Influence of Chairside Simulated Adjustment (Finishing and Polishing) Protocol and Chlorhexidine Mouthwash Immersion on Color Stability and Translucency of 2 and 3 Preshaded Multilayered Monolithic Zirconia.

BACKGROUND Preshaded monolithic zirconia (MLZ) is reported to have high translucency. This study aimed to assess the effect of chlorhexidine gluconate (ChG) mouthwash on color and translucency parameter (TP) of 2 different preshaded MLZ dental ceramics after clinical adjustment. MATERIAL AND METHODS Two MLZ disk-shaped specimens [NPM (Nacera Pearl Multi-Shade) (n=72) and CZM (Ceramill Zolid FX Multilayer)] (n=72) were simulated for clinical adjustment, finished, and polished using 2 adjustment kits [recommended kit, third-party kit: Diasynt Plus and SUN (n=12 each)] and later immersed in ChG mouthwash (Avohex) for 2 weeks. Difference in color (ΔE) and TP (Y) were calculated using the CIELab formula after measuring the coordinates (Lab) with a colorimeter. Individual changes in color and TP were assessed on the Clinical acceptance (perceptible) threshold (CAT/CPT) and Translucency perception threshold (TPT), respectively. Differences between the 2 ceramics were assessed using one-way ANOVA and post hoc tests, with all differences considered significant at P<0.05. RESULTS NPM and CZM differed in color at baseline despite having the same Vita shade combination. Between the 2 preshaded MLZ ceramics, NPM showed significant changes in color when adjusted with a third-party kit. Chlorhexidine produced changes in color and TP that were designated as clinically perceptible (ΔE=1.0 to 3.3) on the CAT/CPT and TPT scales, irrespective of the adjustment kit used. ChG produced the least or no changes in glazed MLZ specimens. CONCLUSIONS ChG mouthwash, whenever prescribed for preshaded MLZ restoration, should be adjusted prior to final glazing to avoid clinical adjustments that adversely affects color and translucency of the restoration.

Evaluation of the Effects of Digital Manufacturing, Preparation Taper, Cement Type, and Aging on the Color Stability of Anterior Provisional Crowns Using Colorimetry.

BACKGROUND Replicating the 3-dimensional (3D) color of natural teeth in artificial substitutes is challenging. Fixed dental prosthodontics require aesthetic, color-stable provisional restorations. Recent milling and 3D printing digital manufacturing techniques offer improved outcomes. This study assesses color stability in various digital manufacturing methods, tapers, and aging effects on anterior provisional resin restorations. MATERIAL AND METHODS Two all-ceramic tooth preparations on typodont teeth with 10° and 20° tapers were converted into experimental dies. Forty temporary crowns were manufactured using 3D printing and computer-aided design/computer-aided manufacturing (milling). Within these 2 groups, 10 crowns were cemented using a regular and clear provisional cement. All samples were thermocycled to simulate clinical use of 6 months. Color difference formula (CIEDE2000) indicated changes between before and after cementation (ΔE00) and between after cementation and after thermocycling (ΔE00[II]). The color change was considered significant in terms of clinically perceptible (ΔE00 ≤0.62) and acceptable (ΔE00 ≤2.62) changes. One-way ANOVA (P value of less than 0.05) calculated overall differences, which were established using a Fisher post hoc test. RESULTS Crowns cemented with clear cement showed fewer color changes irrespective of the manufacturing technique or taper. Notably, only the 10° 3D-printed crown with clear cement had an imperceptible color change at the pre-/post-cementation phase. Meanwhile, the 10° and 20° milled crowns with regular cement exhibited unacceptable color changes after thermocycling. CONCLUSIONS For long­term temporization in the aesthetic zone, properly optimized 3D-printed provisional restorations cemented with clear cement had better color stability.

Comparative Evaluation of Dimensional and Occlusal Accuracy of Non-Working Antagonist Casts: A Study on Different Impression Materials and 3D Printing.

BACKGROUND The aim of this study was to assess and compare the vertical/horizontal dimensions and occlusal accuracy of non-working/opposing casts obtained from three different impression materials and 3D print cast. MATERIAL AND METHODS Dentulous Master models simulating a case of a fixed dental prosthesis were mounted on an articulator (control group). Opposing mandibular casts obtained from three different impression materialsand 3-dimensional print constituted test groups , ,and , respectively. Three points, anterior vertical (AV), posterior vertical (PV), and anteroposterior (AP) were compared for dimensional accuracy among casts. Occlusal accuracy was analyzed on Medit Link software at 3 teeth (#13, #17, and #27). After calculating means for each group, the differences were calculated at probability value of P≤0.05 using the single-sample t test, ANOVA, and Tukey test. RESULTS The dimensions were significantly different from those of the mounted master models except in Gp AL(E) and Gp AL(F) at AV dimension and Gp AL(E) at AP dimension (P>0.05). A statistically significant difference of the error of means among the 4 tested groupswere detected only at 2 dimensions (AV and PV) between the Gp AL(E) and Gp 3D-C and between Gp AL(F) and Gp 3D-C groups. Other groups showed no significant differences. CONCLUSIONS The opposing casts obtained from the extended-pour alginate and alginate alternative impression materials showed higher occlusal accuracy compared to conventional alginate and 3D printed casts.

Medical Students' Perception Regarding the Re-emerging Monkeypox Virus: An Institution-Based Cross-Sectional Study From Saudi Arabia.

