Salivary oxidative stress biomarkers in periodontitis-free smokers: a cross sectional study.

BACKGROUND: Salivary oxidative stress has been extensively studied with attempts to correlate changes in the oxidative stress markers with local and systemic factors, including smoking. The objective of this study was to evaluate the influence of two forms of smoking, cigarettes and waterpipe smoking (WPS), on selected oxidative stress biomarkers in saliva. METHODS: Three groups of participants were enrolled into the study, controls (never smokers), cigarette smokers and WPS. Participants were clinically free from periodontitis and systemic conditions known to affect the saliva constituents. Unstimulated whole saliva samples were collected according to a standard protocol and concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG), myeloperoxidase (MPO), malondialdehyde (MDA), total antioxidant capacity (TAC), and cortisol. The one-way ANOVA test was used to compare the levels of each oxidative stress biomarker between the three study groups and the hierarchical linear regression analysis was used to test the levels of salivary cortisol for prediction of other oxidative stress biomarkers. Significance levels were set at 95% confidence intervals and probability values ≤0.05. RESULTS: 8-OHdG was highest in WPS group (mean±SE 11,030.35±1829.16 pg/mL) while MDA and cortisol levels were highest in the cigarette smokers group (mean±SE 3.33±0.52 µM and 3.99±0.48 ng/mL, respectively) and MPO was highest in the control group (mean±SE 7.760±1.55 ng/mL). WPS group showed the highest TAC (mean±SE 0.3±0.03 mM). However, none of the tested makers reached a statistically significant difference. CONCLUSIONS: Despite subtle changes in some biomarkers, the salivary oxidative stress does not appear to be significantly influenced by smoking habits in periodontitis-free smokers.

Comparative analysis of diagnostic accuracy in endodontic assessments: dental students vs. artificial intelligence.

OBJECTIVES: This study evaluates the comparative diagnostic accuracy of dental students and artificial intelligence (AI), specifically a modified ChatGPT 4, in endodontic assessments related to pulpal and apical conditions. The findings are intended to offer insights into the potential role of AI in augmenting dental education. METHODS: Involving 109 dental students divided into junior (54) and senior (55) groups, the study compared their diagnostic accuracy against ChatGPT's across seven clinical scenarios. Juniors had the American Association of Endodontists (AEE) terminology assistance, while seniors relied on prior knowledge. Accuracy was measured against a gold standard by experienced endodontists, using statistical analysis including Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner tests. RESULTS: ChatGPT achieved significantly higher accuracy (99.0 %) compared to seniors (79.7 %) and juniors (77.0 %). Median accuracy was 100.0 % for ChatGPT, 85.7 % for seniors, and 82.1 % for juniors. Statistical tests indicated significant differences between ChatGPT and both student groups (p<0.001), with no notable difference between the student cohorts. CONCLUSIONS: The study reveals AI's capability to outperform dental students in diagnostic accuracy regarding endodontic assessments. This underscores AIs potential as a reference tool that students could utilize to enhance their understanding and diagnostic skills. Nevertheless, the potential for overreliance on AI, which may affect the development of critical analytical and decision-making abilities, necessitates a balanced integration of AI with human expertise and clinical judgement in dental education. Future research is essential to navigate the ethical and legal frameworks for incorporating AI tools such as ChatGPT into dental education and clinical practices effectively.

Health-related quality of life and satisfaction following orthognathic surgery: a prospective cohort study.

PURPOSE: This study investigates the motivations for orthognathic surgery and assesses the quality of life (QoL) and satisfaction among patients treated at a hospital over 12 months. METHODS: We employed an Arabic version of the Orthognathic Quality of Life Questionnaire (OQLQ), used pre-surgery and at 2 weeks, 3 months, and 6 months post-surgery. This included demographic data, the OQLQ, and visual analogue scales (VAS). The OQLQ, originally by Cunningham et al., was translated and adapted by Al-Asfour et al. Additional validated questions were added to both pre- and post-operative surveys. RESULTS: Of 136 participants (51 males, 85 females, average age 25.1), most underwent surgery for facial aesthetics (85.2%) and bite correction (57.3%). Treatments included various osteotomies. OQLQ scores significantly dropped from 63.3% pre-surgery to 23% at 6 months, showing QoL improvement. 97.8% reported better psychological status post-surgery (p = 0.0001), with 94.1% satisfaction at 6 months (p = 0.0001). CONCLUSION: The orthognathic surgery yielded positive outcomes in functional and psychological aspects, leading to high satisfaction and improved QoL in patients with dentofacial deformity.

