Aluminum zirconate nanoparticles in etch and rinse adhesive to caries affected dentine: An in-vitro scanning electron microscopy, elemental distribution, antibacterial, degree of conversion and micro-tensile bond strength assessment.

To incorporate different concentrations of Al2O9Zr3 (1%, 5%, and 10%) nanoparticles (NP) into the ER adhesive and subsequently assess the impact of this addition on the degree of conversion, µTBS, and antimicrobial efficacy. The current research involved a wide-ranging examination that merged various investigative techniques, including the application of scanning electron microscopy (SEM) for surface characterization of NP coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, µTBS testing, and microbial analysis. Teeth were divided into four groups based on the application of modified and unmodified three-step ER adhesive primer. Group 1 (0% Al2O9Zr3 NPs) Control, Group 2 (1% Al2O9Zr3 NPs), Group 3 (5% Al2O9Zr3 NPs), and Group 4 (10% Al2O9Zr3 NPs). EDX analysis of Al2O9Zr3 NPs was performed showing elemental distribution in synthesized NPs. Zirconium (Zr), Aluminum (Al), and Oxides (O2). After primer application, an assessment of the survival rate of Streptococcus mutans was completed. The FTIR spectra were analyzed to observe the characteristic peaks indicating the conversion of double bonds, both before and after the curing process, for the adhesive Etch and rinse containing 1,5,10 wt% Al2O9Zr3 NPs. µTBS and failure mode assessment were performed using a Universal Testing Machine (UTM) and stereomicroscope respectively. The µTBS and S.mutans survival rates comparison among different groups was performed using one-way ANOVA and Tukey post hoc (p = .05). Group 4 (10 wt% Al2O9Zr3 NPs + ER adhesive) specimens exhibited the minimum survival of S.mutans (0.11 ± 0.02 CFU/mL). Nonetheless, Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) displayed the maximum surviving S.mutans (0.52 ± 0.08 CFU/mL). Moreover, Group 2 (1 wt% Al2O9Zr3 NPs + ER adhesive) (21.22 ± 0.73 MPa) samples displayed highest µTBS. However, the bond strength was weakest in Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) (14.13 ± 0.32 MPa) study samples. The etch-and-rinse adhesive exhibited enhanced antibacterial activity and micro-tensile bond strength (µTBS) when 1% Al2O9Zr3 NPs was incorporated, as opposed to the control group. Nevertheless, the incorporation of Al2O9Zr3 NPs led to a decrease in DC. RESEARCH HIGHLIGHTS: 10 wt% Al2O9Zr3 NPs + ER adhesive specimens exhibited the minimum survival of S.mutans. 1 wt% Al2O9Zr3 NPs + ER adhesive samples displayed the most strong composite/CAD bond. The highest DC was observed in Group 1: 0 wt% Al2O9Zr3 NPs + ER adhesive.

Incorporation of Zirconium Oxide Nanoparticles in Adhesive Resin for Bonding of Brackets to Enamel Conditioned with Er,Cr:YSGG, Photodynamic Therapy, and Phosphoric Acid.

Objective: To evaluate the effect of enamel conditioning methods, that is, total-etch and rinse (TER), Er,Cr:YSGG (ECYL), and photodynamic therapy (PDT) on the shear bond strength (SBS) of orthodontic metallic brackets bonded using Zirconium oxide experimental adhesive (ZOEA). Methods: Sixty human incisor buccal surfaces were cleaned and allocated into three groups based on the method of enamel surface treatment, that is, TER using 37% phosphoric acid gel, methylene blue photosensitizer activated by PDT and ECYL (n = 20 each). Each group was further divided into two subgroups (n = 10) based on the type of adhesive, that is, ZOEA and experimental adhesive (EA). Metallic brackets were seated using composite resin. Samples were placed in a universal testing machine for SBS and failure mode using the ARI index. One-way analysis of variance and post hoc Tukey were used for multiple comparisons. ARI was presented in percentages in different investigated groups. Results: TER+ZOEA (17.16 ± 0.41 MPa) displayed the highest bond integrity. However, group PDT+EA (11.34 ± 0.25 MPa) demonstrated the lowest bond scores. The intergroup comparison revealed that the TER system displayed significantly higher SBS values than the PDT and ECYL groups (p < 0.05). The intragroup comparison revealed that enamel conditioned with TER and brackets bonded with ZOEA and EA displayed comparable bond integrity (p > 0.05). Conclusions: Enamel conditioned with TER bonded to a metallic bracket displayed better bond strength than PDT and ECYL. Zirconium oxide nanoparticles incorporated in adhesive have proved to be promising in improving the bond integrity of adhesive.

