Microbial Colonization on Elastomeric Ligatures during Orthodontic Therapeutics: An Overview

Influence of elastomeric and steel ligatures on periodontal health during fixed appliance orthodontic treatment: a systematic review and meta-analysis

INTRODUCTION

Metallic and elastomeric ligatures are widely used in orthodontics to secure the archwire within the bracket slots, but elastomeric ligatures have traditionally been associated with increased microbial colonization, which could adversely affect periodontal health.

AIM

This systematic review compares the periodontal effects of elastomeric and steel ligatures used for orthodontic fixed appliances.

METHODS

Unrestricted literature search of 7 databases (MEDLINE, Scopus, Web of Science, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Virtual Health Library) up to July 2023 were performed for randomized / non-randomized clinical studies on humans comparing the two ligation methods during fixed-appliance therapy. After duplicate study selection, data extraction, and risk-of-bias assessment with the Risk of Bias (RoB) 2 or the Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) tool, random-effects meta-analyses of Mean Differences (MD) or Standardized Mean Differences (SMD) and their 95% confidence intervals (CIs) were carried out, followed by assessment of certainty of existing evidence with the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

A total of 11 studies (3 randomized / 8 non-randomized) with 354 patients (mean age 14.7 years and 42% male) were included. No statistically significant differences were seen for plaque index (5 studies; SMD = 0.48; 95% CI = -0.03 to 1.00; P = 0.07), gingival index (2 studies; MD = 0.01; 95% CI = -0.14 to 0.16; P = 0.89), probing pocket depth (2 studies; MD = 0; 95% CI = -0.17 to 0.16; P = 0.97), or Streptococcus mutans counts (4 studies; SMD = 0.40; 95% CI=-0.41 to 1.20; P = 0.21). Elastomeric ligatures were associated with moderately increased total bacterial load (3 studies; SMD = 0.43; 95% CI = 0.10 to 0.76; P = 0.03). Confidence in these estimates was low in all instances due to the inclusion of non-randomized studies with high risk of bias.

CONCLUSIONS

Existing low quality evidence indicates that ligature method does not seem to influence the periodontal health during fixed treatment, even if elastomeric ligatures are associated with a moderate increase of bacterial load.

REGISTRATION

PROSPERO (CRD42023444383).

Microbial contamination profile on esthetic elastomeric ligatures through the checkerboard DNA-DNA hybridization technique : A randomized split-mouth study

OBJECTIVE

The aim of this study is to assess the microbial contamination of three different brands of esthetic elastomeric ligatures.

MATERIALS AND METHODS

Different brands of esthetic ligatures (Unistick Pearl [American Orthodontics, Sheboygan, WI, USA], Power Sticks Pearl [Ortho Technology, Tampa, FL, USA], and Ease [Obscure, 3M Unitek, Monrovia, CA, USA]) were randomly assigned to permanent canines of 25 patients (aged 11-18 years) undergoing corrective orthodontic treatment. After 30 days, the ligatures were removed, processed, and the biofilm composition was analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. The microbiological data were analyzed using a nonparametric mixed model.

RESULTS

The ligatures presented intense microbial contamination after 30 days, but no statistically significant differences were observed among the three groups (p > 0.05). The levels of the evaluated individual species and proportions of the microbial complexes showed no statistically significant differences among the ligature groups (p > 0.05).

CONCLUSIONS

Esthetic elastomeric ligatures became multicolonized by several bacterial species after 30 days of exposure to the oral cavity. However, no relevant differences were observed among the biofilm composition formed on the different ligature brands.

Effect of Charcoal, Probiotic, and Chlorhexidine Mouthwashes on Mechanical Properties and Surface Characterization of Ceramic-Coated Nickel-Titanium Orthodontic Arch Wires: A Comparative In-Vitro Study

AIM AND OBJECTIVES

To determine the impact on the mechanical properties and surface features of ceramic-coated nickel-titanium (CC-Ni-Ti) archwires when subjected to charcoal, probiotic, and chlorhexidine mouthwashes in in vitro conditions.

MATERIALS AND METHODS

Eighty samples of 25 mm were cut from the posterior end of preformed maxillary 0.016'' CC-Ni-Ti super elastic archwires (Koden Company, USA) and distributed into four equal groups. Each group of wires was immersed in artificial saliva (Wet Mouth Mouthwash, ICPA Health Products Ltd., India) (control), charcoal mouthwash (Hello activated charcoal extra freshening mouthwash, Hello Products LLC, USA), probiotic mouthwash (Perfora, Probiotic Rinse, India), and 0.2% chlorhexidine gluconate mouthwash (Sensorange, Orange Biotech, Pvt., Ltd., India) (experimental groups) for 90 min at 37 °C. All samples were taken out of their respective solutions and washed with distilled water prior to testing. A three-point bending test was performed on 15 samples from each group using a universal testing device. During the loading and unloading of the archwires, the yield strength (YS), flexural modulus of elasticity (E), and spring back ratio (YS/E) were calculated. The remaining five wires from each group were observed under the scanning electron microscope (SEM) for surface topography evaluation.