Development and validation of an assessment sheet for all-ceramic crown preparations: A methodological study.

Background: Dental students learn and practice clinical procedures in clinical skills laboratories. These practices are graded by qualified staff to evaluate the effectiveness of their learning. Valid evaluation requires accuracy and reliability. Although a well-developed checklist for pre-clinical skill evaluation exists in theory, it is challenging to implement in practice. This study was undertaken to develop and evaluate the reliability of an assessment sheet for all-ceramic crown preparations. Methods: The study consisted of two phases: the development stage and the judgment-quantification stage. Two examiners evaluated all-ceramic crown preparations made by second-year dental students using the developed assessment sheet to test criterion validity. The final grade was determined based on the number of errors identified using the assessment sheet. The relationship between the negative points and the final grades awarded was determined using Spearman's correlation. The study calculated the intra- and inter-examiner agreement for two rounds of evaluation, conducted one month apart, using Cohen's unweighted Kappa test. The study employed the Item-Content Validity Index (I-CVI) to evaluate the content validity for each item and the Scale-Content Validity Index (S-CVI) to assess the content validity of the overall scale used in all-ceramic crown preparation procedures. Results: The assessment sheet developed for all-ceramic crown preparations was reliable, with strong content validity and a significant negative correlation between grades assigned and the number of errors observed. The assessment sheet defined up to three levels of performance for each item, providing a consistent and objective approach to evaluation. The linear regression graph successfully determined the maximum number of acceptable errors and established the minimum passing grade. The inter- and intra-examiner agreement for the two assessment rounds was found to be fair to moderate. Conclusion: The study showed that the developed assessment sheet for all-ceramic crown preparations is reliable and can provide a consistent and objective approach to evaluation. It can benefit both students and instructors. Further research is recommended to evaluate the impact of the developed assessment sheet on students' learning outcomes.

Breaking the error chain with SEE: cascade analysis of endodontic errors in clinical training.

The ongoing endeavors to uncover the link between the prevalent errors in clinical endodontic training and undergraduate education are founded on tentative assumptions. This investigation was aimed at determining if cascade analysis can provide an understanding of the origins and causes of errors and if the sensitivity of student reports to the impact of errors on treatment outcomes can be established.In 2021, a group of investigators from the endodontics department concerned with clinical dental education launched the Study of Endodontic Errors (SEE). Sixty-six undergraduate dental students at one dental teaching hospital submitted anonymous narratives of problems they witnessed in their root canal treatment practices. The reports were examined to determine the sequence of events and the major errors. We kept track of the consequences of treatment outcomes, both as reported by students and as deduced by investigators.In 77% of the narratives, a chain of errors was recorded. The majority of the errors that took place were related to the working length or width of root canals. A substantial portion, 86%, of these errors could have been prevented through a deeper comprehension of the concepts that underlie working length and width. 75% of the errors that initiated cascades involved losing the correct working length. When asked whether the treatment outcome was compromised, students answered affirmatively in 16% of cases in which their narratives described compromised outcomes. Unacceptable outcomes necessitating re-treatment accounted for only 3% of student-reported consequences, but when investigator-inferred consequences were considered, the percentage more than doubled (7%).Cascade analysis of student error narratives is useful in understanding the triggering chain of events, but students provide insufficient information about how treatment outcomes are affected. Misconceptions about working length and width appear to play a significant role in the propagation of procedural errors.

Prevalence of mesio-distal dilaceration in patients presenting for initial orthodontic care: A retrospective study.

