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In this work, Cobalt (0-10) % doped MgO nanoparticles are prepared for magnetic and optical studies. X-ray diffraction studies show the particle size increases from 3.10 nm to 9.50 nm with increasing Cobalt concentration in MgO samples. The secondary phases are observed beyond 5% Cobalt in the host MgO which indicates the solubility limit of dopant in this material. SEM analysis further reconfirms the purity and spherical morphology of nanoparticles in all samples. Its result also reveals that the smallest particles have the largest oxygen vacancy concentration as compared to other samples. The dopant and size-induced effects are observed for electronic absorption spectra and bandgap of the samples. UV-visible absorption spectra show a quantum confinement effect as the optical band gap decreases with the increase of the particle size. The optical band gap of the nanoparticles ranges from 4.68 eV to 3.15 eV which is very less in comparison with the bulk MgO band gap up to 7.2eV. Vibrating sample magnetometer studies at room temperature clearly show the ferromagnetic behavior for pure MgO nanoparticles in contrast with the paramagnetic behavior for other samples. It is suggested that the presence of the ferromagnetic behavior in pure MgO nanoparticles are due to the presence of oxygen vacancies.

Effects of Cu addition (0-5)% in ZnO are studied for structural and optical properties. The structural, photoluminescence properties and vibrational modes are strongly influenced with the Cu incorporation. Detailed investigations of the structural features of Cu doped ZnO nanostructures are reported. Our results show the systematic decrease in crystallite size (50.40 - 37.56 nm), lattice strain (1.82 - 1.49 micro), lattice stress (216.33 - 177.64 MPa) and energy density (196.78 - 132.69 KJ/m3) in the limit of small dopant concentration (0 < Cu ? 0.02). Decreasing trends are attributed to the smaller ionic size of Cu in comparison of Zn. Beyond Cu= 0.02 an increasing trend was noticed in crystallite size (41.67 - 70.67 nm), lattice strain (1.90 – 3.11 micro), lattice stress (226.32 – 369.35 MPa) and energy density (215.40 – 573.67KJ/m3. This increase in structural parameters is attributed to segregation of secondary phases for Cu content increase beyond 0.02. Two prominent regions in PL spectra were observed and the deconvoulution of these regions show a strong correlation with the structural changes observed within the limit of high and low dopant concentration. The FTIR spectra show shift of Zn-O vibrational mode toward higher frequency with increasing Cu concentration.

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The aim of this study was to present a concise summary of the oral health policies and oral healthcare schemes for older adult populations in a number of selected countries around the world. In this paper, the current and planned national/regional oral health policies and oral healthcare schemes of nine countries (Australia, Brazil, China including Hong Kong, India, Japan, Switzerland, Thailand, the United Kingdom, and the United States) are reported. Barriers and challenges in oral health promotion in terms of devising oral health policies, implementing oral health schemes, and educating the future dental workforce are discussed. In response to the aging of population, individual countries have initiated or reformed their healthcare systems and developed innovative approaches to deliver oral health services for older adults. There is a global shortage of dentists trained in geriatric dentistry. In many countries, geriatric dentistry is not formally recognized as a specialty. Education and training in geriatric dentistry is needed to produce responsive and competent dental professionals to serve the increasing number of older adults. It is expected that oral health policies and oral healthcare services will be changing and reforming in the coming decades to tackle the enduring oral health challenges of aging societies worldwide.

A simple experimental setup based on a polarizing optical technique is designed to find the thickness of free standing thin film of Biphenyl (E7). Monochromatic light is passed through a liquid crystal thin film in two different modes of placement. In each mode approximately 10 mg of Biphenyl is used. The films of varying area were used in this study. The thin films were highly stable and could survive more than one day. The intensity of transmitted monochromatic radiation is measured using this technique by placing thin film in horizontal and vertical modes. Using Beer-Lambert’s Law the thickness of thin film is also measured using polarizing optical technique. In both the modes (horizontal and vertical) different behaviors of thickness of thin film are observed..

