Fluoride varnish reduces white spot lesions during orthodontic treatment

In vitro surface analysis of the brushing resistance of orthodontic sealants using two different profilometric evaluation methods

The enamel can be protected by applying orthodontic sealants at the bracket base to avoid the development of white spot lesions caused by inadequate oral hygiene. The aim of this study was to investigate the mechanical resistance of five commonly used orthodontic sealants against brushing in comparison to a positive group. Hydroxyapatite discs were bonded with a metal bracket and a piece of arch-wire was ligated in order to simulate a daily clinical situation (n = 48). Samples were divided into 6 groups of respectively 8 specimens. Sealants were applied around the bracket base according to manufacturer's instructions. Following sealants were used: Group 1: Pro Seal (Reliance Orthodontic Products, Itasca, Illinois, USA); 2: Light Bond (Reliance Orthodontic Products, Itasca, Illinois, USA); 3: ClinproXT Varnish (3M ESPE, Seefeld, Germany); 4: ProtectoCaF2 Nano (BonaDent GmbH, Frankfurt am Main, Germany); 5: Fluor Protector and 6: Tetric EvoFlow (both Ivoclar Vivadent AG, Schaan Liechtenstein). Tooth brushing were simulated for 6 weeks and 6 months with an electric toothbrush. The sealant thickness was measured by mechanical (MP) and optical profilometry (OP) at baseline, after 6 weeks and after 6 months of brushing. Statistical analysis was performed according to two mixed linear models and post hoc Tukey-Kramer comparisons. The significance level was set at 5% (α ≤ 0.05). Pro Seal (MP: 9%; OP: 22%) and Light Bond (MP: 19%; OP: 16%) showed the lowest changes in sealant thickness after 6 months of simulated brushing. ClinproXT Varnish and Tetric EvoFlow recorded no statistically significant results (p > 0.05). The fluoride varnishes ProtectoCaF2 Nano and Fluor Protector could not be conclusively evaluated since the thickness of the sealants could not be determined at baseline. The results of both evaluation methods MP and OP are in good agreement. Pro Seal and Light Bond were resistant against tooth brushing and were able to adequately keep the bracket environment sealed even after 6 months. The two different measuring methods, MP and OP, provide a precise impression of the changes in the surface.

Efficacy of sealants and bonding materials during fixed orthodontic treatment to prevent enamel demineralization: a systematic review and meta-analysis

To analyse clinical studies investigating coating agents such as sealants and other bonding materials to prevent the initiation or inhibit the progress of white spot lesions (WSL) during orthodontic treatment with fixed appliances. Electronic databases (Pubmed, CENTRAL, EMBASE) were screened for studies. No language restrictions were applied. Study selection, data extraction and quality assessment were done in duplicate. Primary outcome included assessment of WSL with visual-tactile assessment and/or laser fluorescence measurements. Twenty-four studies with 1117 patients (age: 11–40 years) and 12,809 teeth were included. Overall, 34 different sealants or bonding materials were analysed. Fourteen studies analysed fluoride and 14 studies non-fluoride releasing materials. Meta-analysis for visual tactile assessment revealed that sealants significantly decreased the initiation of WSL compared to untreated control (RR [95%CI] = 0.70 [0.53; 0.93]; very low level of evidence). Materials releasing fluoride did not decrease initiation of WSL compared to those with no fluoride release (RR [95%CI] = 0.84 [0.70; 1.01]; very low level of evidence). For laser fluorescence measurements no meta-analysis could be performed. The use of sealants seems to be effective in preventing the initiation of post-orthodontic WSL. Furthermore, there is no evidence supporting that fluoride-releasing sealants or bonding materials are more effective than those without fluoride release. No gold standard prevention strategy to prevent WSL during treatment with fixed orthodontic appliances has been established yet. However, based on only a limited number of studies the use of sealants seems to be effective in preventing the initiation of post-orthodontic WSL.

Effect of Chlorhexidine Varnish and Fluoride Varnish on White Spot Lesions in Orthodontic Patients- a Systematic Review

Aim:

The aim of this study is to critically review the studies that studied the effect of Chlorhexidine varnish and fluoride varnish on White Spot Lesion (WSL) in patients undergoing orthodontic treatment.

Materials and Methods:

The electronic database PubMed, The Cochrane Library, Medline, Embase, Google Scholar, Web of Knowledge along with a complimentary manual search of all orthodontic journals till the first week of December 2019 was searched. English language study performed on humans, randomized or nonrandomized clinical trials, comparing the effect of fluoride and chlorhexidine varnish on WSL was included in the review. Quality assessment of included studies was performed.

Clinical Significance:

The need for an adjunct oral hygiene aid to reduce the incidence and prevalence of white spot lesions in orthodontic patients is necessary. The use of these varnishes will aid in the same and thus make the adverse effects of fixed orthodontic treatment negligible.

Review of Literature:

Enamel demineralization is a significant risk associated with orthodontic treatment when oral hygiene is poor. Prevention of demineralization during orthodontic treatment is one of the greatest challenges faced by clinicians despite modern advances in caries prevention. The development of White Spot Lesions (WSLs) is attributed to prolonged plaque accumulation around the brackets.

