Comparison of the effectiveness of virtual reality-based education and conventional teaching methods in dental education: a systematic review.

BACKGROUND AND OBJECTIVES: Virtual reality dental simulators as an educational tool may create specific training conditions for dental students, allowing them to practice dental skills in a safe and controlled condition. This study aimed to investigate the effectiveness of virtual reality-based education in dental education compared to traditional education approaches. METHODS: In this systematic review, four databases (PubMed, Scopus, Web of Science, and Science Direct) were searched until 2023 following PRISMA guidelines. The Quality assessment and risk of bias were assessed by the Cochrane Collaboration Tool for RCTs and GRADE, respectively. Inclusion criteria were restricted to randomized or quasi-randomized trials about virtual reality efficacy in dental education. Two authors independently evaluated the data and reviewed the overall risk of bias for all selected studies. Study design, sample size, hardware, onset time of intervention, duration, and number of procedures performed were among the data extracted. RESULTS: From the 703 titles, 48 full texts were chosen for review, yielding 14 articles for final inclusion. The review of these articles indicated the effective role of virtual reality dental simulators in improving students' knowledge and practical skills. CONCLUSIONS: Based on our findings, adding haptic technology to virtual reality can improve students' practical skills, hand skills, theoretical knowledge, self-confidence, and learning environment. Although a fair amount of research needs to be done, notably on cost-effectiveness, student satisfaction, and other potentially adverse effects, virtual reality is a growing phenomenon with immense potential.

The effect of virtual reality on reducing patients' anxiety and pain during dental implant surgery.

BACKGROUND: Dental anxiety and pain pose serious problems for both patients and dentists. One of the most stressful and frightening dental procedures for patients is dental implant surgery; that even hearing its name causes them stress. Virtual reality (VR) distraction is an effective intervention used by healthcare professionals to help patients cope with unpleasant procedures. Our aim is to evaluate the use of high-quality VR and natural environments on dental implant patients to determine the effect on reducing pain and anxiety. METHODS: Seventy-three patients having two dental implant surgeries participated in a randomized controlled trial. One surgery was with VR, and one was without. Anxiety was measured with the the State-Trait Anxiety Inventory and the Modified Dental Anxiety Scale tests. The pain was measured with the Numerical Rating Scales. Patient satisfaction, surgeon distress, memory vividness, and time perception were evaluated. Physiological data were collected with biofeedback and neurofeedback device. RESULTS: VR effectively reduced anxiety and pain compared to no VR. Physiological data validated the questionnaire results. Patient satisfaction increased, with 90.4% willing to reuse VR. VR reduced time perception and memory vividness. CONCLUSION: Psychometric and psychophysiological assessments showed that VR successfully reduced patient pain and anxiety. More dental clinicians should use VR technology to manage patient anxiety and pain.

A study to investigate the effectiveness of the application of virtual reality technology in dental education.

BACKGROUND: Today, the use of virtual reality (VR) technology as an educational tool in dental education has expanded considerably. This study was aimed to evaluate the effectiveness of using VR technology in teaching neutral zone and teeth arrangement. METHODS: This randomized trial was conducted at Kermanshah University of Medical Sciences, Iran in 2019. The study sample consisted of 50 six-year dental students who were randomly divided into experimental (n = 25) and control (n = 25) groups. Students' performance in both groups was assessed using tests. A questionnaire was used to assess the usability of VR technology and students' satisfaction with it. RESULTS: All faculty members confirmed the usability of VR technology in dental education. The majority of students (76%) were highly satisfied with the use of this technology in their learning process. The mean score of students was significantly higher in the experimental group (16.92 ± 1.12) than in the control group (16.14 ± 1.18). CONCLUSION: In general, it can be argued that VR technology is useful and effective in the teaching-learning process. Therefore, its use in medical and dental schools can play an effective role in creating a dynamic, attractive, and successful learning environment.

Patient satisfaction with occlusal scheme of conventional complete dentures.