RESULTS

The mean differences of loading YS, E, and YS/E between chlorhexidine and charcoal are 302.91 MPa, 4.28 GPa, and 0.0004, whereas unloading values are 172.32 MPa, 4.16 GPa, and 0.0003, respectively, with a statistical significance of <0.001 in terms of YS and E. The mean differences of loading YS, E, and YS/E between charcoal and probiotic are 305.36 MPa, 4.54 GPa, and 0.0005, whereas unloading values are 173.77 MPa, 3.66 GPa, and 0.0003, respectively, with a statistical significance of <0.001 in terms of YS and E. The mean differences of loading YS, E, and YS/E between chlorhexidine and probiotic are 2.45 MPa, 0.26 GPa, and 0.00007, whereas unloading values are 1.44 MPa, 0.49 GPa, and 0.0000533, respectively, with no statistical significance of >0.001 in terms of YS, E, and YS/E. Surface topography alteration was clearly appreciated in the charcoal and probiotic mouthwash groups compared to charcoal mouthwash.

CONCLUSIONS

Loading and unloading of 0.016" ceramic-coated nickel-titanium archwires showed an increase in mechanical properties except for the spring back ratio on exposure to chlorhexidine, probiotic, and charcoal mouthwashes. Chlorhexidine and probiotic mouthwashes had a higher yield strength and flexural modulus of elasticity in comparison with charcoal mouthwash and artificial saliva on 0.016" ceramic-coated nickel-titanium archwires. More corrosive changes were seen on 0.016" ceramic-coated nickel-titanium archwires when immersed in chlorhexidine, followed by probiotic and charcoal mouthwashes.

Fixed Orthodontic Treatment Increases Cariogenicity and Virulence Gene Expression in Dental Biofilm

Background: Dental caries commonly occurs during orthodontic treatment because fixed appliances can impede effective oral hygiene practices. This study investigated the effects of fixed orthodontic treatment on dental biofilm maturity and virulence gene (gtfB, ldh, brpA, spaP, luxS, and gbpB) expression. Methods: Dental biofilms and virulence gene expression were determined in 24 orthodontic patients before and after treatment of ≥6 months. A three-tone disclosing gel was used to stain dental biofilm and assess its maturity by its color change—pink (new dental biofilm), purple (mature dental biofilm), and light blue (cariogenic dental biofilm). Gene expression levels were determined using real-time PCR. Results: After fixed orthodontic appliance insertion, the percentage of new dental biofilm decreased, whereas that of cariogenic dental biofilm significantly increased (p < 0.05). There was no significant difference in the percentage of mature dental biofilm (p > 0.05). Fixed orthodontic appliances increased gtfB, ldh, brpA, and gbpB gene expression above 1.5-fold in dental biofilm. In contrast, there was no change in spaP or luxS gene expression after treatment. Conclusions: Fixed orthodontic appliance insertion induced ecological changes and cariogenic virulence gene expression in dental biofilm.

Salivary pH changes under the effect of stainless steel versus elastomeric ligatures in fixed orthodontic patients: a single-center, randomized controlled clinical trial

BACKGROUND

Fluctuations in pH of saliva during a prolonged treatment course influences the enamel demineralization progress, which is one of the complications of fixed orthodontic treatment. This randomized clinical trial aimed to evaluate and compare the short-term effects of stainless steel (SS) versus elastomeric (EM) ligatures on salivary pH in patients scheduled for fixed orthodontic treatment.

METHODS

Seventy participants were enrolled in the study (54 female, 16 male) aged 19-36 years who met specific inclusion criteria. They were randomly selected and allocated into two equal groups through computer-generated randomization. All patients received fixed orthodontic treatment using conventional orthodontic brackets. Two commonly used archwire ligature methods were used: SS and EMs. An unstimulated (resting) salivary sample was collected before tying of the ligatures at T0 (baseline), 2 weeks, 6 (weeks), and 12 (weeks). Salivary pH was measured using a digital pH meter. The level of significance was set at p value < 0.05.

RESULTS

The salivary pH level was stable between T0 and T1 (6.72 ± 0.14), then significantly and progressively increased from T1 to T2 (6.78 ± 0.13) and from T2 to T3 (6.81 ± 0.14) with (p < 0.05) in the SS group. In the EM group, the salivary pH level was significantly decreased in all follow-up periods; T0 (6.77 ± 0.16), T1 (6.72 ± 0.14), T2 (6.67 ± 0.13) and T3 (6.64 ± 0.13).

CONCLUSION

The EM ligatures showed a significant decrease in salivary pH to an unfavorable level, which increased the risk of enamel demineralization. Therefore, EMs as ligature material is preferably should not be recommended in patients with high caries index or inadequate oral hygiene. Trial registration ANZCTR.org. (ACTRN12618001647224) http://www.anzctr.org.au/ACTRN12618001647224.aspx . Registration Date: 5/10/2018, "Retrospectively registered".

Evaluation and Comparison of the Effect of Elastomeric Chain and Stainless Steel Ligature Wire on Maxillary Orthodontic Miniscrew Failure

Context:

Orthodontic miniscrews are used for the purpose of conservation of anchorage.

