA was 39% (95% CI, 27-52%). The Higgins I² statistic showed significant heterogeneity (I² = 95%). DWI with a slice thickness ≤ 3 mm showed a higher diagnostic yield than DWI with a slice thickness > 3 mm (pooled diagnostic yield: 63% [95% CI, 53-72%] vs. 26% [95% CI, 16-40%], p < 0.01). DWI performed at an interval between 24 and 96 hours after symptom onset showed a higher diagnostic yield (68% [95% CI, 57-78%], p < 0.01) than DWI performed within 24 hours (16% [95% CI, 7-34%]) or later than 96 hours (15% [95% CI, 8-26%]). There was no difference in the diagnostic yield between DWI performed using 3T vs. 1.5T (pooled diagnostic yield, 31% [95% CI, 25-38%] vs. 24% [95% CI, 14-37%], p = 0.31).

CONCLUSION: The pooled diagnostic yield of DWI in TGA patients was 39%. DWI obtained with a slice thickness ≤ 3 mm or an interval between symptom onset and DWI of > 24 to 96 hours could increase the diagnostic yield.

PMID:34269537 | DOI:10.3348/kjr.2020.1462

J Adhes Dent. 2021 Jul 23;23(4):309-318. doi: 10.3290/j.jad.b1650013.

ABSTRACT

PURPOSE: Thanks to adhesive techniques and strengthened glass ceramics, ultrathin bonded occlusal veneers have been recently introduced. However, since a universally accepted thickness limit for ultrathin ceramics has yet to be established, their resistance to fracture needs to be better investigated. The purpose of this in vitro study was to evaluate the effect of dentin bonding on the flexural properties (ie, fracture load and flexural strength) of a lithium-disilicate (LD) glass ceramic when used in thicknesses equal to or less than the manufacturer’s recommendations for occlusal restorations.

MATERIALS AND METHODS: A total of 96 dentin slices (2.0 mm thick and 15 mm long) were obtained by sectioning bovine teeth along their long axes. LD slices of different thicknesses (1.5 mm/1.3 mm/1.0 mm/0.8 mm/0.6 mm) and 15 mm in length were cut from CAD/CAM LD blocks (IPS e.max CAD-C16). In each of 5 experimental groups, 16 dentin slices were adhesively luted to 16 LD slices (n = 16) of the same thickness, in order to create 16 bi-layered dentin-LD bonded assemblies. In the control group, the 16 remaining dentin slices were conventionally cemented to 1.5-mm-thick LD slices (n = 16) using a resin-modified glass-ionomer cement (FujiCEM 2). All dentin-LD assemblies were cut perpendicularly to their joint interface, in order to obtain 1-mm-wide, 15-mm-long bi-layered prismatic beams, having the following final thicknesses: for the 5 experimental groups, 2 mm (dentin layer) + 1.5 mm/ 1.3 mm/1.0 mm/0.8 mm/0.6 mm (LD layer); for the control group, 2 mm (dentin layer) + 1.5 mm (LD layer). All prismatic beams were subjected to a three-point bending test (14-mm span, load applied on the LD side). Fracture loads (N) and flexural strengths (MPa) were recorded. Data were analyzed using one-way ANOVA on ranks tests (α = 0.05). The correlations between the recorded flexural strengths and the dentin:LD thickness ratio and between the flexural strength and the luting strategy were also investigated. The failure modes were observed and classified.

RESULTS: No statistically significant differences were recorded between the conventionally luted control group (LD thickness 1.5 mm; fracture load 35.26 N; flexural strength 60.44 MPa) and the thinnest adhesively luted experimental group (LD thickness 0.6 mm; fracture load 28.97 N; flexural strength 90.01 MPa) in terms of fracture load and flexural strength. A fracture involving both the dentin and the LD of the bi-layered prismatic beam, but without any debonding between the LD and the dentin substrates of the broken specimen, was the most common failure mode observed on the adhesively luted samples.

CONCLUSION: Compared to conventional cementation, when LD is bonded to dentin, the flexural properties of the whole system are improved, and the two different substrates seem to behave like a single unit. Once adhesively luted, 0.6-mm-thick LD has the same fracture load and flexural strength as that of the conventionally luted 1.5-mm-thick LD.

PMID:34269541 | DOI:10.3290/j.jad.b1650013

Clin Psychol Psychother. 2021 Jul 16. doi: 10.1002/cpp.2643. Online ahead of print.