Background: Oral hygiene maintenance is crucial for prevention of various oral diseases. Oral hygiene practices across the country vary largely and people in peri-urban and rural areas use traditional methods of oral hygiene like powders, bark, oil and salt etc. Their effect on oral soft and hard tissues need to be studied to understand their beneficial and/ or harmful effects on maintenance of oral hygiene and prevention or causation of oral diseases. Objectives: This study aimed to assess the plaque-cleaning efficacy, gingival bleeding, recession and tooth wear with different traditional oral hygiene methods as compared to use of toothpaste-toothbrush, the most accepted method of oral hygiene practice. Study Design: Hospital based cross sectional analytical study. Results: Total 1062 traditional oral hygiene method users were compared with same number of toothpaste-brush users. The maximum number in the former group used tooth powder (76%) as compared to other indigenous methods, such as use of bark of trees etc and out of tooth powder users; almost 75% reported using red toothpowder. The plaque scores and gingival bleeding & recession were found to be more in traditional oral hygiene method users. The toothwear was also more severe among the toothpowder users. Conclusions: Traditional methods were found to be inferior in plaque control as was documented by increased bleeding and gingival recession. Its effect on hard tissues of teeth was very damaging with higher tooth wear scores on all surfaces.

Background: Age estimation in living individuals is imperative to amicably settle civil and criminal disputes. A biochemical method based on amino acid racemization was evaluated for age estimation of living Indian individuals. Design: Caries-free maxillary/mandibular premolar teeth (n = 90) were collected from participants with age proof documents and divided into predefined nine age groups. Materials and Methods: Dentine biopsy from the labial aspect of the tooth crown was taken with an indigenously developed microtrephine. The samples were processed and subjected to gas chromatography. Dextrorotatory:levorotatory ratios were calculated, and a regression equation was formulated. Results: Across all age groups, an error of 0 ± 4 years between protein racemization age and chronological age was observed. Conclusion: Aspartic acid racemization from dentine biopsy samples could be a viable and accurate technique for age estimation of living individuals who have attained a state of skeletal maturity.

Magnesium oxide (MgO) nanoparticles are synthesized by a simple coprecipitation method. XRD studies reveal that nanoparticles are predominantly (100) textured with an average crystallite size of 19 nm.The relative peak intensities for (100) and (110) textured grains i.e., I(100)/I(110) is found to be ~ 2. Scanning electron microscope (SEM) pictures of our samples indicate that our synthesized nanoparticles are spherically shaped. Due to excellent electron tunneling features of (100) textured MgO nanoparticles, our synthesis method is suitable for cost effective and simple synthesis of pure MgO nanoparticles for applications involving electron tunneling.

Aims and Objectives: The study aims at determining pulp response of two high fluoride releasing materials silver diamine fluoride (SDF) and Type VII glass ionomer cement (GIC) when used as indirect pulp treatment (IPT) materials. Materials and Methods: Deep Class V cavities were made on four first premolars indicated for extraction for orthodontic reasons. SDF, Type VII GIC, and calcium hydroxide base are given in three premolars, and one is kept control. Premolars were extracted 6 weeks after the procedure and subjected to histopathological examination to determine the pulp response. The results were analyzed using Chi-square test. Results: No inflammatory changes were observed in any of the groups. Significantly more number of specimens in SDF and Type VII GIC groups showed tertiary dentin deposition (TDD) when compared to control group. No significant difference was seen in TDD when intergroup comparison was made. Odontoblasts were seen as short cuboidal cells with dense basophilic nucleus in SDF and Type VII GIC group. Conclusion: The study demonstrated TDD inducing ability of SDF and Type VII GIC and also established the biocompatibility when used as IPT materials.

Cobalt (Co) doped magnesium hydroxide Mg(OH)2 nanoparticles are synthesized by a surfactant-free co-participation method. Scanning electron microscopy (SEM) images show nanometer size Mg(OH)2 particles in spherically shaped particle-like morphology. Synthesis of these Mg(OH)2 nanocrystals involves the formation of monomeric MgOH[Formula: see text] ions as the precursor for the Mg(OH)2 nuclei which finally evolves in spherical particle-like morphology. X-ray diffraction (XRD) confirms the hexagonal crystal structure of the samples. With increasing Co concentration, the absorption spectra of the samples show narrowing of the bandgap from 5.47 eV (for pure Mg(OH2)) to 5.26 eV (for 10% Co-doped Mg(OH2)) effect is attributed to changes in the interaction potentials between Co and the host Mg(OH)2 lattice due to dopant-induced lattice distortion and the presence of a mixed valance Co[Formula: see text]/Co[Formula: see text] state.

