Evaluation of enamel surface integrity after orthodontic bracket debonding: comparison of three different system.

OBJECTIVE: This study aimed to evaluate enamel surface integrity and time consumed during residual cement removal after bracket debonding using different adhesive removal burs with and without a dental loupe. MATERIAL AND METHODS: Sixty human-extracted premolars were collected, cleaned, mounted, and prepared for orthodontic bracket bonding. Teeth were randomly divided into three main groups (n = 20) based on the adhesive removal method: tungsten carbide system (TC), sof-lex discs system (SD), and diamond system (DB) groups. Then, each group was subdivided into two subgroups (naked eye and magnifying loupe subgroups). The brackets were bonded and then debonded after 24 h, and the Adhesive Remnant Index (ARI) was assessed. The adhesive remnants were removed by different systems, and the final polishing was performed by Silicone OneGloss. The enamel surface roughness was evaluated before bracketing (T0), after residual cement removal (T1), and finally after polishing (T2) using surface Mitutoyo SJ-210 profilometry and Scanning Electron Microscopy (SEM) to determine the Enamel Damage Index (EDI) score. The time consumed for adhesive removal was recorded in seconds. RESULTS: The Kruskal Wallis test showed a statistically significant difference in roughness values at T1 compared to T2 between subgroups (p < 0.001). When comparing EDI at T1 and T2, the Kruskal-Wallis H-test showed statistically significant differences in all subgroups. The pairwise comparisons revealed that EDI scores showed a statistically significant difference at T1 and T2 between DB vs. TC and SD (p = 0.015) but not between TC vs. SD (p = 1.000), indicating the highest roughness value observed in the DB group. The time for cement removal was significantly shorter in the magnifying loupe group than in the naked eye group and was shortest with the TC group, whereas the time was the longest with the DB group (p < 0.05). CONCLUSION: All three systems were clinically satisfactory for residual orthodontic adhesive removal. However, TC system produced the lowest enamel roughness, while the DB system created the greatest. The polishing step created smoother surfaces regardless of the systems used for resin removal.

Initial arch wires used in orthodontic treatment with fixed appliances.

