Orthodontic adhesive loaded with different proportions of ZrO2 silver-doped nanoparticles: An in vitro µTBS, SEM, EDX, FTIR, and antimicrobial analysis.

Zirconium dioxide silver-doped nanoparticles (ZrO2AgDNPs) impacts the adhesive material in terms of its physical characteristics, antimicrobial properties, degree of conversion (DC), and micro-tensile bond strength (µTBS) of orthodontic brackets to the enamel surface. A comprehensive methodological analysis utilizing a range of analytical techniques, including scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, DC analysis, and µTBS testing. A light-curable orthodontic adhesive, specifically Transbond XT, was combined with ZrO2AgDNPs at 2.5% and 5%. As a control, an adhesive with no incorporation of ZrO2AgDNPs was also prepared. The tooth samples were divided into three groups based on the weightage of NPs: group 1: 0% ZrO2AgDNPs (control), group 2: 2.5 wt% ZrO2AgDNPs, and group 3: 5 wt% ZrO2AgDNPs. EDX graph demonstrated silver (Ag), Zirconium (Zr), and Oxygen (O2), The antibacterial efficacy of adhesives with different concentrations of NPs (0%, 2.5%, and 5%) was assessed using the pour plate method. The FTIR spectra were analyzed to identify peaks at 1607 cm-1 corresponding to aromatic CC bonds and the peaks at 1638 cm-1 indicating the presence of aliphatic CC bonds. The µTBS was assessed using universal testing machine (UTM) and bond failure of orthodontic brackets was seen using adhesive remanent index (ARI) analysis. Kruskal-Wallis test assessed the disparities in survival rates of Streptococcus mutans. Analysis of variance (ANOVA) and post hoc Tukey multiple comparisons test calculated µTBS values. The lowest µTBS was observed in group 1 adhesive loaded with 0% ZrO2AgDNPs (21.25 ± 1.22 MPa). Whereas, the highest µTBS was found in group 3 (26.19 ± 1.07 MPa) adhesive loaded with 5% ZrO2AgDNPs. ZrO2AgDNPs in orthodontic adhesive improved µTBS and has acceptable antibacterial activity against S mutans. ZrO2AgDNPs at 5% by weight can be used in orthodontic adhesive alternative to the conventional method of orthodontic adhesive for bracket bonding. RESEARCH HIGHLIGHTS: The highest µTBS was found in orthodontic adhesive loaded with 5% ZrO2AgDNPs. ARI analysis indicates that the majority of the failures fell between 0 and 1 among all investigated groups. The colony-forming unit count of S. mutans was significantly less in orthodontic adhesive loaded with nanoparticles compared with control. The 0% ZrO2AgDNPs adhesive showed the highest DC.

A novel antibacterial and fluorescent coating composed of polydopamine and carbon dots on the surface of orthodontic brackets.

Many kinds of antibacterial coatings have been designed to prevent the adherence of bacteria onto the surface of a fixed orthodontic device of brackets. However, the problems such as weak binding force, undetectable, drug resistance, cytotoxicity and short duration needed to be solved. Thus, it has great value in developing novel coating methods with long-term antibacterial and fluorescence properties according to the clinical application of brackets. In this study, we synthesized blue fluorescent carbon dots (HCDs) using the traditional Chinese medicinal honokiol, which could cause irreversible killing effects on both gram-positive and gram-negative bacteria through positive charges on the surface and inducing reactive oxygen species (ROS) production. Based on this, the surface of brackets was serially modified with polydopamine and HCDs, taking advantage of the strong adhesive properties as well as the negative surface charge of polydopamine particles. It is found that this coating exhibits stable antibacterial properties in 14 days with good biocompatibility, which can provide a new solution and strategy to solve the series of hazards caused by bacterial adhesion on the surface of orthodontic brackets.

The bactericidal and biofilm removal effect of super reducing water on Streptococcus mutans in three types of orthodontic brackets.