OBJECTIVE: To determine the prevalence of dilaceration in a sample of patients presenting for initial orthodontic care. METHODS: Examining radiographs from a random sample of orthopantomogram images was used to acquire the data. In all, 2,801 dental records were evaluated at Oman Dental College (ODC), Oman. A dental X-ray processing software was utilized to view the images. A tooth was classified as having a mesial/distal dilaceration if its long axis exhibited an angle of 90 degrees or greater. Dilacerated roots in the buccal/lingual direction were diagnosed by observing the appearance of a spherical opaque area with a dark shadow in its central region, projected by the apical foramen, which gave the root canal a "bull's-eye" appearance. RESULTS: Dilacerations were found in 17.32% of the records examined. The maxillary second molars (22.71%) were the most commonly affected, followed by the mandibular third molars and mandibular lateral incisors (21.90% and 17.23%, respectively). The central incisors and canines were the least affected, with dilaceration affecting less than 0.2% of the teeth. The mandible was found to have more dilacerations than the maxilla (53.78% and 46.22%, respectively). 61.03% of dilacerations occurred in molars, 43.12% of which occurred in third molars. CONCLUSION: Dilaceration is a notable dental anomaly that can affect any tooth, with some teeth being more affected than others. Dilaceration in maxillary second molars and mandibular lateral incisors is more common in the population of this study than in other populations reported in the literature. Recognizing the condition will allow for more effective orthodontic treatment.

Evaluating the Role of Inorganic Elements of Camelus Dromedarius Saliva in Protecting Enamel Against Tooth Surface Loss.

The aim of this study was to provide insight into the role of camel's saliva in protecting enamel against erosion and to evaluate the levels of salivary sodium, potassium, calcium, and phosphate ions among 2 groups of camels, those with low-grade tooth surface loss and those with high-grade tooth surface loss. Twenty-eight healthy camels, 5 males and 23 females, aged 20 months to 10 years, were divided into 2 groups. Group I comprise camels with "low-grade tooth surface loss" and Group 2 with "high-grade tooth surface loss." Unstimulated saliva was collected by a draining method. The samples were then analyzed for sodium, potassium, calcium, and phosphate concentrations using automated chemistry analysis. Data were then statistically analyzed using the unpaired Student's t-test and Pearson correlation coefficient test. The study found the salivary calcium and phosphate concentrations were significantly lower in the "high-grade" erosion group, in comparison with the other group (P < .0001 and P = .0257, respectively). The results also revealed that the more extensive the tooth surface loss, the more carious lesions the subject had (P = .023), and that caries are more common in the anterior teeth, particularly the incisors. The authors conclude that alterations in inorganic elements of saliva, particularly the calcium and phosphate ions, play a major role in the development of resistance to tooth surface loss. This work may represent a direction for future research to develop custom-made preventive supplements, which can protect camelid teeth against tooth surface loss.

Evaluation of Struthio camelus eggshell as an in vitro alternative to extracted human teeth in preliminary screening studies on dental erosion.

OBJECTIVES: This in vitro work investigates the potential of ostrich eggshell as a substitute for extracted human teeth in preliminary screening studies on dental erosion. Additionally, it aims to demonstrate the potential of ostrich eggshell compared to human enamel in evaluating the efficacy of a preventive agent in protecting against dental erosion, using an artificial mouth model. METHODS: The experiment utilized 96 erosion testing specimens from each substrate, human enamel, and ostrich eggshell. The specimens were subjected to six different experimental regimens of increasing erosive challenge, simulating the consumption of an acidic drink. The acidic drink was delivered at a consistent volume and duration range. Both artificially stimulated and unstimulated saliva flowed throughout the experimental regimens. Surface hardness was measured using a Through-Indenter Viewing hardness tester with a Vickers diamond, while surface profiling was done using a surface contacting profilometer with a diamond stylus. An automated chemistry analyzer system was used to detect calcium and phosphate ions. RESULTS: The study found that ostrich eggshell specimens demonstrated predictable surface loss, hardness drop, and ion loss due to the acidic challenge. Meanwhile, enamel appeared to fall short in terms of surface hardness predictability. The transient hardness loss phase, which manifests as an overlooked decrease in surface hardness despite significant ion and structural loss, may explain this phenomenon. CONCLUSIONS: The experiment showed that assessing surface loss is essential in addition to hardness testing, particularly as certain experimental conditions may produce a false perception of tissue recovery despite the actual surface loss. By analyzing the response of ostrich eggshell specimens to erosive challenges, researchers were able to identify an "overlooked" reduction in hardness in enamel specimens. The differences in the structure, chemical composition, and biological response to erosion in the presence of artificial saliva between enamel and ostrich eggshell could explain their distinct behaviors.