Periodontal, Microbiological, and Proinflammatory Cytokines Levels in Fixed Orthodontics Patients Treated with Photodynamic Therapy Adjunct to Full Mouth Scaling.

Objective: To assess the efficiency of photodynamic therapy (PDT) adjunct to full mouth scaling (FMS) in improving periodontal, microbiological, and proinflammatory cytokines levels in patients undergoing fixed orthodontics treatment (FOT). Materials and methods: The study recruited 60 teenage patients who were undergoing FOT. All the patients were arbitrarily divided into two groups: Group 1, FMS +PDT and Group 2, FMS alone. Plaque scores (PS), bleeding on probing (BOP), and probing depth (PD) were assessed. Levels of biomarkers interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α) using enzyme-linked immunosorbent assay were evaluated. Samples were collected from gingival plaque for estimation of Prevotella intermedia and Porphyromonas gingivalis load. All measurements were completed at three intervals baseline, 4th week, and 8th week. Post Hoc corrections and intergroup comparisons were examined using Student's t-test and Bonferroni correction. To find differences between repeated follow-ups, analysis of variance (ANOVA) multiple rank tests were used. Results: At baseline, all the gingival parameters displayed comparable outcomes between patients of Group 1 and Group 2 (p > 0.05). However, at 4 and 8 weeks of follow-up, PS and BOP among tested groups exhibited significantly lower values than baseline (p < 0.001). At 8 weeks, there was a significant difference in PS between the two groups tested. Moreover, at 4 and 8 weeks, BOP revealed a significant difference between the groups. PD remains comparable with baseline at follow-up visits (p > 0.05). A significant decrease in IL-6 and TNF-α levels was observed in both investigated groups at 4 and 8 weeks of baseline. Moreover, it was identified that P. intermedia and P. gingivalis were reduced significantly at 4 weeks. Moreover, a significant difference existed between both Group 1 and Group 2 at 4 and 8 weeks of recall visit (p < 0.05). Conclusions: The use of photodynamic treatment adjuvant to FMS aids in improving periodontal parameters and cytokines levels.

Bibliometric analysis and evaluation of the Journal of Prosthetic Dentistry from 1970 to 2019.

STATEMENT OF PROBLEM: A comprehensive bibliometric analysis to determine different aspects of the Journal of Prosthetic Dentistry is lacking. PURPOSE: The purpose of this bibliometric study was to analyze the characteristics of the Journal of Prosthetic Dentistry between 1970 and 2019. MATERIAL AND METHODS: The Web of Science Core Collection was used to retrieve 9 categories of the Journal of Prosthetic Dentistry, including keywords and terms used, cited documents published, the countries and organizations of the authors, references, and sources cited during this period. Data were exported to a software program and analyzed for each 10-year period and for the entire 50 years. The highest 10 in each category were reported. Co-occurrence, couthorships, and linkage were also reported. RESULTS: A total of 11 989 records were reached by the search on the Web of Science Core Collection database; of which, 10 638 (92.9%) were included in the analysis. Articles made up 91.1%, of all records, with 217 review documents (1.8%). The most productive decade was 1980 to 1989 with 2936 documents. The total number of citations of all documents (available period 1980 to 2019) including self-citations was 155 112. During the period 1970 to 2019, 14 837 terms were used. The total number of keywords was 4933 (available period 1990 to 2019). There were 15 382 authors, 82 countries, and 2113 organizations identified in articles published in the Journal of Prosthetic Dentistry during this period, with most from the United States. There were 43 027 authors, 95 324 references, and 14 594 sources cited in the Journal of Prosthetic Dentistry during the period surveyed. CONCLUSIONS: This bibliometric analysis provided a comprehensive overview of the impactful role of the Journal of Prosthetic Dentistry in contemporary dentistry, particularly in the field of prosthodontics.

Mouth shield to minimize airborne transmission risk of COVID-19 and other infectious diseases in the dental office.