PURPOSE: To investigate the bactericidal and biofilm removal effect of super reducing water (SRW) on Streptococcus mutans (S. mutans) adhered to orthodontic brackets, in vitro. METHODS: Three types of brackets were bonded to aluminum disks. After the formation of S. mutans biofilms on the surfaces, the brackets were divided into three groups (n = 44 each) based on their exposure to SRW: group 1, no treatment; group 2, treated for 5 min; and group 3, treated for 10 min. Total viable counts, adenosine triphosphate measurements, crystal violet assay, and scanning electron microscopy were used to evaluate the effect of SRW. RESULTS: The bacterial counts in groups 2 and 3 were significantly lower than those in group 1 (P < 0.001); however, no significant differences were observed between groups 2 and 3. Marked decreases in the number of bacterial colonies and extent of biofilm formation were observed in groups 2 and 3 compared to group 1. No significant differences in the number of bacterial colonies and amount of biofilm were observed among the three types of brackets in each group. CONCLUSION: These findings indicate the bactericidal and biofilm removal effect of SRW treatment on S. mutans adhered to orthodontic brackets.

Gold-oxoborate nanocomposite-coated orthodontic brackets gain antibacterial properties while remaining safe for eukaryotic cells.

The study's main objective is to limit bacterial biofilm formation on fixed orthodontic appliances. Bacterial biofilm formation on such devices (e.g., brackets) causes enamel demineralization, referred to as white spot lesions (WSL). WSL is significant health, social and economic problem. We provide a nanotechnology-based solution utilizing a nanocomposite of gold nanoparticles embedded in a polyoxoborate matrix (BOA: B-boron, O-oxygen, A-gold, Latin aurum). The nanocomposite is fully inorganic, and the coating protocol is straightforward, effective, and ecologically friendly (low waste and water-based). Prepared coatings are mechanically stable against brushing with a toothbrush (up to 100 min of brushing). Bacteria adhesion and antibacterial properties are tested against Streptococcus mutans-common bacteria in the oral cavity. BOA reduces the adhesion of bacteria by around 78%, that is, from around 7.99 × 105  ± 1.33 × 105  CFU per bracket to 1.69 × 105  ± 3.07 × 104  CFU per bracket of S. mutans detached from unmodified and modified brackets, respectively. Modified fixed orthodontic brackets remain safe for eukaryotic cells and meet ISO 10993-5:2009 requirements for medical devices. The gathered data show that BOA deposited on orthodontic appliances provides a viable preventive measure against bacteria colonization, which presents frequent and significant complications of orthodontic treatment.

Study on the role of nano antibacterial materials in orthodontics (a review).

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.

Self-ligating brackets exhibit accumulation of high levels of periodontopathogens in gingival crevicular fluid.

Different types of brackets seem to influence the disruption of the oral microbial environment. Therefore, the aim of this study was to evaluate the influence of self-ligating brackets on the gingival crevicular fluid levels of the putative periodontal pathogens Aggregatibacter actinomycetemcomitans sorotype a (Aaa), Tannerella forsythia, Fusobacterium nucleatum, and Porphyromonas gingivalis. Sixty samples of crevicular fluid of twenty patients (11 boys and 9 girls) were analysed at baseline (T0) and after 30 (T1) and 60 (T2) days of bonding of the self-ligating (In-Ovation®R, Dentsply, GAC or SmartClip™, 3 M Unitek, Monrovia, CA, USA) and of one conventional bracket (Gemini™, 3 M Unitek, Monrovia, CA, USA) used with elastomeric ligatures. Total DNA from samples was extracted using CTAB-DNA precipitation method and Real-time PCR was performed to analyse bacterial level. Non-parametric Friedman and Wilcoxon tests were used for data analysis (p value of < 0.05). F. nucleatum presented a different level among the different brackets at T1 (p = 0.025), the highest level in the Gemini™ bracket when compared to the SmartClip™ bracket (p = 0.043). P. ginigvalis levels increased in the In-Ovation®R (p = 0.028) at T1. The subgingival levels of bacterial species associated with periodontal disease P. ginigvalis increased in the self-ligating brackets In-Ovation®R.Clinical Relevance: Some kinds of brackets could provide more retentive sites than others, and it seems to modulate the subgingival microbiota, since, in this study, we could observe the increase of the species associated with periodontal disease. Preventive protocols should be adopted in the use of self-ligating brackets.

