A comparative evaluation of calcium ion release and pH change using calcium hydroxide nanoparticles as intracanal medicament with different vehicles - An in vitro study.

Context: Nano-calcium hydroxide (NCH) has been proven to have several advantages over normal calcium hydroxide, supporting in its possible use as an intracanal medicament. Aim: The aim is to evaluate and compare calcium ion release and pH change using NCH with different vehicles as intracanal medicament. Subjects and Methods: Sixty freshly extracted premolars were decoronated at the cementoenamel junction level and the length was standardized. Canals were enlarged to F3 size using protaper rotary system. The samples were divided into three groups (n = 20), namely NCH + distilled water (Group 1), NCH + propylene glycol (Group 2), and NCH + chitosan (CT) (Group 3). Each sample was suspended in 6 ml of distilled water using silicone putty with only the apical third of the roots immersed. The pH and calcium ions were assessed at 24 h, 7 days, 15 days, and 30 days using a pH meter and ultraviolet spectrophotometer, respectively. Statistical Analysis: Comparison of mean calcium release and pH change was made using Kruskal-Wallis ANOVA with post-hoc Dunn's test. The level of significance was set at 5%. Results: A significant difference was seen in the calcium ion release and pH change among the three groups at 24 h, 7 days, 15 days, and 30 days. Conclusions: NCH mixed with propylene glycol showed alkaline pH and adequate release of calcium ions till 30 days. NCH mixed with CT exhibited a high pH at the end of 30 days. Both combinations proved their efficacy as intracanal medicaments.

Evaluation of Dental Interns' Perception and Self-Confidence Levels Regarding Endodontic Treatment"- A Questionnaire Study

ABSTRACT Objective: To evaluate the perception and self-confidence of Dental interns regarding endodontic treatment performed on patients. Material and Methods: A total of 111 dental interns from 5 different educational institutes of a state in South India participated in a questionnaire-based survey. The questionnaire consisted of 12 questions related to root canal procedures performed on patients. Analysis was done using SPSS version 17.0. Results: Sixty-five interns (59%) performed less than 10 root canal treatments on patients during the course of the internship. Twenty-eight interns (25% of the intern population) took up more than 10 root canal treatment cases, whereas only 18 interns (16%) did not perform the treatment on patients and answered the questionnaire based on their experience with extracted teeth model work. Only five interns out of 111 were 'Very confident' and 22 were 'Confident' in performing the root canal treatment. Conclusion: The present study indicates that the self-perceived confidence level among dental interns can affect their clinical performance. It also recommends additional hands-on workshops, problem-based learning and clinical guidance for the dental interns to become more confident with the root canal procedure.

Comparative Evaluation of Corneal Storage Medias Used as Tooth Avulsion Medias in Maintaining the Viability of Periodontal Ligament Cells Using the Cell Counting Kit-8 Assay.

Purpose: The prime factor in determining the success of reimplantation of an avulsed tooth is the maintenance of the viability of periodontal ligament fibroblast cells (PDFC). This study aims to evaluate and compare Mc Carey Kaufman media (MK), Cornisol, Dulbecco's Modified Eagles Medium (DMEM), Hanks Balanced Salt Solution (HBSS) and distilled water in preserving the viability of the PDFC using the Cell Counting Kit-8 assay (CCK-8). Methods: Cryopreserved PDFC were suspended in DMEM and incubated in CO2 incubator at 370C with 95% humidity and 5% CO2 for attachment. Once cells attained 80% confluence, they were trypsinised and passed into T-25 culture flasks to expand the culture population. Cells from passage 5 were pooled for experimentation. Trypan blue exclusion test was performed before each experiment to measure cell viability and batches showing more than 95% viability were used in the experiment. The viable PDFC with 1×105 were seeded in 96 well plates and incubated in CO2 incubator at 370C, 95% humidity and 5% CO2 for 24 hours to allow cell attachment. A 100µL of the experimental media were added in the wells and the cells were exposed for 1, 24 and 48 hours respectively. The viability was determined using the CCK-8. Experiment was performed in triplicates and data was subjected to statistical analysis. Results: Statistical analysis was performed using repeated measure ANOVA, ANOVA, and post-hoc Bonferroni test with the significance level p<0.05. The values are as follows: MK (1.3146 ±0.0588, 1.9012±0.0511, 2.0723±0.1211) > Cornisol (1.2399±0.0548, 1.9596±0.0652, 1.9592±0.1361) >DMEM (1.1914±0.0691, 1.8479±0.0116, 2.0718±0.0795) > HBSS (0.3665±0.0814, 0.0184±0.0010, 0.0248±0.0042) >distilled water (0.0122±0.0033, 0.0225±0.0085, 0.0104±0.0008) at 1 hour, 24 hours and 48 hours respectively. MK >Cornisol>DMEM>HBSS>distilled water. Conclusion: It can be concluded that the corneal preservation solutions showed promising results in preserving periodontal ligament cell viability for extended time periods.

Work-life balance amongst dental professionals during the COVID-19 pandemic-A structural equation modelling approach.

