Enhancing subgingival margin restoration: a comprehensive review and meta-analysis of deep margin elevation's impact on microleakage.

INTRODUCTION: Restorative dentistry faces complex challenges with deep proximal surface destruction, requiring novel approaches like DME (Deep Margin Elevation). In order to achieve the best results while treating severe tooth damage, this study examines the advantages, disadvantages, and possible collaborations of different treatments. AIMS: This systematic review investigates the efficacy of DME as an adjunctive procedure in restorative dentistry, specifically focusing on its impact on microleakage. METHODS: The study adheres to PRISMA guidelines and employs the PICOS framework for eligibility criteria. 394 potentially qualifying studies were discovered and thorough literature search was carried out via databases. After applying inclusion criteria, 7 studies were included in the analysis. Articles were selected based on criteria that included indirect restoration and performing DME and were compared with indirect restorations without DME. Composite resin was used for DME. Other materials for DME performing, including GI and composite flow, were systematically reviewed. Data analysis was done by biostat software (α = 0.05). RESULTS: The meta-analysis of selected studies reveals a statistically significant positive effect of DME on reduction of microleakage (p = 0.001). CONCLUSION: The results of this study underscore the potential of DME in addressing subgingival margin challenges and provide valuable insights for restorative dentistry practices.

Food insecurity and dental caries prevalence in children and adolescents: A systematic review and meta-analysis.

BACKGROUND: Food insecurity (FI) is associated with dietary practices, which can act as a risk factor for dental caries. AIM: This study aimed to investigate the relationship between FI and dental caries prevalence in children and adolescents. DESIGN: MEDLINE (via PubMed), EMBASE, SCOPUS, ISI web of knowledge, Cochrane, and ProQuest Dissertations & Theses Global database (up to April 19, 2022) as well as reference lists were searched. Eligible studies compared dental caries prevalence in food-secure and food-insecure individuals younger than 19 years. Two independent reviewers performed study selection, data extraction, and risk of bias assessment using a modified Newcastle-Ottawa Scale. Meta-analysis was performed, and the pooled odds ratio (OR) was calculated at 95% confidence interval (95% CI). RESULTS: Among the 1350 retrieved records, 10 cross-sectional reports were selected for systematic review. Six studies involving 8631 participants were included in the meta-analysis. More than half of the reports were published within the period 2019-2021. All studies except one were judged as low risk of bias. Overall, the prevalence of dental caries was greater among the food-insecure children and adolescents (OR: 2.01, 95% CI: 1.52-2.65, p < .001, I2 : 73.5%). Similarly, all three categories of FI were significantly associated with caries experience (marginal FI: OR: 1.88, 95% CI: 1.56-2.27, p < .001, I2 : 0.0%; low FI: OR: 2.42, 95% CI: 1.42-4.14, p = .001, I2 : 74.4%; very low FI: OR: 2.37, 95% CI: 1.88-3.00, p < .001, I2 : 0.0%). CONCLUSION: The results showed a significant association between FI status and dental caries in both childhood and adolescence; however, there was a lack of longitudinal studies for a better understanding of this association. Health policies leading to reduction in FI may also aim to reduce dental caries.

Reducing pain and discomfort associated with rubber dam clamp placement in children and adolescents: a systematic review and meta-analysis of effectiveness.