BACKGROUND: Initial arch wires are the first arch wires inserted into fixed appliance at the beginning of orthodontic treatment. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which are most efficient and which cause the least amount of root resorption and pain during the initial aligning stage of treatment. This is the third update of a Cochrane review first published in 2010. OBJECTIVES: To assess the effects of initial arch wires for the alignment of teeth with fixed orthodontic braces, in terms of the rate of tooth alignment, amount of root resorption accompanying tooth movement, and intensity of pain experienced by patients during the initial alignment stage of treatment. SEARCH METHODS: We searched Cochrane Oral Health's Trials Register, CENTRAL, MEDLINE, Embase, and two ongoing trials registries on 4 July 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of different initial arch wires used to align teeth with fixed orthodontic braces. We included people with full-arch fixed orthodontic appliances on the upper arch, lower arch, or both arches. DATA COLLECTION AND ANALYSIS: Two independent review authors were responsible for study selection, data extraction, and assessment of risk of bias in included studies. We contacted corresponding authors of included studies to obtain missing information. We resolved disagreements by discussion between the review authors. Our main outcomes were alignment rate (movement of teeth in mm), root resorption, time to alignment, and intensity of pain measured on a 100-mm visual analogue scale (VAS). We pooled data from studies with similar interventions and outcomes using random-effects models. We reported mean differences (MDs) with 95% confidence intervals (CIs) for continuous data, risk ratios (RRs) with 95% CIs for dichotomous data, and alignment rate ratios with 95% CIs for time-to-event data. Two independent review authors assessed the certainty of evidence. We resolved disagreements by discussion between the review authors. MAIN RESULTS: We included 29 RCTs with 1915 participants (2581 arches) in this review. Studies were generally small (sample sizes ranged from 14 to 200 participants). Duration of follow-up varied between three days and six months. Eleven studies received funding, six received no funding, and 12 provided no information about funding sources. We judged eight studies at high risk of bias, nine at low risk, and 12 at unclear risk. We grouped the studies into six main comparisons. Multistrand stainless steel wires versus wires composed of other materials Six studies with 409 participants (545 arches) evaluated multistrand stainless steel (StSt) wires versus wires composed of other materials. We are very uncertain about the effect of multistrand StSt wires versus other wires on alignment rate (4 studies, 281 participants, 417 arches; very low-certainty evidence). There may be little to no difference between multistrand StSt wires and other wires in terms of intensity of pain (MD -2.68 mm, 95% CI -6.75 to 1.38; 2 studies, 127 participants, 127 arches; low-certainty evidence). Conventional nickel-titanium wires versus superelastic nickel-titanium wires Four studies with 266 participants (274 arches) evaluated conventional nickel-titanium (NiTi) wires versus superelastic NiTi wires. There may be little to no difference between the different wire types in terms of alignment rate (124 participants, 124 arches, 2 studies; low-certainty evidence) and intensity of pain (MD -0.29 mm, 95% CI -1.10 to 0.52; 2 studies, 142 participants, 150 arches; low-certainty evidence). Conventional nickel-titanium wires versus thermoelastic copper-nickel-titanium wires Three studies with 210 participants (210 arches) evaluated conventional Ni-Ti versus thermoelastic copper-nickel-titanium (CuNiTi) wires. We are very uncertain about the effects of the different arch wires on alignment rate (1 study, 66 participants, 66 arches; very low-certainty evidence). There may be little to no difference between conventional NiTi wires and thermoelastic CuNiTi wires in terms of time to alignment (alignment rate ratio 1.30, 95% CI 0.68 to 2.50; 1 study, 60 participants, 60 arches; low-certainty evidence). Superelastic nickel-titanium wires versus thermoelastic nickel-titanium wires Twelve studies with 703 participants (936 arches) evaluated superelastic NiTi versus thermoelastic NiTi wires. There may be little to no difference between superelastic NiTi wires and thermoelastic NiTi wires in alignment rate at four weeks (MD -0.28 mm, 95% CI 0.62 to 0.06; 5 studies, 183 participants, 183 arches; low-certainty evidence). We are very uncertain about the effects of the different wires on root resorption (2 studies, 52 participants, 312 teeth; very low-certainty evidence). Superelastic NiTi wires compared with thermoelastic NiTi wires may result in a slight increase in time to alignment (MD 0.5 months, 95% CI 0.21 to 0.79; 1 study, 32 participants, 32 arches; low-certainty evidence) but are probably associated with a slight increase in intensity of pain (MD 6.96 mm, 95% CI 1.82 to 12.10; 3 studies, 94 participants, 138 arches, moderate-certainty evidence). Single-strand superelastic nickel-titanium wires versus coaxial superelastic nickel-titanium wires Three studies with 104 participants (104 arches) evaluated single-strand superelastic NiTi versus coaxial superelastic NiTi wires. Use of single-strand superelastic NiTi wires compared with coaxial superelastic NiTi wires probably results in a slight reduction in alignment rate at four weeks (MD -2.64 mm, 95% CI -4.61 to -0.67; 2 studies, 64 participants, 64 arches, moderate-certainty evidence). Different sizes of nickel-titanium wires Two studies with 149 participants (232 arches) compared different types of NiTi wires. There may be little to no difference between different sizes of NiTi wires in terms of pain (low-certainty evidence). AUTHORS' CONCLUSIONS: Superelastic NiTi wires probably produce slightly more pain after one day than thermoelastic NiTi wires, and single-strand superelastic NiTi wires probably have a lower alignment rate over four weeks compared with coaxial superelastic NiTi wires. All other evidence on alignment rate, root resorption, time to alignment, and pain is of low or very low certainty in all comparisons. Therefore, there is insufficient evidence to determine whether any particular arch wire material or size is superior to any other. The findings of this review are imprecise and unreliable; well-designed larger studies are needed to give better estimates of the benefits and harms of different arch wires. Orthodontists should exercise caution when interpreting the findings of this review and be prepared to adapt their treatment plans based on individual patient needs.

In-vitro effect of a single application of CPP-ACP pastes and different fluoridated solutions on the prevention of dental caries around orthodontic brackets.

OBJECTIVE: To assess the in-vitro effect of single applications of CPP-ACP pastes and different fluoridated solutions on the prevention of dental caries around orthodontic brackets. MATERIAL AND METHODS: Tooth/bracket sets (n=65) were immersed in artificial saliva (1h at 37ºC) and randomly subjected to single applications (100µL; 1min) of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP emulsion), CPP-ACP with fluoride (CPP-ACPF emulsion), solutions of titanium tetrafluoride (TiF4) or sodium fluoride (NaF), or no treatment (CG). Multispecies biofilm (5 x 105 CFU/mL) was formed in the presence of 2% sucrose. After 24 h, the pH and the concentration of total soluble fluoride (TSF) were analyzed by culture medium. The presence of active white spot lesions (WSL) evaluated by macroscopic examination and the percent surface mineral loss (%SML) were analyzed. Also, the topography of enamel was detected by analysis of scanning electron microscopy (SEM). The data was assessed by chi-square, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). RESULTS: Fluoride-containing compounds led to a smaller pH reduction than did CPP-ACP and CG (p<0.05). There was difference in TSF between the groups (p<0.05), denoted as TiF4> NaF > CPP-ACPF > CPP-ACP > CG. Regarding the presence of WSL and %SML, the NaF group obtained lower values (p<0.05), while TiF4 and CPP-ACPF were similar (p>0.05). SEM demonstrated that fluoride-free groups had a larger surface dissolution. CONCLUSION: Fluoridated groups including solutions and CPP-ACPF were more effective than CPP-ACP in reducing enamel demineralization around orthodontic brackets after a single application.

White spot lesions after fixed appliance treatment-Can we expect spontaneous long-term (≥15 years) improvement?

