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Nevin Manimala Statistics

Evaluation of the effects of thermal changes on the bond strength between zirconia framework and veneering ceramic during the firing process

Eur Oral Res. 2023 May 4;57(2):108-114. doi: 10.26650/eor.2023978293.

ABSTRACT

PURPOSE: The aim of this in-vitro study was to evaluate the effect of thermal changes to shear bond strength during the firing process of veneering porcelain on a zirconia framework.

MATERIALS AND METHODS: Single yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) framework ceramic (Kavo Dental GmbH) and three different types of veneering ceramics (IPS e.max Ceram, Vita VM9, and GC Initial Zr-FS) were used. One-hundred-twenty standard disc-shaped samples were prepared from zirconia blocks by using a CAD/CAM system (Kavo Everest). Four different cooling processes (maximum, 25°C/min, 50°C/min and 75°C/min) were applied to the veneering ceramics and the shear bond strength (SBS) test was performed. Ceramic surfaces were investigated by using scanning electron microscopeic (SEM). The possible occurrence of a t-m transformation of zirconia was evaluated by X-Ray Diffraction (XRD). Two-way analysis of variance, Bonferroni correction and paired comparisons were used for statistical analysis.

RESULTS: The main effects of veneering ceramics on shear bond strength were found to be significant (p=0.042). The mean shear bond strength values differ according to the cooling process (p<0.001). The monoclinic phase ratio increased in groups with fast cooling process.

CONCLUSION: The thermal changes during the firing process of veneering porcelain on a zirconia framework influenced the shear bond strength of the all-ceramic bilayered system. A slow cooling process provided higher strength for bilayer ceramic samples.

PMID:37525861 | PMC:PMC10387139 | DOI:10.26650/eor.2023978293

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Nevin Manimala Statistics

Influence of home bleaching regimen on microhardness and flexural strength of two contemporary composite resins – an in vitro evaluation

Eur Oral Res. 2023 May 4;57(2):90-95. doi: 10.26650/eor.20231083203.

ABSTRACT

PURPOSE: This study was to compare and evaluate the effect of home bleaching on the microhardness and flexural strength of microhybrid and nanohybrid composite resins.

MATERIALS AND METHODS: The study samples were prepared using a custom-made silicon rubber mold. For microhardness evaluation, 40 disc-shaped specimens (4mm*2mm) were prepared and divided into 4 groups: GROUP A (n=10): microhybrid (GC Solaire X, GC Corporation) control group, GROUP B (n=10) nanohybrid (Tetric N Ceram, Ivoclar Vivadent) control group, GROUP C (n=10): microhybrid bleaching group, GROUP D (n=10) nanohybrid bleaching group. For flexural strength evaluation, 40 bar shaped specimens (25mm*2mm*2mm) were prepared. They were divided into 4 groups, GROUP 1 (n=10): microhybrid control group, GROUP 2 (n=10) nanohybrid control group, GROUP 3 (n=10): microhybrid bleaching group, GROUP 4(n=10) nanohybrid bleaching group. All the control groups were placed in artificial saliva and bleaching groups were exposed to home bleaching agent for 14 days according to manufacturer’s instructions. The microhardness and flexural strength were evaluated for the respective specimens after 14 days and the data were statistically analyzed.

RESULTS: Home bleaching regimen decreased microhardness of both microhybrid and nanohybrid composites whereas there was no significant effect on the flexural strength. Nanohybrid composites showed greater microhardness values before and after bleaching.

CONCLUSION: Bleaching agents, irrespective of their concentration can decrease the microhardness of the composite resin samples, which raises a concern about replacement of these restorations due to the effects on physical and mechanical properties.

PMID:37525860 | PMC:PMC10387141 | DOI:10.26650/eor.20231083203

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Nevin Manimala Statistics

Comparison of the shear bond strength of new and recycled metallic brackets using different adhesive materials : an in vitro study

Eur Oral Res. 2023 May 4;57(2):96-102. doi: 10.26650/eor.20231163180.

ABSTRACT

PURPOSE: To evaluate and compare shear bond strength (SBS) of new and recycled metallic brackets bonded to conditioned and reconditioned enamel, using two different adhesive materials.