Transmission of coronavirus disease (COVID-19) and other infectious diseases is a significant risk during dental procedures because most dental interventions involve aerosols or droplets that could contaminate the surrounding environment. Current protection guidelines to address the high risk of droplets, aerosols, and airborne particle transmission of COVID-19 in the dental office recommend minimizing aerosol-generating procedures. In this paper, an innovative mouth shield is presented that should minimize water backsplash from the air-water syringe during dental treatment. The mouth shield can be added to the personal protective equipment to provide the dental team with extra protection. It can be made of different materials, is straightforward, inexpensive, and safe to fabricate, and is easy to use.

Comparison between two asynchronous teaching methods in an undergraduate dental course: a pilot study.

BACKGROUND: Properly designed and implemented eLearning can lead to improvement of dental teaching quality. Various strategies have been proposed to increase the effectiveness of eLearning in dental education, however, there is a lack of research to assess the effectiveness of these strategies. OBJECTIVE: To investigate dental students' learning performance and perception of a virtual flipped learning format compared to a virtual traditional learning method. METHODS: A crossover pilot study was conducted at the College of Dentistry, Princes Sattam Bin Abdulaziz University, Saudi Arabia. Computer-generated randomization, blinded from researchers who analyzed the results, was performed to allocate 32 participants (aged 23.27 ± 0.86 years) to one of two groups. Participants in the control group were taught through the virtual traditional learning method (VTL) using live video lectures. In contrast, participants in the intervention group were taught through the virtual flipped learning method (VFL) using recorded online lectures and post-lecture virtual discussions. Learning gain and preference were measured by pre- and post-test average score differences and a modified validated survey, respectively. RESULTS: There was no significant difference in learning performance between VFL and VTL groups (P > 0.05). However, students preferred VFL over VTL and the differences were significant among all survey items, except for the opportunity to ask questions. CONCLUSION: Health professions educators are encouraged to carefully design online curricula with efficient learning strategies that help students improve learning performance and foster self-directed learning skills while valuing active learning in an online environment. TRIAL REGISTRATION: NCT04692142 , 31/12/2020.

Comparison of Salivary IGF-1, IGFBP-3, and CTX with Periodontal Status among Patients Belonging to Various Skeletal Maturity Groups.

PURPOSE: To compare the levels of salivary IGF-1, IGFBP-3, and CTX with periodontal status among patients belonging to various skeletal maturity groups. MATERIALS AND METHODS: This cross-sectional study was conducted on 80 participants 6 to 25 years of age. Based on skeletal maturity, the participants were categorised into 3 different stages: prepubertal, pubertal, and post-pubertal stages. The periodontal status of the participants was assessed using the simplified oral hygiene index (OHI-S), bleeding on probing (BOP), probing pocket depth (PPD), clinical attachment loss (CAL), and community periodontal index (CPI). The saliva samples were examined for IGF-1, IGFBP-3, and CTX using the respective ELISA kits. One-way ANOVA was used to determine statistically significant differences of means across the study groups for continuous variables. RESULTS: The study demonstrated statistically significant differences for the parameters OHI-S, bleeding on probing, PPD, CPI, and CAL (p < 0.05) depending on skeletal maturity stage. ANOVA test showed a statistically significant difference by stage in IGF-1, IGFPB3, and CTX (p < 0.01). CONCLUSION: An association exists between periodontal status and levels of salivary IGF-1, IGFBP-3, and CTX in patients belonging to various skeletal maturity groups.

Correlation between Salivary Levels of IGF-1, IGFBP-3, IGF-1/IGFBP3 Ratio with Skeletal Maturity Using Hand-Wrist Radiographs.

Objective: The relevance of growth determination in orthodontics is driving the search for the most precise and least invasive way of tracking the pubertal growth spurt. Our aim was to explore whether minimally invasive salivary estimation of biomarkers Insulin-like growth factor (IGF-1) and Insulin-like growth factor binding protein-3 (IGFBP-3) could be used to estimate skeletal maturity for clinical convenience, especially in children and adolescent age groups. Materials and Method: The cross-sectional study was conducted on 90 participants (56 girls and 34 males) with ages ranging from 6 to 25 years. Each subject's hand-wrist radiograph was categorized based on skeletal maturity, and saliva samples were estimated for IGF-1 and IGFBP-3 using the respective ELISA kits. Kruskal−Wallis nonparametric ANOVA was applied to compare different skeletal stages. Results: The study demonstrated low salivary IGF-1 levels at the prepubertal stage, with increase during pubertal onset and peak pubertal stage followed by a decline during pubertal deceleration to growth completion. Spearman's correlation coefficient demonstrated a strong positive association (r = 0.98 p < 0.01) between salivary IGF/IGFBP-3 ratio and different stages of skeletal maturity. Conclusion: Salivary IGF-1, IGFBP-3, and IGF/IGFBP-3 ratio could serve as a potential biochemical marker for predicting the completion of skeletal maturity.