OBJECTIVE: To investigate the extent to which post-orthodontic white spot lesions (WSLs) change in appearance over a period of ≥15 years and whether an association with caries data exists. SUBJECTS AND METHODS: Seventy-two patients treated with a Herbst-Multibracket appliance at age 14.0 ± 2.7 years for 20.1 ± 5.1 months who attended a recall 18.3 ± 2.9 years post-treatment. Post-treatment (T1) intraoral photographs were assessed by a panel of five dentists using a modified version of the WSL-Index by Gorelick. For affected incisors, photographs from before treatment (T0) and recall (T3) were evaluated. In addition, the WSL-Change Index by Pancherz and Muehlich was assessed for all adequately visible incisors considering T1, T2 (if available), and T3. Radiographic (T0, T1, and T2-if available) and clinical (T3) MFT data were used. RESULTS: 37.5% of the patients exhibited WSLs on ≥ 1 incisor at T1; in total, 81 incisors (14.9%) were affected. At T3, 48% of the WSLs had improved. The modified WSL-Index decreased from 1.2 ± 0.4 to 0.8 ± 0.6 (P < .001), with a score 0 in 28% of the previously affected incisors. When comparing T2 vs. T3, additional improvement after T2 occurred in 11% of the teeth. While no difference existed at T0, the MFT values at T1, T2, and T3 were higher (P ≤ .05) in patients with WSLs at T1 than in those without. LIMITATIONS: The homogeneity of the subjects was limited and no patient-reported outcome was assessed. CONCLUSIONS: Long-term, post-orthodontic WSLs showed spontaneous full recovery in 28% and improvement in 48% of the teeth. Patients affected with WSLs exhibited higher post-treatment MFT values.

Effect of chewing gum on orthodontic pain in patients receiving fixed orthodontic treatment: a systematic review and meta-analysis.

OBJECTIVES: The objective of this systematic review and meta-analysis was to evaluate the effect of chewing gum on orthodontic pain and to determine the rate of bracket breakage associated with fixed orthodontic appliances. METHODS: This review and its reporting were performed according to the Cochrane Handbook for Systematic Reviews of Interventions and the PRISMA guidelines. Six electronic databases were searched up to March 16, 2023, to identify relevant studies that met the inclusion and exclusion criteria. Furthermore, grey literature resources were searched. The Cochrane Collaboration Risk of Bias tool 2 was used to assess the quality of the included studies. Meta-analysis was conducted using RevMan, and sensitivity analysis and publication bias analysis were performed using STATA software. GRADE tool was used to evaluate the certainty of evidence. RESULTS: Fifteen studies with 2116 participants were ultimately included in this review, and 14 studies were included in the meta-analysis. Compared with the blank group, chewing gum had a significant pain relieving effect at all times after fixation of the initial archwire (P ≤ 0.05). No significant difference was found between the chewing gum group and the analgesics group at any timepoints (P > 0.05). Only four studies evaluated the rate of bracket breakage and revealed that chewing gum did not increase the rate of bracket breakage. The sensitivity analysis showed that there was no significant difference in the pooled outcomes after the included studies were removed one at times, and Egger analysis revealed no significant publication bias in included studies (P > 0.05). CONCLUSIONS: Chewing gum is a non-invasive, low-cost and convenient method that has a significant effect on relieving orthodontic pain and has no effect on the rate of bracket breakage. Therefore, chewing gum can be recommended as a suitable substitute for analgesics to reduce orthodontic pain.

Effect of bleaching treatments on the adhesion of orthodontic brackets: a systematic review.

BACKGROUND: Nowadays bleaching procedures have gained popularity in orthodontic patients. Peroxide and Carbamide acids are the common agents which are used in in-office and at home bleaching techniques. Consequently, the Bonding adhesion to the enamel can be influenced by the orthodontic phase and the residual peroxide might interfere with the polymerization and the adhesion of the brackets. Frequent debonding of the brackets from teeth after the bleaching procedure could cause the lengthening of the therapy and promote irregularities on enamel surface derived from an additional bonding phase of the brackets. The aim of this systematic review is to appraise the influence regarding the effect of the bleaching procedure on the bond strength of orthodontic brackets. METHODS: An electronic database search was performed. Search terms included: bleaching, brackets, adhesion; data were extracted and summarized. Risk of bias was assessed using the Chocrane risk of bias tool, adapted for in vitro studies. RESULTS: A total of 8689 articles were screened and 11 studies met the inclusion criteria of this systematic review. 1000 teeth of human and bovine origin were analyzed for the shear bond strength (SBS) of stainless and ceramic brackets after the bleaching treatments. All the authors divided the groups in different subgroups with different bleaching agents and in different concentration. The SBS value allowed to demonstrate the necessity to delay the bonding of the brackets for two weeks after a bleaching treatment and its improvement when tooth mousse or antioxidants agents are used. CONCLUSIONS: The SBS values and the delay of the bonding procedure must be considered in dental practice and clinical strategies are necessary in order to avoid drawbacks which could cause the debonding of the brackets after bleaching due to the alterations of the dental substrate, thus interfering with the orthodontic treatments.