Purpose The aim of the present study was to compare the marginal fidelity and surface roughness of porcelain veneers fabricated by the refractory die and pressing techniques under in vivo conditions. Materials and Methods A total of 72 veneers were prepared for anterior teeth in 12 participants. Veneers on anterior teeth in the first and second quadrants were fabricated using refractory die (group I) and pressing techniques (group II), respectively. Surface roughness was evaluated using a profilometer in three areas (cervical, mesio-incisal, disto-incisal) for each veneer. Marginal adaptation of all the veneers (N = 36/group) was evaluated at each margin (cervical, incisal, mesial, and distal) at 7 days and at 3 months after cementation under a scanning electron microscope (SEM) at 200× magnification. Results The mean surface roughness of veneers in cervical, mesio-incisal, and disto-incisal areas was 0.41 ± 0.25, 0.33 ± 0.14, and 0.32 ± 0.14 μm, respectively, for group I; and 0.31 ± 0.11, 0.36 ± 0.18, and 0.29 ± 0.11 μm, respectively, for group II. Intra- and intergroup comparisons showed no statistically significant values for all areas (p > 0.05). In 144 margins evaluated for each group, a visible gap was present in 15 (10.4%) and 18 (12.5%) recordings at 7 days for groups I and II, respectively. They increased to 19 (13.1%) and 20 (13.8%) after 3 months. These gaps were further broken down into percent distribution of total recordings at the cervical, incisal, mesial, and distal margins. Intragroup comparison was made using the Cochrane test. The chi-square test and Fisher's exact test were used for intergroup comparison of margins, revealing no statistical difference (p > 0.05) Conclusion Within the limitations of the study, the surface roughness and marginal fidelity of porcelain veneers fabricated by refractory die technique and pressing technique were comparable.

Loss of pulp vitality in an immature permanent tooth arrests root development. This leads to tooth with open apex and weak lateral dentinal walls. Management of such necrotic teeth with immature roots poses several treatment challenges. The documented study was performed to evaluate and compare apexogenesis induced by revascularization, with and without platelet rich plasma (PRP) in non-vital, immature anterior teeth. Three patients having bilateral, non-vital, immature maxillary central incisors with apical periodontitis were recruited after institutional ethical clearance. Subsequent to chemo-mechanical preparation, revascularization with and without PRP was randomly induced in either of the tooth. The cases were followed-up clinically and radiographically at 6 and 12 months. There was a marked difference in periapical healing, apical closure and dentinal wall thickening of teeth treated by revascularization with PRP.

Introduction This study was conducted to evaluate and compare maturogenesis induced by revascularization with and without platelet-rich plasma (PRP). Methods Twenty patients with nonvital, immature anterior teeth were randomly categorized into 2 groups. Subsequent to chemomechanical preparation, revascularization with and without PRP carried on a collagen sponge was induced in groups 1 and 2, respectively. The cases were followed up clinically and radiographically at 6- and 12-month intervals. Results Clinically, all cases were asymptomatic with complete resolution of signs and symptoms. Radiographically, there was a marked difference in periapical healing, apical closure, and dentinal wall thickening in group 2 in comparison with group 1. However, root lengthening was comparable for both of the procedures. Conclusions Revascularization is a conservative and an effective method for inducing maturogenesis in nonvital, immature teeth. Supplementations with PRP can potentially improve the desired biological outcome of this regenerative technique.

Aim: This study aims to compare the periapical healing of teeth with asymptomatic apical periodontitis treated either by conventional apical preparation (CAP) or apical clearing technique (ACT). Materials and Methods: Twenty subjects with bilateral nonvital similar teeth exhibiting comparable periapical index (PAI) score were enrolled and randomly allocated. Group I (CAP, n = 20): Apical preparation three sizes greater (master apical file [MAF]) than the first binding file at the established working length. Group II (ACT, n = 20): Apical preparation three sizes greater than the MAF that was followed by dry reaming. Root canal therapy was accomplished in single-visit for all the teeth. They were pursued radiographically at 3, 6, 9 and 12 months. Pre- and post-treatment PAI scores were compared. To ascertain the proportion of healed teeth between the two groups, McNemar Chi-square test was applied. Results: At 3, 6, and 9 months’ time interval the proportion of healed teeth for Group II (ACT) was greater in comparison to Group I (CAP) (P < 0.05). However, at 12 months follow-up period this difference was not significant (P = 0.08). Conclusion: ACT enhanced the healing kinetics. However, the long-term (12 months) radiographic outcome was similar for either technique.