Enhanced reduction of polymicrobial biofilms on the orthodontic brackets and enamel surface remineralization using zeolite-zinc oxide nanoparticles-based antimicrobial photodynamic therapy.

The aim of this study was to evaluate the anti-biofilm and anti-metabolic activities of zeolite-zinc oxide nanoparticles (Zeo/ZnONPs)-based antimicrobial photodynamic therapy (aPDT) against pre-formed polymicrobial biofilms on the orthodontic brackets, as well as, assess the remineralization efficacy on polymicrobial biofilms induced enamel lesions. Following synthesis and characterization of Zeo/ZnONPs, cell cytotoxicity, hemolytic effect, and intracellular reactive oxygen species (ROS) production were determined. The anti-biofilm and anti-metabolic activities of aPDT using different concentrations of Zeo/ZnONPs were investigated. Microhardness tester and DIAGNOdent Pen were used to evaluate the changes of remineralization degree on the treated enamel slabs duration 1 and 3 months. No significant cytotoxicity and erythrocyte hemolysis were observed in treated cells with Zeo/ZnONPs. When irradiated, suggesting that the Zeo/ZnONPs were photoactivated, generating ROS and leading to reduce dose-dependently the cell viability and metabolic activity of polymicrobial biofilms. Also, the enamel surface microhardness value of exposed enamel showed a steady increase with the concentration of Zeo/ZnONPs. No statistically significant differences were shown between aPDT and sodium fluoride varnish as the control group. Overall, Zeo/ZnONPs-based aPDT with the greatest remineralization efficacy of enamel surface can be used as an anti-biofilm therapeutic method, which is involved with their potent ability to produce ROS.

Green tea extract solutions can control bacterial biofilms formed on space maintainers.

BACKGROUND: Microorganisms in the mouth are protected from negative environmental conditions by forming biofilms; however, the use of anti-plaque agents in children is not preferred due to toxic side effects. Green tea has been reported to have anti-microbial and anti-dental caries properties. AIMS: The aim of this study was to assess the ability of green tea extract to prevent the formation of biofilm on the teeth of children using space maintainers. METHODS: Bacteria were isolated from samples obtained from children aged between 8 and 10 years. The micro-titer plate method and Congo red agar were used to assay biofilm formation. Green tea leaves were obtained from Rize, Turkey. Methanol, hexane and distilled water were used for preparing the extracts. The effects of green tea extract and chlorhexidine on biofilm formation were examined using scanning electron microscopy. RESULTS: Presence of S. mutans 3,3, S. anginosus 2.1.b, S. dysgalactie 6.1.4.1, and E. faecium 10.2. was measured in the biofilm samples. The extracts showed a bacteriostatic effect on the test bacteria, and among the green tea extracts, the methanol extract was found to exhibit the highest efficacy against biofilm formation by S. mutans 3.3. CONCLUSION: Green tea extract showed good efficacy in controlling bacterial growth, and is recommended as a better-tasting alternative for daily oral hygiene due to a lack of known side effects.

Real-time polymerase chain reaction quantification of the salivary levels of cariogenic bacteria in patients with orthodontic fixed appliances.

AIM: The aim was to investigate the salivary detection frequencies and quantities of caries-associated bacteria from patients with orthodontic brackets. METHODS: Patients wearing orthodontic brackets (n = 40, mean age = 26 years) and healthy controls without brackets (n = 40, mean age = 17 years) were enrolled in the study. Saliva samples from each patient was collected. After DNA purification, target species comprising streptococci and a Lactobacillus species were detected and quantified from the samples using polymerase chain reaction (PCR) and real-time quantitative PCR. RESULTS: Detection frequencies did not differ between the orthodontic patients and the control subjects for any target species except for Streptococcus sobrinus, which showed significantly lower detection rates in orthodontic patients (p < .05). Lactobacillus casei and Streptococcus gordonii were found at the highest detection frequencies with both species being detected in 38 (95%) of the saliva samples of orthodontic patients. Similarly, L. casei and Streptococcus salivarius were the species with highest detection frequencies (35, 87.5%) in the control subjects. Real-time PCR revealed that Streptococcus mutans and S. salivarius quantities were significantly higher in orthodontic patients than in the control subjects (p < .05). CONCLUSIONS: Application of orthodontic brackets for 12 months leads to increased salivary levels of cariogenic bacteria and may serve as a potential risk factor for caries initiation.