Occlusal scheme is a controversial topic that has been linked to patient satisfaction with conventional complete dentures (CCDs). This study aimed to compare the patient satisfaction with CCDs with four different occlusal schemes namely the lingualised occlusion (LO), buccalised occlusion (BO), fully bilateral balanced occlusion (FBBO) and partially group function occlusion (PGFO). In this clinical study, new CCDs were made for 121 patients; out of which, 97 patients (mean age of 57.87 ± 9.5 years) completed the 1-year follow-up. The CCD wearers were followed up at 1 month, 3 months and 1 year after CCD delivery. Data were collected via an interview and recorded in a checklist by a blinded examiner. The checklist included the demographic variables, the 19-item version of Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT), and seven 100-mm line visual analogue scales (VASs) to assess the items related to patient satisfaction. The Kruskal-Wallis and Friedman tests followed by post hoc tests were used to compare the variables among the 4 groups and between the 3 follow-ups. P-value ≤ .05 was considered statistically significant for all tests. The patients with BO presented higher satisfaction scores for comfort, stability and retention at the 1-year follow-up compared with PGFO. Both PGFO and FBBO groups had higher physical pain scores compared with BO and LO. The psychological discomfort scores of FBBO group were significantly higher than those in LO group. Pairwise comparisons revealed no significant differences in the general patient satisfaction and total OHIP-EDENT scores between the 4 groups. For most items, within-group analysis showed significant improvement of the satisfaction scores and reduction of domain scores over time.

Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis.

BACKGROUND: This meta-analysis evaluated the association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility. METHODS: We searched the Scopus, PubMed/Medline, Web of Science, and Cochrane Library databases to retrieve articles published by October 2019. Review Manager 5.3 software was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). The results of publication bias tests were retrieved by Comprehensive Meta-Analysis 2.0 software. RESULTS: A total of 150 relevant records were identified; out of which, 16 were entered into the analysis (4 studies assessed LTF, 11 ENAM, and 11 AMELX polymorphisms). Of all polymorphisms, there was a significant association only between ENAM rs3796704 polymorphism and dental caries susceptibility. Both ENAM rs3796704 and AMELX rs17878486 polymorphisms had a significant association with dental caries risk in the Caucasian ethnicity and the studies including caries-free control group. CONCLUSIONS: The results of this meta-analysis showed that the G allele and the GG genotype of ENAM rs3796704 were associated with an increased risk of caries in the case group compared with the control group. But there was no association between LTF rs1126478, ENAM (rs1264848 and rs3796703), and AMELX (rs946252, rs17878486, and rs2106416) polymorphisms and dental caries susceptibility.

Salivary and Serum Interferon-Gamma/Interleukin-4 Ratio in Oral Lichen Planus Patients: A Systematic Review and Meta-Analysis.

Background and Objectives: Interferon-gamma (IFN-γ)/interleukin-4 (IL-4) ratio may indicate a change in the immune response with a potential pathological effect presented in oral lichen planus (OLP) patients. Herein, this meta-analysis evaluated the role of serum and salivary interferon-gamma/interleukin-4 ratio in the severity and development of OLP. Materials and Methods: The Scopus, Cochrane Library, PubMed, and Web of Science databases were systematically searched to retrieve the relevant studies published up from the database inception to March 2019. The crude mean difference (MD) and 95% confidence interval (CI) were calculated by RevMan 5.3 software using a random-effects model. A sensitivity analysis was performed on the results using the CMA 2.0 software. A total of 98 studies were retrieved from the databases, of which at last seven studies were included in this meta-analysis. Results: The findings showed that the pooled MDs of serum and salivary IFN-γ/IL-4 ratio were -0.22 (95% CI: -1.16, 0.72; p = 0.64) and 0.17 (95% CI: -1.50, 1.84; p = 0.84) in OLP patients compared to controls, respectively. In addition, the pooled MDs of serum and salivary IFN-γ/IL-4 ratio were -0.15 (95% CI: -0.53, 0.23; p = 0.43) and -0.39 (95% CI: -0.63, -0.15; p = 0.001) in patients with erythematous/ulcerative subtype compared to patients with reticular subtype, respectively. Conclusions: In conclusion, the results of meta-analysis demonstrated that serum and salivary IFN-γ/IL-4 ratio cannot play a major role in OLP development and severity.