White spot lesions in orthodontics: consensus statements for prevention and management.

OBJECTIVE: To establish consensus recommendations for clinicians to manage white spot lesions (WSLs) during orthodontic treatment. MATERIALS AND METHODS: Three task force members reviewed the literature to identify best practices for minimizing WSLs during orthodontic treatment. Each draft statement was read to the task force members by a facilitator, followed by voting, accepting, or editing if necessary. The statements were then sent electronically by an independent third party (Magellan Medical Technology Consultants Inc, Minneapolis, Minn) to a previously formed content validation panel consisting of 20 independent private practitioners and clinical academicians for validation. RESULTS: Twenty-one statements were developed and sent for content validation. While 19 statements achieved a content validation index (CVI) of 0.78, two items did not. These items were edited by the task force members based on qualitative feedback from content validation participants. Each of these revised statements did achieve a CVI of 0.78 on second evaluation from the content validation panelists and therefore were included in this document. CONCLUSION: To reduce the risk of WSLs, it is essential to implement individualized caries management measures based on a comprehensive assessment of the patient's oral and systemic health. Effective at-home and professional mechanical and chemical plaque control should be implemented for high-risk orthodontic patients. Fluoride to support prevention and materials such as orthodontic sealants should also be used to provide a physical barrier around the brackets in high-risk patients. By following these guidelines, orthodontic professionals can help promote oral health and minimize the need for restorative treatment.

Delayed Severe Gingivitis After Placement of Orthodontic Braces in an Atopic Teenager: A Case Report and Literature Review.

We report a case of a 15-year-old atopic patient presenting with delayed, severe ulcerative hypertrophic gingivitis after placement of orthodontic braces, which required removal of braces and restorative laser surgical procedures. Patch testing to multiple metals and chemicals showed weak positive reactions to steel bands and formaldehyde. The patient experienced urticarial, gingivitis, and other intraoral symptoms after patch testing and re-exposure to nickel-containing products. In contrast, nickel, cobalt, and cobalt-chromium (Co-Cr) bracket patch testing sites were negative. Nickel-caused contact dermatitis is Type IV delayed hypersensitivity reaction occurring at least 24 h after exposure. This reaction can result in intraoral blisters, ulcerations, eczematous and urticarial reactions of the face and more distant skin areas. This case illustrates the intraoral delayed response, symptom resolution after removing the braces, and brackets and local reactions upon subsequent nickel exposure, despite negative patch testing and lymphocyte stimulation test to nickel. This case further illustrates the difficulty associated with diagnosing nickel allergy.

Comparison of three orthodontic bonding systems in white spot lesion development: a randomized clinical trial.

OBJECTIVES: To compare the development of white spot lesions (WSLs) during fixed orthodontic therapy among a conventional three-step bonding system, a self-etching primer bonding system, and a one-step adhesive bonding system. MATERIALS AND METHODS: Seventy-five patients were randomly allocated into three groups (group 1, conventional bonding system, n = 25; group 2, self-etch primer, n = 25; group 3, primer mixed with adhesive composite, n = 25). Quantitative light-induced fluorescence (QLF) was used to assess WSL parameters. Images were captured and then analyzed before treatment and at 2 months and 4 months after bond up. Lesion area (pixels), mean fluorescence loss (ΔF), and the number of newly developed WSLs were compared within and among the three groups. The significance level was P ≤ .05. RESULTS: The mean increase in lesion area was 31.3 ± 2.8 pixels, 38.4 ± 4.3 pixels, and 119.5 ± 5.3 pixels for groups 1, 2, and 3, respectively (P ≤ .001). For ΔF, the loss was 3.3% ± 0.3%, 4.4% ± 0.2%, and 6.6% ± 0.2% for groups 1, 2, and 3, respectively. These changes were significantly different (P ≤ .01 to P ≤ .001). The incidence of newly developed lesions was 9.5 WSLs in group 1, 10 WSLs in group 2, and 15.9 WSLs in group 3. CONCLUSIONS: The lack of primer contributed to the development of a larger number of and more severe WSLs.

Effect of self-assembling peptide and other remineralizing agents on preventing initial enamel lesions around orthodontic brackets: An in vitro comparative study.

