Perception of discrepancy in the upper midline position in conjunction with the gingival display according to various occupations in Iran.

Objective: This study evaluated the influence of various gingival displays on the esthetic perception in the presence of upper dental midline discrepancy. Methods: A smiling image of a male subject was altered digitally to produce five image series: normal smile (series A), decreased tooth show (series B), increased gingival show (series C), maxillary cant (series D), and asymmetric upper lip elevation (series E). In each image series, the midline was deviated to the right and left incrementally. A total of 210 raters (four professional groups and laypersons, n = 42 in each group) determined the midline deviation threshold and the attractiveness of midline position in each series. Results: The right and left thresholds were statistically similar for the symmetrical series (A, B, and C), while for series D, the right threshold was significantly lower. In most rater groups, the mean threshold order was: B > A > E > C > D. In all the series, the raters selected the coincident midline as the most attractive series except for series D, for which 1-2-mm deviations to the left were selected as the most attractive by almost all the groups. Conclusions: It is crucial to establish the coincident midline position in a symmetrical smile, especially when a gummy smile exists. In the asymmetrical gingival show, a coincident midline might not be the most esthetic midline position.

Effect of 8% arginine toothpaste on Streptococcus mutans in patients undergoing fixed orthodontic treatment: randomized controlled trial.

OBJECTIVE: To assess the effect of toothpaste containing 8% arginine on Streptococcus mutans (S. mutans) in dental plaque around orthodontic brackets, and to draw a comparison with a regular fluoride toothpaste. TRIAL DESIGN: A single-center, parallel-arm, triple-blind, randomized controlled trial was conducted. METHODS: The clinical trial was conducted at the Orthodontic Clinic, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. Seventy-two patients (age range: 15-30 years) who required fixed orthodontic treatment were recruited and randomly assigned to arginine and fluoride groups. Randomization was performed using RANDOM.ORG online software, and the participants were divided into two parallel groups, with a 1:1 allocation ratio. Patients were requested to brush their teeth twice daily for 30 days with an experimental toothpaste. Plaque sampling was performed at two intervals, namely at the beginning of the study (T0) and 30 days later (T1). Real-time PCR was used to assess plaque samples in terms of the number of S. mutans surrounding stainless steel brackets in orthodontic patients. A triple-blind design was employed. RESULTS: The baseline characteristics (age, sex, and the relative number of S. mutans) between the groups were similar (p>0.05). Only the arginine group showed a significant decrease in the relative number of bacteria between T0 and T1 (p=0.02). CONCLUSION: Arginine is an important prebiotic agent in maintaining healthy oral biofilms, and prevent dental caries during fixed orthodontic treatments. TRIAL REGISTRATION: The trial was registered at the Iranian Registry of Clinical Trials (IRCT20181121041713N2), https://en.irct.ir/user/trial/42409/view.

Preventive practice, vaccine acceptance, and knowledge toward coronavirus disease-19: An online cross-sectional questionnaire-based report in Iranian dentists.