Surface Topography Steer Soft Tissue Response and Antibacterial Function at the Transmucosal Region of Titanium Implant.

Metallic dental implants have been extensively used in clinical practice due to their superior mechanical properties, biocompatibility, and aesthetic outcomes. However, their integration with the surrounding soft tissue at the mucosal region remains challenging and can cause implant failure due to the peri-implant immune microenvironment. The soft tissue integration of dental implants can be ameliorated through different surface modifications. This review discussed and summarized the current knowledge of topography-mediated immune response and topography-mediated antibacterial activity in Ti dental implants which enhance soft tissue integration and their clinical performance. For example, nanopillar-like topographies such as spinules, and spikes showed effective antibacterial activity in human salivary biofilm which was due to the lethal stretching of bacterial membrane between the nanopillars. The key findings of this review were (I) cross-talk between surface nanotopography and soft tissue integration in which the surface nanotopography can guide the perpendicular orientation of collagen fibers into connective tissue which leads to the stability of soft tissue, (II) nanotubular array could shift the macrophage phenotype from pro-inflammatory (M1) to anti-inflammatory (M2) and manipulate the balance of osteogenesis/osteoclasia, and (III) surface nanotopography can provide specific sites for the loading of antibacterial agents and metallic nanoparticles of clinical interest functionalizing the implant surface. Silver-containing nanotubular topography significantly decreased the formation of fibrous encapsulation in per-implant soft tissue and showed synergistic antifungal and antibacterial properties. Although the Ti implants with surface nanotopography have shown promising in targeting soft tissue healing in vitro and in vivo through their immunomodulatory and antibacterial properties, however, long-term in vivo studies need to be conducted particularly in osteoporotic, and diabetic patients to ensure their desired performance with immunomodulatory and antibacterial properties. The optimization of product development is another challenging issue for its clinical translation, as the dental implant with surface nanotopography must endure implantation and operation inside the dental microenvironment. Finally, the sustainable release of metallic nanoparticles could be challenging to reduce cytotoxicity while augmenting the therapeutic effects.

Clinical Marginal and Internal Adaptation of Single Metal-Ceramic Crowns Fabricated with Casting, Milling, and Milling/Sintering Methods.

PURPOSE: To compare the adaptation of single metal-ceramic crowns (MCCs) fabricated with three different methods: lost-wax metal casting (LMC), milling of hard cobalt-chromium (HCC) blanks, and milling of soft presintered cobalt-chromium (SCC) blanks. MATERIALS AND METHODS: In this double-blind parallel randomized clinical trial, 60 single MCCs were fabricated using three different methods. Adaptation of the copings was evaluated radiographically, visually, and microscopically. Data were compared among the three groups using the Kruskal-Wallis test, followed by the Dunn post hoc test, one-way ANOVA, and paired t test (α = .05). RESULTS: Radiographic data showed that the frequency of crowns with no marginal discrepancy was significantly higher in the SCC group than the LMC group. Evaluation of marginal adaptation with an explorer revealed that crowns with excellent marginal adaptation had lower frequency in the LMC group than the HCC and SCC groups. In the silicone replica technique, the recorded data revealed no significant difference. Application of porcelain veneering did not affect the adaptation of the copings. CONCLUSIONS: The SCC and HCC groups showed better clinical outcomes compared to the LMC group. However, all MCCs fabricated with the LMC method, milling of HCC blanks, and milling of SCC blanks had acceptable clinical adaptation. Int J Prosthodont 2023;36:581-587.

Effect of Methotrexate Injection on Orthodontic Tooth Movement: An Experimental Study on Rats.