Results:

The search identified a total of 3 studies that were included in this review. One study had Low risk of bias and the remaining 2 studies had moderate overall risk. Results showed that there was a reduction in the incidence of white spot lesions in orthodontic patients after application of chlorhexidine and Fluoride varnish.

Conclusion:

Low level evidence is available to conclude that the use of chlorhexidine varnishes and fluoride varnishes reduces the prevalence of white spot lesions in patients undergoing fixed orthodontic treatment. Due to its limitations, the results of this systematic review should be handled with caution and further well-planned Randomized Clinical Trial (RCT) are needed to provide a discrete conclusion.

Optical analysis of the behavior of sealants under mechanical, thermal and chemical stress

Regarding their resistance five sealants were tested in vitro after experiencing mechanical, thermal and chemical stress. Included for testing were two fluoride varnishes: Fluor Protector [FP] (Ivoclar Vivadent) and Protecto CaF2 Nano One-Step Seal [PN] (BonaDent) and three fluoride-composite filled sealants (with acid etch technique): Clinpro XT Varnish [CP] (3 M Espe), Pro Seal [PS] & Light Bond [LB] (Reliance Orthodontic Products) and a positive control group [CG] Tetric EvoFlow (Ivoclar Vivadent). The sealants were applied on 180 bovine teeth (n = 10/ sealer) in a standardized manner after bracket bonding. Mechanical pressure and its effect by simulating different time points and standardized electric cleaning protocol was tested first. Followed by thermal burden due to varying thermal stress and thirdly change in pH stress imitating chemical exposure were examined separately. A digital microscope and a grid incisal and apical to the brackets (n = 32 fields) was used to standardize the optical analysis. Material loss due to mechanical stress compared to CG (score 0.00) was CP (1.2%), FP (21.5%), LB (22.2%) and PN (81.1%). No significant difference to CG presented PS. Material loss due to thermal stress was CP (0.5%), PS (2%), FP (2.6%), LB (3.1%) and PN (39.9%). Material loss due to chemical stress was FP (1.8%), PS (2.1%), LB (5.5%) and PN (39.6%). No significant difference to CG presented CP. Only PS and CP had optically provable, good resiliance to mechanical, thermal and chemical stress. Significantly poorer outcomes in particular showed PN.

Do bleaching gels affect the stability of the masking and caries-arresting effects of caries infiltration-in vitro

Objectives

The aim of this study was to evaluate the influence of different bleaching gels on the masking and caries-arresting effects of infiltrated and non-infiltrated stained artificial enamel caries lesions.

Materials and methods

Bovine enamel specimens (n = 240) with each two sound areas (SI and SC) and each two lesions (DI and DC) were infiltrated (DI and SI), stained (1:1 red wine-coffee mixture,70 days), and randomly distributed in six groups to be bleached with the following materials: 6%HP (HP-6), 16%CP (CP-16), 35%HP (HP-35), 40%HP (HP-40), and no bleaching (NBl,NBl-NBr). Subsequently, specimens were pH-cycled (28 days, 6 × 60 min demineralization/day) and all groups except NBl-NBr were brushed with toothpaste slurry (1.100 ppm, 2×/day, 10 s). Differences in colorimetric values (ΔL, ΔE) and integrated mineral loss (ΔΔZ) between baseline, infiltration, staining, bleaching, and pH cycling were calculated using photographic and transversal microradiographic images.

Results

At baseline, significant visible color differences between DI and SC were observed (ΔE_baseline = 12.2; p < 0.001; ANCOVA). After infiltration, these differences decreased significantly (ΔE_infiltration = 3.8; p < 0.001). Staining decreased and bleaching increased ΔL values significantly (p ≤ 0.001). No significant difference in ΔΔE was observed between before staining and after bleaching (ΔE_bleaching = 4.3; p = 0.308) and between the bleaching agents (p = 1.000; ANCOVA). pH-cycling did not affect colorimetric values (ΔE_pH-cycling = 4.0; p = 1.000). For DI, no significant change in ΔZ during in vitro period was observed (p ≥ 0.063; paired t test).

Conclusions

Under the conditions chosen, the tested materials could satisfactorily bleach infiltrated and non-infiltrated stained enamel. Furthermore, bleaching did not affect the caries-arresting effect of the infiltration.

Clinical relevance

The present study indicates that bleaching is a viable way to satisfactorily recover the appearance of discolored sound enamel and infiltrated lesions.

The prevalence of approximal caries in patients after fixed orthodontic treatment and in untreated subjects: a retrospective, cross-sectional study on bitewing radiographs

OBJECTIVE

The aim of this retrospective, cross-sectional study was to investigate the prevalence of approximal carious lesions in patients after fixed multibracket therapy and in subjects without orthodontics on bitewing radiographs.

