Candida albicans is the main causative pathogen of denture stomatitis, which affects many complete denture patients. Objective: To evaluate the effect of different concentrations of nanodiamonds (NDs) added to polymethyl methacrylate (PMMA) denture base material on Candida albicans adhesion as well as on surface roughness and contact angle. Methodology: Acrylic resin specimens sized 10×10×3 mm3 were prepared and divided into four groups (n=30) according to ND concentration (0%, 0.5%, 1%, 1.5% by wt). Surface roughness was measured with a profilometer, and the contact angle with a goniometer. The effect of NDs on Candida albicans adhesion was evaluated using two methods: 1) slide count and 2) direct culture test. Analysis of variance (ANOVA) and Tukey's post hoc test were used in the statistical analyses. Results: Addition of NDs decreased the Candida albicans count significantly more than in the control group (p<0.05), with a lowest of 1% NDs. Addition of NDs also significantly decreased the surface roughness (p<0.05), but the contact angle remained the same. Incorporation of NDs into the PMMA denture base material effectively reduced Candida albicans adhesion and decreased surface roughness. Conclusion: PMMA/NDs composites could be valuable in the prevention of denture stomatitis, which is considered one of the most common clinical problems among removable denture wearers.

Purpose To compare the accuracy of intraoral and extraoral scanners (IOSs and EOSs) with different scanning technologies. Material and Methods A phantom cast was used to simulate the patient's mouth. Polyether impression was made of the phantom cast and poured to fabricate stone casts. The stone casts were scanned by two IOSs (3shape Trios 3, 3S and Dental Wings, DW) and two EOSs (S600 Arti Zirkonzahn, ZK and Ceramill map 600 Amann Girrbach, AG) to obtain digital casts. Reference teeth (canines, premolar, and molars) dimensions were measured on the digital casts by Geomagic software and compared to measurements of the stone cast done by stereomicroscope. The dimensions were occluso‐cervical mesio‐distal, and bucco‐lingual and their average was calculated. Differences between digital and stereoscopic measurements were assessed using paired t‐test. Discrepancies between these measurements were calculated as differences and were compared among the four scanners using ANOVA. Results The differences among the discrepancies of the four scanners were not significant overall (p = 0.969), in premolars (p = 0.932) or molars (p = 0.069) but significant in canines (p = 0.025). The discrepancies of the EOSs were ≤0.01 mm in canines and molars. DW had the greatest discrepancy in canines and molars. Conclusions The IOSs and EOSs had similar accuracy except in canines where EOSs performed better. The accuracy of scanning is affected by the smoothness and regularity of the teeth surfaces as in case of the canine.

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The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living with and without HIV in Nigeria. This was a cross-sectional study that recruited a convenience sample of 4471 (20.5% HIV positive) adults in Nigeria. Binary logistic regression analysis was conducted to test the associations between the explanatory variable (HIV positive and non-positive status) and the outcome variables-COVID-19 related behavior changes (physical distancing, isolation/quarantine, working remotely) and food insecurity (hungry but did not eat, cut the size of meals/skip meals) controlling for age, sex at birth, COVID-19 status, and medical status of respondents. Significantly fewer people living with HIV (PLWH) reported a positive COVID-19 test result; and had lower odds of practicing COVID-19 risk preventive behaviors. In comparison with those living without HIV, PLWH had higher odds of cutting meal sizes as a food security measure (AOR: 3.18; 95% CI 2.60-3.88) and lower odds of being hungry and not eating (AOR: 0.24; 95% CI 0.20-0.30). In conclusion, associations between HIV status, COVID-19 preventive behaviors and food security are highly complex and warrant further in-depth to unravel the incongruities identified.

Purpose To compare the accuracy of 3D printed and digital casts produced from various intraoral and extraoral scanners with different scanning technologies. Materials and Methods A conventional stone cast was fabricated from the reference typodont cast and scanned with two intraoral scanners (TRIOS 3 version 1.4.7.5, and Dental Wings version 2.1.0.421), and two extraoral scanners (S600 Arti, Zirkonzahn, and Ceramill map 600, Amann Girrbach GmbH). All digital scans were saved in the form of STL files and measurements were calculated using Geomagic analysis software. Two types of measurements were assessed on the casts: tooth‐ and arch‐level measurements. Absolute errors were calculated by subtracting the measurements on 3D printed, digital, and conventional stone casts from the measurements on the reference typodont cast. One‐way ANOVA was used for comparing different measurement errors between groups. Linear regression was performed to determine the association between different explanatory variables, and the average measurement errors (dependent variable) adjusted to reference cast measurements. Regression coefficients (B) and 95% confidence intervals (CI) were calculated. Results For both 3D printed and digital casts, Dental Wings showed significantly greater error compared to other scanners and to the conventional stone cast at all measurements except arch lengths (in the 3D printed modality only), while conventional casts showed the lowest error. Error was significantly higher in intraoral than extraoral scanners (B = 0.009, 95% CI = 0.005, 0.02), and in arch level measurements than tooth level measurements (B = 0.03, 95% CI = 0.01, 0.04), and significantly lower in 3D printed than digital casts (B = –0.04, 95% CI = –0.05, –0.04). There were no statistically significant differences between measurement errors of both arches (maxillary and mandibular arches). Conclusions Extraoral scanners showed higher accuracy than intraoral scanners, and 3D printed casts showed higher accuracy than their digital counterparts. Dental Wings scanner had the greatest measurement error.