An in vitro evaluation of the effects of nanoparticles on shear bond strength and antimicrobial properties of orthodontic adhesives: A systematic review and meta-analysis study.

INTRODUCTION: Biofilm accumulation around orthodontic brackets and composite is a common complication of orthodontic treatment. OBJECTIVE: A systematic review and meta-analysis were done to find out whether the association of nanoparticles with the orthodontic adhesives compromises its properties and whether there are exceptional nanoparticles exhibiting excellent antimicrobial potential against cariogenic bacteria along with remarkable mechanical properties. MATERIALS AND METHODS: Electronic databases were searched using the following keywords; orthodontic or orthodontics and antimicrobial or antibacterial and adhesive and nanoparticles and shear bond strength. Thirteen studies were included and meta-analysis was performed. RESULTS: The results indicated no drastic changes in mechanical properties (0.812, 95% CI [0.750, 0.861], P=0.000). The Ag-HA, Cur, Cur-ZnO, and TiO2 in concentration≥1% showed a statistically significant difference, where the control groups had higher shear bond strength. Nine studies assessed the antimicrobial properties of nanoparticles. 1 wt% Cu and 5 wt% TiO2 not only did not affect shear bond strength but also showed more antimicrobial activity against Streptococcus mutans. The analysis demonstrated the absence of heterogeneity (Q value=44.014; df (Q)=12; and I2=72.736) in shear bond strength of orthodontic adhesives with nanoparticles, with low risk of bias. CONCLUSIONS: Adding≤5 wt% antimicrobial nanoparticles to an orthodontic adhesive is less conducive to microbial growth than unmodified adhesive and does not influence bracket-enamel bond strength.

Hydrogel-Coated Dental Device with Adhesion-Inhibiting and Colony-Suppressing Properties.

Bacterial infection is the main cause of implantation failure worldwide, and the importance of antibiotics on medical devices has been undermined because of antibiotic resistance. Antimicrobial hydrogels have emerged as a promising approach to combat infections associated with medical devices and wound healing. However, hydrogel coatings that simultaneously possess both antifouling and antimicrobial attributes are scarce. Herein, we report an antimicrobial hydrogel that incorporates adhesion-inhibiting polyethylene glycol (PEG) and colony-suppressing chitosan (CS) as a dressing to combat bacterial infections. These two polymers have important environmentally benign characteristics including low toxicity, low volatility, and biocompatibility. Although hydrogels containing PEG and CS have been reported for applications in the fields of wound dressing, tissue repair, water purification, drug delivery, and scaffolds for bone regeneration, there still has been no report on the application of CS/PEG hydrogel coatings in dental applications. Herein, this biointerface shows superior activity in early-stage adhesion inhibition (98.8%, 5 h) and displays remarkably long-lasting colony-suppression activity (93.3%, 7 d). Thus, this novel nanomaterial, which has potential as a dual-functional platform with integrated antifouling and antimicrobial functions with excellent biocompatibility, might be used as a safe and effective antimicrobial coating in biomedical device applications.

Quantitative analysis of biofilm formation on labial and lingual bracket surfaces.

OBJECTIVES: To evaluate and compare the biofilm formation between labial and lingual orthodontic brackets. MATERIALS AND METHODS: Twenty patients with a mean age of 24 ± 8.8 who had received labial or lingual orthodontic treatment were enrolled in the study. Biofilm formation on 80 brackets was analyzed quantitatively with the Rutherford backscattering detection method. Five micrographs were obtained per bracket with views from the vestibule/lingual, mesial, distal, gingival, and occlusal aspects. Quantitative analysis was carried out with surface analysis software (ImageJ 1.48). Data were analyzed by Mann-Whitney U and Kruskal-Wallis tests (α = 0.05). RESULTS: Total biofilm formation was 41.56% (min 29.43% to max 48.76%) on lingual brackets and 26.52% (min 21.61% to max 32.71%) on labial brackets. Differences between the two groups were found to be significant. No difference was observed in intraoral location. The biofilm accumulation was mostly located on gingival, mesial, and distal surfaces for both groups. CONCLUSIONS: The biofilm accumulation on lingual orthodontic therapy was found to be more than labial orthodontic therapy.