BACKGROUND: The application of rubber dams is a widely accepted method of tooth isolation in dental practice. Placement of the rubber dam clamp might be associated with levels of pain and discomfort, especially in younger patients. The purpose of the present systematic review is to evaluate the efficacy of the methods for reducing pain and discomfort associated with rubber dam clamp placement in children and adolescents. MATERIALS AND METHODS: English-language literature from inception until September 6th, 2022 was searched in MEDLINE (via PubMed), SCOPUS, Web of Science, Cochrane, EMBASE, and ProQuest Dissertations & Theses Database Global for articles. Randomized controlled trials (RCTs) comparing methods of reducing the pain and/or discomfort associated with rubber dam clamp placement in children and adolescents were retrieved. Risk of bias assessment was performed using a Cochrane risk of bias-2 (RoB-2) risk assessment tool and the certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) evidence profile. Studies were summarized and pooled estimates of pain intensity scores and incidence of pain were calculated. The meta-analysis was conducted in the following groups according to type of interventions (LA, audiovisual (AV) distraction, behavior management (BM), electronic dental anesthesia (EDA), mandibular infiltration, inferior alveolar nerve block (IANB), TA), outcome (intensity or incidence of pain), and assessment tool (face - legs - activity - cry - consolability (FLACC), color scale, sounds - motor - ocular changes, and faces pain scale (FPS)): (a) pain intensity using (LA + AV) vs (LA + BM), (b) pain intensity using EDA vs LA (c) presence or absence of pain using EDA vs LA (d) presence or absence of pain using mandibular infiltration vs IANB (e) Comparing pain intensity using TA vs placebo (f) Presence or absence of pain using TA vs placebo. Meta-analysis was conducted using StataMP software, version 17.0 (StataCorp, College Station, Texas). Restricted maximum-likelihood random effect model (REML), Mean difference (MD) with 95% confidence interval, and log odds ratio (OR) with 95% CI were calculated were calculated. RESULTS: Initially, 1452 articles were retrieved. Sixteen RCTs were finally included for reviewing and summarizing. Nine articles with a total of 867 patients were included for quantitative meta-analysis. The differences in pain intensity scores were not significant in any comparison groups (group a: [MD = -0.04 (95% CI = - 0.56, 0.47), P = 0.87, I2 = 0.00%], group b: [MD = 0.25 (95% CI = -0.08, 0.58), P = 0.14, I2 = 0.00%], group c [MD = -0.48 (95% CI = -1.41, 0.45), P = 0.31, I 2 = 0.00%], group d: [MD = -0.67 (95% CI = -3.17, 1.83), P = 0.60, I 2 = 0.00%], group e: [MD = -0.46 (95% CI = -l.08, 0.15), P = 0.14, I 2 = 90.67%], and group f: [MD = 0.61 (95% CI = -0.01, 1.23), P = 0.06, I 2 = 41.20%]. Eight studies were judged as having some concern for risk of bias and the remaining studies were considered as low risk for bias. The certainty of evidence was considered medium for all comparison groups. DISCUSSION: In the present meta-analysis, a considerable difference was obtained between the included studies regarding intervention methods and pain assessment tools and the analysis was performed in groups with small numbers of the studies. Owing to the mentioned variabilities and the small number of studies, the results of the analysis should be interpreted with caution. The indistinguishability of the manifestations of pain/discomfort from fear/anxiety, particularly in children, should also be considered while using the results of the present study. Within the limitations of the current study, no significant differences were found between the proposed methods for reducing pain and discomfort associated with rubber dam clamp placement in children and adolescents. A larger number of more homogenous studies regarding intervention methods and pain assessment tools need to be conducted in order to draw stronger conclusions. TRIAL REGISTRATION: This study was registered in PROSPERO (ID number: CRD42021274835) and research deputy of Mashhad University of Medical Sciences with ID number 4000838 ( https://research.mums.ac.ir/ ).

3D in vivo dosimetry of HDR gynecological brachytherapy using micro silica bead TLDs.

PURPOSE: This study aimed to evaluate the feasibility of defining an in vivo dosimetry (IVD) protocol as a patient-specific quality assurance (PSQA) using the bead thermoluminescent dosimeters (TLDs) for point and 3D IVD during brachytherapy (BT) of gynecological (GYN) cancer using 60 Co high-dose-rate (HDR) source. METHODS: The 3D in vivo absorbed dose verification within the rectum and bladder as organs-at-risk was performed by bead TLDs for 30 GYN cancer patients. For rectal wall dosimetry, 80 TLDs were placed in axial arrangements around a rectal tube covered with a layer of gel. Ten beads were placed inside the Foley catheter to get the bladder-absorbed dose. Beads TLDs were localized and defined as control points in the treatment planning system (TPS) using CT images of the patients. Patients were planned and treated using the routine BT protocol. The experimentally obtained absorbed dose map of the rectal wall and the point dose of the bladder were compared to the TPSs predicted absorbed dose at these control points. RESULTS: Relative difference between TPS and TLDs results were -8.3% ± 19.5% and -7.2% ± 14.6% (1SD) for rectum- and bladder-absorbed dose, respectively. Gamma analysis was used to compare the calculated with the measured absorbed dose maps. Mean gamma passing rates of 84.1%, 90.8%, and 92.5% using the criteria of 3%/2 mm, 3%/3 mm, and 4%/2 mm were obtained, respectively. Eventually, a "considering level" of at least 85% as pass rate with 4%/2-mm criteria was recommended. CONCLUSIONS: A 3D IVD protocol employing bead TLDs was presented to measure absorbed doses delivered to the rectum and bladder during GYN HDR-BT as a reliable PSQA method. 3D rectal absorbed dose measurements were performed. Differences between experimentally measured and planned absorbed dose maps were presented in the form of a gamma index, which may be used as a warning for corrective action.