MATERIAL AND METHODS

Bitewing radiographs of 104 orthodontically treated patients with fixed multibracket appliances were compared to those of 111 untreated subjects. The individuals in both groups were between 15 and 16.25 years of age when radiographs were taken. The test group with orthodontics was recruited from the archive of the Department of Orthodontics at the University of Zürich. The untreated control group was selected randomly from 16 communities in the Canton of Zürich. The approximal surfaces of the permanent premolars and molars of all subjects were assessed by two calibrated investigators.

RESULTS

The average number of enamel lesions in the test group after fixed orthodontic treatment was lower than in the control group (0.57 vs. 1.85, p < 0.001). The same was found for dentin lesions (0.06 vs. 0.49, p < 0.001). The distribution of lesions was similar in both groups.

CONCLUSION

Fewer approximal carious lesions were detected in the test group after fixed multibracket appliances than in the age-matched control group without orthodontic treatment.

Methods used for prevention of white spot lesion development during orthodontic treatment with fixed appliances

OBJECTIVES

The aim of this study was to survey methods that Dutch orthodontists use to prevent development or progression of enamel decalcifications during orthodontic treatment.

MATERIALS AND METHODS

A pre-tested questionnaire was sent by post to all orthodontists in the Netherlands with a private practice (n = 189).

RESULTS

The response rate was 81%. At the start of orthodontic treatment a basic practice protocol for prevention of enamel demineralization was used by 93% of the orthodontists. This included oral hygiene instructions (92%) and the advice for additional use of a fluoride mouth rinse (64%). Other preventive measures were rarely prescribed. About 85% of those who prescribed a fluoride mouth rinse advised to rinse once a day, directly after evening tooth brushing.

CONCLUSIONS

The results suggest that the commonly used practice of fluoride mouth rinsing directly after evening tooth brushing by orthodontic patients during fixed appliance treatment ignores actual evidence of preventive advices. This study recommends mouth rinsing at another moment than after evening tooth brushing, thus increasing the frequency of fluoride intakes, which might enhance the effectiveness in preventing WSL development or progression during orthodontic treatment.

White-spot lesions during multibracket appliance treatment: A challenge for clinical excellence

INTRODUCTION

White-spot lesions (WSL) are one of the most undesired side effects of multibracket appliance treatment (MB). The aim of this study was to investigate the incidence and further course of WSL during and after MB.

METHODS

Four hundred patients (168 boys, 232 girls) meeting the inclusion criteria--all maxillary front teeth fully erupted and visible before treatment, no fillings or structural abnormalities, MB duration of at least 1 year, and retention period of at least 1 year--were selected. The patients' average age was 13.7 years (SD, 3.5), and the average MB time was 1.9 years (SD, 3.6). All patients received standardized general prophylactic instructions. A modification of the WSL index was used to evaluate the 4 maxillary front teeth on introral photos before and after treatment, and after retention.

RESULTS

Before treatment, 32.3% of the patients had WSL. After MB, 73.5% of the patients presented WSL. The incidence of WSL during MB was 60.9% of the patients. After treatment, most patients (63.3%) had mild lesions, but the remaining were affected severely with (26.9%) and without (9.9%) cavitations. Only 26% of the patients were free of WSL all the time. After the retention phase, most (57.1%) of the WSL patients after treatment showed improvement, 26% remained unchanged, and 16.7% deteriorated. Male WSL patients tended to show more severe WSL than did the girls. There was a tendency for increased WSL development during the adolescent years compared with the preadolescent and postadolescent age groups.

CONCLUSIONS

With only standardized general prophylactic measures, new WSL developing on the maxillary front teeth during MB remain a frequent undesired side effect, affecting 60.9% of patients and counteracting our efforts for clinical excellence.

Reduction of biofilm on orthodontic brackets with the use of a polytetrafluoroethylene coating

SUMMARY

Treatment with fixed orthodontic appliances can cause enamel demineralization by increased biofilm adhesion. The purpose of the present study was to investigate whether a polytetrafluoroethylene (PTFE) coating reduces biofilm formation on orthodontic brackets. One PTFE-coated bracket and one uncoated stainless steel bracket were bonded symmetrically on the first or second (four maxillary and nine mandibular) primary molars in 13 adolescent patients (five females and eight males, aged 11.2 +/- 2.8 years; four dropouts) for 8 weeks. Quantitative biofilm formation on brackets was analysed with the Rutherford backscattering detection (RBSD) method, a scanning electron microscopy technique. A total of five RBSD micrographs were obtained per bracket with views from the buccal, mesial, distal, cervical, and occlusal aspects. A two-sided paired t-test was used to compare data. A P-value less than 0.05 was considered significant. Total biofilm formation was 4.0 +/- 3.6 per cent of the surface on the PTFE-coated brackets and 22.2 +/- 5.4 per cent on uncoated brackets. Differences between the two groups were statistically significant (P < 0.05). Pairwise comparison of biofilm formation with respect to location (buccal, mesial, distal, cervical, and occlusal) revealed a significantly lower biofilm accumulation on PTFE-coated brackets on all surfaces. The results indicate that PTFE coating of brackets reduces biofilm adhesion to a minimum and might have the potential to reduce iatrogenic side effects, e.g. decalcification during orthodontic treatment with fixed appliances.