INTRODUCTION: Knowledge about the effects of medications, vitamins, and various supplements on orthodontic tooth movement (OTM) is imperative for orthodontists. This study aimed to assess the effect of methotrexate (MTX) injection on OTM in rats. MATERIALS AND METHODS: Twenty-eight male Wistar rats were randomized into four groups (n = 7). The first molar and central incisor were connected using a nickel-titanium (NiTi) coil spring with a 50 g load in each rat. The two experimental groups received 0.75 mg/kg and 1.5 mg/kg MTX, respectively, intraperitoneally for 21 days. The negative control group did not receive any injection and did not undergo orthodontic treatment. The positive control group underwent orthodontic treatment and received 0.9% saline (NaCl) injections for 21 days. All rats were sacrificed with chloroform inhalation after 21 days; their maxilla was resected, and the mean number of Howship's lacunae, blood vessels, osteoclasts, and resorption lacunae was counted. The reduction in bone volume (bone volume to total volume ratio (BV/TV)) at the site of the maxillary molar was quantified by microcomputed tomography (micro-CT). RESULTS: OTM, the number of osteoclasts, and the number of blood vessels significantly increased in rats treated with MTX (P < 0.05). However, the increase in the number of Howship's lacunae and resorption lacunae was not significant (P > 0.05). Lower BV/TV in the MTX groups was in agreement with the increased number of osteoclasts. CONCLUSION: Injection of MTX can significantly increase OTM and decrease root resorption in rats.

A meta-analysis and trial sequential analysis of serum copeptin level in adult patients with Obstructive Sleep Apnoea Syndrome.

OBJECTIVE: Copeptin can act as a stable biomarker in inflammation and stress response that obstructive sleep apnoea syndrome (OSAS), can induce oxidative stress and consequently promotes systemic inflammation. The purpose of the study is to appraise serum copeptin level in adult patients with OSAS compared to the controls. MATERIAL AND METHODS: Electronic search was done in the databases of PubMed/Medline, Web of Science, Scopus, and Cochrane Library until June 2021, without any restrictions. For comparison of the serum copeptin level between groups, the mean difference (MD) and 95% confidence interval (CI) were calculated by the Review Manager 5.3 software. Trial sequential analysis (TSA) was used by applying TSA software. RESULTS: Among the databases, five articles (involving 495 OSAS patients and 135 controls) were included. To report the serum copeptin level in OSAS patients compared to controls, the pooled OR became 12.21pg/mL (95%CI: 2.31 to 22.11; P=0.02) and also the pooled OR for comparison of serum copeptin level in severe versus moderate/mild OSAS patients was 5.96pg/mL (95%CI: 1.46 to 10.47; P=0.009). The results of TSA illustrated that the Z-curve has not crossed the monitoring boundary curves and did not reach the required information size. CONCLUSIONS: The main findings recommended that copeptin had a significantly higher serum level in OSAS patients compared to controls, as well as a significantly higher level in severe patients compared to mild/moderate OSAS patients for the serum level of copeptin.

An overview of recent progress in dental applications of zinc oxide nanoparticles.

Nanotechnology is an emerging field of science, engineering, and technology concerning the materials in nanoscale dimensions. Several materials are used in dentistry, which can be modified by applying nanotechnology. Nanotechnology has various applications in dentistry to achieve reliable treatment outcomes. The most common nanometals used in dental materials are gold, silver, copper oxide, magnesium oxide, iron oxide, cerium oxide, aluminum oxide, titanium dioxide, and zinc oxide (ZnO). ZnO nanoparticles (NPs), with their unparalleled properties such as high selectivity, enhanced cytotoxicity, biocompatibility, and easy synthesis as important materials were utilized in the field of dentistry. With this background, the present review aimed to discuss the current progress and gain an insight into applications of ZnO NPs in nanodentistry, including restorative, endodontic, implantology, periodontal, prosthodontics, and orthodontics fields.

A PRISMA-compliant meta-analysis on association between X-ray repair cross complementing (XRCC1, XRCC2, and XRCC3) polymorphisms and oral cancer susceptibility.

