Enamel Demineralization Research Articles

Antibacterial Activity of a Lysin LysP53 against Streptococcus mutans.

Dental caries is a common disease affecting quality of life globally. In the present study, we found that a bacteriophage lysin LysP53 against Acinetobacter baumannii possesses selective activity on Streptococcus mutans, the main etiological agent of dental caries, even in low pH caries microenvironments, whereas only minor LysP53 activity was detected against Streptococcus sanguinis, Streptococcus oralis, and Streptococcus mitis. Testing activity against S. mutans planktonic cells showed that 4 μM LysP53 could kill more than 84% of S. mutans within 1 min in buffer with optimal pHs ranging from 4.0 to 6.5. Daily application of LysP53 on biofilms formed in BHI medium supplemented or not with sucrose could reduce exopolysaccharides, expression of genes related to acid resistance and adhesion, and the number of live bacteria in the biofilms. LysP53 treatment also showed similar effects as 0.12% chlorhexidine in preventing enamel demineralization due to S. mutans biofilms, as well as effective removal of S. mutans colonization of tooth surfaces in mice without observed toxic effects. Because of its selective activity against main cariogenic bacteria and good activity in low pH caries microenvironments, it is advantageous to use LysP53 as an active agent for preventing caries.

Comparison of microleakage under orthodontic brackets bonded with five different adhesive systems: in vitro study

BackgroundOrthodontic treatment is associated with numerous adverse side effects, such as enamel discoloration, demineralization or even caries. The presence of microleakage between the enamel and the adhesive and between the adhesive and the base of the orthodontic bracket allows penetration of the bacteria, molecules, and liquids into the enamel and can lead to unpleasant “white spot lesions” or secondary caries beneath and around the brackets. The aim of this in vitro study was to evaluate microleakage in five adhesive systems commonly used in orthodontic practice for bonding brackets.MethodsOne hundred extracted premolars were divided into five groups of twenty teeth. Stainless steel Legend medium metal brackets were bonded to teeth using five adhesive systems: resin-reinforced glass ionomer cement GC Fuji Ortho LC (GCF) and composite materials Light Bond (LB), Transbond XT (TB), Trulock™ Light Activated Adhesive (TL), and GC Ortho Connect (GCO). The specimens were subjected to thermal cycling, stained with 2% methylene blue, sectioned with low–speed diamond saw Isomet and evaluated under a digital microscope. Microleakage was detected at the enamel-adhesive and adhesive-bracket interfaces from occlusal and gingival margins. Statistical analysis was performed using generalized linear mixed models with beta error distribution.ResultsMicroleakage was observed in all materials, with GCF showing the highest amount of microleakage. Composite materials GCO, TB, and LB exhibited the lowest amount of microleakage with no statistical difference between them, while TL showed a statistically significantly higher amount of microleakage (p < 0.001). The enamel–adhesive interface had more microleakage in all composite materials (GCO, LB, TB, and TL) than the adhesive bracket–interface (p < 0.001). The highest amount of microleakage occurred in the gingival region in all materials.ConclusionComposite materials showed better adhesive properties than a resin-reinforced glass ionomer cement. The presence of microleakage at the enamel-adhesive interface facilitates the penetration of various substances into enamel surfaces, causing enamel demineralization and the development of dental caries.

Relationship between dentifrices based on hydroxyapatites and human enamel remineralization

Enamel demineralization is an intricate process that holds significant clinical consequences, being a central part of the emergence and progression of various dental problems, most notably dental caries. This demineralization of tooth enamel is linked to a variety of factors, including the composition of oral microbiota and that of saliva, the prevalence of sugar consumption or acidic soft drinks, and, of course, oral hygiene practices. The oral microbiome plays a role in generating organic acids that foster an environment conducive to enamel breakdown. Additionally, a decrease in saliva production can lower the oral environment’s ability to neutralize acids and support the remineralization process, thereby intensifying demineralization. Dentifrices enriched with biomimetic hydroxyapatites are important in preventing demineralization as they not only help with oral hygiene but also provide key ions that help strengthen enamel. Considering their similarity to the natural component in enamel, synthetic hydroxyapatites have recently emerged as potent remineralizing agents. Hence, this work aims to illustrate in a simple and concise manner, some of the aspects involved in enamel demineralization and its subsequent remineralization, namely in the relationship between enriched toothpastes containing biomimetic hydroxyapatites and their remineralization eficacy.

