The effect of ligation methods on biofilm formation in patients undergoing multi-bracketed fixed orthodontic therapy - A systematic review

Oral Prevalence of Selenomonas noxia Differs among Orthodontic Patients Compared to Non-Orthodontic Controls: A Retrospective Biorepository Analysis

The oral microbial flora may be significantly altered by orthodontic therapy and the use of fixed orthodontic brackets. Most orthodontic research has focused on cariogenic pathogens, while some evidence has demonstrated an increase in many known periodontal pathogens. However, little is known about the prevalence of the Gram-negative periodontal pathogen Selenomonas noxia (SN) among these patients. Using an existing saliva biorepository, n = 208 samples from adult and pediatric orthodontic and non-orthodontic patients were identified and screened for the presence of SN using qPCR and validated primers. In the pediatric study sample (n = 89), 36% tested positive for the presence of SN, with orthodontic patients comprising more SN-positive samples (87.5%) than SN-negative samples (78.9%), p = 0.0271. In the adult study sample (n = 119), SN was found in 28.6%, with orthodontic patients comprising 58.8% of positive samples and only 28.2% of negative samples (p < 0.0001). These data demonstrated that both pediatric and adult orthodontic patients exhibited higher prevalence of SN compared with age-matched non-orthodontic controls. As this microorganism is associated not only with periodontal disease but also long-term health issues such as obesity, more research is needed regarding the factors that increase the prevalence of this microbe.

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).

The effectiveness of water jet flossing and interdental flossing for oral hygiene in orthodontic patients with fixed appliances: a randomized clinical trial

BACKGROUND

Orthodontic treatment presents challenges with plaque accumulation around brackets, archwires, and elastics, leading to retained plaque and gingival inflammation. Conventional toothbrushing may not be enough, requiring additional oral hygiene aids like interproximal brushes, dental flosses, and water flossers. Limited research exists on comparing water flossing and interdental flossing in orthodontic patients. Therefore, this study aims to assess their effectiveness in maintaining oral hygiene during active orthodontic treatment.

METHODS

A single-blind, randomized, parallel clinical study recruited orthodontic patients with full-mouth brackets and archwires. Thirty participants were randomly assigned to either water jet flossing or interdental flossing groups. All participants were instructed to brush twice daily with a provided toothbrush and toothpaste and use the assigned intervention once daily at night. Clinical measures, including the Gingival Bleeding Index (BI), Plaque Index (PI), and Gingival Index (GI), were recorded at baseline and day 14. Descriptive statistics and statistical tests were performed using SPSS software.

RESULTS

The water jet flossing group demonstrated a slightly higher, albeit non-significant, benefit in plaque removal (median difference of 6.79%%, P = 0.279) and bleeding reduction (median difference of 5.21%%, P = 0.172) compared to the interdental flossing group after two weeks. Both groups showed significant reductions in gingival bleeding index and plaque index from baseline to the 2-week follow-up. The interdental flossing group had median mean percentage differences of 16.13%% (plaque index) and 23.57% (gingival bleeding index), while the water jet flossing group had median percentage differences of 21.87% (plaque index) and 32.29% (gingival bleeding index). No significant changes in gingival index grades were observed in either group.

CONCLUSION

Both water jet flossing and interdental flossing were effective in reducing plaque accumulation and gingival bleeding among orthodontic patients. While no significant differences were found between the two methods, water jet flossing showed a potential advantage. Further research is needed to validate its effectiveness, assess long-term impact, and understand its benefits for orthodontic patients.

Effect of chlorhexidine mouthwashes on periodontal parameters and extrinsic tooth staining in orthodontic patients

INTRODUCTION

Periodontal health and biofilm control are primordial to success in orthodontic treatment. This study aimed to evaluate the effect of chlorhexidine (CHX) mouthwashes on periodontal status and extrinsic tooth staining in orthodontic patients.

METHODS

Thirty-three patients of both sexes, aged 11-33 years, under orthodontic treatment with fixed appliances at <16 months, were randomly distributed into 2 groups. In the control group, patients received mechanical hygiene instruction, and in the experimental group, patients also used CHX wash twice a week for 60 days. The effectivity of the protocols was evaluated using the plaque, gingival, gingival bleeding, and discoloration indexes before the hygiene protocol was applied, 15, 30, and 60 days after protocol implementation.

RESULTS

In the experimental group, there was a decrease in the plaque, gingival, and gingival bleeding indexes at the different evaluation periods (P <0.05). In addition, there was a significant difference in the discoloration index at 60 days compared with initial time points after implementing hygiene protocols in the experimental group (P <0.05). In contrast, there were no significant differences in plaque, gingival, gingival bleeding, and discoloration indexes in the control group at any time (P >0.05).

CONCLUSIONS

CHX mouthwash administered 30 days, twice a week, significantly improved the periodontal status with mild brown staining. After this period, expressive extrinsic tooth staining was observed.