Introduction: Prevention of oral diseases can be achieved by preventive measures. There is an educational component associated to the preventive aspect. Health education is a cornerstone to the success of a preventive programme. Health education has always been regarded as a primary tool in imparting awareness, bringing changes in healthy behaviors and improved life. Aim: To assess the effectiveness of an Educational Video in improving oral health knowledge of subjects in a hospital setting. Methodology: The study was conducted in Outpatient Department, CDER, AIIMS. This was a cross sectional interventional study. In the present study a total of 109 subjects were considered those who completed pre and post intervention questionnaire. In order to assess baseline oral health knowledge, a-14 itemed questionnaire was specially designed, based on the contents of video and was pre-tested on 10 patients. Pre-intervention knowledge was assessed and then the 30-minute video was shown. Following this, post-exposure knowledge was assessed using the same questionnaire. Change in the knowledge score amongst the subjects was assessed pre and post-intervention (showing the video film). Results: Paired t- test was used to analyze the data. Pre-intervention mean knowledge score was 9.49±2.09 which increased to 11.55±1.60 post-intervention; the difference was statistically significant (P < 0.001). Conclusions: It was found that increase in knowledge score was statistically significant after exposure to an educational video film in a hospital setting. Incorporation of video in imparting oral health education can be an effective tool in improving oral health knowledge, which can impact the oral health behavior of people and community.

Statement of Problem: Change in color and loss of marginal adaptation of tooth colored restorative materials is not acceptable. Bleaching is commonly used for treating discolored teeth. However, the literature is scanty regarding its effect on color and marginal adaptation of direct and indirect composite laminate veneers (CLVs) under in vivo conditions. Purpose: Purpose of the study was to determine the effect of bleaching on color change and marginal adaptation of direct and indirect CLVs over a period of time when exposed to the oral environment. Materials and Methods: For this purpose, a total of 14 subjects irrespective of age and sex indicated for CLV restorations on maxillary anterior teeth were selected following the inclusion and exclusion criteria. For each subject, indirect CLVs were fabricated and looted in the first quadrant (Group 1) and direct CLV′s (Group 2), were given in the second quadrant. Color change was assessed clinically using intra-oral digital spectrophotometer and marginal adaptation was assessed on epoxy resin replica of the tooth-restoration interface under scanning electron microscope. After 6 months, the subjects underwent a home bleaching regimen for 14 days using 10% carbamide peroxide. The assessment of color change and marginal adaptation was done at 6 months after veneering (0-180 days), immediately after the bleaching regimen (0-194 days) and 3 months after the bleaching regimen (0-284 days). Results: The difference in median color change (ΔE) between the groups was tested using Wilcoxon rank sum test while the median color change with time within the groups was tested using Wilcoxon signed rank test. The difference in the rates of marginal adaptation was tested between the groups using Chi-square/Fisher′s exact test. Bleaching led to statistically significant color change at cervical (CE), middle and incisal (IE) regions when direct and indirect composites were compared (P < 0.05). During intra-group comparison, direct CLV′s showed significant color change at CE and IE regions when ΔE was compared at 180 days and 284 days (CE 10 vs. CE 30, P = 0.008, IE 10 vs. IE 30, P = 0.003). No significant differences were found when within group comparison was made for indirect laminates. Intergroup comparison between the groups showed significant difference in marginal adaptation at CE margin at all-time points (at baseline, P = 0.005; at 180 days, P = 0.007; 194 days, P = 0.025; at 284 days, P = 0.067). Conclusion: After bleaching, indirect CLVs performed better in terms of color stability whereas direct CLVs performed better in terms of marginal adaptation. Clinical Significance: Indirect composites should be preferred to direct composites as veneering materials as they have better color stability. Special attention should be given to their marginal adaptation especially in the CE region. Bleaching should be avoided in patients with composite restorations in the mouth.

To determine the effect of prosthesis need on nutritional status and oral health-related quality of life (OHrQoL) in elderly and to check the disparity between prosthesis need and prosthesis want in the Indian elderly.METHODS:A total of 946 geriatric participants reporting to a geriatric medicine clinic were recruited in the study. Mini-nutritional assessment (MNA), geriatric oral health assessment (GOHAI) indices, prosthesis need according to WHO criteria, and prosthesis want was recorded along with age, gender, socioeconomic status and posterior occluding pair.RESULTS:Significant associations exist between prosthesis need and age (p = 0.005), MNA (p = 0.006) and GOHAI (p = 0.000). Prosthesis demand too was influenced by age (p = 0.004), posterior occluding pairs (p = 0.000), MNA (p = 0.012) and GOHAI (p = 0.000). GOHAI was negatively correlated with upper (r = -0.445) and lower prosthesis need (r = -0.460). Participants with some prosthesis need had significantly lower MNA and GOHAI scores as compared to those with no prosthesis need. Though prosthesis need was high (79.7 %), demand was low (39.3 %).CONCLUSION:Prosthesis need affects nutritional status and OHrQoL in elderly, and a wide gap exists between need and want of prosthesis.