OBJECTIVE: To investigate and compare the effect of self-assembling peptide SAP (P11-4), casein phosphopeptide-amorphous calcium phosphate fluoride paste (CPP-ACPF), and fluoride varnish (FV) on preventing enamel demineralization around orthodontic brackets. MATERIAL AND METHODS: Orthodontic brackets were bonded to the buccal surfaces of 80 freshly extracted human maxillary premolars. Teeth were randomly assigned to four groups (n=20) according to the remineralizing agent used as follows: SAP (P11-4) group (Curodont™ Protect/Credentis), CPP-ACPF group (MI Paste Plus®/Recaldent™), fluoride varnish group (Profluoride varnish®/VOCO), and control group. All products were applied according to the manufacturer's instructions. Specimens were cycled in daily refreshed demineralizing and remineralizing solutions for 8h and 16h, respectively, for 28 days. The calcium/phosphorus ratio (Ca/P) and surface microhardness (SMH) were evaluated at baseline and at two and four weeks. Two-way ANOVA (analysis of variance), one-way ANOVA and repeated measures ANOVA were used for statistical analysis. RESULTS: Two-way ANOVA demonstrated significant differences between remineralizing agents and time points. After 4 weeks, the SAP (P11-4) group had had significantly higher Ca/P ratio and SMH (1.68±0.11 and 346.47±55.38) compared to other groups, followed by CPP-ACPF (1.52±0.19 and 283.53±64.75), FV (1.37±0.14 and 262.80±82.98), and the control group (1.31±0.10 and 213.00±41.95). Significantly higher Ca/P ratio and SMH were observed at 2 weeks in the control group (1.44±0.10 and 269.63±57.37) and FV group (1.52±0.09 and 321.17±55.24) compared to 4 weeks. No significant differences were found regarding Ca/P ratio and SMH at 2 weeks in the CPP-ACPF (1.55±0.15 and 295.14±53.88) and SAP P11-4 groups (1.64±0.10 and 320.18±58.04) compared to 4 weeks. CONCLUSION: SAP (P11-4) had the greatest remineralizing efficacy compared to FV and CPP-ACPF. Moreover, extended period of time improved the preventive efficacy of SAP (P11-4) compared to the other regimens.

Self-ligating brackets do not reduce discomfort or pain when compared to conventional orthodontic appliances in Class I patients: a clinical study.

OBJECTIVES: To compare the intensity, location, and short-term impact of the periodontal discomfort/pain, as well as the related functional parameters of bite force and masticatory efficiency, between self-ligating and conventional orthodontic appliances. MATERIALS AND METHODS: In 20 patients referred for orthodontic treatment, samples were collected from the gingival sulcus to evaluate the level of substance P using enzyme-linked immunosorbent assay. Orthodontic devices were randomly bonded, with self-ligating appliances on one side and conventional brackets on the contralateral side. Pain threshold (PT), maximal bite force (MBF), and masticatory efficiency (ME) were assessed using standard validated techniques at the beginning of the treatment and 24 hours post-orthodontic activation with an 0.016-inch nickel-titanium wire. RESULTS: There were no significant differences (P > .05) in the substance P levels, PT, MBF, and ME between the self-ligating and conventional orthodontic appliances. CONCLUSIONS: There was no difference between conventional and self-ligating appliances in the parameters of pain: substance P and pressure. Functional aspects, such as pain, discomfort, and masticatory efficiency, should not be considered when making a therapeutic decision regarding the use of self-ligating vs conventional orthodontic appliances.

Introducing and assessing the efficacy of a novel method to reduce enamel damage after orthodontic bracket removal using two herbal-based resin colouring agents: An in vitro study.

PURPOSE: The differentiation of resin remnants from enamel is a critical factor to minimize enamel damage after bracket debonding. This study was conducted to produce, and ascertain the efficacy of two colouring agents in minimizing enamel loss, adhesive and bonding remnants, and surface roughness after debonding. METHODS: Two dyes containing annatto (orange colour) and curcumin (yellow colour) were produced. Seventy-two maxillary premolars were divided into three groups. After bracket bonding and debonding, the adhesive remnant was removed with a fine diamond bur. In groups 1 and 2, the orange and yellow dyes were utilized during the removal process, respectively. In group 3 (control) adhesive was removed with no colouring agent. The buccolingual dimension of the teeth was measured at the occlusal, middle, and apical areas, before bonding and after clean-up. The adhesive remnant index (ARI) and bonding remnant index (BRI) scores were recorded and the surface roughness parameters were measured. Data were analysed by ANOVA, Tukey, and Fisher's exact tests (α=0.05). RESULTS: Enamel loss was significantly lower in the groups cleaned by the use of colouring agents than that of the control group (P<0.05). No bonding agent was observed when the dyes were used, whereas 65% of teeth in the control group showed the remaining bonding material (P<0.001). There was no significant difference in ARI scores or surface roughness alterations among the study groups (P>0.05). CONCLUSION: The two dyes produced in this study were effective in enhancing the visibility of residual resin materials and minimizing enamel loss during the clean-up process.

Evaluation of Nano TiO2 Modified Orthodontic Composite Effects on S. mutans Population and Enamel Demineralization in Fixed Orthodontic Patients; a Split Mouth Randomized Controlled Clinical Trial.