Disinfection of radicular dentin using Riboflavin, Rose Bengal, Curcumin, and Porfimer sodium on extrusion bond strength of fiber post to radicular dentin.

AIM: To assess the influence of different photosensitizers activated by PDT as a disinfectant in comparison to conventional sodium hypochlorite (NaOCl) on the EBS (extrusion bond strength) of FRCP with radicular dentin. METHODS: A total of fifty single-rooted human maxillary central incisors with fully developed apices were selected. Endodontic treatment of samples was performed using 10 K file to obtain patency than sequentially with a 25 K file followed by rotary pro tapers till F2 with constant irrigation. The canal was dried and obturated with corresponding gutta-percha and sealer. A Peso reamer was employed to prepare post space. Based on canal disinfection regimes, samples were divided into five groups. Group 1 Riboflavin (RF)+17%EDTA, group 2 Rose bengal (RB) +17%EDTA, group 3 Curcumin CP +17%EDTA, group 4 Porfimer sodium, Photofrin (PS) +17%EDTA and group 5 2.25% NaOCl +17% EDTA (control). Following disinfection, the canal space of all specimens was dried followed by FRCP cementation. Specimens were placed on a Universal testing machine (UTM) for EBS. The type of bond failure was evaluated using a stereomicroscope. ANOVA and Tukey multiple comparison tests were used to compare means. RESULTS: The highest EBS was shown by group 1 canal disinfected with riboflavin (RF) and 17% EDTA at all three levels. The lowest EBS was displayed in group 5 canal cleaned with 2.25% NaOCl and 17% EDTA. Intragroup assessment disclosed a decrease in EBS from cervical one-third to apical one-third in all experimental groups. Intergroup comparison revealed group 4 using PS and 17% EDTA and group 5 canal disinfected with 2.25% NaOCl and 17% EDTA at all three levels of root structure coronal, middle, and apical exhibited comparable EBS (p>0.05). CONCLUSION: Root canal dentin treated with different PS (RF, RB, CP) has the potential to be used as canal disinfection as it demonstrates better EBS than the conventional disinfecting regime (2.25% NaOCl +17% EDTA). PS and 17% EDTA as a canal disinfectant need further investigation.

COVID-19 Vaccine Intention among Healthcare Workers in Saudi Arabia: A Cross-Sectional Survey.

The COVID-19 pandemic has caused largescale morbidity and mortality and a tremendous burden on the healthcare system. Healthcare workers (HCWs) require adequate protection to avoid onward transmission and minimize burden on the healthcare system. Moreover, HCWs can also influence the general public into accepting the COVID-19 vaccine. Therefore, determining COVID-19 vaccine intention among HCWs is of paramount importance to plan tailor-made public health strategies to maximize vaccine coverage. A structured questionnaire was administered in February and March 2021 among HCWs in Saudi Arabia using convenience sampling, proceeding the launch of the vaccination campaign. HCWs from all administrative regions of Saudi Arabia were included in the study. In total, 674 out of 1124 HCWs responded and completed the survey (response rate 59.9%). About 65 percent of the HCWs intended to get vaccinated. The intention to vaccinate was significantly higher among HCWs 50 years of age or older, Saudi nationals and those who followed the updates about COVID-19 vaccines (p < 0.05). The high percentage (26 percent) of those who were undecided in getting vaccinated is a positive sign. As the vaccination campaign gathers pace, the attitude is expected to change over time. Emphasis should be on planning healthcare strategies to convince the undecided HCWs into accepting the vaccine in order to achieve the coverage required to achieve herd immunity.

Predictors of COVID-19 Vaccine Intention among the Saudi Arabian Population: A Cross-Sectional Survey.