Influence of Sucrose and Arenga pinnata Solutions on Enamel Surface Demineralization: A Profilometric Study.

Background Dental caries is a multifactorial disease that has the potential to impact individuals across various life stages. The influential role of sugar as a contributing risk element in the inception and advancement of dental caries is significantly pronounced. Aim The research aim was to analyze and compare the enamel surface roughness in teeth exposed to sucrose and Arenga pinnata (palm sugar) solutions by using a stylus profilometer Materials and methods In this investigation, 34 freshly extracted anterior teeth were obtained and they were split into two groups depending on the solution in which they were immersed. Group A consists of 17 teeth immersed in 1% sucrose solution supplemented in brain heart infusion(BHI) broth solution and Group B consists of 17 teeth immersed in 1% Arenga pinnataBHIbroth. Each sample served as its own control. Streptococcus mutans was inoculated into these groups and they were immersed in their respective solution for five days. A stylus profilometer was utilized to measure the surface roughness of the teeth in this study. Data analysis involved paired t-tests for intragroup comparisons and independent t-tests for intergroup comparisons using SPSS software version 23. Results After five days of exposure to palm sugar or sucrose, it was observed that there was demineralization of the enamel surface on both samples. Although there was no statistical significance (p<0.05) when an independent t-test was conducted among these samples, there was a visible increase in the numerical values of Ra, Rq, Rz of teeth exposed to sucrose compared to palm sugar with a p-value of 0.529, 0.122 and 0.357, respectively. Conclusion From this study, it was concluded that although both sucrose and Arenga pinnata causedemineralization of enamel, it was shown that the latter caused lesser demineralization when compared to refined sugars to a certain extent. This study establishes a foundation for forthcoming investigations that could potentially explore the utilization of natural sugars as a substitute for sucrose, while also evaluating the mechanistic aspects underlying the impact of these sugars on enamel demineralization.

The Effect of Two Types of Erbium Laser and Light Cure Fluoride Varnish on Enamel Demineralization and Surface Microhardness around Metal Orthodontic Brackets: An in-Vitro study

The Effect of Two Types of Erbium Laser and Light Cure Fluoride Varnish on Enamel Demineralization and Surface Microhardness around Metal Orthodontic Brackets: An in-Vitro study

Effectivity of Calcium, Phosphate and Vitamin D in Dental Caries Prevention

Background: Micronutrient elements are vitamins and minerals that are required in small amounts but play important roles in our body. Insufficient micronutrients can affect health including dental health. Objective: Analyzing effectiveness of micronutrients (calcium, phosphorus, and vitamin D) in preventing dental caries. Literature study: This literature study was conducted from Google Scholar, Science Direct, and Pubmed (MEDLINE). The strategy used in literature collection is in the form of writing keywords that are used to find articles to be reviewed with a publication period between 2012 - 2020. Discussion: Dental caries is a demineralization of an inorganic part of the tooth due to a multifactorial etiology and occurs when demineralization exceeds remineralization. The calcium and phosphorus ions level in the saliva could affect the balance between demineralization and remineralization of enamel and its deficiency can strongly influence morphology of the tooth. It has been found that calcium level significantly influences hard dental tissues defense mechanisms. On the other side, vitamin D also plays an important role to form enamel and dentin in the tooth development process because of its receptor in ameloblasts and odontoblasts. Deficiency of vitamin D can cause enamel hypoplasia which is a significant factor for early childhood caries. Conclusions: Calcium, phosphorus, and vitamin D significantly affecting the demineralization and remineralization process. The optimum concentration and level of calcium, phosphorus, and vitamin D in the body effectively increase the tooth defense mechanism and reduce the dental caries.