Antibacterial Effects of Orthodontic Primer Harboring Chitosan Nanoparticles against the Multispecies Biofilm of Cariogenic Bacteria in a Rat Model.

INTRODUCTION: Microbial biofilm accumulation around orthodontic brackets and composite is a common complication of fixed orth-odontic treatment. This study assessed the antibacterial effects of orthodontic primer containing chitosan nanoparticles (CNPs) against the multispecies biofilm of cariogenic bacteria in а rat model. MATERIALS AND METHODS: Transbond XT orthodontic primer containing 0%, 1%, 5%, and 10% CNPs was experimentally prepared. The Wistar rats were randomly divided into four groups (n=7) of control (0% CNPs), 1%, 5% and 10% CNPs. The oral cavities of the rats were infected with cariogenic bacteria. After anesthetizing the rats, 1 drop (10 µL) of primer with different concentrations of CNPs was applied to their central incisor and light-cured for 20 seconds. Transbond XT orthodontic adhesive (2 × 2 mm) was applied on the primer. Another drop (10 µL) of primer was applied and light-cured for 40 seconds. The number of Streptococcus mutans, Streptococcus sanguinis, and Lactobacillus acidophilus colonies in the saliva of rats was quantified at 24 hours, 4 days and 7 days. RESULTS: Adding 1% (p=0.005), 5% (p<0.001) and 10% (p<0.001) of CNPs to orthodontic primer significantly reduced the S. mutans colony count at 24 hours compared with the control group. At 24 hours, the mean S. sanguinis colony counts in the 5% (p=0.04) and 10% (p=0.02) CNP groups were significantly lower than that in the control group. Also, at 4 and 7 days, the mean colony counts in the 5% and 10% CNP groups were significantly lower than that in the control group (p<0.05). At 24 hours and 4 days, the mean L. acidophilus colony count in the 10% CNP group was significantly lower than that in the control group (p<0.05). At 7 days, rats with failed adhesive showed a significantly higher count of all three bacteria compared with rats with adhesive (p<0.05). CONCLUSIONS: The addition of 5% CNPs to orthodontic primer significantly decreased the colony count of cariogenic bacteria in rats.

Microbial species associated with dental caries found in saliva and in situ after use of self-ligating and conventional brackets.

OBJECTIVES: Enamel demineralization is among the main topics of interest in the orthodontic field. Self-ligating brackets have been regarded as advantageous in this aspect. The aim of this study was to evaluate the break homeostasis in the oral environment and the levels of microorganisms associated with dental caries among the different types of brackets. MATERIAL AND METHODS: Twenty patients received two self-ligating brackets: In-Ovation®R, SmartClipTM, and one conventional GeminiTM. Saliva was collected before bonding (S0), 30 (S1) and 60 (S2) days after bonding. One sample of each bracket was removed at 30 and 60 days for the in situ analysis. Checkerboard DNA-DNA Hybridization was employed to evaluate the levels of microbial species as-sociated with dental caries. Data were evaluated by nonparametric Friedman and Wilcoxon tests at 5% significance level. RESULTS: The salivary levels of L. casei (p=0.033), S. sobrinus (p=0.011), and S. sanguinis (p=0.004) increased in S1. The in situ analyses showed alteration in S. mutans (p=0.047), whose highest levels were observed to the In-Ovation®R. CONCLUSIONS: The orthodontic appliances break the salivary homeostasis of microorganisms involved in dental caries. The contamination pattern was different between self-ligating and conventional brackets. The In-Ovation®R presented worse performance considering the levels of cariogenic bacterial species.

Comparison of intraoral biofilm reduction on silver-coated and silver ion-implanted stainless steel bracket material : Biofilm reduction on silver ion-implanted bracket material.