Mitigation of radiation-induced hematopoietic system injury by melatonin.

BACKGROUND: Increased risks of exposure to accidental radiation events are a concern in today's world. Radiation terror, nuclear explosion, as well as accidental exposure to radioactive sources in some industries pose a threat to the life of exposed persons. Studies have been conducted using some low-toxic agents to mitigate radiation toxicity and increase survival probability for exposed people. In the current study, we aimed to show the mitigation of radiation-induced mortality and bone marrow toxicity using postirradiation treatment with melatonin. METHOD: Mice whole bodies were exposed to 4 or 7 Gy radiation followed by treatment with melatonin after 24 hours. Survival of mice with or without melatonin, the levels of peripheral cells, transforming growth factor (TGF)-ß and 8-hydroxy-2' -deoxyguanosine (8-OHdG) in the bone marrow, as well as the expression of NADPH oxidase (NOX)2 and NOX4 in bone marrow cells were evaluated. RESULTS: Whole body irradiation led to mortality 30 days after irradiation. However, melatonin treatment reduced mortality. Irradiation also showed severe reduction of lymphocytes, platelets, and red blood cells. The expressions of NOX2 and NOX4, in addition to TGF-ß level, were increased after exposure to radiation. Melatonin ameliorated the increased levels of these factors and improved the number of blood cells. CONCLUSIONS: Melatonin showed ability to mitigate radiation-induced hematopoietic system toxicity and also increased survival rate. These results suggest that melatonin could be a potential mitigator for accidental radiation events.

Management of oral mucositis in pediatric patients receiving cancer therapy: A systematic review and meta-analysis.

BACKGROUND: One of the most common complications of cancer chemotherapy is oral mucositis (OM). OM affects more than 75% of patients undergoing chemotherapy and represents a significant burden to patients and caregivers. We performed a systematic review and meta-analysis of published studies to investigate the effects of agents and techniques in reducing OM. PROCEDURE: This systematic review investigated, critically appraised, and rated the evidence on agents used to manage OM in children undergoing cancer therapy. A comprehensive search of the relevant literature was performed from January 2006 to December 2017. MEDLINE, Scopus, the Cochrane Database of Systematic Reviews, EMBASE, and the Web of Science were searched. Nine eligible studies were identified. Using random-effects models, standardized mean difference was estimated between treated and control groups across all studies. The Cochran test and the I2 index were performed for heterogeneity between studies. The significance level was set at P = 0.05. RESULTS: Palifermin reduced the incidence (OR = 4.131, P = 0.000), duration (St diff mean = 0.803, P = 0.000), and severity (St diff mean = 0.637, P = 0.000) of OM in pediatric cancer patients significantly. However, the laser did not show significant efficacy in decreasing the incidence rate of OM (OR = 2.870, P = 0.364). CONCLUSION: This review provided a comprehensive examination of available options for children who have OM. The results support the possibility of a positive effect of palifermin on reducing OM in children receiving cancer therapy.

Evaluating the effectiveness of combined radiotherapy and hyperthermia for the treatment response of patients with painful bony metastases: A phase 2 clinical trial.