Acceleration Techniques for Teeth Movements in Extractive Orthodontic Therapy

For a world that is constantly trying to speed up every procedure while obtaining the maximum result, traditional orthodontics have the biological limitation of using light and constant forces that allow tooth movement in a time frame that is only sometimes short. The treatment time could be lengthened if surgical procedures are programmed in the plan. Methods to accelerate tooth movement and reduce the duration of treatment while minimising complications are investigated and reported in the dental literature (e.g., low-level laser therapy, corticotomy, and micro-osteoperforations). This systematic review aims to analyse and summarise the strategies for quickening orthodontic movement during extraction orthodontic treatment, including any potential drawbacks or adverse consequences. The review will evaluate each approach’s effectiveness, safety, and evidence quality, compare their benefits and disadvantages, and analyse the implications for clinical practice and future research. Pubmed, Science Direct, Scopus, and Web of Science were searched using the keywords “acceleration” AND “dental movement” AND “orthodontic” between 1 April 2003 and 1 April 2023. After carefully scanning the study findings, forty-four publications were chosen for the systematic review. Most therapies discussed and provided in the literature seem promising and successful in enhancing orthodontic treatments. The success of operations like corticotomies, piezo-incisions, micro-osteoperforations, osteogenic distraction, low-level laser therapy, the administration of pharmacological treatments, and infiltrations with PRF and PRP were statistically significant and appear to be promising and effective in optimising orthodontic treatments. These strategies expedite treatment and enhance the patient experience, potentially broadening orthodontic appeal and minimising issues like cavities and enamel demineralisation. Further studies, with larger samples and standardised treatment protocols, are needed to investigate the efficacy of these tooth movement acceleration modalities.

In vitro evaluation of a novel fluoride-coated clear aligner with antibacterial and enamel remineralization abilities.

To investigate the antibacterial and enamel remineralization performances as well as physicochemical properties and biocompatibility of a fluoride-coated clear aligner plastic (FCAP). FCAP and normal clear aligner plastic (CAP) was bought from the manufacturer (Angelalign Technology Inc, China). The FCAP was observed under scanning electron microscopy. Its element composition, resistance to separation, contact angle, and protein adhesion performance were characterized. Colony-forming unit (CFU) count and 3-(4,5)-dimethylthiazol(-z-y1)-3,5-diphenyltetrazolium bromide (MTT) assay were used to evaluate the antibacterial ability of Streptococcus mutans. Fluoride release-recharge patterns were obtained. Apatite formation was evaluated after immersing FCAP in artificial saliva. Enamel remineralization capability was evaluated in the demineralization model (immersing samples in demineralization solution for 36h) and pH cycling model (immersing samples in demineralization solution and remineralization solution in turns for 14days). Cell Counting Kit-8 (CCK-8) and live/dead cell staining kits were used for cytotoxicity assay. The FCAP showed uniformly distributed fluoride and did not compromise protein adhesion performance. CFU count (5.47 ± 0.55 for CAP, 3.63 ± 0.38 for FCAP) and MTT assay (0.41 ± 0.025 for CAP, 0.28 ± 0.038) indicated that the FCAP had stronger antibacterial activity compared with normal CAP (P < 0.05 for both evaluations). The FCAP could release fluoride continuously for 14days and could be recharged after immersing in NaF solution. The FCAP could induce the formation of hydroxyapatite in artificial saliva and could reduce the microhardness decrease, color change, and mineral loss of enamels in both two models (P < 0.05 for all evaluations). CCK-8 and live/dead cell staining analyses showed that the coating did not compromise the biocompatibility of the clear aligner (P > 0.05 for CCK-8 evaluation). The FCAP had antibacterial, fluoride recharge, and enamel remineralization abilities while it did not compromise physicochemical properties and biocompatibility. The FCAP has the potential to prevent enamel demineralization during clear aligner treatment.

Differences in enamel surface hardness between soaking carbonated drinks and application of duck eggshell paste remineralization material