ABSTRACT

Literature suggests that Acceptance and Commitment Therapy (ACT) is effective in improving well-being and in reducing psychopathological symptoms commonly experienced by people with chronic illness (CI). Compassion Focused Therapy (CFT) reduces psychological distress, especially in individuals with high levels of shame and self-criticism, but few studies have explored CFT in CI. Additionally, studies almost exclusively compared ACT and CFT with inactive controls (wait-list; treatment as usual). Also, there is an interest in developing cost-effective mental health solutions, such as low intensity online psychological interventions. This Randomized Controlled Trial (RCT) aimed to assess the acceptability and compare the efficacy of 4-sessions online ACT (n = 25) and CFT (n = 24) interventions in a sample of people with CI. Results showed both interventions were acceptable, with attrition rates at post-intervention comparable to those found in similar studies (around 50%). Intention To Treat analyses showed that participants presented significantly less illness-related shame, less uncompassionate self-responding, and more valued living after the intervention, although no difference was found between conditions. Results were sustained at 3-months and 6-months follow-up. Results did not find statistical differences between conditions through Reliable Change Index (RCI). Correlation between demographics and RCI showed that, at post-intervention, younger participants presented more behavioral awareness, men presented more valued action, and participants with CI for shorter periods presented less uncompassionate self-responding and less anxiety. Results suggest that low intensity (4 sessions) online ACT and CFT are cost-effective approaches to promote mental health of individuals with CI. Results and limitations are thoroughly discussed.

PMID:34269493 | DOI:10.1002/cpp.2643

Hepatol Res. 2021 Jul 16. doi: 10.1111/hepr.13698. Online ahead of print.

ABSTRACT

AIM: There are limited data from prospective studies depicting the clinical usefulness of the new criteria for the sarcopenia in liver disease produced by the Japan Society of Hepatology (JSH). Therefore, we aimed to evaluate the clinical usefulness of this new criteria for prognosis in cirrhotic patients.

METHODS: This prospective study was performed at six centers. The 300 enrolled patients, aged ≥20 years with liver cirrhosis, were evaluated over a 3-year period for skeletal muscle mass index (SMI) and grip strength. Sarcopenia was defined according to the JSH criteria by grip strength and computed tomography-based SMI values. We investigated the correlation between sarcopenia and the survival rate of cirrhotic patients.

RESULTS: Among the 300 assessed patients there were 99 (33%) patients with sarcopenia. The number of deaths in the sarcopenia and non-sarcopenia groups was 34 (34.3%) and 38 (18.9%), respectively (P = 0.002). Multivariate analysis confirmed that sarcopenia, decompensated phase, ALBI (albumin-bilirubin) Grade, and hepatocellular carcinoma (HCC) Stage 3/4 were independent factors correlated with death in patients with liver cirrhosis during the observation period. The interaction between sarcopenia and the presence of HCC was statistically significant (P < 0.001), and the presence of HCC had the highest hazard ratio of 6.665 for deaths in cirrhotic patients when non-sarcopenia and the absence of HCC were used as references.

CONCLUSIONS: The new JSH criteria for sarcopenia are accurate predictors of poor prognosis in patients with liver cirrhosis. This article is protected by copyright. All rights reserved.

PMID:34269502 | DOI:10.1111/hepr.13698

Korean J Radiol. 2021 Jul 1. doi: 10.3348/kjr.2021.0223. Online ahead of print.

ABSTRACT

The recent introduction of various high-dimensional modeling methods, such as radiomics and deep learning, has created a much greater diversity in modeling approaches for survival prediction (or, more generally, time-to-event prediction). The newness of the recent modeling approaches and unfamiliarity with the model outputs may confuse some researchers and practitioners about the evaluation of the performance of such models. Methodological literacy to critically appraise the performance evaluation of the models and, ideally, the ability to conduct such an evaluation would be needed for those who want to develop models or apply them in practice. This article intends to provide intuitive, conceptual, and practical explanations of the statistical methods for evaluating the performance of survival prediction models with minimal usage of mathematical descriptions. It covers from conventional to deep learning methods, and emphasis has been placed on recent modeling approaches. This review article includes straightforward explanations of C indices (Harrell’s C index, etc.), time-dependent receiver operating characteristic curve analysis, calibration plot, other methods for evaluating the calibration performance, and Brier score.

PMID:34269532 | DOI:10.3348/kjr.2021.0223

Transfusion. 2021 Jul;61 Suppl 1:S15-S21. doi: 10.1111/trf.16528.

ABSTRACT

BACKGROUND: Low titer O+ whole blood (LTOWB) is being increasingly used for resuscitation of hemorrhagic shock in military and civilian settings. The objective of this study was to identify the impact of prehospital LTOWB on survival for patients in shock receiving prehospital LTOWB transfusion.