Aims:

The aim of the study was to evaluate the orthodontic miniscrew failure between the elastomeric chain-supported retraction and stainless steel (SS) ligature-aided retraction.

Settings and Design:

This was a cross-sectional split mouth randomized controlled trial.

Materials and Methods:

The sample (30) was divided equally among the control group and the experimental group (15 each). Miniscrews were placed between second premolar and the first molar of maxilla. The experimental group was based on the split mouth technique wherein right or left side of the maxillary arch was treated using either an elastomeric power chain (EPC) engaged to the miniscrews directly (Group 1) or an EPC engaged indirectly to miniscrews with the help of SS ligature wire (Group 2). In control group, implants were placed in maxilla without any retraction force. Clinical signs of inflammation was assessed at the following interval; 7^th day, 14^th day, 1^st month, 2^nd month, and at the time of removal of implant.

Statistical Analysis Used:

Kruskal–Wallis ANOVA test was used.

Results:

Mean rank of gingival inflammation was 28.33 at the 1^st-month interval in Group 1 and inflammation remained high in the this group for all time intervals in comparison to Group 2. Group 2 showed highest mean rank of inflammation of 26.10 at 7^th day. In control group, the inflammation remained low at all the time intervals. Moreover, the difference noted was statistically significant.

Conclusions:

The gingival inflammation around the peri-implant tissue with the application of EPC at various interval remained high in comparison to the EPC with SS group. The gingival inflammation in the control group was very less, and it remained less throughout the different time periods.

Comparison of microbial adhesion and biofilm formation on orthodontic wax materials; an in vitro study

Background/purpose

Orthodontic wax materials are available on the dental market and are given by orthodontists due to pain, sores and irritation caused by treatment. The aim of the study was to compare biofilm formation and microbial adhesion at different time points on different protective materials used against orthodontic wounds in vitro.

Materials and methods

Microbial adhesion and biofilm formation were evaluated against Streptococcus mutans ATCC 25175 and Lactobacillus acidophilus ATCC 4356 standard strains on orthodontic wax materials at the 0, 24th, 48th, 72nd, 96th and 120th hour. The Kruskal Wallis test and Bonferroni test were used for statistical evaluations. Statistical significance was set at p < 0.05.

Results

It was observed that S. mutans formed statistically significantly more biofilm on OrthoDots®CLEAR (OrVance) than Ora-Aid (TBM Corporation) at the 48th hour (p < 0.05). Furthermore, L. acidophilus formed statistically significantly more biofilm on OrthoDots®CLEAR (OrVance) than Brace Gard®(Infa-Lab Inc.) at the 72nd, 96th and 120th hours (p < 0.05).

Conclusion

Significant differences were noted among the different orthodontic wax materials and both S. mutans and L. acidophilus created biofilm on all waxes at different time points in vitro. To prevent biofilm formation, these waxes need to be refreshed and should not be used for more than 24 h. According to our study, biofilm production performances of pathogens on Brace Gard®(Infa-Lab Inc.) are minimal and therefore it may be a better option to use in clinics. However, to our knowledge, this is the first study investigating biofilm formation on waxes and more studies are needed in this field.

Application of Nanotechnology in Orthodontic Materials: A State-of-the-Art Review

Nanotechnology refers to the science that manipulates matter at molecular and atomic levels, and studies matter at the nanoscale level to detect and exploit the useful properties that derive from these dimensions; materials with components less than 100 nm in at least one dimension are called nanomaterials. Nanotechnology is applied in many fields, such as medicine (nanomedicine) and dentistry (nano-dentistry). The purpose of these innovations and research in this field is to improve human life and health. This article aims to summarize and describe what the most recent and known innovations of nanotechnology in dentistry are, focusing on and paying particular attention to the branch that is orthodontics, and on the application of new nanomaterials in the realization, for example, of orthodontic elastomeric ligatures, orthodontic power chains, and orthodontic miniscrews. We also address a very important topic in orthodontics, which is how to reduce the friction force.

Knockdown of DANCR reduces osteoclastogenesis and root resorption induced by compression force via Jagged1

LncRNA DANCR has been proven to be involved in osteoblast differentiation. This study aims to investigate the role of DANCR in osteoclast formation and root resorption in periodontal ligament (PDL) cells induced by compression force (CF). Rat orthodontic tooth movement (OTM) model was established. The molecules expressions in the areas of root resorption form OTM model were measured. The number of osteoclasts was measured using Tartrate-resistant acid phosphatase (TRAP) staining. The bone resorption was detected using pit formation assay. We showed that the expression of DANCR and Jagged1 protein was increased in rat OTM model and human periodontal ligament (hPDL) cells treated with CF, and CF increased the production of Jagged1, RANKL, and IL-6 from the hPDL cells. Moreover, DANCR could positively regulate Jagged1 protein expression. Knockdown of DANCR could change the promotion effect of CF on osteoclastogenesis and bone resorption in vitro and in vivo experiments, while overexpression of Jagged1 reversed si-DANCR effect. Taken together, knockdown of DANCR reduced osteoclast formation and root resorption induced by CF via Jagged1.