The high incidence of demineralization around orthodontic brackets has led to the development of preventive measures. Incorporation of antibacterial or remineralizing agents into orthodontic adhesives is an attractive method. This single-center, split-mouth, randomized controlled clinical trial was conducted to assess the effect of a modified composite containing TiO2 nanoparticles on the Streptococcus mutans population and to prevent demineralization around orthodontic brackets. Each participant was assigned a random sequence (AB or BA). During the bonding session, the control lateral incisor was bonded with a conventional composite and the contralateral incisor was bonded with a composite containing nano TiO2 particles (1%weight). The eligibility criteria included the presence of S. mutans in the dental plaque and absence of active caries, fractures or cracks. The S. mutans count in the dental plaque immediately around the brackets was evaluated at baseline and 1, 3, and 6 months after bonding. The specificity of the colonies was determined by PCR. The DIAGNOdent score was assessed at baseline and re-assessed every month up to the sixth month. Salivary samples were collected at T0, T1, and T3 to assess the amount of Ti released from the composite. The cytotoxicity of the modified composites was evaluated using an MTT assay. Participants, examiners, and data analyzers were blinded to the test and intervention groups. Forty-two patients ranging from 12 to 25 years were enrolled in this study. The amount of Ti released into saliva was insignificant and far below the toxic level. There was no significant difference between the S. mutans counts of the studied tooth S. mutans counts at any time point evaluated. DIAGNOdent scores on both sides increased significantly after the first month. However, this increase was higher on the test side (p < 0.001), and a significant difference of 2.6 scores remained throughout the study period. No severe adverse events were observed. Orthodontic composites containing TiO2 nanoparticles may prevent demineralization induced around brackets during orthodontic treatment. However, the antibacterial effects were not statistically significant.Registration: The protocol was registered with the IRCT.ir (IRCT20140215016582N6).

Use of bioluminescence measurements for detection of artificial demineralization adjacent to orthodontic brackets.

PURPOSE: Enamel demineralization can occur as a side effect during orthodontic treatment with fixed appliances and should be detected as early as possible. A new approach to assess demineralization is a system consisting of a photosensitive protein that binds to free calcium ions at the enamel surface. A camera is then used to visualize the bioluminescence spots. This in vitro study aimed to evaluate the ability of the bioluminescence technology to assess artificially demineralized enamel adjacent to various orthodontic brackets. METHODS: In all, 108 human enamel samples were allocated randomly to groups with different orthodontic bracket material: stainless steel, titanium, ceramic. Initial lesions were created adjacent to the brackets. The samples were assessed by bioluminescence before and after demineralization. Images were assessed for presence of bioluminescence spots (yes/no). To quantify the bioluminescence measurements, the images' pixel values (P) were calculated within a defined area (F) adjacent to each bracket before and after demineralization. Quantitative light-induced fluorescence measurements (ΔF, ΔQ) were performed as the reference standard for demineralization. RESULTS: After demineralization, bioluminescence spots were visible (yes/no decision) in 87% of the samples. The pixel analysis of the bioluminescence spots showed significantly higher pixel values after demineralization compared to baseline (p < 0.0001). The bracket material had no influence on the bioluminescence measurements. All samples showed fluorescence loss with a median ΔF of -9.52% (±3.15) and a median ΔQ of -1.01%â€¯× mm2 (±3.34), respectively. CONCLUSION: The bioluminescence technology is a promising tool to demonstrate demineralization adjacent to different orthodontic brackets in vitro.

Effect of calcium fluoride nanoparticles in prevention of demineralization during orthodontic fixed appliance treatment: a randomized clinical trial.

BACKGROUND: White spot lesions (WSLs) are the most common complications of fixed appliance orthodontic treatment. OBJECTIVES: To evaluate the effectiveness of calcium fluoride nanoparticles-containing orthodontic primer (nCaF2-primer) in preventing the incidence of WSLs during orthodontic treatment. TRIAL DESIGN: Single-centre, double-blinded, split-mouth, randomized clinical trial. METHODS: The sample involved 31 orthodontic patients (≥12 years). Participants were recruited using a simple nonstratified randomization. Data collection, measurements, and analysis were performed blindly. Outcome measures included comparing the effect of nCaF2-primer with control primer (Transbond) regarding the degree of demineralization (DIAGNOdent pen), Streptococcus mutans (S. mutans) bacterial counting [real-time polymerase chain reaction device (PCR)], and WSLs incidence (pre- and post-operative photographs). The measurements were performed before bonding, 1, 3, and 6 months after bonding and after appliance removal. A two-way repeated measure analysis of variance test (for DIAGNOdent pen scores), and Wilcoxon signed-rank test (for the difference between bacterial counting and WSLs incidence) were used (P < 0.05). RESULTS: Thirty-one patients were recruited and randomized (mean age 17.9 ± 2.45 years). For the primary outcome (DIAGNOdent pen scores) and secondary outcome of S. mutans counting: 31 patients (310 teeth for each group) were included in scoring at T1 and T3, and 30 patients (300 teeth) were included at T6. While for the photographic scores, 26 patients were included after bracket bonding. The demineralization scores showed significant differences at all-time intervals within the 6 months after bracket bonding which was more noticeable after the first month. There was a significant difference in bacterial count between the two primer groups at the T1 only. Regarding photographic scores, there were no significant differences in the WSLs incidence between the two primers groups after brackets removal. No harm was detected during treatment, except the usual pain/gingival irritation. CONCLUSIONS: nCaF2-primer effectively decreased demineralization scores within the 6 months after bracket bonding. Moreover, it significantly reduced S. mutans colonization after the first month. However, the tested primer did not have an extra advantage in preventing WSLs development at the clinical level after appliance removal. TRIAL REGISTRATION: The trial was registered with ClinicalTrials.gov on 8 May 2021 (registration number: NCT04994314).