An online survey was conducted to identify factors associated with financial insecurity, food insecurity and poor quality of daily lives of adults in Nigeria during the first wave of the COVID-19 pandemic. The associations between the outcome (experience of financial loss, changes in food intake and impact of the pandemic on daily lives) and the explanatory (age, sex, education level, anxiety, depression, HIV status) variables were determined using logistic regression analysis. Of the 4439 respondents, 2487 (56.0%) were financially insecure, 907 (20.4%) decreased food intake and 4029 (90.8%) had their daily life negatively impacted. Males (AOR:0.84), people who felt depressed (AOR:0.62) and people living with HIV -PLHIV- (AOR:0.70) had significantly lower odds of financial insecurity. Older respondents (AOR:1.01) had significantly higher odds of financial insecurity. Those depressed (AOR:0.62) and PLHIV (AOR:0.55) had significantly lower odds of reporting decreased food intake. Respondents who felt anxious (AOR:0.07), depressed (AOR: 0.48) and who were PLHIV (AOR:0.68) had significantly lower odds of reporting a negative impact of the pandemic on their daily lives. We concluded the study findings may reflect a complex relationship between financial insecurity, food insecurity, poor quality of life, mental health, and socioeconomic status of adults living in Nigeria during the COVID-19 pandemic.

This study assessed the influence of CAD/CAM milling and 3D-printing fabrication methods on mechanical properties of 3-unit interim fixed dental prosthesis (IFDPs) after thermo-mechanical aging. Forty 3-unit IFDPs were fabricated on a mandibular right second premolar and second molar of a typodont cast. Samples were fabricated from the following materials; auto-polymerized polymethyl methacrylate (conventional resin), CAD/CAM PMMA (milled resin) and two different CAD/CAM 3D-printed composite resins; digital light processing Asiga (DLP AS) and stereolithography NextDent (SLA ND). Mechanical properties were compared between the studied materials using Kruskal–Wallis test, followed by multiple pairwise comparisons using Bonferroni adjusted significance. There was a significant difference in flexural strength and microhardness between the studied materials (p < 0.001), with the highest mean ± SD reported in the milled IFDPs (174.42 ± 3.39, 27.13 ± 0.52), and the lowest in the conventional IFDPs (98.02 ± 6.1, 15.77 ± 0.32). Flexural strengths differed significantly between the conventional IFDPs and all materials except DLP AS. The highest elastic modulus was recorded in the milled group, and the lowest in the SLA ND group (p = 0.02). In conclusion, superior flexural strength, elastic modulus, and hardness were reported for milled IFDPs. SLA ND printed IFDPs showed comparable mechanical properties to milled ones except for the elastic modulus.

Background Dental appearance affects facial beauty, social interaction and psychological well-being particularly among adolescents. The aim of the current study was to determine factors affecting adolescent dental self-confidence and satisfaction with dental appearance in Saudi Arabia. Methods A cross-sectional study was conducted in the Eastern Province of Saudi Arabia among 3500 students attending intermediate and high schools. Data was collected from 2637 students using the translated Arabic version of the psychosocial impact of dental esthetics questionnaire (PIDAQ) in addition to questions about smile esthetics satisfaction and demographic variables including; gender, age, school grade, and parental level of education. Statistical analysis was performed by using logistic regression to assess the effect of demographical variables on PIDAQ and its domains at 5% significance level. Results About 80% of the participants were satisfied or somewhat satisfied with their smiles. Tooth alignment and tooth color were the most cited reasons for adolescents’ dissatisfaction about their smile, 34% and 33% respectively. Females and participants’ fathers’ university education figured in a statistically significant way regarding higher PIDAQ and aesthetic concerns. Females were 70%, and those with fathers’ university education were 22% more likely to have a negative psychological impact. Females expressed aesthetic concerns nearly two times more than males. Participants whose fathers possessed university education had an aesthetic concern 1.25 times more compared to those whose fathers had no school or limited school education. Females and those with mothers who had university education were less likely to have positive dental self-confidence. Conclusions Most adolescents exhibited satisfaction with their own smiles. Smile dissatisfaction in the remaining participants was related to teeth alignment, color and shape. Females were more concerned with dental esthetics and smile satisfaction than males. Females and participants whose fathers had a university education exhibited higher psychosocial impact than males and those with or without school education. However, males showed greater self-confidence in their dental aesthetics.