Longitudinal Changes in Microbiology and Clinical Periodontal Variables After Placement of Fixed Orthodontic Appliances

Does orthodontic treatment using clear aligners and fixed appliances affect periodontal status differently?

DESIGN

Systematic review and meta-analysis of clinical trials, and prospective or retrospective cohort. The protocol of the study was registered in advance on PROSPERO.

DATA SOURCES

An electronic search in MEDLINE (PubMed), Web of Science, Scopus, and The Cochrane Library was conducted by two independent authors up to September 2022. Additionally, OpenGrey and www.greylit.org were searched for gray literature, whereas ClinicalTrials.gov was searched for detecting any relevant unpublished data.

STUDY SELECTION

The review question was defined in PICOS format as follows: population (P), patients undergoing orthodontic therapy; intervention (I), orthodontic therapy with clear aligner (CA); comparison (C), orthodontic therapy with fixed appliances (FA); outcome (O), periodontal health status and development of gingival recession; studies (S), randomized clinical trials (RCTs), controlled clinical trials, and retrospective or prospective cohort studies. Cross-sectional studies, case series, case reports, studies without a control group, and studies with less than 2 months follow-up were excluded.

DATA ANALYSIS

Periodontal health status was assessed as a primary outcome and it was measured in terms of pocket probing depth (PPD), gingival index (GI), plaque index (PI) and bleeding on probing (BoP). Gingival recession (GR) was assessed as secondary outcome, and was measured as the development or progression of GR, shown by the apical migration of the gingival margin occurring between pre- and post-orthodontic treatment. Each periodontal index was assessed in three-time points; short-term (2-3 months from baseline), mid-term (6-9 months from baseline), and long-term (12 months or more from baseline). A descriptive analysis of included articles was performed. Pairwise meta-analyses were conducted to compare outcomes assessed in FA and CA groups and were only performed when studies reported similar periodontal indices at similar follow-ups.

RESULTS

12 studies (3 RCTs, 8 prospective cohort studies, 1 retrospective cohort study) were included in the qualitative synthesis, of which, 8 studies were included in the quantitative synthesis (meta-analysis). A total of 612 patients (321 treated with buccal FA and 291 with CA) were assessed. Results from meta-analyses favored CA in regards to PI, demonstrating a significant difference in the mid-term follow-up (number of studies = 4, standardized mean difference [SMD] = -0.99, 95% confidence interval [CI] = -1.94 to -0.03, I2 = 99%, P = 0.04). There was a tendency to report better GI values with CA, specifically in long-term (number of studies = 2, SMD = -0.46 [95% CI, -1.03 to 0.11], I2 = 96%, P = 0.11). However, no statistical significance between the two treatment modalities was shown for any follow-up intervals (P > 0.05). As for PPD, the long-term follow-up showed statistical significance favoring CA (SMD = -0.93 [95% CI, -1.06 to 0.7], P < 0.0001), whereas short- and mid-term follow-ups did not show significant differences between FA and CA. Overall, patients treated with CA showed better values of BoP and less GR when compared to patients treated with FA.

CONCLUSIONS

Available evidence is still not enough to conclude the superiority of clear aligner therapy in terms of periodontal status during orthodontic treatment compared to fixed appliances.

Effects of chlorhexidine use on periodontal health during fixed appliance orthodontic treatment: a systematic review and meta-analysis

BACKGROUND

Proper oral hygiene and absence of periodontal inflammation is pre-requisite for orthodontic treatment. Chlorhexidine (CHX) is an established oral antiseptic used in the treatment of periodontal disease, but its role in orthodontic therapy is unclear.

OBJECTIVES

To assess the efficacy of adjunct use of CHX-containing products in maintaining gingival health among orthodontic patients with fixed appliances.

SEARCH METHODS

Five databases were searched without limitations up to August 2021.

SELECTION CRITERIA

Randomized clinical trials (RCTs) assessing Gingival Index (GI) (primary outcome), Plaque Index (PI), Bleeding Index (BI), or Pocket Probing Depth (PPD).

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, and risk of bias assessment were done independently in duplicate. Random-effects meta-analyses of mean differences (MDs) or standardized mean differences (SMDs) with their 95% confidence intervals (CIs) were conducted, followed by sensitivity and Grades of Recommendations, Assessment, Development and Evaluation analysis.