BACKGROUND: The Coronavirus disease (COVID-19) outbreak in 2019, has shocked the entire world. As an effort to control the disease spread, the Indian government declared a nationwide lockdown on March 25th, 2020. As dental treatment was considered high risk in the spread of COVID-19, dentistry became one of the most vulnerable professions during this time. Dental professionals had to face job layoffs, salary cuts in professional colleges, closure of private clinics resulting in huge psychological, moral, and financial crises. Studies during the previous and present pandemics have shown mental issues among health care workers necessitating institutional reforms, along with early care and support. A balance in the work-life amongst professionals is the key to better efficiency and, was majorly affected during the COVID-19 pandemic lockdown due to sudden unexpected changes. Hence this study was conducted to understand the changes they underwent both at home and professional front with a hypothesis that physical and mental health, activities, relationship status, and workplace influence the work-life balance. METHODS: A pre-validated questionnaire survey was done on dentists across India. Structural Equation Modelling and path analysis were applied to the data collected. RESULTS: The results of the study supported the hypothesis that factors like physical and mental health, activities, relationship status, and workplace influenced the work-life balance directly. A significant imbalance was seen amongst the female dentists. CONCLUSION: The present study proved the unpreparedness among dental professionals. Hence an evolutionary phase in every field with better working protocols, robust mental health support, and a focus on strategies to face future such emergencies is required.

Comparison of regulatory framework of clinical trial with genetically modified organism-containing vaccines in the Europe, Australia, and Switzerland.

New vaccines production and manufacture have revolutionized by recombinant technology. Various regulatory associations are engaged with the appraisal of a clinical trial with genetically modified organisms. At present safe, effective vaccines are needed in order to control the various emerging diseases which are a major cause of mortality. In reality, most vaccines raise biosafety worries with respect to human wellbeing. "Federal Office for Environment" is the competent authority for environmental risk assessments in Switzerland. Gene Technology Act 2000 is the fundamental direction that provides the necessary information to carry the clinical trials with genetically modified organism-containing vaccines. In addition, regulatory framework for "clinical trial with genetically modified organisms-containing vaccines" is stringent and partially harmonized in Switzerland, the European Union and Australia. In this study, we mainly concerned with regulatory aspects of "clinical trial with genetically modified organism" containing vaccine in three regions. This review includes various aspects like ethics, guidelines related to clinical trials of vaccines with genetically modified organisms.

Survival of human periodontal ligament fibroblast cells in Cornisol and HBSS for transportation of avulsed teeth: a comparative ex vivo study.

OBJECTIVE: Viability of periodontal ligament fibroblast cells (PDFC) is one of the key factors in determining the success of replantation of avulsed teeth. Extra-oral time and transport media are closely related to the same. The present study aims to evaluate and compare the efficiency of Cornisol, Hank's balanced salt solution (HBSS) and normal saline in preserving the viability of PDFC. MATERIALS AND METHODS: The human PDFC were isolated from primary culture from freshly extracted human premolars. Effect of Cornisol, HBSS and normal saline on viability of isolated PDFC was assessed using standard MTT assay. The cells were exposed to the experimental solutions (Cornisol/HBSS/normal saline) for varying time points (30 min, 1 h, 24 h, 48 h and 96 h) and viability was determined by colorimetric MTT method by quantifying the amount of formazan crystal formed (optical density). Experiment was performed in triplicates and the data were subjected to statistical analysis. RESULTS: Statistical analysis was performed using the Kruskal-Wallis ANOVA with post hoc Bonferroni's test with a significance level of p value ≤.05. Cornisol ≥ HBSS > saline. CONCLUSION: Cornisol can be used as a storage media for avulsed teeth and is significantly more effective than HBSS in maintaining the periodontal ligament cell viability at tested time intervals.

Numerical Three-dimensional Finite Element Modeling of Cavity Shape and Optimal Material Selection by Analysis of Stress Distribution on Class V Cavities of Mandibular Premolars.

AIM: Adhesive restoration does not depend primarily on the configuration of the shape of the cavity. Under varying loading conditions, it is essential to know the stress concentration and load transfer mechanism for distinct cavity shapes. The aim of this study was to evaluate and compare the biomechanical characteristics of various cavity shapes, namely oval, elliptical, trapezoidal, and rectangular shapes of class V cavities on mandibular premolars restored with amalgam, glass ionomer cement, and Cention N using three-dimensional (3D) finite element analysis. MATERIALS AND METHODS: A 3D prototype of a mandibular premolar was generated by Digital Imaging and Communications in Medicine (DICOM) images obtained from the cone beam computed tomography and imported to 3D modeling software tool, SpaceClaim. The four distinct load magnitudes of 100, 150, 200, and 250N were applied as a pressure load perpendicular to the lingual plane of the lingual cusp of the occlusal surface (normal load) and at 45° to same (oblique load). The stress distribution patterns and the maximum von Mises stresses were analyzed and compared. RESULTS: The occlusal stresses were distributed from the force loading point in an approximate actinomorphic pattern, and when the force load was close to the margin, the stress was much greater. CONCLUSION: Ovoid cavity showed lesser stress concentration and deformation for each of the tested restorative material.