Ability of a Blue Hemoglobin-Based Liquid as a Novel Technology to Stain Initial Enamel Demineralization: A Proof-of-Concept in vitro Study.

During orthodontic treatment, enamel demineralization can occur. Its early detection is the basis for efficient preventive measures to arrest or remineralize lesions. In the present study, the application of a novel blue hemoglobin-based liquid (BlueCheck) was evaluated as proof of concept for detection of artificially demineralized smooth surfaces. 60 samples from extracted human posterior teeth were randomly assigned to four groups (15 per group). In 30 of these samples (groups A and B), superficial enamel was removed to create a ground surface. On the surface of other 30 samples (group C and D), orthodontic metal brackets were bonded. On each surface, BC liquid was applied and rinsed with water after 3 min (baseline). All surfaces were checked by two independent observers for presence of blue areas. On each sample, one side was covered by nail varnish to protect this enamel part from demineralization. The samples were demineralized with lactic acid (pH 4.6) for 7 days (group A and C) and 14 days (group B and D), respectively. Mineral loss was determined using quantitative light-induced fluorescence after demineralization. BlueCheck dye was again applied on the samples and evaluated for presence of stained areas. Histological sections were prepared from randomly selected samples and lesion depth was measured. Kruskal-Wallis test was used for group comparison (α = 0.05). After demineralization, median ΔF value for all samples was -8.25% indicating the presence of an initial demineralization. The difference of ΔF values was not statistically significant between samples at 7 or 14 days of demineralization, nor for samples with and without orthodontic brackets (p = 0.13). At baseline, none of the sample surfaces showed discoloration, whereas a distinctive blue color was visible after demineralization in all samples exposed to acid-exposed areas, corresponding to 100% sensitivity. The internal control surfaces (without demineralization) did not show any staining, corresponding to 100% specificity. Histologically measured lesion depths ranged between 200 and 254 µm. In this in vitro study, staining of demineralized enamel surface areas were shown to be reliable. Based on our results, this easily applicable product seems useful to be an adjuvant method to clinical examination to monitor oral health during an orthodontic treatment on tooth surfaces after removal of dental biofilm.

Bioinspired Anti-demineralization Enamel Coating for Orthodontics.

White spot lesions and enamel cracks are the 2 most prominent diseases that occur after orthodontic treatment and are caused by enamel demineralization from accumulated bacterial biofilms and/or enamel damage caused by the removal of residual adhesive after bracket debonding. Inspired by the self-assembled amelogenin nanoribbons in enamel, we developed an enamel coating with a self-assembling antimicrobial peptide, D-GL13K, to simultaneously reduce demineralization and residual adhesive. The self-assembled amphiphilic nanoribbons significantly increased the hydrophobicity of the etched enamel, which reduced the permeability of the coated enamel surfaces as desired. The antimicrobial activity of this coating was evaluated against Streptococcus mutans by colony-forming unit counting and live/dead assays. The anti-demineralization effect was demonstrated by the reduced demineralization depth analyzed by optical coherence tomography and the increased Vickers hardness. The coatings did not reduce the shear bond strength but significantly reduced the adhesive remnant index score. This bioinspired enamel coating may provide a new strategy for preventing white spot lesions and enamel cracks after orthodontic treatment.

Prevalencia de Porphyromonas gingivalis en un grupo de pacientes con aparatología fija de ortodoncia / Prevalence of Porphyromonas gingivalis in a group of patients with fixed orthodontic appliances

Introducción: existen diversos patógenos que pueden afectar no sólo la salud periodontal, sino también la salud general de los pacientes. Objetivo: determinar la Porphyromonas gingivalis (PG) en el primer molar superior derecho de adolescentes, de entre 12 y 18 años, con al menos un mes de tratamiento de ortodoncia con aparatología fija. Material y métodos: se realizó un estudio observacional, descriptivo, transversal de casos en un grupo de 26 adolescentes con tratamiento de ortodoncia, compuesto de brackets metálicos, tubos o bandas, arcos NiTi termoactivos, módulos, cadenas o ligaduras; sin importar sexo, edad, tiempo de tratamiento o maloclusión. Se formaron dos pares de grupos 1 y 2 (15 mujeres y 11 hombres), A y B (13 mujeres y 13 hom- bres) comparando los resultados obtenidos entre los grupos. Resulta- dos: dentro del grupo 1 y 2 la detección molecular de microorganismos arroja que 80% fueron positivas a la PG, 58.33% presenta maloclusión y en promedio 89% de las pacientes son positivas a PG. La detección molecular del grupo A y B indica que 54.54% fueron positivos a PG, mientras que 83.3% presenta maloclusión y en promedio 47% son positivos a PG. Conclusión: la explicación de los eventos moleculares que se desencadenan en la cavidad oral y los sistemas afectados por PG contribuyen a la prevención de complicaciones al tener una mejor comprensión de los fenómenos infecciosos (AU)