Challenges faced by undergraduate dental students during root canal treatment: a survey study / Desafios enfrentados por estudantes de graduação em odontologia durante o tratamento de canal radicular: um estudo de pesquisa

Introduction: root canal treatment is a challenging procedure often first encountered by undergraduate dental students, leading to various difficulties and mistakes. Objective: this study aimed to identify the specific difficulties encountered by undergraduate dental students during root canal treatment and the frequency of mistakes they committed in relation to these difficulties. Material and method: this study employed a cross-sectional survey design. A cohort of 60 third-year students completed a self-administered questionnaire consisting of 27 questions addressing various aspects of endodontic treatment and 11 key areas of root canal procedures. The response options for each question were based on a 4-point Likert scale. Data analysis was performed using Python programming language and heatmaps were created using the seaborn library to better understand the distribution of the data. Result: students encounter challenges in developing tactile sensation, accessory cone placement, and accurately reaching the apex during canal location. Dental schools should focus on improving students' tactile skills and methods to reach the apex to enhance the effectiveness of root canal treatment education. In contrast, students reported fewer mistakes in rubber dam application and safety measures during treatment. Dental educators should emphasize proper instrument use and safety precautions during root canal treatment. Interestingly, students did not perceive these areas as problematic despite committing mistakes. Conclusion: this study provides valuable insights into the challenges and mistakes encountered by undergraduate dental students during root canal treatment. Dental educators should address these issues to improve students' skills and techniques and provide optimal patient care.

Introdução: o tratamento endodôntico é um procedimento desafiador, frequentemente encontrado pela primeira vez por estudantes de odontologia, levando a diversas dificuldades e erros. Objetivo: este estudo teve como objetivo identificar as dificuldades específicas encontradas por estudantes de graduação em Odontologia durante o tratamento endodôntico e a frequência de erros cometidos por eles em relação a essas dificuldades. Material e método: este estudo empregou um desenho de pesquisa transversal. Um grupo de 60 estudantes do terceiro ano respondeu a um questionário autoaplicável composto por 27 perguntas abordando vários aspectos do tratamento endodôntico e 11 áreas-chave dos procedimentos de canal radicular. As opções de resposta para cada questão foram baseadas em uma escala Likert de 4 pontos. A análise dos dados foi realizada utilizando a linguagem de programação Python e mapas de calor foram criados utilizando a biblioteca seaborn para melhor compreender a distribuição dos dados. Resultado: os alunos encontram desafios no desenvolvimento da sensação tátil, na colocação do cone acessório e no alcance preciso do ápice durante a localização do canal. As escolas de odontologia devem se concentrar em melhorar as habilidades táteis e os métodos dos alunos para alcançar o ápice e aumentar a eficácia do ensino sobre tratamento de canal radicular. Em contrapartida, os estudantes relataram menos erros na aplicação do dique de borracha e nas medidas de segurança durante o tratamento. Os educadores odontológicos devem enfatizar o uso adequado dos instrumentos e as precauções de segurança durante o tratamento do canal radicular. Curiosamente, os alunos não consideraram estas áreas problemáticas, apesar de cometerem erros. Conclusão: este estudo fornece informações valiosas sobre os desafios e erros encontrados por estudantes de odontologia durante o tratamento endodôntico. Os educadores odontológicos devem abordar essas questões para melhorar as habilidades e técnicas dos alunos e fornecer o melhor atendimento ao paciente.

Interactive Crossword Puzzles as an Adjunct Tool in Teaching Undergraduate Dental Students.