INTRODUCTION: Since the survival time of patients with bony metastases has noticeably improved in recent years, these patients are at high risk of complications associated with this metastasis. Hence, the appropriate choice of treatment modality or combination of therapeutic approaches can lead to increasing bone pain relief, improving quality of life, etc. This study is aimed to evaluate the effectiveness of combined radiotherapy and hyperthermia for the treatment response of patients with painful bony metastases. PATIENTS AND METHODS: In a single-arm clinical trial, 23 eligible patients (14 female and 9 male) with the mean age of 67 years old and suffering from bony metastases were enrolled in the study. Two hours after radiotherapy, the patients underwent hyperthermia for 1 h in the supine position. All the patients completed the brief pain inventory (BPI) assessment tool and quality of life questionnaire (QLQ-C30) from the European Organization for Research and Treatment of Cancer (EORTC) at the baseline, end of the treatment and 1, 2 and 3 months thereafter. The response to the treatment was assessed as the zero score (complete response) or two or more than two-point drop of the worst pain within the preceding 24 h (partial response) during the 3-month posttreatment. RESULTS: All the pain intensity and interference scores, except the pain interference with the enjoyment of life score, significantly decreased. A total of 18 out of 23 patients (78%) achieved complete or partial response. The number of patients using pain relief medications decreased from 74% (n=17) at the baseline to 48% (n=11) 3 months later. Moreover, except for nausea and vomiting, appetite loss, diarrhea and financial impact problems, the patients' quality of life improved significantly in all the functional scales and symptoms within 3 months. CONCLUSION: This study showed that using hyperthermia in combination with radiotherapy significantly ameliorated bone pain among the patients suffering from cancer with painful bony metastases.

Histopathological and Functional Evaluation of Radiation-Induced Sciatic Nerve Damage: Melatonin as Radioprotector.

Background and Objectives: Radiotherapy uses ionizing radiation for cancer treatment. One of the side effects of radiotherapy is peripheral neuropathy. After irradiation, the first stage of neuropathy involves electrophysiological, biochemical and histopathological variations, while the fibrosis of soft tissues surrounding the exposed nerve occurs in the second stage. The present study aimed to examine the radioprotective effects of melatonin against ionizing radiation-induced sciatic nerve damage. Materials and Methods: Sixty male Wistar rats were assigned to four groups: C (Control + Vehicle), M (Melatonin), R (Radiation + Vehicle), MR (Radiation + Melatonin). Their right legs were irradiated with a 30 Gy single dose of gamma rays. Then, 100 mg/kg melatonin was administered to the animals 30 min before irradiation once daily (5 mg/kg) until the day of rats' sacrifice. Their exposed nerve tissues were assessed using the sciatic functional index (SFI) and histological evaluation. Results: Four, 12 and 20 weeks post irradiation, the SFI results showed that irradiation led to partial loss of motor nerve function after 12 and 20 weeks. Histological evaluation showed the various stages of axonal degeneration and demyelination compared to the C and M groups. Scar-like tissues were detected around the irradiated nerves in the R group at 20 weeks, but were absent in the MR group. The SFI and histological results of the R group showed partial nerve lesion. However, in all cases, treatment with melatonin prevented these effects. Conclusions: Results showed that melatonin has the potential to improve functional and morphological features of exposed sciatic nerves. This could possibly improve the therapeutic window of radiotherapy.

Maternal Folic Acid Supplementation and the Risk of Oral Clefts in Offspring.

INTRODUCTION: There is controversial evidence from the literature regarding the protective effect of folic acid supplementation during pregnancy against orofacial clefts. The authors undertook this meta-analysis to assess whether folate supplementation during pregnancy can reduce the risk of nonsyndromic cleft lip with or without cleft palate (CL/P) and cleft palate only (CPO) in infants. METHODS: Eligible articles were identified by searching databases, including PubMed, Medline, Scopus, ISI (Web of Knowledge) to September 2017. A meta-analysis was performed to evaluate the effects of maternal supplementation on oral clefts. Odds ratios (ORs) and 95% confidence intervals (CIs) were pooled using Stata software. Publication bias was assessed by the Begg and Egger test. (Registration ID: CRD42018083922) RESULTS:: Out of the 1630 articles found in the authors' initial literature searches, 6 cohort studies, and 31 case-control studies were included in the authors' final meta-analysis. The results of the main analysis revealed that maternal folate supplementation was associated with a modest but statically significant decreased risk of all cleft subtypes (OR = 0.69, 95% CI: 0.60, 0.78). Folic acid intake alone was inversely associated with CL/P (OR = 0.73, 95% CI: 0.62-0.85,) but to a lesser extent than CPO (OR = 0.75, 95% CI = 053-1.04). Multivitamin intake had a significant protective effect for CL/P (OR = 0.65 95% CI = 0.55-0.80) as well as CPO (OR = 0.69, 95% CI = 0.53-0.90). CONCLUSIONS: Our results indicate that maternal supplementation in early pregnancy reduces the risk of nonsyndromic CL/P and CPO in infants. These data can serve to reassure women planning a pregnancy to consume multivitamins during the periconception period to protect against oral clefts.