ABSTRACTIntroduction: The surface hardness of enamel is affected by demineralization and remineralization of enamel. Demineralization can cause the enamel surface hardness to decrease. Carbonated drinks are acidic drinks which can lower the pH of the oral cavity and cause damage to the enamel. Lost tooth minerals can be restored with remineralizing materials, one of which contains calcium. Natural materials that can help remineralization are calcium carbonate (CaCO3) which can be found in several animal shells such as marine materials, pearl snails and eggshells. Duck eggshell is one of the household wastes which is high in calcium which consists of 94% calcium carbonate. The purpose of this study is to analyze differences in enamel surface hardness between soaking carbonated drinks and application of duck eggshell paste remineralization material. Methods: This type of research is a true experimental laboratory with a pretest-posttest research design with control group design. The study sample was 8 post-extraction premolars that matched the inclusion criteria. The samples were divided into two groups which were previously soaked in carbonated drinks for 15 minutes. Group I: duck eggshell paste and group II: pasta without duck eggshell which was applied for 3 minutes 2 times a day for 14 days. Hardness measurement using Vickers hardness tester. Results: based on data analysis using paired t-test. Enamel surface hardness after immersion in carbonated drinks (mean=327.50 SD=23.33). The enamel surface hardness increased after application of duck eggshell paste (mean=467.50, SD=14.15) p=0.001. The control group also increased after the application of pasta without duck eggshell (mean=429.40 SD=29.01) p=0.002. Conclusion: There is a difference in the hardness of the enamel surface after being soaked in carbonated drinks and after the application of duck egg shell paste. KEYWORDSdemineralization, enamel surface hardness, carbonated drinks, duck egg shell paste, remineralization.

Quantitative light-induced fluorescence enables effective detection of orthodontic adhesive residues in diverse environments

BackgroundAdhesive remnants post-orthodontic treatment might have deleterious effects on oral health, including enamel demineralization, plaque accumulation, and elevated risk of caries development. The aim of this study was to identify and characterize adhesive residues in an ex vivo environment rich in salivary microbiota using quantitative light-induced fluorescence (QLF) technology. MethodsDisc-shaped adhesive samples with thickness ranging from 800 to 100 µm were prepared using GC Ortho, GOTO, T Orthobond, and Transbond XT and subsequently evaluated utilizing a QLF system. Bovine teeth containing GC Ortho and GOTO adhesives and isolated human premolar teeth bonded with brackets were subjected to a 10-day incubation in an artificial saliva environment. Daily imaging was conducted using QLF during incubation. Data with ΔR > 30% and simple hygiene score (SHS) were obtained with a software for further analysis. ResultsFluorescence intensity exhibited significant differences among the four orthodontic adhesives (p < 0.05). Results of incubation in artificial saliva revealed that red fluorescence surrounding the adhesive on the tooth surface was distinctly observable from day five onwards, with ΔR > 30% and SHS levels higher than those of the control group without adhesive (p < 0.05). Observation of fluorescence images of isolated human premolar teeth with bonded brackets indicated that red fluorescence was primarily present around the brackets. ConclusionsApplication of QLF is efficacious in identifying and demarcating adhesive residues within an environment rich in salivary microbiota.

Tooth enamel demineralization in children during treatment with aligners: impact of oral hygiene and oral fluid pH (a pilot study)

Tooth enamel demineralization in children during treatment with aligners: impact of oral hygiene and oral fluid pH (a pilot study)

Antibacterial, antibiofilm and anticaries effect of BioXtra® mouthrinse for head and neck cancer (HNC) patients under a microcosm biofilm model

Background and purposeConsidering the lack of studies investigating salivary substitutes to control post-radiation caries for patients with head and neck cancer (HNC), this study aimed to evaluate the antibacterial, antibiofilm, and anticaries effects of BioXtra® on the microcosm biofilm formed on different enamel types (non-irradiated and irradiated) and from distinct saliva sources (control and HNC patients). Materials and methodsNon-irradiated and irradiated enamel specimens were treated with BioXtra®, phosphate-buffered-saline (PBS; negative control), or 0.12% chlorhexidine (CHX; positive control) for 1 min. Biofilm was produced from human saliva (healthy participants with normal salivary flow for the control group or irradiated HNC patients with hyposalivation for the HNC group), mixed with McBain saliva, under 0.2% sucrose exposure, daily submitted to the treatments (1 min), for 5 days. Bacterial metabolic activity, biofilm viability, CFU counting, and enamel demineralization were determined. ResultsBioXtra® significantly reduced the bacterial metabolic activity for both enamel types and the inoculum sources, being more effective for the irradiated enamel or for the saliva from the control group. Similarly, BioXtra® significantly reduced the biofilm viability, the CFU for total microorganisms, mutans streptococci, and lactobacilli, and was able to significantly reduce the mineral loss and the lesion depth compared to PBS. CHX was an effective treatment to significantly reduce all parameters, performing better than BioXtra® and reinforcing its reliable efficiency as a positive control. ConclusionRegardless of the enamel type and the inoculum source, BioXtra® presented antibacterial, antibiofilm, and anticaries effects under this experimental model, which should be confirmed in further clinical studies.