INTRODUCTION:  The recent multi-nation outbreaks of human monkeypox in non-endemic areas have created an emerging public health issue. Medical students who will become future healthcare providers are directly associated with community people and can easily sensitize the general population, so it is crucial to assess their degree of knowledge and attitudes regarding recently emerging infections or pathogens. However, studies on medical students' perception of the monkeypox virus are scarce in Saudi Arabia. Therefore, the objective of this study was to assess the monkeypox virus-related knowledge and attitudes among medical students in the country. METHODS: A cross-sectional study was conducted from May to July 2022 among undergraduate medical students at King Khalid University, Abha, Saudi Arabia. A systematic random sampling technique was applied to select the study participants. A self-administered questionnaire was used to gather data on sociodemographic characteristics, knowledge and attitudes toward the monkeypox virus. Descriptive statistics and Chi-square tests were performed. RESULTS: A total of 314 medical students were recruited for this study. The findings from this study showed that the vast majority of medical students (72%) had poor knowledge about the monkeypox virus. Respondents' age, grade point average (GPA), fathers' education level, and training received about the monkeypox virus were significantly associated with the level of knowledge about the monkeypox virus (p < 0.05). Nearly half of the respondents (45.9%) agreed that the monkeypox virus could be transmitted to Saudi Arabia. Overall, this study showed that the awareness levels regarding the monkeypox virus were significantly higher among seniors as compared to junior students. CONCLUSION: The study found poor knowledge of the monkeypox virus among currently enrolled medical students in the country's highest-ranked medical school. This finding emphasizes the urgent need to increase their knowledge because controlling outbreaks requires significant cooperation from knowledgeable and skilled healthcare providers.

The Effect of Bariatric Surgery on the Relation Between Retinol-Binding Protein 4 (RBP4) and Vitamin D Plasma Levels in Male Obese Population.

Objectives Obesity is viewed as a risk factor for several life-threatening diseases. Bariatric surgeries are regarded as a safe and effective way of treating morbid obesity and are associated with alterations in molecules such as Vitamin D and retinol-binding protein 4 (RBP4). The aim of this study was to examine an association between Vitamin D and RBP4 in healthy obese individuals undergoing gastric sleeve surgery. Methods In this observational retrospective cohort study, we used clinical and biochemical profiles of morbidly obese healthy male subjects (BMI > 38.3) who underwent laparoscopic sleeve gastrectomy. RBP4 levels were evaluated by ELISA before and 6-12 months after surgery. Data were analysed using SPSS 23 statistical software. Results RBP4/Vitamin D ratio was reduced significantly after surgery (p < 0.001), however, there was no correlation between Vitamin D and RBP4 (p = 0.353). BMI was reduced significantly after surgery (p < 0.001) but was not correlated with RBP4 or Vitamin D levels before and after surgery (p > 0.05). A significant increase in the levels of calcium post-surgery was observed (p< 0.001). Conclusions In conclusion, plasma levels of Vitamin D were not correlated with RBP4 before or after laparoscopic gastric sleeve surgery.

Willingness and Self-Perceived Competence of Final-Year Medical Students to Work as Part of the Healthcare Workforce During the COVID-19 Pandemic.

PURPOSE: The coronavirus disease 2019 (COVID-19) pandemic may increase demand for healthcare professionals (HCPs), either because of a HCP shortage due to illness or because of the need to increase surge capacity. Final-year medical students are one of the resources potentially available to expand the workforce. There is a need to explore the willingness of final-year medical students to meet this demand, examine their perceived competence, and determine how their overall perceived competence correlates with their willingness. METHODS: A cross-sectional study using a self-administered electronic questionnaire was used. The questionnaire included demographic data, students' self-perceived competence derived from the patient care theme of the Saudi Medical Education Directives (SaudiMED) framework, and their willingness to be measured on a 5-point Likert scale. The study targeted final-year medical students at King Saud University, Riyadh, Saudi Arabia. RESULTS: The number of participants was 134 (56.1% response rate), of whom 47 students (34.3%) were willing to work, while 31 (23.1%) were somewhat willing. The mean total self-perceived-competence score was 58.36/88 (66.3%). Demonstration of essential clinical skills had the highest mean score 11.48/16 (71.8%) among learning outcomes. There was a positive moderate correlation between willingness and mean perceived-competence score (Spearman correlation coefficient=0.45, p<0.001). CONCLUSION: Fifty-seven percent of medical students were willing to work as part of the healthcare workforce during the COVID-19 pandemic. Better overall self-perceived competence appeared to correlate with more willingness. Students perceive themselves to be more competent in essential clinical skills. Appropriate training and supervision are suggested in all tasks assigned to them, with additional care required in areas with a lower perceived competence, such as prescription writing and essential clinical procedures.

Oral Health Status and Oral Health-related Quality of Life among Hospitalized and Nonhospitalized Geriatric Patients.

INTRODUCTION: The purpose of this study was to compare the oral health status and its effect on the oral health-related quality of life (OHRQoL) of hospitalized and nonhospitalized elderly patients in a single community. The null hypothesis for the study states that there is no difference in the oral health status and OHRQoL between hospitalized and nonhospitalized elderly patients. MATERIALS AND METHODS: This study was conducted at the King Khalid Hospital and College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia. A total of 99 (43 - hospitalized and 56 - nonhospitalized) geriatric patients participated in this study. Oral health-related quality of life was estimated using the geriatric oral health assessment index questionnaire. Decayed, missing, and filled teeth (DMFT) index and plaque index were used to assess the oral health status of the study participants. RESULTS: The mean age of the study participants was 68.2 years; 17.2% were females and 82.8% were males. There was no significant difference between hospitalized and nonhospitalized patients in OHRQoL and DMFT index. However, the oral hygiene status was better among nonhospitalized patients as compared with hospitalized patients. CONCLUSION: There was a significant difference in the oral hygiene status between hospitalized and nonhospitalized geriatric patients. CLINICAL SIGNIFICANCE: Caregivers must be sensitized to the importance of oral health for the elderly population, and oral health should be considered an integral component of general health.