The long-term solution to managing the current COVID-19 pandemic is through mass immunization of the population. However, uncertainty or unwillingness to receive the vaccine could be a barrier in attaining sufficient vaccine coverage. Therefore, understanding the psychology of the population towards the vaccines against COVID-19 is of paramount importance. Our study was aimed at determining the predictors of COVID-19 vaccine intention in the Saudi Arabian population. A structured questionnaire guided by the 'Report of the SAGE working group on vaccine hesitancy' was administered during a span of two months among the general population from all administrative regions of Saudi Arabia, proceeding the launch of the vaccination campaign. In total, 879 out of 1600 subjects responded and completed the survey (response rate 54.9%). About 56 percent of the participants intended to be vaccinated. The predictors of a higher intention to vaccinate included those 50 years of age or older, male subjects, people suffering from systemic disease/s, subjects who were not previously infected with COVID-19, those who follow the updates about COVID-19 vaccines, and adults with a higher level of anxiety about contracting coronavirus (p < 0.05). Results from our study and other similar studies can aid policy makers and stakeholders in planning effective strategies based on the changing behavior of the population.

Age estimation based on Willems method versus country specific model in Saudi Arabia children and adolescents.

BACKGROUND: The aims of this study were to create a method for estimation of dental age in Saudi children and adolescents based on the Willems model developed using the Belgian Caucasian (BC) reference data and to compare the ability of the two models to predict age in Saudi children. METHODS: Development of the seven lower left permanent mandibular teeth was staged in 1146 panoramic radiographs from healthy Saudi children (605 male, 541 female) without missing permanent teeth and without all permanent teeth fully developed (except third molars). The data were used to validate the Willems BC model and to construct a Saudi Arabian-specific (Willems SA) model. The mean error, mean absolute error, and root mean square error obtained from both validations were compared to quantify the variance in errors in the sample. RESULTS: The overall mean error for the Willems SA method was 0.023 years (standard deviation, ± 0.55), indicating no systematic underestimation or overestimation of age. For girls, the error using the Willems SA method was significantly lower but still negligible at 0.06 years. A small but statistically significant difference in total mean absolute error (11 days) was found between the Willems BC and Willems SA models when the data were compared independent of sex. The overall mean absolute error for girls was slightly lower for the Willems BC method than for the Willems SA method (1.33 years vs. 1.37 years). CONCLUSIONS: The difference in ability to predict dental age between the Willems BC and Willems SA methods is very small, indicating that the data from the BC population can be used as a reference in the Saudi population.

Minimally Invasive Resin-Bonded Inlay-Retained Cantilever Fixed Dental Prosthesis: A Clinical Report.

This clinical report demonstrates the treatment of a healthy adult patient referred for prosthodontic treatment after orthodontic treatment with a resin-bonded inlay-retained cantilever fixed dental prosthesis (IRCFDP). The purpose of this report was to demonstrate the esthetic, functional, and conservative properties of a resin-bonded IRCFDP fabricated from monolithic zirconia which can be placed in posterior area in certain situations. Acceptable esthetics with a conservative and functional result were achieved by using a resin-bonded inlay-retained cantilever fixed dental prosthesis (IRCFDP). All laboratory and clinical procedures of this case report are described.

Lithium di silicate ceramic surface treated with Er,Cr:YSGG and other conditioning regimes bonded to orthodontic bracket.

AIM: To assess bond integrity and modes of failure of metallic brackets to lithium disilicate ceramics (LDC) conditioned with Er,Cr:YSGG laser (ECL). MATERIAL AND METHODS: Sixty LDC were arbitrarily allocated into six groups (n = 15) according to the type of ceramic surface conditioning treatment. Group 1 surface treated with silane (S) only, group 2 surface etched with hydrofluoric acid (HF)+ S, group 3 surface conditioned with HF+ ultrasonic bath (UB)+ S, group 4 sand blasting (SB) of glass ceramic surface with 50 µm Al2O3, group 5 surface conditioned with self-etch ceramic primer (SECP) and in group 6 surface treated with ECL + S. After conditioning, the specimens were positioned in a universal testing device for shear bond strength (SBS) testing. Adhesive Remnant Index (ARI) was used to determine sites of bond failure. Among experimental groups analysis of variance (ANOVA) and Tukey multiple comparison test was used at a significance level of (p < 0.05). RESULTS: The highest SBS values were observed in group 3 HF+ UB + S (18.21 ± 1.241) and the lowest SBS values were displayed group 1 surface treated with S only (5.21 ± 0.23). Specimens surface conditioned in group 2 with HF+ S (17.85 ± 1.25), group 3 HF+ UB + S (18.21 ± 1.241) and group 6 ECL + S (17.09 ± 1.114) unveiled comparable SBS values (p > 0.05). CONCLUSION: LDC conditioned with ECL at (4.5 W and 30 Hz) has a potential to be used in clinical settings alternate to HF acid.