Can Chlorhexidine enhance the Bond Strength of Self-etch and Etch-and-rinse Systems to Primary Teeth Dentin?

Introduction: Modifying the durability of resin bonding systems resulted in introducing materials with cross-link property, such as chlorhexidine (CHX) that can promote the strength of resin-dentin bonding. The aim of this study was evaluation of the effect of CHX on shear bond strength (SBS) of self-etch (SE) and etch-and-rinse (E&R) bonding systems to the primary teeth dentin. Materials and methods: In this in vitro study, 40 freshly extracted primary molars collected and were cut mesiodistally, and then the buccal and lingual surface enamel was grounded. The specimens were randomly divided into two groups: I: Single Bond adhesive and II: Clearfil SE Bond adhesive. Then, each group was divided into two subgroups: On the buccal surface of each sample CHX was applied for 30 seconds and on the lingual surface of (I2, II2 groups), CHX was not applied. The SBS (MPa) of samples was assessed using the Zwick universal testing machine. Data were analyzed by paired t-test and independent t-test using Statistical Package for the Social Sciences (SPSS), version 16. Results: The mean SBS was significantly higher in the Single Bond group with CHX (66.45 ± 8.3) than without CHX (25.43 ± 12.94) in the nonaging group (p = 0.002). There was no significant difference in the mean SBS in the Clearfil SE Bond group with CHX and without CHX in the aging and nonaging groups. Conclusion: CHX had positive influence on immediate SBS of Single Bond adhesive to primary teeth dentin. In addition, no positive effect has been seen in the Clearfil SE Bond system. Clinical significance: Now more researches are needed about the recommendation of CHX in resin restorations of primary teeth. Keywords: Chlorhexidine, Etch-and-rinse adhesive, Failure pattern, Self-etch adhesive, Shear bond strength.

Dosimetric characteristics of LinaTech DMLC H multi leaf collimator: Monte Carlo simulation and experimental study.

This study evaluated the basic dosimetric characteristics of a Dynamic Multi Leaf Collimator (DMLC) using a diode detector and film measurements for Intensity Modulated Radiation Therapy Quality Assurance (IMRT QA). The EGSnrc Monte Carlo (MC) simulation system was used for the determination of MLC characteristics. Radiation transmission and abutting leaf leakage relevant to the LinaTech DMLC H were measured using an EDGE detector and EBT3 film. In this study, the BEAMnrc simulation code was used for modeling. The head of Siemens PRIMUS linac (6 MV) with external DMLC H was entered into a BEAMnrc Monte Carlo model using practical dosimetry data. Leaf material density, as well as interleaf and abutting air gaps were determined according to the computed and measured dose profiles. The IMRT QA field was used to evaluate the dose distribution of the simulated DMLC H. According to measurements taken with the EDGE detector and film, the total average measured leakage was 1.60 ± 0.03% and 1.57 ± 0.05%, respectively. For these measurements, abutting leaf transmission was 54.35 ± 1.85% and 53.08 ± 2.05%, respectively. To adapt the simulated leaf dose profiles with measurements, leaf material density, interleaf and abutting air gaps were adjusted to 18 g/cm3 , 0.008 cm and 0.108 cm, respectively. Thus, the total average leakage was estimated to be about 1.59 ± 0.02%. The step-and-shoot IMRT was implemented and 94% agreement was achieved between the film and MC, using 3%-3 mm gamma criteria. The results of this study showed that the dosimetric characteristics of DMLC H satisfied international standards.

Effect of Tannic Acid on Bond Strength of Etch and Rinse and Self-etch Adhesive Systems in Dentin of Primary Teeth.