Background: In the restorative dentistry module of the undergraduate dental program, dental students encounter many new terms and concepts in a short period of time. The provision of adequate learning support to reinforce key concepts can be challenging. Aim: The purpose of this study is to determine student perceptions of how effective interactive crossword puzzles are as adjunctive tools to enhance the learning of restorative dentistry. Methods: Students completed interactive crossword puzzles created by the authors, with a reward awarded to the first group of students who completed the puzzles successfully. The interactive crossword platform was programmed using the ReactJS framework and designed using Tailwind CSS. An evaluation of the student's perception of this educational method was conducted using textual feedback and Likert-scale questionnaires. Results: Students found the crossword puzzles engaging, meaningful, and successful as indicated by their favorable Likert scores and feedback. Written comments revealed student enthusiasm for and a desire to be exposed to more of these exercises. Conclusions: This work sheds light on the potential advantages of incorporating interactive crossword puzzles into the restorative dentistry course from a student's perspective. The crossword puzzles improved students' ability to review and reinforce concepts and terminology and proved to be meaningful and enjoyable. The web-based nature of the tool ensured good student responsiveness and engaged the entire class in an interactive, competitive setting. Application of the hint option, which offered a text of relevant reading material, helped students understand, retain more knowledge, and engage with course material more than they might have otherwise.

Perspective and practice of root caries management: a multicountry study - Part I.

BACKGROUND: Every effort needs to be made to better understand the current state of practice and trends relating to root caries management which will be of benefit to dentists universally in the practice of dentistry. AIM: This article presents a multicountry questionnaire survey of the current state of practice in the management of root caries among dentists in nine different countries to get a wider range of opinions and perspectives. METHODOLOGY: A questionnaire related to root surface caries was distributed among practicing dentists in nine different countries, namely the United Kingdom, Libya, Jordan, Saudi Arabia, Egypt, Brazil, India, Malaysia, and Iraq. Questionnaire responses were analyzed, and the results were compared among groups. RESULTS: The results showed statistically significant differences among dentists in most questionnaire aspects. Bleeding is the greatest obstacle facing dentists when restoring root surface lesions. Reported survival rates reflect uncertainty about the material and/or approach of choice in the management of root surface caries. CONCLUSION: This questionnaire survey revealed the current status of management of root surface caries in clinical practice in various countries. Substantial attention is required to bridge the knowledge gap and address the current void of uncertainty as relates to root caries management by providing a common ground for communication between dentists from all around the globe. In all, this work found a degree of consensus at the international level on what appears to work well among the dental practices surveyed and identified several issues with existing approaches that need to be addressed in future studies.

Perspective and practice of root caries management: A multicountry study - Part II: A deeper dive into risk factors.

BACKGROUND: The potential of an improved understanding to prevent and treat a complex oral condition such as root caries is important, given its correlation with multiple factors and the uncertainty surrounding the approach/material of choice. Deeper insights into risk factors may improve the quality of treatment and reduce the formation of root surface caries. AIM: The present work aims to gain knowledge about dentists' opinions and experiences on assessing the risk factor related to the development of root caries and to help identify any overlooked factors that may contribute to less efficacious clinical outcomes. METHODOLOGY: A questionnaire related to root surface caries was distributed among practicing dentists in nine different countries, namely the United Kingdom, Libya, Jordan, Saudi Arabia, Egypt, Brazil, India, Malaysia, and Iraq. Questionnaire responses were analyzed, and the results were compared among the groups. RESULTS: Dentists around the world ranked the oral hygiene status of patients as the most important factor in the development of root surface caries. Patients with poor oral hygiene, active periodontal disease, reduced salivary flow, and gingival recession are perceived to have a higher risk of developing new root surface caries. There is a greater focus on prevention in the UK and greater levels of untreated dental disease in other countries, especially those recovering from civil wars. CONCLUSION: This work identified some overlooked factors that may have contributed to the less efficacious clinical outcomes reported in the literature. It is hoped that this deep dive into risk factors coupled with the findings presented in Part I of this study will be used as a basis for a more comprehensive investigation into the management of patients with root surface caries.

Personality, learning styles and handedness: The use of the non-dominant hand in pre-clinical operative dentistry training.