Introduction: there are various pathogens that can affect not only periodontal health, but also the general health of patients. Objective: to determine Porphyromonas gingivalis (PG) in the upper right first molar of adolescents, between 12 and 18 years old, with at least one month of orthodontic treatment with fixed appliances. Material and methods: a cross-sectional descriptive observational study of cases was carried out in a group of 26 adolescents with orthodontic treatment, consisting of metal brackets, tubes or bands, thermoactive NiTi archwires, modules, chains or ligatures; regardless of sex, age, treatment time or malocclusion. Two pairs of groups 1 and 2 (15 women and 11 men), A and B (13 women and 13 men) were formed, comparing the results obtained between the groups. Results: within group 1 and 2, the molecular detection of microorganisms shows that 80% were positive for PG, 58.33% presented malocclusion and an average of 89% of patients were positive for PG. The molecular detection of group A and B indicates that 54.54% were positive for PG while 83.3% presented malocclusion and on average 47% were positive for PG. Conclusion: the explanation of the molecular events that are triggered in the oral cavity and the systems affected by PG contribute to the prevention of complications by having a better understanding of the infectious phenomena (AU)

An assessment of mineral concentration of dental enamel neighbouring hypothetical orthodontic brackets using X-ray microtomography.

OBJECTIVES: Differences in the mineral concentration (MC) level of dental enamel may represent a precursor of white spot lesions adjacent to fixed orthodontic brackets. The aim of the current in vitro study was to compare the MC level central, occlusal and cervical to orthodontic attachments. METHODS AND MATERIALS: A total of 16 enamel blocks were obtained from sound human premolar samples extracted for orthodontic reasons. The buccal portion of the dental enamel blocks was divided into central, occlusal, and cervical regions and then imaged and measured to calculate the level of MC using quantitative X-ray microtomography methods (XMT) at each site. RESULTS: There was a substantial variation in the mineral concentration with the lowest level being detected in the cervical region when compared with other regions. The MC of the gingival zone was significantly lower than that of the middle zone (P<0.05) and was insignificantly lower than that of the occlusal zone. CONCLUSION: Within the limitations of the current study, it can be concluded that the cervical region of the permanent enamel had the lowest mineral concentration using XMT. The cervical region may therefore be more vulnerable to the development of white spot lesions (WSLs) adjacent to a fixed orthodontic appliance during orthodontic treatment. CLINICAL SIGNIFICANCE: Using X-ray microtomography lower mineral concentration in the cervical region of the enamel was observed. This may make these areas particularly susceptible to demineralisation during fixed appliance-based orthodontic treatment and may influence the bond strength of fixed orthodontic attachments.

MRI compatibility of orthodontic brackets and wires: systematic review article.

BACKGROUND: Before the magnetic resonance imaging (MRI) examination fixed orthodontic devices, such as brackets and wires, cause challenges not only for the orthodontist but also for the radiologist. Essentially, the MRI-safe scan of the fixed orthodontic tools requires a proper guideline in clinical practice. Therefore, this systematic review aimed to examine all aspects of MRI-safe scan, including artifact, thermal, and debonding effects, to identify any existing gaps in knowledge in this regard and develop an evidence-based protocol. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement was used in this study. The clinical question in "PIO" format was: "Does MRI examination influence the temperature of the orthodontic devices, the size of artifacts, and the debonding force in patients who have fixed orthodontic bracket and/or wire?" The search process was carried out in PubMed, PubMed Central, Scopus, and Google Scholar databases. The search resulted in 1310 articles. After selection according to the eligibility criteria, 18 studies were analyzed by two reviewers. The risk of bias was determined using the Quality In Prognosis Studies tool. RESULTS: Out of the eligible 18 studies, 10 articles examined the heating effect, 6 were about the debonding effect, and 11 measured the size of artifact regarding brackets and wires. Considering the quality assessment, the overall levels of evidence were high and medium. The published studies showed that heating and debonding effects during MRI exposure were not hazardous for patients. As some wires revealed higher temperature changes, it is suggested to remove the wire or insert a spacer between the appliances and the oral mucosa. Based on the material, ceramic and plastic brackets caused no relevant artifact and were MRI-safe. Stainless steel brackets and wires resulted in susceptibility artifacts in the orofacial region and could cause distortion in the frontal lobe, orbits, and pituitary gland. The retainer wires showed no relevant artifact. CONCLUSIONS: In conclusion, the thermal and debonding effects of the fixed orthodontic brackets and wires were irrelevant or resoluble; however, the size of the artifacts was clinically relevant and determined most significantly the feasibility of fixed brackets and wires in MRI examination.