PURPOSE: The objective of this in situ study was to quantify the intraoral biofilm reduction on bracket material as a result of different surface modifications using silver ions. In addition to galvanic silver coating and physical vapor deposition (PVD), the plasma immersion ion implantation and deposition (PIIID) procedure was investigated for the first time within an orthodontic application. MATERIALS AND METHODS: An occlusal splint equipped with differently silver-modified test specimens based on stainless steel bracket material was prepared for a total of 12 periodontally healthy patients and was worn in the mouth for 48 h. The initially formed biofilm was fluorescently stained and a quantitative comparative analysis of biofilm volume, biofilm surface coverage and live/dead distribution of bacteria was performed by confocal laser scanning microscopy (CLSM). RESULTS: Compared to untreated stainless steel bracket material, the antibacterial effect of the PIIID silver-modified surface was just as significant with regard to reducing the biofilm volume and the surface coverage as the galvanically applied silver layer and the PVD silver coating. Regarding the live/dead distribution, however, the PIIID modification was the only surface that showed a significant increase in the proportion of dead cells compared to untreated bracket material and the galvanic coating. CONCLUSIONS: Orthodontic stainless steel with a silver-modified surface by PIIID procedure showed an effective reduction in the intraoral biofilm formation compared to untreated bracket material, in a similar manner to PVD and galvanic silver coatings applied to the surface. Additionally, the PIIID silver-modified surface has an increased bactericidal effect.

Microbial species associated with dental caries found in saliva and in situ after use of self-ligating and conventional brackets

Abstract Objectives Enamel demineralization is among the main topics of interest in the orthodontic field. Self-ligating brackets have been regarded as advantageous in this aspect. The aim of this study was to evaluate the break homeostasis in the oral environment and the levels of microorganisms associated with dental caries among the different types of brackets. Material and Methods Twenty patients received two self-ligating brackets: In-Ovation®R, SmartClipTM, and one conventional GeminiTM. Saliva was collected before bonding (S0), 30 (S1) and 60 (S2) days after bonding. One sample of each bracket was removed at 30 and 60 days for the in situ analysis. Checkerboard DNA-DNA Hybridization was employed to evaluate the levels of microbial species as-sociated with dental caries. Data were evaluated by nonparametric Friedman and Wilcoxon tests at 5% significance level. Results The salivary levels of L. casei (p=0.033), S. sobrinus (p=0.011), and S. sanguinis (p=0.004) increased in S1. The in situ analyses showed alteration in S. mutans (p=0.047), whose highest levels were observed to the In-Ovation®R. Conclusions The orthodontic appliances break the salivary homeostasis of microorganisms involved in dental caries. The contamination pattern was different between self-ligating and conventional brackets. The In-Ovation®R presented worse performance considering the levels of cariogenic bacterial species.

Long-term antimicrobial assessment of orthodontic brackets coated with nitrogen-doped titanium dioxide against Streptococcus mutans.

BACKGROUND: The antimicrobial properties of orthodontic wire and brackets with nitrogen-doped titanium dioxide (N-doped TiO2) coating have been studied in the past. However, the evaluation period had been short and limited to 30 days. The aim of the present study was to extend the evaluation period (up to 90 days) of assessing the long-term antimicrobial effects of stainless steel orthodontic brackets coated with nitrogen-doped titanium dioxide (N-doped TiO2). METHODS: A total of 40 stainless steel pre-adjusted premolar brackets were equally divided into two groups; namely the control group (n=20, uncoated brackets) and the experimental group (n=20, coated brackets). RF magnetron sputtering was used to apply a thin film of TiO2 on the bracket surface. The crystalline structure of the thin film was assessed using X-ray diffraction. The antimicrobial property of the brackets against Streptococcus mutans (S. mutans) was evaluated using the survival rate by colony-forming units (CFU) at four intervals: 24 hours (T0), 30 days (T1), 60 days (T2), and 90 days (T3). 2-way ANOVA Repeated Measures was used to compare the effects between the groups over the time. RESULTS: There was no significant interaction between group and time (p = 0.568). The orthodontic brackets coated with the N-doped TiO2 thin film showed a significant CFU reduction (37.71 ± 5.21, 37.81 ± 5.03, 37.98 ± 5.37, and 37.74 ± 5.21 at T0, T1, T2, and T3, respectively) compared to the uncoated brackets (400.91 ± 14.67, 401.58 ± 14.01, 400.31 ± 14.68, and 402.04 ± 13.98 at T0, T1, T2, and T3, respectively) through visible light (p < 0.001). CONCLUSION: N-doped TiO2 coated orthodontic brackets showed strong antimicrobial property against S. mutans over a period of 90 days, which is effective in preventing enamel decalcification during orthodontic therapy.