MATERIALS AND METHODS: 72 extracted sound human premolars were randomly divided into 6 groups. Transbond XT light cured composite (LCC) and Fuji Ortho LC resin-modified glass ionomer (RMGI), were used as adhesive materials. In groups 1 and 2 (control), new brackets were bonded to sound premolars using either LCC or RMGI, respectively. In Groups 3 and 4, new brackets were bonded to reconditioned enamel; and in groups 5 and 6, sandblasted recycled brackets were rebonded to reconditioned enamel. After 5.000 thermal cycles between 5ºC and 55ºC, SBS was evaluated and adhesive remnant on the enamel assessed using the ARI index. Statistical analyses included Shapiro-Wilk, ANOVA, Fligner-Killeen ANOVA and Tukey tests.

RESULTS: The statistical analysis showed no significant difference in SBS comparing control and experimental groups for either new or recycled brackets (p = 0.848). The SBS was significantly higher in brackets bonded with LCC (15.7 MPa) than RMGI (11.6 MPa) (p = 0.006). Adhesive failure was the most frequent, with the adhesive remnant covering more than 50% of the bracket base.

CONCLUSION: No significant differences were observed in SBS using either new or recycled brackets, regardless of the dental surface treatment (conditioned or reconditioned). Significantly higher SBS values were obtained with LCC adhesive. Adhesive failure prevails in all groups.

PMID:37525859 | PMC:PMC10387137 | DOI:10.26650/eor.20231163180

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Nevin Manimala Statistics

Does hot coffee or cold coffee cause more discoloration on resin based composite materials?

Eur Oral Res. 2023 May 4;57(2):103-107. doi: 10.26650/eor.20231152488.

ABSTRACT

PURPOSE: This study aimed to examine the effect of beverages at different temperatures on the coloring of composites.

MATERIALS AND METHODS: A total of 48 cylindrical samples, 24 of which were prepared from 2 composite materials (G’aenial; Estelite Σ Quick), were included in the study. The sample dimensions were standardized at 2 x 10 mm2. After the polishing, the initial color measurements were performed using a spectrophotometer. The samples were divided into 3 subgroups as distilled water, hot coffee (60 °C) and cold coffee (0 °C) (n=8). During the 7th and 30th days, the samples were immersed in the solutions for 15 min every day. Color measurements were repeated on the 7th and 30th days. Data were analyzed using a two-way analysis of variance, followed by the Tukey post-hoc test (p<0.05).

RESULTS: The highest color change was detected on the 7th and 30th days in the G-aenial anterior microhybrid composite immersed in hot coffee (p<0.001). The application of hot and cold coffee applications did not make a statistically significant difference in the coloration of the Estelite Σ Quick composite samples at the end of the 7th (p=0.346) and 30th (p=910) days.

CONCLUSION: Hot drinks had a more coloring effect on restorations. This coloration was quite evident in the microhybrid composite.

PMID:37525856 | PMC:PMC10387140 | DOI:10.26650/eor.20231152488

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Nevin Manimala Statistics

The effects of sports participation on the dental age in adolescents

Eur Oral Res. 2023 May 4;57(2):75-82. doi: 10.26650/eor.20231134537.

ABSTRACT

PURPOSE: The present study aims to assess the effect of sports on the dental maturity using two different dental age assessment methods and to determine whether there is a significant correlation between dental maturity and body mass index.

MATERIALS AND METHODS: One hundred and thirty-eight students from Sports High School (study group) and 126 from Fine Arts High School (control group) with standard panoramic radiographs were included in the study. Dental age was assessed using Nolla’s and Haavikko’s methods. Demographic information regarding the weekly training hours and sports age of the study group participants was gathered. Body mass index values of all participants were calculated. Factorial analysis of variance and Tukey’s test were performed and the Pearson correlation coefficient was calculated.

RESULTS: The mean age of the students was 15.93 ± 1.13 years for the study group and 15.99 ± 1.09 years for the control group. Mean dental age values were lower than the mean chronological age values in both high schools. The difference between the dental and chronological ages was insignificant in Sports High School (p > 0.05). Differences in the body mass index between high schools and genders were statistically significant (p<0.05). Significant correlations were detected between the sports and dental ages and between dental age and body mass index values.