Effect of Three Different Remineralizing Agents on In Vitro Enamel Demineralization: Using Vickers Hardness Test and SEM-EDX

Effect of Three Different Remineralizing Agents on In Vitro Enamel Demineralization: Using Vickers Hardness Test and SEM-EDX

Multi-resolution Correlative Ultrastructural and Chemical Analysis of Carious Enamel by Scanning Microscopy and Tomographic Imaging.

Caries, a major global disease associated with dental enamel demineralization, remains insufficiently understood to devise effective prevention or minimally invasive treatment. Understanding the ultrastructural changes in enamel is hampered by a lack of nanoscale characterization of the chemical spatial distributions within the dental tissue. This leads to the requirement to develop techniques based on various characterization methods. The purpose of the present study is to demonstrate the strength of analytic methods using a correlative technique on a single sample of human dental enamel as a specific case study to test the accuracy of techniques to compare regions in enamel. The science of the different techniques is integrated to genuinely study the enamel. The hierarchical structures within carious tissue were mapped using the combination of focused ion beam scanning electron microscopy with synchrotron X-ray tomography. The chemical changes were studied using scanning X-ray fluorescence (XRF) and X-ray wide-angle and small-angle scattering using a beam size below 80 nm for ångström and nanometer length scales. The analysis of XRF intensity gradients revealed subtle variations of Ca intensity in carious samples in comparison with those of normal mature enamel. In addition, the pathways for enamel rod demineralization were studied using X-ray ptychography. The results show the chemical and structural modification in carious enamel with differing locations. These results reinforce the need for multi-modal approaches to nanoscale analysis in complex hierarchically structured materials to interpret the changes of materials. The approach establishes a meticulous correlative characterization platform for the analysis of biomineralized tissues at the nanoscale, which adds confidence in the interpretation of the results and time-saving imaging techniques. The protocol demonstrated here using the dental tissue sample can be applied to other samples for statistical study and the investigation of nanoscale structural changes. The information gathered from the combination of methods could not be obtained with traditional individual techniques.

Effect of polydopamine and fluoride ion coating on dental enamel remineralization: an in vitro study

BackgroundFluoride treatment is one of the most effective dental caries prevention methods. To continuously prevent dental caries, stably immobilizing the fluoride on the tooth enamel is highly desirable. This study aimed to evaluate the remineralization of tooth enamels by one-pot coating using polydopamine and fluoride ions.MethodsTo prepare the enamel specimens for polydopamine- and fluoride ion-coating, they were treated with polydopamine- and fluoride-containing gels. The enamel specimens were collected from human molars in a blind manner (n = 100) and were randomized into five treatment groups (n = 20, each): 1) untreated, 2) polydopamine-coated, 3) fluoride-containing gel-treated, 4) F varnish-treated, and 5) polydopamine- and fluoride ion-coated enamels. Vickers hardness number (VHN), morphology, and fluoride contents of the specimens were measured before and after the pH-cycling regimen.ResultsPolydopamine- and fluoride ion-coated enamels showed the highest fluoride content and lowest VHN reduction among the samples. The fluoride content of the polydopamine/fluoride ion (PD/F)-coated enamel was increased to 182 ± 6.6%, which was far higher than that of the uncoated enamel (112.3 ± 32.8%, P < 0.05). The changes in the VHN values (ΔVHN) of PD/F-coated enamel substrates showed a slight reduction in the VHN (-3.6%, P < 0.05), which was far lower than that in the control group (-18.9%, P < 0.05). In addition, scanning electron microscopy clearly supported the effect of polydopamine- and fluoride ion-coatings on the remineralization of enamel specimens.ConclusionOur findings suggest that one-pot treatments with polydopamine and fluoride ions could significantly enhance remineralization by inhibiting enamel demineralization through the prolonged retention of fluoride ions.

Evaluation of the Prevalence of White Spot Lesions During Fixed Orthodontic Treatment Among Patients Reporting for Correction of Malocclusion: A Prevalence Study.