INTRODUCTION: One of the possible mechanisms for the gradual destruction of bond strength in dentin-resin interface, could be due to the demineralized unstable collagen matrix. Use of protease inhibitors, such as tannic acid (TA) could prevent destruction of collagen fibers. The aim of this study was to compare the TA effect on bond strength of etch and rinse and self-etch adhesive systems in the dentin of primary teeth. MATERIALS AND METHODS: This in vitro study was done on 40 extracted primary molar teeth. The teeth were sectioned in the mesiodistal direction, and enamel of buccal and lingual surfaces was removed. Samples were randomly divided into four groups: Single bond (SB) + TA, SB, Clearfil SE Bond (CSB) + TA, and CSB. Then, Z250 and Clearfil AP-X composites were cured on the surfaces of SB and CSB groups respectively. After that, all samples were divided into aging and non-aging groups. For 3 months, samples were placed under 1,000 thermal cycles in aging group. Subsequently, the shear bond strengths of all groups were measured by the International testing machine, and failure mode was evaluated by an optical stereomicroscope. Data were analyzed with paired t-test and independent t-test. RESULTS: Tannic acid induced a significant reduction in the immediate bond strength of adhesive SB. Meanwhile, TA had no significant effect on shear bond strength of the CSB system. CONCLUSION: Based on our findings, use of TA is not recommended with SB and CSB adhesives on primary teeth. CLINICAL SIGNIFICANCE: Tannic acid may not be considered in resin restorations of primary teeth.

The most-cited articles in dental, oral, and maxillofacial traumatology during 64 years.

BACKGROUND AND AIM: Citation analysis helps to identify the research trends within a research field and helps to identify the most frequently occurring parameters. The aim of this study was to identify the 100 most-cited articles in the field of dental, oral, and maxillofacial traumatology over the past 64 years. MATERIAL AND METHODS: A comprehensive list of the most-cited articles in dental, oral, and maxillofacial trauma was compiled using 'All Databases' section of the ISI Web of Knowledge. Related articles were considered to be those articles in which part or all of the experiment or study was related to dental and/or oral and maxillofacial trauma. In case reports, if a part of a treatment plan was related to the topic, that article was considered to be relevant. The characteristics analyzed included number of citations, authors, journals, institution, country of origin, publication year, article type, study material, and topic. RESULTS: The number of citations for each article ranged from 69 to 229. The journal Dental Traumatology was the most represented, followed by the journal Oral and Maxillofacial Surgery. Of the 100 articles, 83% were original articles, 15% were review articles, and 2% were case report/case series. Therapy and prognosis-related topics were the most common topics. Most articles came from institutions in the United States, followed by the Scandinavian countries. University Hospital of Copenhagen was the source of the highest number (34) of the most-cited articles; the same author wrote or co-wrote 22 of the 100 most-cited articles. CONCLUSION: The list of most-cited articles in the field of dental, oral, and maxillofacial traumatology gives a good scientometric picture of trauma research in the world. A large number of the most-cited articles are mainly from the field of dental traumatology and originate from a few research teams.

Consequences of lethal-whole-body gamma radiation and possible ameliorative role of melatonin.

Gamma radiation induces the generation of free radicals, leading to serious cellular damages in biological systems. Radioprotectors act as prophylactic agents that are administered to shield normal cells and tissues from the deleterious effects of radiation. Melatonin synergistically acts as an immune-stimulator and antioxidant. We investigated the possible radioprotective role of melatonin (100 mg/kg i.p.) against lethal-whole-body radiation- (10 Gy) induced sickness, body weight loss, and mortality in rats. Results of the present study suggest that exposure to lethal-whole-body radiation incurred mortality, body weight loss, and apoptosis and it also depleted the immunity and the antioxidant status of the rats. Our results show that melatonin pretreatment provides protection against radiation induced mortality, oxidative stress, and immune-suppression. The melatonin pretreated irradiated rats showed less change in body weight as compared to radiation only group. On the other hand, melatonin appeared to have another radioprotective role, suggesting that melatonin may reduce apoptosis through a caspase-3-mediated pathway by blocking caspase-3 activity.

Comparison of bond strength of self-adhesive and self-etch or total-etch resin cement to zirconia: A systematic review and meta-analysis.