BACKGROUND: Oral Cancer (OC) is one of the leading causes of death and the disease mainly occurs over 50 years of age. Herein, a meta-analysis aimed to assess the association between X-ray repair cross complementing (XRCC) polymorphisms and OC risk. METHODS: Four databases were searched extensively until June 5, 2020. Subgroup analysis, meta-regression, and funnel plots, as well as the quality assessment were estimated. RESULTS: Fifteen studies were entered to the analysis. With regards to allele, homozygote, heterozygote, recessive, and dominant models, the pooled ORs for XRCC1 rs1799782 polymorphism were 1.51 (P = 0.01), 1.45 (P = 0.11), 1.45 (P = 0.0003), 1.44 (P = 0.0002), and 1.29 (P = 0.26); for XRCC1 rs1799782 polymorphism were 1.65 (P = 0.11), 1.50 (P = 0.33), 1.06 (P = 0.83), 1.57 (P = 0.12), and 1.32 (P = 0.45); for XRCC1 rs25489 polymorphism were 0.01 (P = 0.19), 1.44 (P = 0.48), 1.21 (P = 0.72), 1.17 (P = 0.19), and 1.38 (P = 0.54); for XRCC2 rs2040639 polymorphism were 0.68 (P = 0.0002), 0.63 (P = 0.02), 0.95 (P = 0.92), 0.79 (P = 0.49), and 0.61 (P = 0.005); and for XRCC3 rs861539 polymorphism were 1.24 (P = 0.20), 1.28 (P = 0.48), 0.99 (P = 0.95), 1.15 (P = 0.46), and 1.52 (P = 0.15), respectively. CONCLUSIONS: The T allele and CT genotype of XRCC1 rs1799782 polymorphism had an elevated risk, whereas the G allele and GG genotype of XRCC2 rs2040639 polymorphism had a protective role in OC.

Optimum synthesis of polyhydroxybutyrate-Co3O4 bionanocomposite with the highest antibacterial activity against multidrug resistant bacteria.

Increased multidrug resistant (MDR) bacteria are considered one of the most challenging problems of the present century. The present study aimed to identify the optimum conditions for synthesis of Polyhydroxybutyrate-Co3O4 bionanocomposite with the highest antibacterial activity via in situ synthesis. Nine experiments with different amounts of polyhydroxybutyrate (PHB) biopolymer and Co3O4 nanoparticles and different stirring times were designed using Taguchi method. The antibacterial activity of synthesized nanocomposites against Staphylococcus aureus and Escherichia coli was evaluated using colony forming units (CFU) and disc diffusion methods. The characterizations of products were studied by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The synthesized bionanocomposites completely prevented the growth of bacteria under the conditions of experiments 5 (Co3O4 4 mg/ml, PHB 1 mg/ml and stirring time: 90 min) and 9 (Co3O4 8 mg/ml, PHB 2 mg/ml and stirring time: 60 min). The results showed that nanocomposite formation improved structural properties, thermal stability and antibacterial activity. PHB-Co3O4 bionanocomposite can be used in various fields of pharmacy, medicine and dentistry due to its desirable antibacterial properties.

Factors Affecting the Learning of Fixed Prosthodontics Course by Students at Kermanshah University of Medical Sciences.

AIM: The objective of this study was to investigate the factors affecting the learning of fixed prosthodontics course from the viewpoint of students and faculty members of Kermanshah Dentistry School. MATERIAL AND METHODS: This research was a descriptive-analytical study conducted using the convenient sampling method. A total of 72 students and 5 faculty members were included in the study. Data were collected using a researcher-made questionnaire containing two sections. The first section consists of demographic information, and the second section consists of 14 questions to evaluate the factors affecting the learning of the fixed prosthodontics course. RESULTS: From the students' point of view, there was a significant relationship between the effect of using clinical points during a teaching on the learning efficacy of the fixed prosthodontics course and gender (P = 0.028). There was a statistically significant relationship between the level of professor's knowledge regarding the modern educational methods on the learning of fixed prosthodontics course (P = 0.034). The factor of displaying and implementing practical work on the real patient was considered important by students, and having knowledge about modern educational methods was considered important by faculty members. CONCLUSIONS: It is recommended that appropriate educational planning be implemented to enhance students' practical work on the real patient and increase professors' knowledge about modern educational methods.