Salivary Markers and Microbial Flora in Mouth Breathing Late Adolescents.

OBJECTIVE: This is a 6-month observational case-control study that aims to estimate plaque index (PI), salivary flow, buffering capacity of saliva, and specific Streptococcus mutans (S. mutans) and Lactobacillus rates in a mouth breathing late adolescents sample, after a professional oral hygiene procedure and home oral hygiene instructions. SUBJECTS AND METHODS: A sample of 20 mouth breathing late adolescents/young adults (average: 19.2 ± 2.5; range: 18-23 years) and a matched control group of nose breathing subjects (average: 18.3 ± 3.2; range 18-23 years) were included in the study. All the participants were subjected to a professional oral hygiene procedure and appropriate home oral hygiene instructions (t0). After three months (t1) and six months (t2), the PI, salivary flow, buffering capacity of saliva, and S. mutans and Lactobacilli rates were recorded. RESULTS: The mean buffering capacity of saliva and the salivary flow rate showed no significant difference between the two groups, all over the observational period. For PI, a significantly higher mode (score 1 of PI) was observed in the study group at t1 (score 0 = 35% of subjects; score 1 = 60%; score 2 = 5%) and t2 (score 1 = 65% of subjects, score 2 = 35%), with respect to control group. Furthermore, mouth breathing subjects show a significant 4 times higher risk to develop S. mutans CFU > 105 (CI lower limit: 0.95; CI upper limit: 9.48; chi-square: 4.28; p = 0.03), with respect to the control subjects. CONCLUSIONS: Mouth breathing late adolescents show a significantly higher risk to develop S. mutans CFU > 105 and an increased level of PI. Interceptive orthodontic treatments in growing subjects, like palatal expansion, are encouraged to improve the nasal air flow. In older subjects, orthodontic treatments should be performed with removable appliances like clear aligners, in order to allow a better oral hygiene level.

Comparing the periodontal clinical effect between conventional and self-ligating brackets: systematic review and meta-analysis

Introduction: orthodontists constantly seek to reduce the duration of their provided treatments and the patient's time in the office. for this reason, different bracket systems are currently used in orthodontics; an example is self-ligating brackets (SLB) which are believed to offer advantages over conventional brackets (CB). objective: to evaluate and compare the clinical periodontal effect of CB and SLB through a systematic review and a meta-analysis. material and method: a search of the literature was carried out until December 2017, in the biomedical databases: PubMed, Embase, SciELO, ScienceDirect, SIGLE, LILACS, BBO, Google Scholar and the Cochrane Central Register of Controlled Trials. the selection criteria of the studies were defined as such: randomized clinical trials, up to 5 years old and that report the clinical effects (probing depth, bleeding on probing, gingival index and plaque index) from the use of CB and SLB. the risk of study bias was analyzed through the Cochrane Handbook of systematic reviews of interventions. results: the search strategy resulted in 12 articles, eight of which reported no difference in the reduction in probing depth, bleeding on probing, gingival index and plaque index (p>0.05) between CB and SLB. conclusion: the literature reviewed suggests that there are no differences in the periodontal clinical effect among patients who received orthodontic treatment with CB or SLB.

Protein-mediated anti-adhesion surface against oral bacteria.

Biomedical materials, such as orthopedic biomaterials, have a great impact on improving life quality and self-esteem of human beings. However, the usage of fixed appliances during dental treatment often increases the difficulty of oral cleaning and enlarges the adhesion opportunity of oral bacteria. Furthermore, the existing anti-adhesion coatings, such as polyethylene glycol derivatives and zwitterionic polymers, have not been universally accepted in the oral environment due to their intrinsic problems. Herein, inspired by the anti-adhesion capability of bovine serum albumin, we report a facile protein-based anti-bacterial surface, showing excellent anti-adhesion performance toward oral bacteria. This protein-mediated anti-adhesion strategy may provide a promising clue for developing new anti-bacterial biomaterials, such as dental fixed appliances, restorative materials and medical mouthwashes.