BACKGROUND: The coronavirus disease (COVID) is predicted to cause serious mental health problems among healthcare providers (HCPs) especially dentists. Also understanding the influencing factors of the acceptance of COVID-19 vaccination among HCPs are important aspects in the design of effective strategies to improve the vaccine coverage rate. Therefore, this study aimed to assess the knowledge, vaccination acceptance, fear, and obsession, as well as the preventive practice behaviors of Iranian dentists and dental students in late 2020 toward COVID-19. MATERIALS AND METHODS: A descriptive, web-based cross-sectional survey was conducted among Iranian dental students and dentists (general practitioners and specialists). All Iranian dentists and dental students living in the Islamic Republic of Iran regardless of their city and workplace were invited to participate in the study. The total number of dentists in Iran was estimated to be 54,927. The sample size was calculated 380. The questionnaires used in this study were adapted from previously published studies based on the authors' permission. The questionnaire consisted of four sections that sought to collect information on the respondents' vaccination acceptance, knowledge, preventive practice, fear, and obsession toward COVID-19. The relationship between the study variables was assessed using Pearson's correlation coefficient and also multiple linear regression tests. RESULTS: Overall, 394 dentists were filled the questionnaire (65 dental students, 151 general dentists and 178 specialists). There were no differences in terms of vaccination acceptance, knowledge and also fear score in different designation groups. Dentists had significantly higher obsession and also preventive practice scores than other designation groups (P < 0.05). The majority of respondents had good knowledge (more than 9), acceptable preventive practice (more than 19), low fear-obsession (<2.7), and high acceptance of COVID-19 vaccination (more than 8.8). CONCLUSIONS: Although obsession and fear scores were low in all designation groups, dentists had higher obsession and also preventive practice scores than other designation groups. More than half of respondents preferred imported COVID-19 vaccines. Finally, organizations such as the World Health Organization and the Ministry of Public Health in Iran should increase vaccine convenience and accessibility in terms of vaccine importing, distribution, supply, and immunization service.

Effect of 8% arginine toothpaste on Streptococcus mutans in patients undergoing fixed orthodontic treatment: randomized controlled trial

ABSTRACT Objective: To assess the effect of toothpaste containing 8% arginine on Streptococcus mutans (S. mutans) in dental plaque around orthodontic brackets, and to draw a comparison with a regular fluoride toothpaste. Trial design: A single-center, parallel-arm, triple-blind, randomized controlled trial was conducted. Methods: The clinical trial was conducted at the Orthodontic Clinic, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. Seventy-two patients (age range: 15-30 years) who required fixed orthodontic treatment were recruited and randomly assigned to arginine and fluoride groups. Randomization was performed using RANDOM.ORG online software, and the participants were divided into two parallel groups, with a 1:1 allocation ratio. Patients were requested to brush their teeth twice daily for 30 days with an experimental toothpaste. Plaque sampling was performed at two intervals, namely at the beginning of the study (T0) and 30 days later (T1). Real-time PCR was used to assess plaque samples in terms of the number of S. mutans surrounding stainless steel brackets in orthodontic patients. A triple-blind design was employed. Results: The baseline characteristics (age, sex, and the relative number of S. mutans) between the groups were similar (p>0.05). Only the arginine group showed a significant decrease in the relative number of bacteria between T0 and T1 (p=0.02). Conclusion: Arginine is an important prebiotic agent in maintaining healthy oral biofilms, and prevent dental caries during fixed orthodontic treatments. Trial registration: The trial was registered at the Iranian Registry of Clinical Trials (IRCT20181121041713N2), https://en.irct.ir/user/trial/42409/view.

RESUMO Objetivo: Avaliar o efeito de um dentifrício contendo arginina a 8% no Streptococcus mutans (S. mutans) da placa bacteriana ao redor de braquetes ortodônticos, e compará-lo a um dentifrício fluoretado convencional. Desenho do estudo: Foi conduzido um estudo unicêntrico, com braços paralelos, triplo-cego, controlado e randomizado. Métodos: O ensaio clínico foi conduzido na Clínica de Ortodontia da Faculdade de Odontologia da Universidade de Ciências Médicas de Shiraz, no Irã. Setenta e dois pacientes (com idades variando de 15 a 30 anos) que necessitavam de tratamento ortodôntico com aparelho fixo foram recrutados e alocados aleatoriamente nos grupos arginina ou flúor. A randomização foi feita usando o programa on-line RANDOM.ORG, e os participantes foram divididos em dois grupos paralelos, com proporção de alocação de 1:1. Solicitou-se aos pacientes que escovassem os dentes duas vezes ao dia com a pasta experimental, durante 30 dias. Amostras da placa bacteriana foram coletadas em dois intervalos: ao começo do estudo (T0) e após 30 dias (T1). Um PCR em tempo real foi usado para avaliar as amostras de placa, em termos de números de S. mutans ao redor dos braquetes de aço inoxidável nos pacientes ortodônticos. Um desenho de estudo triplo-cego foi usado. Resultados: As características iniciais (idade, sexo e quantidade relativa de S. mutans) foram semelhantes entre os grupos (p>0,05). Apenas o grupo arginina mostrou uma redução significativa na quantidade de bactérias entre T0 e T1 (p=0,02). Conclusão: A arginina é um agente prebiótico importante na manutenção de biofilmes bucais saudáveis, e previne as cáries dentárias durante o tratamento ortodôntico com aparelho fixo. Registro do ensaio: O ensaio foi registrado no Iranian Registry of Clinical Trials (IRCT20181121041713N2), https://en.irct.ir/user/trial/42409/view.