Applying the Taguchi Method to the Optimization of Anticancer Activity of Bacterial Alginate-CuO Bionanocomposite.

AIM: In recent decades, despite various types of cancer inflicting many people worldwide, the existing therapies are not satisfactory and have many side effects. The present study was conducted to optimise the synthesis of novel alginate-CuO nanocomposite with utmost anticancer activity. METHODS: In this study, 9 nanocomposites were designed using Taguchi method and three factors including copper oxide nanoparticles, alginate biopolymer and stirring times were assessed at three different levels. The anticancer activity of the synthesised nanocomposites was evaluated on the MCF-7 cell line using the MTT method. Using the Qulitek-4 software, we determined the optimum conditions for the synthesis of alginate-CuO nanocomposite with the highest anticancer activity. RESULTS: The results indicated that all three factors (copper oxide, alginate and stirring time) were effective on the anticancer activity of the alginate-CuO nanocomposite. Also, the nanocomposite produced under the conditions of experiment 9 (8 mg/ml of copper oxide, 2 mg/ml of alginate and 60 min of stirring time) provided the highest growth inhibition rate as 75.63% against cancer cells. CONCLUSION: The synthesised alginate-copper oxide nanocomposites in this study showed a significant anticancer effect. Therefore, the synthesised nanocomposite under optimal conditions can be used in the design of new anticancer drugs.

Optimisation of Cobalt Oxide Nanoparticles Synthesis as Bactericidal Agents.

AIM: With the increased bacterial resistance and the resulting problems in recent years, it seems necessary to find new biocompatible compounds to confront this problem. This research was conducted to optimise the synthesis of cobalt oxide nanoparticles with the highest antibacterial activity. METHODS: In the present study, 9 experiments were designed using the Taguchi method. The effect of three factors of cobalt nitrate, KOH and the stirring time in the synthesis of cobalt oxide nanoparticles with the highest antibacterial activity was investigated. The bactericidal effect of synthesised nanoparticles was evaluated using the colony-forming unit (CFU) and disk diffusion methods. The characteristics of nanoparticles were studied using the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and the scanning electron microscopy (SEM). RESULTS: The results indicated that all three evaluated factors were effective on the antibacterial properties of the synthesised nanoparticles. The best antibacterial activity of cobalt oxide nanoparticles was observed in experiment 9 (cobalt nitrate 0.6 M, KOH 2M and stirring time 60 min). The study of nanoparticles synthesised by FTIR, XRD, and SEM confirmed the formation of cobalt oxide nanoparticles with size (24 nm) and a proper structure (spinel structure). CONCLUSION: Due to the optimal antibacterial properties of the synthesised cobalt oxide nanoparticles, they can be used in the fabrication of dental and medical equipment with antibacterial properties.

Comparative evaluation of the efficacy of three methods of delivering calcium hydroxide into the root canal.

BACKGROUND: Calcium hydroxide, due to its favorable properties, such as an antimicrobial effect as well as its ability to dissolve necrotic tissues, inhibit tooth resorption and stimulate the formation of a hard tissue barrier, is widely used in root canal treatment. OBJECTIVES: The objective of this study was to compare the efficacy of 3 methods of delivery of calcium hydroxide into the canals. MATERIAL AND METHODS: This in vitro experimental study was performed on acrylic resin blocks with simulated curved canals (curvature of 24° and 44°). Calcium hydroxide was delivered into the canals with 3 different instruments : a hand file, a Lentulo and a rotary file. The data was analyzed using the three-way analysis of variance (ANOVA) and Tukey's test. RESULTS: The density of calcium hydroxide was significantly different among the 3 groups (p < 0.001). The manual delivery technique resulted in the lowest and using a rotary file in the highest density of calcium hydroxide (p < 0.001). The mean density of calcium hydroxide was significantly higher in the canals with curvature of 24°, irrespective of the delivery method (p < 0.001). The lowest mean density of calcium hydroxide was noted at 1 mm and 3 mm from the apex, whereas the highest mean density was noted at 11 mm from the apex, irrespective of delivery method (p < 0.001). CONCLUSIONS: A rotary file seems to be the most efficient instrument for delivering calcium hydroxide into the canals, especially into the apical region of canals with greater curvature.