AIM: This research was undertaken with the aim of using personality traits, learning styles and handedness to develop and evaluate a scale to measure a new concept in operative dentistry, symmetrisation. An initial hypothesis was proposed, stating that handedness, personality trait and learning style could be used to predict symmetrisation potential in the domain of operative dentistry. METHODS: Participants completed three questionnaires: the Edinburgh handedness inventory assessment; the Keirsey Temperament Sorter-II (KTS-II); and the learning style assessment (VARK). Then, participants prepared a cavity on an artificial third molar tooth in the traditional phantom head using their non-dominant hand. For evaluation and comparison purposes, Standard Tessellation Language images were obtained from prepared teeth using a CAD/CAM scanner and then aligned against a reference "unprepared" tooth image using a custom software developed by the authors based on the Iterative Closest Point algorithm. RESULTS: Extroverts, intuitive and participants characterised as relying on their feelings were more accurate compared to introverts, sensory and toughminded participants, respectively. Extroverts were faster to complete the task compared to introverts. Participants with a preference for read/writing learning style produced more errors than any of the other groups. Handedness, however, did not show any significant association with performance. CONCLUSIONS: It was concluded that both the KTS-II and the learning style assessment (VARK) questionnaires possess potential as useful measures of symmetrisation potential and the ability to use the non-dominant hand in operative dentistry, as well as platform for continuing research.

The effect of adding graphene oxide nanoplatelets to Portland cement: Potential for dental applications.

BACKGROUND: The potential of graphene-based materials to improve the physiomechanical properties of Portland cement-based materials without compromising biocompatibility is of interest to dental researchers and remains to be discovered. AIM: This study investigated the effects of adding graphene oxide nanoplatelets (GONPs) on the surface microhardness and biocompatibility of Portland cement. MATERIALS AND METHODS: Three prototype Portland cement powder formulations were prepared by adding 0, 1, and 3 wt % GONPs in powder form to Portland cement. Prototype cement specimens were in the form of disks, with a diameter of 10 mm and a thickness of 2 mm. In experiment 1, surface microhardness was measured using the through indenter viewing hardness tester, 20 surface hardness values were obtained from all specimens. In experiment 2, Balb/C 3T3 fibroblasts were cultured with the material disks and the viability of cells was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. STATISTICAL ANALYSIS: The data were analyzed using the analysis of variance followed by Dunnett test (α = 0.05) or Tukey test (α = 0.05). RESULTS: In response to material disks, the addition of 1 wt % GONPs had a proliferative effect on cells at day 3 and day 7 with a significant difference from the control. The addition of 3 wt % GONPs showed a remarkable increase in surface microhardness; however, it exhibited initial cytotoxicity. CONCLUSIONS: The addition of 1 wt % GONPs to Portland cement improved surface microhardness without compromising biocompatibility; therefore, it has a greater potential for dental applications. The results of this work give other researchers leads in future assessments of this prototype material.

Collection of extracted human teeth in decline: working knowledge and understanding of the Human Tissue Act by UK-registered dentists.

Introduction For many years, the dental profession has collected extracted human teeth for use in education and research. Since the enactment of the Human Tissue Act (HTA) in 2006, we have observed a fall in research outputs from the United Kingdom utilising extracted teeth for research.Aims To determine the working knowledge and understanding of the HTA of dentists in the UK who could potentially collect extracted teeth for use in teaching and research.Design A postal/online questionnaire.Materials and methods A printed questionnaire and pre-paid return envelope, which sought to assess both the knowledge and understanding of the participants concerning the HTA as it applied to the collection of extracted teeth, was mailed out to 500 UK-registered dentists. The potential participants were selected at random from the General Dental Council online registers.Results A total of 254 completed questionnaires were received (response rate = 50.8%). Prior to September 2006, 65.6% of respondents had collected teeth. After this, only 37.8% did so. This was statistically significant (P <0.001).Conclusions Confusion surrounded the collection and use of extracted teeth, which hampered dental education and research. To address this, there is a need for clarity on the legal issues.

Impact of Blended Learning on Dental Students' Performance and Satisfaction in Clinical Education.

The aim of this study was to evaluate the effectiveness of a blended learning model with a flipped classroom approach in a clinical dental education setting based on student performance and perceptions. Comparisons were made between blended learning and traditional methods for all fourth-year dental students in two consecutive cohorts in a conservative dentistry course at a dental school in Jordan. The 2016-17 cohort (control group) consisted of 364 students taught with conventional methods. The 2017-18 cohort (study group) consisted of 253 students taught with blended learning using a flipped classroom method. Performance measures were two exams (online and written), two assignments, inclinic quizzes, and clinical assessment. The study also assessed the number of posts made by students in the study group on an online discussion forum. The results showed that the study group students had significantly better performance on all assessments than the control group students. The students' overall grades in the blended learning cohort were an average 7.25 points higher than in the control cohort. Students who participated in the online forum also had better performance in the course: one participation correlated with 0.697 standard deviations higher score. Overall, students' perceptions were positive and supported the adoption of a blended learning model in the course. These results showing improved student performance provide support for blended learning and use of an online discussion forum.