The aim of this study was to systematically compare the bond strength of self-adhesive and self-etch or total-etch resin cement to zirconia. The PubMed, ISI (all), and Scopus databases were searched for the selected keywords up to November 1, 2021, without date or language restrictions. In vitro studies comparing the bond strength of self-adhesive and self-etch or total-etch resin cement to zirconia were eligible for inclusion in the study. The selected articles were divided into four groups based on the type of resin cement and the storage time. Statistical analysis was performed using the Biostat Comprehensive Meta-Analysis Software version 2 (α = 0.05). The effect of conventional cement ( Glass Ionomer (GI), Resin Modified Glass Ionomer (RMGI) and zinc phosphate) was analyzed using descriptive analysis. The initial search yielded 376 articles, of which 26 were selected after a methodological assessment. Two reviewers independently extracted data and assessed the risk of bias. The results showed that the immediate or delay bond strength of the self-adhesive resin cement to zirconia has no significant difference with the bond strength of self-etch resin cement to zirconia. The immediate and delay bond strength of total-etch cement-zirconia was significantly lower than that of self-adhesive cement-zirconia (P = 0.00). A descriptive analysis of the selected articles showed that the bond strength of self-adhesive resin cement to zirconia was significantly higher than total-etch cement. The results of the meta-analysis showed that both self-adhesive and self-etch resin cement (if applied according to their manufacturer's instruction) are suitable for bonding to zirconia.

Monte Carlo characterization of biocompatible beta-emitting 90Y glass seed incorporated with the radionuclide 153Sm as a SPECT marker for brachytherapy applications.

A glass seed consisting of the ß--emitting radionuclide 90Y incorporated with radionuclide 153Sm as SPECT marker is proposed for potential application in brachytherapy in order to reduce the undesirable dose to healthy adjacent organs. The aim of this work is to determine the dosimetric characteristics, as suggested in the AAPM TG-60/TG-149 reports, for this seed using Monte Carlo simulation. Monte Carlo codes MCNP5, EGSnrc, and FLUKA were used to calculate the absorbed dose distribution around the seed. Dosimetric parameters, such as reference absorbed dose rate, radial dose function, and one-dimensional (1D) and two-dimensional (2D) anisotropy functions, were obtained. The computational results from these three codes are in agreement within 5.4% difference on average. The absorbed dose rate at the reference point was estimated to be 5.01 cGy h-1 µCi-1 and self absorption of YAS glass seed amounted to 30.51%. The results showed that, with thermal neutron bombardment of 5 hours in a typical flux, sufficient activity for applications in brachytherapy may be achieved. With a 5 mCi initial activity, the total dose of a YAS glass seed was estimated to be 1.38 Gy at 1.0 cm from the seed center. Comparing with gamma emitting seeds, the 90Y seed could reduce undesirable doses to adjacent organs, because of the rapid dose falloff of beta ray. Because of the high R90 value of 5.5 mm, fewer number of 90Y seeds will be required for an interstitial brachytherapy treatment using permanent implant, in comparison with other beta-emitting seeds. The results would be helpful in the development of the radioactive implants using 90Y glass seeds for the brachytherapy treatment.

Investigating the attenuating effect of telmisartan against radiation-induced intestinal injury using 18F-FDG micro-PET imaging.

BACKGROUND AND OBJECTIVE: This study was aimed to investigate the ability of 18F-Fluro-deoxy-glucose (18F-FDG)-based micro-positron emission tomography (microPET) imaging to evaluate the efficacy of telmisartan, a highly selective angiotensin II receptor antagonist (ARA), in intestinal tissue recovery process after in vivo irradiation. METHODS: Male Balb/c mice were randomly divided into four groups of control, telmisartan, irradiation, and telmisartan + irradiation. A solution of telmisartan in phosphate-buffered saline (PBS) was administered orally at 12 mg/kg body weight for seven consecutive days prior to whole body exposing to a single sub-lethal dose of 5 Gy X-rays. The mice were imaged using 18F-FDG microPET at 9 and 30 days post-irradiation. The 18F-FDG uptake in jejunum was determined according to the mean standardized uptake value (SUVmean) index. Tissues were also processed in similar time points for histological analysis. RESULTS: The 18F-FDG microPET imaging confirmed the efficacy of telmisartan as a potent attenuating agent for ionizing radiation-induced injury of intestine in mice model. The results were also in line with the histological analysis indicating that pretreatment with telmisartan reduced damage to the villi, crypts, and intestinal mucosa compared with irradiated and non-treated group from day 9 to 30 after irradiation. CONCLUSION: The results revealed that 18F-FDG microPET imaging could be a good candidate to replace time-consuming and invasive biological techniques for screening of radioprotective agents. These findings were also confirmed by histological examinations which indicated that telmisartan can effectively attenuates radiation injury caused by ionizing-irradiation.