The Role of Nanomaterials in the Treatment of Diseases and Their Effects on the Immune System.

Nanotechnology has been widely exploited in recent years in various applications. Different sectors of medicine and treatment have also focused on the use of nanoproducts. One of the areas of interest in the treatment measures is the interaction between nanomaterials and immune system components. Engineered nanomaterials can stimulate the inhibition or enhancement of immune responses and prevent the detection ability of the immune system. Changes in immune function, in addition to the benefits, may also lead to some damage. Therefore, adequate assessment of the novel nanomaterials seems to be necessary before practical use in treatment. However, there is little information on the toxicological and biological effects of nanomaterials, especially on the potential ways of contacting and handling nanomaterials in the body and the body response to these materials. Extensive variation and different properties of nanomaterials have made it much more difficult to access their toxicological effects to the present. The present study aims to raise knowledge about the potential benefits and risks of using the nanomaterials on the immune system to design and safely employ these compounds in therapeutic purposes.

Efficacy of CPP-ACP and CPP-ACPF for Prevention and Remineralization of White Spot Lesions in Orthodontic Patients: a Systematic Review of Randomized Controlled Clinical Trials.

INTRODUCTION: Enamel subsurface lesions or white spot lesions (WSLs) are commonly found in orthodontic patients with a prevalence of 5% to 97%. AIM: This systematic review aimed to evaluate the efficacy of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) for prevention and remineralization of WSLs in orthodontic patients in human randomized controlled clinical trials (RCTs). METHODS: Relevant articles were retrieved by searching the Web of Science, Scopus, PubMed, and Cochrane Library databases up to November 2018 with no language or date restriction. The collected data included examination method, groups included in each study with number of patients in each group, study design, follow-up period and summary of important findings of each study. The risk of bias of each study was assessed according to the guidelines of the Cochrane Collaboration's tool. RESULTS: Of 213 articles retrieved, 13 RCTs were included in this systematic review (none of them were included in the meta-analysis). Three articles showed superior efficacy of CPP-ACP for remineralization of WSLs while four studies reported the superior clinical efficacy of CPP-ACPF for this purpose. CONCLUSION: Both CPP-ACP and CPP-ACPF can decrease the prevalence and increase the remineralization of WSLs during/after orthodontic treatment.

Evaluation of serum and salivary interferon-γ levels in patients with oral lichen planus: a systematic review and meta-analysis of case-control studies.

OBJECTIVE: Cytokines have regulatory and leading roles in the immunopathogenesis of oral lichen planus (OLP). Here, we present the findings of a meta-analysis that evaluated serum and salivary interferon-γ (IFN-γ) levels in patients with OLP compared with those in controls and the correlation of this cytokine with the progression of OLP. STUDY DESIGN: Four databases-PubMed, Web of Science, Scopus, and Cochrane Library-were searched, from their start dates to November 2017, for reports in all languages on the effect of OLP on salivary and serum IFN-γ. RESULTS: Eleven studies were included and analyzed in this meta-analysis. The pooled mean difference (MD) values were estimated to be 3.60 pg/mL (P = .23) and -0.02 pg/mL (P = 1.00) for serum and salivary levels of IFN-γ, respectively, in the patients with OLP compared with controls. The pooled MD values were -2.52 pg/mL (P = .03) and -2.01 pg/mL (P = .20) for serum and salivary IFN-γ levels in the erosive type, respectively, compared with the nonerosive type. CONCLUSIONS: According to the results of meta-analysis, there was no statistically significant differences in IFN-γ levels between the OLP group and the control group both in serum and salivary levels and also between erosive and nonerosive types of OLP at the salivary level; so this cytokine is not considered to have an important role in the pathogenesis or severity of OLP.