Despite recent breakthroughs in caries preventive measures, one of the biggest issues clinicians confront is preventing demineralization while undergoing orthodontic therapy. The buildup of plaques around orthodontic brackets over time causes white spot lesions (WSLs). The goal of the present research was to assess the prevalence of WSLs in patients undergoing orthodontic treatment before starting therapy and at six and 12 months into therapy, adopting the visual examination approach. We looked for WSLs on tooth surfaces gingival to an archwire because this is the area most likely to experience enamel demineralization during orthodontic treatment. The visual assessment was conducted using the following scale at baseline, six months, and 12 months for orthodontic patients: score 0: no demineralization or noticeable white patches on the surface; score 1: mild demineralization with a visible white spot but no surface disruption; score 2: moderate demineralization with a noticeable WSLthat has a roughened surface but does not need repair; and score 3: severe demineralization with a noticeable WSLthat needs repair.Fisher's exact test was used after a chi-square analysis to determine whether there were any differences between all three categories (six months, 12 months, and control). The frequency of WSL in patients at 12 months of orthodontic treatment was 46.57%, while it was 11.86% in patients who just started orthodontic treatment. The difference was statistically significant (p = 0.01), showing that the frequency was greater in patients at 12 months of orthodontic treatment as compared to patients who had just started undergoing orthodontic treatment. The frequency of WSL in patients at six months of orthodontic treatment was 37.34%, while it was 11.86% in patients who just started orthodontic treatment. The difference was statistically significant (p = 0.03), showing that the frequency was greater in patients at six months of orthodontic treatment as compared to patients who had just started undergoing orthodontic treatment. The frequency of WSL in patients at six months of orthodontic treatment was 37.34%, while it was 46.57% in patients at 12 months of orthodontic treatment. The frequency was greater in patients at 12 months of orthodontic treatment as compared to patients at six months of orthodontic treatment; however, the difference was non-significant statistically (p = 0.76). This clinical investigation revealed that the number of WSLs increased significantly during the first six months of treatment and then increased gradually until the final 12 months. During the first few months of treatment, doctors should assess the patients' dental hygiene habits and, if necessary, take further precautions to prevent demineralization.

Effect of Dental Varnishes in Prevention of Enamel Demineralization Adjacent to Orthodontic Brackets.

The aim of the current research was to assess the ability of different dental varnishes in averting enamel demineralization adjoining the orthodontic brackets. Seventy-five premolars devoid of dental caries that were subjected to extraction for orthodontic purposes were employed in this research. The surface of enamel was etched with 37% phosphoric acid and subjected to primer application. Individual brackets were placed on the midregion of the buccal surfaces of the premolars with Transbond™ XT adhesive. Postbracket bonding, the dry premolar tooth samples were set aside cautiously. The samples were then allocated to three groups: Group I: Duraphat Varnish, Group II: Clinpro XT Varnish, and Group III: Profluorid Varnish. Every sample was independently subjected to immersion in demineralizing solution for a period of 96 h at 37°C in an incubator. Areas of demineralization were evaluated by documenting the microhardness along the severed surface using a microhardness tester equipped with a Vickers diamond. The highest surface microhardness was noted with Profluorid Varnish group at 328.48 ± 1.12 in pursuit by Clinpro XT Varnish group at 322.08 ± 0.04 as well as Duraphat Varnish group at 307.42 ± 0.28 with a statistically noteworthy dissimilarity amid the groups. In conclusion, the three varnishes employed had an influence on the prevention of enamel demineralization surrounding the orthodontic brackets. Profluorid varnish however exhibited maximum efficiency in avoiding enamel demineralization versus Clinpro XT varnish as well as Duraphat varnish group.