Evaluation of the Effect of Maternal Education on Toddler Dental Plaque Removal Based on a Health Belief Model.

Objectives: The objective of this study was to investigate the impact of an educational intervention, guided by the Health Belief Model (HBM), on promoting preventive behaviors among mothers to combat early childhood caries (ECC) in toddlers aged 12 to 18 months. Materials and Methods: This single-blind interventional study evaluated 92 toddlers between 12 to 18 months and their mothers, who were selected by stratified random sampling. Data regarding demographic and nutritional factors were collected using a questionnaire. The dental status of children was evaluated by clinical examination and measuring the plaque index (PI) of maxillary central incisors and the dmfs index. A pamphlet designed according to the HBM was used for oral hygiene instruction in both the intervention and control groups. All of the mothers in the intervention group received a music file to listen to when brushing their children's teeth. Data were analyzed using chi-square, Fisher exact, Mann-Whitney, and Wilcoxson tests. P<0.05 was considered significant. Results: No significant correlation was noted between the daily frequency of sugary substance intake and primary PI in the intervention or control group with/without dental plaque (P>0.05). In the intervention group, PI significantly decreased after the intervention compared to baseline (P<0.001). However, there was no significant change in PI after the intervention in the control group compared with baseline (P=0.1). Conclusion: The findings indicate that a combination of educational intervention and incentives, such as using age-appropriate music for toddlers, can significantly enhance mothers' effectiveness in removing dental plaque.

Melatonin may play a role in modulation of bax and bcl-2 expression levels to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

The close relationship between free radicals effects and apoptosis process has been proved. Melatonin has been reported as a direct free radical scavenger. We investigated the capability of melatonin in the modification of radiation-induced apoptosis and apoptosis-associated upstream regulators expression in rat peripheral blood lymphocytes. Rats were irradiated with a single whole body Cobalt 60-gamma radiation dose of 8Gy at a dose rate of 101cGy/min with or without melatonin pretreatments at different concentrations of 10 and 100mg/kg body weight. The rats were divided into eight groups of control, irradiation-only, vehicle-only, vehicle plus irradiation, 10mg/kg melatonin alone, 10mg/kg melatonin plus irradiation, 100mg/kg melatonin alone and 100mg/kg melatonin plus irradiation. Rats were given an intraperitoneal (IP) injection of melatonin or the same volume of vehicle alone 1h prior to irradiation. Blood samples were taken 4, 24, 48 and 72h after irradiation for evaluation of flow cytometric analysis of apoptotic lymphocytes using Annexin V/PI assay and measurement of bax and bcl-2 expression using quantitative real-time PCR (RT(2)qPCR). Irradiation-only and vehicle plus irradiation showed an increase in the percentage of apoptotic lymphocytes significantly different from control group (P<0.01), while melatonin pretreatments in a dose-dependent manner reduced it as compared with the irradiation-only and vehicle plus irradiation groups (P<0.01) in all time points. This reduced apoptosis by melatonin was related to the downregulation of bax, upregulation of bcl-2, and therefore reduction of bax/bcl-2 ratio. Our results suggest that melatonin in these doses may provide modulation of bax and bcl-2 expression as well as bax/bcl-2 ratio to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

Comparison of the Success Rate of Filled and Unfilled Resin-Based Fissure Sealants: A Systematic Review and Meta-Analysis.

Objectives: Incorporation of fillers might improve the physical properties of sealants. This systematic review and meta-analysis evaluated the retention and caries development rate of filled and unfilled fissure sealants. Materials and Methods: This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The PubMed, Scopus, Embase, Cochrane Database of Systematic Reviews, and ISI Web of Knowledge were searched until October 24, 2019. The risk of bias (ROB) was assessed for the included studies based on the Cochrane collaboration common scheme for bias, and the meta-analysis was performed through a random effects model. Results: The search resulted in 6,336 unrepeated relevant studies. After the title, abstract and full-text screening, 19 studies with 26 comparing groups were finally included in this systematic review and meta-analysis. According to the included studies, both retention rate and caries development in filled and unfilled resin-based sealants did not significantly differ within 2 years of follow-up. Conclusion: Since there was no significant difference in the retention rate and caries development between filled and unfilled sealants, it seems that the final decision should be made uniquely for each patient according to the type of fissure, patient's age, habits, etc.