CONCLUSION: Sports participation could have positive effects on the dental maturity as well as on the bone development.

PMID:37525854 | PMC:PMC10387144 | DOI:10.26650/eor.20231134537

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Effects of Androgens on the Thickness of Retinal Layers in Transgender Men and in Women with Polycystic Ovarian Syndrome

Transgend Health. 2023 Jul 28;8(4):363-370. doi: 10.1089/trgh.2022.0061. eCollection 2023 Aug.

ABSTRACT

PURPOSE: This study aimed to evaluate the relationship between androgens and the retinal thickness by comparing the macular thickness (MT), retinal nerve fiber layer (RNFL), and ganglion cell complex (GCC) thickness of female-to-male transgender men (TGM), women with polycystic ovary syndrome (PCOS), and cisgender women (CW).

METHODS: Thirty-four eyes of 34 TGM, 34 eyes of 34 women with PCOS, and 45 eyes of 45 CW were evaluated by optical coherence tomography. One-way analysis of variance and body mass index (BMI)-adjusted one-way analysis of covariance were conducted to test the differences between groups for statistical evaluation.

RESULTS: The parafoveal MT in TGM was significantly higher than women with PCOS and CW (p<0.001 and p=0.022, respectively). After adjusting for BMI, the perifoveal MT in TGM was significantly higher than women with PCOS and CW (p=0.041 and p=0.021, respectively). The nasal RNFL thickness in TGM was significantly higher than women with PCOS and CW (p=0.021 and p=0.009, respectively). The means of average and inferior RNFL, fovea, and the mean of all GCC values were higher in the TGM group than women with PCOS and CW, but these results were not statistically significant.

CONCLUSIONS: In this study, there was a significant difference between the TGM group and the CW group for the thickness of the nasal RNFL and parafoveal and perifoveal macular area. Androgens may have the potential to increase retinal thickness in TGM; however, there is a need for validation in larger study groups. Clinical Trial Registration Number: HNEAH-KAEK 2021/4.

PMID:37525838 | PMC:PMC10387147 | DOI:10.1089/trgh.2022.0061

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Nevin Manimala Statistics

Gender-Affirming Voice Modification for Transgender Women: Characteristics and Outcomes

Transgend Health. 2023 Jul 28;8(4):352-362. doi: 10.1089/trgh.2021.0071. eCollection 2023 Aug.

ABSTRACT

OBJECTIVE: The primary aim of this study was to define characteristics of transgender women seeking gender-affirming voice modification at our voice center. The secondary aim was to evaluate outcome measures, comparing (a) behavioral voice training alone, (b) surgery alone, and (c) combination of behavioral voice training+surgery.

METHODS: Patients seen in a 30-month period, who sought care for gender-affirming voice modification, were included if they were assigned male at birth and identified as female. Patient demographic information, patient quality of life index scores, Trans Woman Voice Questionnaire (TWVQ), and acoustic data were collected before and after intervention.

RESULTS: Sixteen patients met inclusion criteria. The majority of patients were (a) undergoing hormone replacement therapy at initiation of treatment, (b) were presenting in public for over 2 years as female, and (c) had a history of psychological disorders (i.e., gender dysphoria, anxiety, depression, and attention deficit hyperactivity disorder [ADHD]). Increased f0 and decreased TWVQ scores were evident and statistically significant within behavioral voice training cohort and behavioral voice training+surgery cohort. Treatment groups appear similar with respect to average changes; pre- and post-data were not available for surgery only patients. Greater change in f0 was directly correlated with increased number of voice training sessions.

CONCLUSION: There is variability in treatment course for patients seeking gender-affirming voice modification; however, treatment type may not impact outcomes. Increased patient quality of life and increased speaking fundamental frequency were found in this patient cohort.

PMID:37525833 | PMC:PMC10387149 | DOI:10.1089/trgh.2021.0071

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Genetic Variations of AKT1 are Associated with Risk Screening for Non-Alcoholic Fatty Liver Disease

Risk Manag Healthc Policy. 2023 Jul 26;16:1365-1376. doi: 10.2147/RMHP.S416592. eCollection 2023.