Biocompatibility evaluation of Jordanian Portland cement for potential future dental application.

BACKGROUND: The demand for novel Portland cement (PC)-based formulations to be used in dental applications is ever increasing in viewing the foregoing knowledge on the favorable effects of these formulations on cellular proliferation and healing, leading to treatment success. AIM: This study investigated the effect of white and gray mineral trioxide aggregate (W-MTA and G-MTA) and white and gray Jordanian PC (W-PC and G-PC) in their raw state on the viability of Balb/C 3T3 fibroblasts using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MATERIALS AND METHODS: Materials were prepared in the form of disks, with a diameter of 5 mm and a thickness of 2 mm. In the first experiment, Balb/C 3T3 fibroblasts were cultured with the material disks using culture plate inserts. In the second experiment, material elutes were added to cultured cells. The elutes were prepared by adding 2 ml serum-free media to 10 disks of each material and then incubated at 37°C for different time intervals. Material elutes were analyzed using ion chromatography for traces of calcium. The data were analyzed using analysis of variance followed by Dunnett test (α = 0.05) or Tukey test (α = 0.05). RESULTS: In response to material disks, G-PC had a proliferative effect on cells at day 1 and day 2 with a significant difference from the control at day 1. G-MTA reduced cell viability with a significant difference from the control level at day 2. Elutes of PC showed biocompatible and even proliferative effects on Balb/C 3T3 fibroblasts. Calcium ions were found to leach continuously over the measurement period for all the materials tested in this work. CONCLUSION: Jordanian PC in its raw state was found to be biocompatible, and the results of this work give promise of its wider use as a base for further development to improve the physiochemical and mechanical properties of the material.

Debate as an Adjunct Tool in Teaching Undergraduate Dental Students.

This work is an attempt to explore the potential of a new educational method that integrates debate as a teaching tool. This new teaching method was implemented into a single academic semester of an undergraduate bachelor of dentistry program. We sought to combine knowledge delivery with high-level debate between student debaters, and with the active participation of the audience who were themselves students. The teaching method comprised of three elements namely debates, reply speeches, and policy papers. Debating followed the World School Debate Championship (WSDC) format. Debate evaluation involved five main categories; argument, rebuttal, style, definition and strategy, and points of information (POIs). Student perception towards this educational method was evaluated using a Likert-scale questionnaire. Students gained valuable knowledge from the experience as reflected by the favorable Likert outcome scores. This work sheds light on the potential advantages of utilizing debate as a teaching tool from a student's perspective. Implementing debate in teaching improved students' ability to search and appraise scientific papers and proved to be meaningful and enjoyable. The carefully tailored 10-week format ensured good student responsiveness and engaged the entire class in an interactive, participatory setup. This educational method proved to be very effective in evidence-based dentistry teaching by promoting a deeper approach to learning that can help students to learn meaningfully and enhance their critical thinking skills.

In vitro simulation of erosive challenges to human enamel using a novel artificial mouth.

This in vitro work reports upon the design, build and operation of an artificial environment (Saltus) that sought to simulate the process of in vivo dental erosion upon human enamel. A novel testing environment, housed 8 erosion testing substrate specimens, that on separate occasions were subject to 4 different experimental diets, of increasing erosive challenge, simulating the consumption of an acidic beverage. Each set of specimens was subjected to one of the experimental diets only. These were liquid only and administered the test beverage over a standardized range of volumes and durations. Flow of both artificial unstimulated and stimulated saliva was maintained throughout and the effects upon the substrates were measured by profilometry, surface microhardness determination and chemical analysis of the saliva and beverage mixture for traces of Calcium and Phosphate ions. The overall trend of surface hardness reduction, depth of surface loss and ion loss across the diets increased in proportion to the severity of insult. Accepting the limitations of this study Saltus appeared to perform well as an environment in which to simulate and assess dental erosion using parameters defined by previous in vivo observations of human drinking behaviour. The authors however acknowledge that in vitro testing can never replicate fully the in vivo situation.