Anterior loop of the mental nerve in Saudi sample in Riyadh, KSA. A cone beam computerized tomography study.

BACKGROUND: The portion of inferior alveolar nerve (IAN) existent anterior to the mental foramen, before parting the canal, is referred to as the anterior loop (AL) of the IAN. The presence of AL is important when placing the implant interforaminal area of the mandible. These anatomical discrepancies can be assessed by cone-beam CT (CBCT), for evaluating its position and exact location. The AL is classified into Types I, II and III. In Type I, Y-shaped anatomy; in Type II, anatomy is T-shaped; and in Type III, Y-shaped anatomy is seen, and the incisive branch is thicker as compared to the main branch. AIM: In this study, we aim to analyse the prevalence of different types of AL of the IAN in Saudi sample population. MATERIALS AND METHODS: The present study is a retrospective analysis of 149 (86 female & 63 male) CBCT images of patients records from 2018 June to 2018 September in the department of implant dentistry, KSMC, Riyadh. The age range of the patients who participated in the study was 30-60 years. The mean age of female participants is 42.5 ± 5.8, for the male participants is 48.6 ± 11.4 years respectively. RESULTS: The most frequent type of AL of mental nerve noticed on the right side was of type I (59.1%), followed by type II (27.5%) and type III (13.4%). The most frequent type of AL of mental nerve noticed on the left side was type I (61.7%), followed by type II (26.8%) and type III (11.4%). CONCLUSION: The results of the study encourage the usage of CBCT for planning implant treatment. We also suggest that it is obligatory for professionals to categorise the presence of AL and to measure them appropriately when planning for the procedures in the interforaminal region.

Effectiveness of Riboflavin and Rose Bengal Photosensitizer Modified Adhesive Resin for Orthodontic Bonding.

This study aimed to evaluate the effect of riboflavin (RF) and Rose Bengal (RB) photosensitizer modified adhesive resin on the degree of conversion (DC), and antimicrobial capacity after bonded to tooth surface. Different concentrations of RB and RF were prepared by homogenization method. An ultraviolet light source A (UVA) (375 nm wavelength, 3 mW/cm2 power) was used for 30 min irradiation. FTIR was performed for control and test adhesives to analyze the DC. Antibacterial testing was performed using the MTT assay. Metal brackets were bonded using the modified adhesives and subjected for SEM examination. The surfaces of teeth and metal brackets were examined at ×10 magnification for assessing adhesive remnant index (ARI) after PDT, 24 h and thermocycling. For DC, control group, 0.1% RB and RF after PDT showed the highest value. SEM imaging indicated lowest growth of Streptococcus mutans over 0.5% of RB-PDT and RF-PDT as compared to the control group. The MTT assay outcomes reported that the activity of S. mutans substantially decreased with the addition of a high amount of either RB or RF (p < 0.01). Mean ARI scores showed a significant difference between all groups. This study concluded that 0.1% of either RB or RF after PDT can be used for bonding orthodontic brackets to the tooth surface with substantial antibacterial properties.

A Global Survey of COVID-19 Vaccine Acceptance Among Healthcare Workers.

Objectives: Even though several effective vaccines are available to combat the COVID-19 pandemic, wide disparities in vaccine distribution, and vaccine acceptance rates between high- and low-income countries appear to be major threats toward achieving population immunity. Our global descriptive study aims to inform policymakers on factors affecting COVID-19 vaccine acceptance among healthcare workers (HCWs) in 12 countries, based on income index. We also looked for possible predictors of vaccine acceptance among the study sample. Methods: A structured questionnaire prepared after consultation with experts in the field and guided by the "Report of the SAGE working group on vaccine hesitancy" was administered among 2,953 HCWs. Upon obtaining informed consent, apart from demographic information, we collected information on trust in vaccines and health authorities, and agreement to accept a COVID-19 vaccine. Results: Although 69% of the participants agreed to accept a vaccine, there was high heterogeneity in agreement between HCWs in low and lower-middle income countries (L-LMICs) and upper-middle- and high-income countries (UM-HICs), with acceptance rates of 62 and 75%, respectively. Potential predictors of vaccine acceptance included being male, 50 years of age or older, resident of an UM-HIC, updating self about COVID-19 vaccines, greater disease severity perception, greater anxiety of contracting COVID-19 and concern about side effects of vaccines. Conclusions: COVID-19 vaccine acceptance among HCWs in L-LMICs was considerably low as compared to those from UM-HICs. The lowest vaccine acceptance rates were among HCWs from the African continent. This underlines the need for the implementation of country-specific vaccine promotion strategies, with special focus on increasing vaccine supply in L-LMICs.