ABSTRACT

PURPOSE: Protein kinase B (PKB/AKT) has shown a high profile in the research of metabolic diseases. This research sought to determine whether the AKT1 gene’s single nucleotide polymorphisms (SNPs) and the risk of developing non-alcoholic fatty liver disease (NAFLD) were related.

PATIENTS AND METHODS: Recruited in this case-control study were 2693 subjects, including 815 with NAFLD and 1878 without NAFLD. Three SNPs of AKT1 (rs2494732, rs2494752 and rs1130233) were genotyped. To examine the correlation between SNPs and NAFLD susceptibility, logistic regression was performed.

RESULTS: After adjusting for sex, age, triglyceride and glucose, AKT1 rs2494732-C (all P < 0.05 in co-dominant model, dominant model and additive model) and rs2494752-G (P < 0.05 in co-dominant model) were linked to a lower risk of NAFLD. The combined effect of both SNPs on NAFLD risk was statistically significant, showing a dose dependence (Ptrend = 0.010). Sex, body mass index, hypertension, hyperglycemia, hypertriglyceridemia, high-density lipoprotein-cholesterol, alanine aminotransferase, and beneficial alleles were all significant predictors of NAFLD risk (all P < 0.05). The prediction model achieved good discrimination, with an area under the receiver operating characteristic curve of 0.779. The Hosmer-Lemeshow test suggested an inadequate calibration of the model (χ2 = 21.073, P = 0.007).

CONCLUSION: AKT1 rs2494732 and rs2494752 may be related to Chinese NAFLD susceptibility. The prediction model combining both SNPs with clinical factors displays a strong ability to discriminate NAFLD patients. Both SNPs may be exploited to design new models for early screening of NAFLD high-risk population.

PMID:37525829 | PMC:PMC10387243 | DOI:10.2147/RMHP.S416592

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Nevin Manimala Statistics

Incidence and outcome of perforations during medium vessel occlusion compared with large vessel occlusion thrombectomy

J Neurointerv Surg. 2023 Jul 31:jnis-2023-020531. doi: 10.1136/jnis-2023-020531. Online ahead of print.

ABSTRACT

BACKGROUND: Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation.

METHODS: In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0-2) and all-cause mortality at 90 days. Binomial test, chi-squared test and t-test for unpaired samples were used for statistical analysis.

RESULTS: During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%, p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%, p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation.

CONCLUSIONS: In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

PMID:37524518 | DOI:10.1136/jnis-2023-020531

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Immediately loaded full arch implant rehabilitation and oral health-related quality of life: A retrospective cohort study from primary dental care

Clin Implant Dent Relat Res. 2023 Jul 31. doi: 10.1111/cid.13254. Online ahead of print.

ABSTRACT

AIMS: This study evaluates patient-centered outcomes in patients undergoing full-arch rehabilitation, with immediate loading of implants. Using the Oral Health Impact Profile questionnaire pre-and post-treatment, it assesses the hypothesis that immediate full arch loading significantly improves quality of life.

METHODOLOGY: A dataset was defined as: 20 consecutive patients from a research database who had undergone IFAL surgery (maxilla, mandible, or both) and definitive restoration by a single clinician, and completed the OHIP-14 questionnaire prior to treatment and after restoration.

RESULTS: Pre (T0 ) and post (T1 ) treatment questionnaires were analyzed from 20 consecutive patients in whom a total of 160 implants were placed. The mean T0 score was 26.7, and mean T1 score 4.6. Differences were statistically significant (p = 0.00008). Greatest improvements were seen in psychological discomfort and disability, and pain. Worsening quality of life was shown by questions relating to speech in six patients and taste in three patients.

CONCLUSION: This study demonstrates that overall IFAL significantly improves tooth-related quality of life. It suggests reasons for patients to seek treatment while providing evidence to manage expectations, such as possible implications on speech, thus supporting informed consent of future patients in a primary care setting.

PMID:37524507 | DOI:10.1111/cid.13254