STUDY DESIGN AND METHODS: A single institutional trauma registry was queried for patients undergoing prehospital transfusion between 2015 and 2019. Patients were stratified based on prehospital LTOWB transfusion (PHT) or no prehospital transfusion (NT). Outcomes measured included emergency department (ED), 6-h and hospital mortality, change in shock index (SI), and incidence of massive transfusion. Statistical analyses were performed.

RESULTS: A total of 538 patients met inclusion criteria. Patients undergoing PHT had worse shock physiology (median SI 1.25 vs. 0.95, p < .001) with greater reversal of shock upon arrival (-0.28 vs. -0.002, p < .001). In a propensity-matched group of 214 patients with prehospital shock, 58 patients underwent PHT and 156 did not. Demographics were similar between the groups. Mean improvement in SI between scene and ED was greatest for patients in the PHT group with a lower trauma bay mortality (0% vs. 7%, p = .04). No survival benefit for patients in prehospital cardiac arrest receiving LTOWB was found (p > .05).

DISCUSSION: This study demonstrated that trauma patients who received prehospital LTOWB transfusion had a greater improvement in SI and a reduction in early mortality. Patient with prehospital cardiac arrest did not have an improvement in survival. These findings support LTOWB use in the prehospital setting. Further multi-institutional prospective studies are needed.

PMID:34269467 | DOI:10.1111/trf.16528

Clin Transplant. 2021 Jul 16. doi: 10.1111/ctr.14426. Online ahead of print.

ABSTRACT

Addressing racial disparities in living donor kidney transplants (LDKT) among Black patients warrants innovative programs to improve living donation rates. The Living Organ Video Educated Donors (LOVED) program is a 2-arm, culturally-tailored, distance-based, randomized controlled feasibility trial. The group-based, 8-week program used peer-navigator led video chat sessions and web-app video education for Black kidney waitlisted patients from a United States southeastern state. Primary feasibility results for LOVED (n=24) and usual care (n=24) arms included LOVED program tolerability (i.e., 95.8% retention), program fidelity (i.e., 78.9% video education adherence and 72.1% video chat adherence). LDKT attitudinal and knowledge results favored the LOVED group where a statistically significant effect was reported over 6-months for willingness to approach strangers (estimate ± SE: -1.0 ± 0.55, F(1, 45.3) = 7.5, p = 0.009) and self-efficacy to advocate for a LDKT -0.81 ± 0.31, F(1, 45.9) = 15.2, p < 0.001. Estimates were improved but not statistically significant for willingness to approach family and friends, LDKT knowledge and concerns for living donors (all p’s >0.088). Secondary measures at 6 months showed an increase in calls for LOVED compared to usual care (p = 0.008) though no differences were found for transplant center evaluations or LDKTs. Findings imply that LOVED increased screening calls and attitudes to approach potential donors but feasibility outcomes found program materials require modification to increase adherence. NCT03599102 This article is protected by copyright. All rights reserved.

PMID:34269480 | DOI:10.1111/ctr.14426

Transfusion. 2021 Jul;61 Suppl 1:S174-S182. doi: 10.1111/trf.16498.

ABSTRACT

BACKGROUND: The Compensatory Reserve Measurement (CRM) is a novel method used to provide early assessment of shock based on arterial wave form morphology changes. We hypothesized that (1) CRM would be significantly lower in those trauma patients who received life-saving interventions compared with those not receiving interventions, and (2) CRM in patients who received interventions would recover after the intervention was performed.

STUDY DESIGN AND METHODS: We captured vital signs along with analog arterial waveform data from trauma patients meeting major activation criteria using a prospective study design. Study team members tracked interventions throughout their emergency department stay.

RESULTS: Ninety subjects met inclusion with 13 receiving a blood product and 10 a major airway intervention. Most trauma was blunt (69%) with motor vehicle collisions making up the largest proportion (37%) of injury mechanism. Patients receiving blood products had lower CRM values just prior to administration versus those who did not (50% versus 58%, p = .045), and lower systolic pressure (SBP; 95 versus 123 mmHg, p = .005), diastolic (DBP; 62 versus 79, p = .007), and mean arterial pressure (MAP; 75 versus 95, p = .006), and a higher pulse rate (HR; 101 versus 89 bpm, p = .039). Patients receiving an airway intervention had lower CRM values just prior to administration versus those who did not (48% versus 58%, p = .062); however, SBP, DBP, MAP, and HR were not statistically distinguishable (p ≥ .645).

CONCLUSIONS: Our results support our hypotheses that the CRM distinguished those patients who received blood or an airway intervention from those who did not, and increased appropriately after interventions were performed.

PMID:34269446 | DOI:10.1111/trf.16498