The relationship between malocclusion and oral health-related quality of life among adolescents: a systematic literature review and meta-analysis.

BACKGROUND: Malocclusion is a deviation from an anatomical norm that occurs in various populations. Evidence shows that it has physical and psychological implications as well as an influence on the patient's oral health-related quality of life (OHRQoL). Self-perception of oral health plays an important role in the understanding of malocclusion's influence on the quality of life. Malocclusion has been reported to impair a patient's function, appearance, interpersonal relationships and psychological well-being. OBJECTIVES: The aim of this study was to investigate whether adolescents aged between 11 and 18 years with malocclusion are at increased risk for having a high level of OHRQoL compared with those without malocclusion. SEARCH METHODS: The Ovid Medline, Embase and Scopus databases were used to identify studies measuring the association between malocclusion and HRQoL. SELECTION CRITERIA: Only cross-sectional studies were included, and the following inclusion criteria were used: subjects were systemically healthy; data were available for untreated malocclusion and OHRQoL; malocclusion was measured by Dental Aesthetic Index and Index of Orthodontic Treatment Needs; OHRQoL was assessed by Child Perception Questionnaire, Child Oral Health Impact Profile and Child Oral Health Impact Profile; and the paper was published in English. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers. The Appraisal tool for Cross-Sectional Studies (AXIS) was used to establish the risk of bias, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) evidence quality assessment tool was used to assess the impact of malocclusion on adolescents across studies. RESULTS: The initial search yielded 530 papers. Eleven cross-sectional studies were included in the meta-analyses, and all data describing the relationship between malocclusion and OHRQoL were gathered via a structured questionnaire. Our results showed that malocclusion is linked to decreased OHRQoL in children and adolescents aged between 11 and 18 years in continuously analysed studies. However, in dichotomously analysed studies, it was shown that young people without malocclusion are linked to decreased OHRQoL. CONCLUSIONS: Adolescents with severe levels of malocclusion might have among the worst levels of OHRQoL. The effects of malocclusion on OHRQoL were influenced by the age of the adolescents as well as by their culture and environment. REGISTRATION: PROSPERO (CRD42020178657).

Influence of photodynamic therapy and different lasers Er,Cr:YSGG and Er,YAG on dentin conditioning bonded to conventional and bioactive cement.

AIM: The aim of the present study was to evaluate the bond integrity of bioactive cement (BAc) in contrast to conventional cement Calibra (C) after dentin treated with different surface conditioners (PDT, EYL, ECL) MATERIALS AND METHODS: Sixty non-carious permanent mandibular molars were disinfected and embedded in acrylic resin till cement-o-enamel junction. For homogeneity the buccal surface were grounded and polished. Samples were categorized into three main groups based on conditioning technique. Samples in group 1 and 2 dentin conditioned with Er,Cr:YSGG (ECL), group 3 and 4 surface treated with Er:YAG (EYL) and group 5 and 6 treated with photodynamic therapy (PDT).On conditioned surface bonding agent was applied and light cured. Samples from group 1,3,5 were bonded to Calibra (C). Whereas, specimens in group 2,4,6 were conditioned with bioactive cement (BAc) and subjected to ageing followed by shear bond strength testing (SBS) in universal testing machine. To detect significance difference between means of different groups analysis of variance (ANOVA) was performed followed by Tukey's post-hoc tests. RESULTS: The maximum SBS was displayed in group 1, dentin conditioned with ECL and bonded to C (20.23 ±â€¯0.47 MPa). Whereas, group 6, PDT of dentin to BAc demonstrated lowest bond integrity among experimental groups (12.97 ±â€¯0.25 MPa). Bond strength of group 1, ECL-C (21.55 ±â€¯3.08 MPa) and group 3 EYL-C (19.11 ±â€¯0.65 MPa) were comparable (p > 0.05). Group 5 samples treated with PDT, MB-C (13.41±0.32 MPa) and group 6, MB-BAc (12.97 ±â€¯0.25 MPa) were also comparable (p > 0.05) CONCLUSION: BAc bonded to dentin after surface conditioning with ECL, EYL and PDT presented lower SBS in comparison to conventional cement C. Further studies are required to extrapolate the current findings.