Are individuals with orofacial pain more prone to psychological distress during the COVID-19 pandemic?

BACKGROUND: It is of utmost importance to identify and treat groups susceptible to psychological problems during the coronavirus disease 2019 (COVID-19) pandemic. OBJECTIVES: This study aimed to compare the psychological status between the general population and subjects with orofacial pain (OFP) during the COVID-19 pandemic. MATERIAL AND METHODS: A total of 509 young adults were recruited based on the inclusion and exclusion criteria, using the convenient sampling approach. They were assigned to 2 study groups: group 1 - individuals with OFP; and group 2 - the general population. Their background variables, knowledge, perception, attitude, concerns, and Kessler scale scores were recorded through an online questionnaire. Student's t test, the χ2 test, Pearson's correlation coefficient, and one-way analysis of variance (ANOVA) were used for the statistical analysis. RESULTS: Some of the background variables were significantly different between the study groups (p < 0.05). The knowledge, perception and attitude scores of the respondents were not significantly different between the study groups (p > 0.05). Females exhibited significantly higher adjusted Kessler scores as compared to males (p < 0.05). Group 1 exhibited the highest adjusted Kessler scores (p < 0.05). CONCLUSIONS: Individuals with OFP exhibited higher psychological distress, depressive symptoms and anxiety during the rapid rise of the COVID-19 outbreak, representing a moderate psychological disorder. Females suffered more from psychological distress as compared to males. Therefore, psychological interventions should be focused on this group.

Evaluation of the Preventive Effect of Composites Containing Silver and TiO2 Nanoparticles on Demineralization around Orthodontic Brackets.

AIM: The aim of this study was to investigate the antidemineralization effect of composites containing silver and titanium dioxide (TiO2) nanoparticles used for bonding brackets to tooth specimens. MATERIALS AND METHODS: A total of 75 freshly extracted teeth were etched and primed and then randomly assigned to three adhesive groups: (1) conventional orthodontic adhesive, (2) conventional adhesive mixed with TiO2 nanoparticles, and (3) conventional adhesive mixed with silver nanoparticles. In each group, brackets were bonded with the pertinent adhesive. Teeth were painted with varnish on all surfaces except a 2-mm rim around brackets. Specimens were subjected to a cariogenic process in a circulating microbial model inoculated with Streptococcus mutans and Lactobacillus casei for 12 days and subsequently sectioned for cross-sectional microhardness testing. In each specimen, enamel microhardness was determined in three locations: 25-30 µm and 1.5 mm away from the bracket and under the varnish-protected enamel. Hardness of enamel in the first two locations was reported as a percentage of the protected enamel hardness. RESULTS: Enamel hardness was higher at 25-30 µm away from brackets in both the experimental groups (p value < 0.05), and the nanoparticles acted similarly in this location (p value = 0.992). At 1.5 mm away from the brackets, there was no difference between experimental and control groups (p value > 0.05); the effect of TiO2 attenuated in this location while silver remained as potent. CONCLUSION: Both nanoparticles resulted in decreased demineralization at 25-30 µm from the bracket but farther away the effect of TiO2 was diminished. CLINICAL SIGNIFICANCE: According to the results of this study, composites containing silver and TiO2 nanoparticles can be suggested as anti-demineralization adhesives in case their biocompatibility is proved.