Aim : Indirect pulp capping (IPC) preserves the pulp vitality by disinfecting and remineralizing remaining carious dentin. In the present study, glass ionomer (GC, FUJI VII) and silver diamine fluoride (SDF) were tested and compared to calcium hydroxide for their antimicrobial efficacy and remineralizing potential. Materials and Methods : Dentin disks prepared from 45 freshly extracted first premolars were divided into three groups (n = 15). Each disk was cut into two equal parts, in which one half formed the control. Thirty dentin samples were used for ion estimation and the other 15 for microhardness testing. Atomic absorption spectrophotometry, colorimetric and potentiometric titration analyses were performed for calcium, phosphate and fluoride ion detection, respectively. The antimicrobial efficacy was analyzed using pure culture of Streptococcus mutans and mixed flora. Results : Increase in the levels of calcium and phosphate ions was the highest in calcium hydroxide group. Both SDF and GC VII groups showed significant increase in fluoride ion levels. Samples treated with GC VII showed maximum increase in micro hardness. The highest zone of bacterial inhibition was found with SDF group. Conclusions : This in vitro study documented the remineralizing, re-hardening and antimicrobial efficacy of both SDF and GC VII and hence can act as effective IPC materials.

It is important for the clinician not only to gather as much information about a case as possible, but also to be able to correctly interpret the data to arrive at an accurate diagnosis. Occasionally, a case presents with symptoms that might be suggestive of a condition; however, the final diagnosis may be totally different. This paper reports on an interesting case of a true vertical root fracture, in an intact maxillary molar in a 55-year-old man. The case was misdiagnosed and treated as a periodontal defect for over two months. The paper discusses the various causes and diagnostic dilemmas of root fractures.

Objective The purpose of this in vitro study was to evaluate the effect of various root canal instrumentation techniques with different instrument tapers on cleaning efficacy and resultant vertical root fracture (VRF) strength of the roots. Study design Fifty human mandibular first premolar roots were enlarged to ISO size 20, inoculated with Enterococcus faecalis [ATCC2912] for 72 hours and divided into 5 groups: group I: prepared with .02 taper hand instruments ISO size 40; group II: Profile .04 taper size 40; group III: Profile .06 taper size 40; group IV: ProTaper size F4; and group V (control group) further divided into: Va: with bacterial inoculation and no mechanical instrumentation; and Group Vb: neither bacterial inoculation nor mechanical instrumentation. Cleaning efficacy was evaluated in terms of reduction of colony forming units (CFUs). The VRF strength was evaluated using D11 spreader as wedge in an Instron testing machine. Results Root canals instrumented with ProTaper and 6% Profile instruments showed maximum reduction in CFUs, with statistically insignificant difference between them. The VRF resistance decreased in all instrumented groups. The difference of VRF between 2% and 4% taper Profile groups was statistically insignificant ( P = .195). One-way analysis of variance showed that canals instrumented with ProTaper F4 showed maximum reduction in VRF resistance compared with control uninstrumented group. Conclusions Profile 6% taper instruments offer the advantage of maximum debridement without significant reduction in root fracture resistance.

Changing demography due to the increasing population of elderly persons the world over has raised new challenges in every sphere of life. The greatest challenge is to provide affordable, accessible, and equitable health care to this population. Oral health is an integral part of general health and affects physical and mental well-being and quality of life of elderly persons. To provide quality oral health care to the elderly, it is important to focus on education in geriatric dentistry, since it is known that education is closely linked to health care provision. It has been found that education in geriatric dentistry has wide variations in different parts of the world. Also, it is being taught at different levels: the predoctoral curriculum, postdoctoral certificate/diploma courses of varying duration by direct or distance mode using computer-assisted learning, degree courses of three years' duration, or continuing education programs. This article attempts to study geriatric dentistry education in global perspective. It is discussed in three sections: 1) varying concepts and methods of teaching, learning, and assessment in dental education; 2) status of geriatric dental education in developed and developing countries with emphasis on the Indian scenario; and 3) challenges and opportunities in developing geriatric dental education.