Assessment of Enamel Demineralization Following the Use of Different Orthodontic Bracket Materials, Etchants, and Adhesive Systems: An In Vitro Study

The aim of this study was to assess enamel demineralization depth following the use of different bracket materials, etchants, and adhesive systems. Ninety-nine extracted human premolars were assigned to nine groups (eight experimental and one control), each including 11 specimens. The experimental groups were bonded to either metal or ceramic brackets and prepared using a total-or self-etchant with a pre-coated or flash-free adhesive system. All specimens were immersed in an artificial demineralization solution for 7 days at pH 4.5 and 37 °C. The brackets were debonded, and the specimens were sectioned buccolingually at the right and left sides of the bracket base margins. Scanning electron microscopy was used to assess the demineralization depth using ImageJ software. Significantly deeper enamel demineralization was observed in all bonded teeth compared to non-bonded teeth (p &lt; 0.001). The adhesive system had no significant effect on the demineralization depth. Metal brackets caused significantly deeper enamel demineralization than ceramic brackets (p &lt;0.005). The use of the total-etch surface treatment caused deeper demineralization compared to that of the self-etch treatment. In conclusion, bonded teeth exhibit deeper enamel demineralization than non-bonded teeth. Metal brackets contribute to deeper demineralization than ceramic brackets. The total-etch surface treatment caused deeper demineralization than self-etch when combined with metal brackets and a pre-coated adhesive system.

The Effect of Sub-MIC of Salvadora persica on Growth and Virulence Gene Expressions in Streptococcus mutans.

Dental caries is a multifactorial infectious chronic disease caused by particular bacteria and their virulence products that causes demineralization and progressive deterioration of the dental enamel. Many studies have proven miswak to have a critical antibacterial impact, particularly on cariogenic bacteria and periodontal pathogens, in the oral cavity. This study aimed to investigate the effect of different concentrations of Salvadora persica plant extract on growth and virulence gene expressions at mRNA levels in S. mutans. A total of 191 clinical samples from tooth swabs were collected, and sub-cultured on specific medium agar identified using biochemical and molecular approaches. MIC for the extract was determined and a bacterial growth curve was made to determine the growth phases and the optimum time for adding the extract at different concentrations. RT-qPCR technique was performed, and the REST-2009 software program was used for data analysis. Out of 191 swabs from the tooth 31 isolates were identified using several biochemical and molecular tests. Several S. mutans biofilm-related virulence genes and their Ct values were produced from RT-PCR under the effect of low and high doses of Meswak concentrations. Ct values and reaction efficiency were produced in RT-qPCR by Rotorgen3000, data then were analysed by REST-2009 software. Five isolates were selected to examine the effect of the extract on the mRNA levels using qPCR after growing them with both doses of the extract for about 30hrs. Levels of virulence gene mRNA were regulated differentially in cultures with added both extract doses. The isolates produced significantly lower virulence gene mRNA levels in cultures grown with both plant extract doses. The results produced in this study here provide new insights regarding several virulence gene expressions in S. mutans at the molecular levels when grown under different concentrations of Salvadora persica plant extract.

Comparison of enamel demineralization and periodontal status between direct and digital indirect bonding techniques : A split-mouth clinical trial of direct vs. digital indirect bonding.

This randomized clinical trial aimed to evaluate the effects of digital indirect bonding (DIB) compared to the direct bonding (DB) technique in terms of enamel demineralization and periodontal status. A total of 24patients (17females, 7males) with amean age of 13.83 ± 1.55years were bonded using DB and DIB techniques using asplit-mouth study design. Bonding techniques were randomly allocated to quadrants. Demineralization measurements were performed with the DIAGNOdent pen (Kavo, Biberach, Germany) from four sides (distal, gingival, mesial, and incisal/occlusal) of all brackets immediately after bonding, 1month (T1), and 6months (T2) after bonding. Periodontal measurements were taken before bonding and at the same time points (T1 and T2). Data were statistically analyzed with the Mann-WhitneyU test to determine possible differences between groups. Incisal/occlusal sides exhibited the lowest demineralization values at T2. The gingival side of upper centrals, mesial side of upper laterals, and distal sides of upper first premolar and lower laterals brackets bonded with the DIB technique exhibited significantly increased demineralization compared with the DB technique from T0 to T2 (p < 0.05). Periodontal parameters increased 1month after bonding and decreased during the follow-up. Bonding technique showed no statistically significant difference in plaque index, gingival index, and bleeding on probing values at any time interval. There were many locations around the brackets with significantly higher demineralization after 6months in patients who received digital indirect bonding compared to the DB group. Although periodontal health was generally adequate, complete removal of adhesive flash should be carefully carried out to decrease the risk of demineralization during indirect bonding technique with digital workflows.