Managing oral biofilms to avoid enamel demineralization during fixed orthodontic treatment

Enamel demineralization represents the most prevalent complication arising from fixed orthodontic treatment. Its main etiology is the development of cariogenic biofilms formed around orthodontic appliances. Ordinarily, oral biofilms exist in a dynamic equilibrium with the host's defense mechanisms. However, the equilibrium can be disrupted by environmental changes, such as the introduction of a fixed orthodontic appliance, resulting in a shift in the biofilm's microbial composition from non-pathogenic to pathogenic. This alteration leads to an increased prevalence of cariogenic bacteria, notably mutans streptococci, within the biofilm. This article examines the relationships between oral biofilms and orthodontic appliances, with a particular focus on strategies for effectively managing oral biofilms to mitigate enamel demineralization around orthodontic appliances.

The effect of surface roughening of orthodontic elastomers on hydrophobicity and in vitro adherence of Streptococcus gordonii

OBJECTIVES

Biofilm formation around orthodontic appliances causes gingivitis, enamel decalcification and caries. Bacteria adhere less readily to superhydrophobic surfaces. The aim of this study was to determine whether a superhydrophobic surface could be generated on orthodontic elastomers by surface modification in order to reduce bacterial adhesion.

MATERIALS AND METHODS

Orthodontic elastomers were modified with sandpapers of various grit sizes (80-600 grit). Surface roughness of the modified and unmodified surfaces was assessed qualitatively with scanning electron microscopy and quantitatively with confocal microscopy. Water contact angles were measured with a goniometer to quantify hydrophobicity. Measurements were performed on unextended elastomers (100% original length) and elastomers extended to 150%, and 200% of the original length. Adhesion of Streptococcus gordonii to saliva coated elastomers was measured by counting colony forming units on agar plates.

RESULTS

Abrasion with different sandpapers produced elastomers with surface roughness (Ra) ranging from 2 to 12 μm. Contact angles followed a quadratic trend with a maximum contact angle of 104° at an Ra of 7-9 μm. Average water contact angles, when viewed perpendicular to the direction of extension, decreased from 99° to 90° when the extension was increased from 100% to 200% and increased from 100° to 103° when viewed parallel to the direction of extension. Bacterial adhesion increased as roughness increased and this effect was more pronounced with elastomer extension.

CONCLUSION

The surface roughness of orthodontic elastomers influences both their hydrophobicity and bacterial adhesion. Superhydrophobicity of elastomers could not be achieved with sandpaper abrasion.

Effectiveness of a Combined Toothbrushing Technique on Cariogenic Dental Biofilm in Relation to Stainless Steel and Elastomeric Ligatures in Orthodontic Patients: A Randomized Clinical Trial

Increased dental biofilm commonly occurs during orthodontic treatment. The aim of this study was to evaluate the effect of a combined toothbrushing method on dental biofilm cariogenicity in patients with stainless steel (SSL) and elastomeric (EL) ligatures. At baseline (T1), 70 participants were randomized (1:1 ratio) to the SSL or EL group. Dental biofilm maturity was evaluated using a three-color-disclosing dye. The participants were instructed to brush their teeth using a combined horizontal-Charters-modified Bass technique. Dental biofilm maturity was reassessed at the 4-week follow-up (T2). We found that at T1, new dental biofilm was the highest, followed by mature and cariogenic dental biofilm in the SSL group (p < 0.05). In the EL group, cariogenic dental biofilm was highly observed, followed by mature and new dental biofilm (p < 0.05). After intervention, cariogenic dental biofilm significantly decreased in both groups (p < 0.05). Moreover, a marked decrease in cariogenic dental biofilm was observed in the EL group compared with the SSL group (p < 0.05). However, the change in mature dental biofilm in the groups was similar (p > 0.05). Our results demonstrated that the combined toothbrushing method reduced cariogenic dental biofilm in the SSL and EL groups.

Comparison of the friction forces delivered by different elastomeric patterns and metal ligature on conventional metal brackets with a NiTi arch wire versus a self-ligating system: An in vitro study

OBJECTIVES

The aim of this study was to measure the frictional resistance of different types of ligatures used on conventional and self-ligating brackets.

MATERIALS AND METHODS

Monoblock (conventional) and Portia (self-ligating) brackets were used and the archwire used was nickel-titanium. On conventional brackets the ligatures tested were the Elastomeric type and steel 0.30 tie-wire. The groups were divided according to the ligature types (n=8): (1) conventional elastomeric ligature; (2) relaxed conventional elastomeric ligature; (3) elastomeric ligature in shape-8; (4) double vertical elastomeric ligatures; (5) double-crossed elastomeric ligatures; (6) crossed ligature; (7) steel wire ligature; and (8) self-ligating ligature (self-ligating bracket). A segment of five brackets, each ligature types, was mounted. The archwire, between the bracket and the ligature, was connected on Instron® Universal test machine to simulate the frictional resistance. The maximum frictional resistance was obtained, and the mean values were submitted to the analysis of variance (ANOVA) and the Tukey's post-hoc test (α=0.05).

RESULTS

The elastomeric ligature in shape-8 showed the highest value compared with other groups (P<0.05). Although the crossed elastomeric ligature presented the lowest mean value and it was not statistically different regarding relaxed conventional elastomeric ligature, steel wire ligature and self-ligating (P≥0.05).

CONCLUSIONS

The frictional resistance was influenced by ligature types. Elastomeric Ligature in shape-8 showed the highest frictional force. Crossed Elastomeric Ligature had the lowest frictional force value.