Comparative Evaluation of Fluoride Release From Two Different Glass Ionomer Cement and a Novel Alkasite Restorative Material - An in Vitro Study

Abstract Objective: To compare the fluoride release from Conventional Glass Ionomer Cement (GIC), Resin Modified GIC (RMGIC), and Cention N Alkasite Material. Material and Methods: Forty- five disc-shaped specimens of three different restorative materials (Conventional GIC, RMGIC, and Alkasite material) were made and divided into 3 groups (n=15). Fluoride release was evaluated at the end of Day 1, 7, 14, and Day 28 using fluoride ion-selective electrode. Intergroup and Intra-group analysis was done using One-way ANOVA with a Post-hoc test. A p-value of <0.05 was considered statistically significant. Results: Cention showed more fluoride release (in parts per million) than GIC and RMGIC at increased time duration. However, at the end of day 1, there was lesser fluoride release with Cention, as compared with the other groups. Conclusion: The new Alkasite restorative material showed promising results in terms of fluoride release and is better than GIC and RMGIC at increased time duration.

Effect of Thermocycling on the Colour Stability of Aesthetic Restorative Materials: An in-vitro Spectrophotometric Analysis

Abstract Objective: To compare the color stability of Cention N, Fuji IX GP Extra, and Fuji IX GP after thermocycling. Material and Methods: Ten discs of each material of dimension 10 x 1 mm were prepared using a split mold. The preparations of the specimens were done according to the powder/liquid ratio as recommended by the manufacturers [4.6:1, 3.4:1 and 3.6:1 for the groups I, II, and III, respectively]. After setting, the samples were retrieved, and the thickness of each specimen was measured using a micrometer at five different locations. The specimens with variations in thickness, porosity or cracks were discarded and thus not included in the study. The selected specimens were stored in distilled water for 24 hours prior to testing. The prepared specimens were thermocycled at 5°C and 55°C, with a dwell time of 15 seconds for 250 or 500 cycles. Subsequently, the color parameters of the discs were measured using a spectrophotometer. The data were analyzed using two way ANOVA test, and a p-value <0.001 was considered. Results: Thermocycling resulted in changes in the color of both Glass Ionomer cement and Cention N (p<0.001). Among the materials tested, Cention N showed superior color stability. Conclusion: Cention N exhibited better color stability compared to Glass ionomer cements.

Evaluation and Comparison of Stress Distribution in Restored Cervical Lesions of Mandibular Premolars: Three-dimensional Finite Element Analysis.

OBJECTIVES: Restorative materials are used in the treatment of cervical lesions and restoration of the dental tooth. The objective of this study was to assess the suitability of the three commonly used restorative materials by dentists and the evaluation of stress distribution and deformation using Von Mises stress in cervical lesions of mandibular premolars under varying loading condition. MATERIALS AND METHODS: A computerized model of restored class V cavity of mandibular premolar tooth was created using three dimensional modeling software SpaceClaim. It was subjected to occlusal pressure load of 100, 150, 200 and 250MPa at right angle to buccal cusp and was analyzed for stress distribution and deformation in different restorative materials using Finite Element analysis, ANSYS Workbench. RESULTS: The analysis carried on the class V restored tooth from biomechanical point of view indicates that restorative material glass-ionomer cement exhibited better bonding with the tooth structure using ionic bonds with the calcium ion present in the tooth structure. The variation of 8%-9% of stress concentration is observed in cavity region across varied pressure loads with glass-ionomer cement to Cention N. CONCLUSION: Glass-ionomer cement had showed better results than amalgam in terms of biomechanical property which is in agreement with the clinical findings. The stress values of Cention N were comparable to that of glass-ionomer cement.

Effect of calcium hydroxide and triple antibiotic paste as intracanal medicaments on the incidence of inter-appointment flare-up in diabetic patients: An in vivo study.

AIM: To evaluate and compare the effect of antibacterial intracanal medicaments on inter-appointment flare-up in diabetic patients. MATERIALS AND METHODS: Fifty diabetic patients requiring root canal treatment were assigned into groups I, II, and III. In group I, no intracanal medicament was placed. In groups II and III, calcium hydroxide and triple antibiotic pastes were placed as intracanal medicaments, respectively. Patients were instructed to record their pain on days 1, 2, 3, 7, and 14. Inter-appointment flare-up was evaluated using verbal rating scale (VRS). RESULTS: Overall incidence of inter-appointment flare-up among diabetic patients was found to be 16%. In group I, 50% of the patients and in group II, 15% of the patients developed inter-appointment flare-up. However, no patients in group III developed inter-appointment flare-up. The comparison of these results was found to be statistically significant (P = 0.002; χ(2) = 12.426). However, with respect to intergroup comparison, only the difference between groups I and III was found to be statistically significant (P = 0.002; χ(2) = 12.00). CONCLUSIONS: Calcium hydroxide and triple antibiotic paste are effective for managing inter-appointment flare-ups in diabetic patients. Triple antibiotic paste is more effective than calcium hydroxide in preventing the occurrence of flare-up in diabetic patients.