RESULTS

Twenty RCTs (1001 patients) were included assessing CHX-containing mouthwashes (n = 11), toothpastes (n = 2), gels (n = 3), or varnishes (n = 4) compared to placebo/control (n = 19) or sodium fluoride-products (n = 4). In the short-term, CHX-containing mouthwash was associated with lower GI (n = 9; MD = -0.68; 95% CI = -0.97 to -0.38; P < 0.001; high quality), lower PI (n = 9; MD = -0.65; 95% CI = -0.86 to -0.43; P < 0.001; high quality), lower BI (n = 2; SMD = -1.61; 95% CI = -2.99 to -0.22; P = 0.02; low quality), and lower PPD (n = 2; MD = -0.60 mm; 95% CI = -1.06 to -0.14 mm; P = 0.01; low quality). No considerable benefits were found from the use of CHX-gel or CHX-varnish in terms of GI, PI, or PPD (P > 0.05/low quality in all instances). Use of a CHX-containing toothpaste was more effective in lowering PI (Heintze-index) than adjunct use of fluoride-containing mouthwash (n = 2; MD = -5.24; 95% CI = -10.46 to -0.02; P = 0.04), but not GI (P = 0.68) or BI (P = 0.27), while sensitivity analyses indicated robustness.

CONCLUSIONS

Adjunct use of CHX mouthwash during fixed-appliance treatment is associated with improved gingival inflammation, plaque control, and pocket depths, but caution is warranted and recommendations about CHX use during orthodontic treatment of children/adults should consider the heterogeneous patient response, cost-effectiveness, and potential adverse effects.

REGISTRATION

PROSPERO registration (CRD42021228759).

Use of an antiseptic rinse (NanArgol) for the oral hygiene maintenance of subjects with fixed appliances: A randomized clinical trial

BACKGROUND

The risk of periodontal diseases development increased in patients with malocclusion undergoing orthodontic treatment. Thus, the aim of this study was to examine the efficacy of the use of adjunctive rinses with nano-Argentum to standard oral hygiene regimen in subjects wearing fixed orthodontic appliances.

MATERIALS AND METHODS

Eighty patients were observed for 1 year. They were divided in two groups: in test group patients were instructed to rinse with non-ionic colloidal silver solution according to protocol for 6 months as an adjunct to standard; in control group the patients followed the standard oral hygiene regimen. Index of efficiency of oral hygiene (PHPm), community periodontal index (CPI) and papillary-marginal-alveolar index (PMA) were evaluated before treatment and after 1 and 6 months. For statistics analysis, Mann-Whitney, Kruskal-Wallis tests and Pearson criterion were used.

RESULTS

Baseline hygiene levels in two groups had no differences. Oral hygiene indices were significantly lower in the test group in comparison with control after 1 month (PHPm = 0.38 ± 0.18 and 1.19 ± 0.45, respectively, p < 0.01; PMA = 11.78 ± 8.5 and 47.25 ± 20.9, respectively, p < 0.05; CPI = 0.65 ± 0.53 and 1.53 ± 0.77, respectively, p < 0.01) and 6 months (PHPm = 0.5 ± 0.2 and 1.2 ± 0.4, respectively, p < 0.01; PMA = 11.62 ± 19.6 and 66.33 ± 27.9, respectively, p < 0.01; CPI = 0.63 ± 0.73 and 1.68 ± 0.78, respectively, p < 0.01).

CONCLUSIONS

The use of the test solution as an adjunct to standard oral hygiene provided a significant beneficial effect in terms of oral hygiene in patients undergoing orthodontic treatment.

Caries-preventive effectiveness of two different fluoride varnishes: A randomised clinical trial in patients with multi-bracketed fixed orthodontic appliances

BACKGROUND

Patients with multi-bracketed fixed orthodontic appliances are at a higher risk of developing enamel demineralisation.

AIM

To compare the efficacy of the quarterly application of two varnishes in preventing white spot lesions (WSLs) during multi-bracketed fixed orthodontic treatment.

DESIGN

Ninety-nine patients were randomly allocated into three intervention groups: Group A-standard oral hygiene instructions (OHI); Group B-5% sodium fluoride (NaF) varnish with standard OHI; and Group C-NaF plus tricalcium phosphate varnish with standard OHI. The outcome was assessed at 6-monthly intervals using a quantitative laser fluorescence device, clinical evaluation and photographic evaluation on six maxillary anterior teeth. A logistic regression model using generalised estimating equations with the intervention group, time and their interaction was used to compare the occurrence of WSLs, whereas the independent-samples Kruskal-Wallis test was used to compare the means of fluorescent values among different groups at p = .05.

RESULTS

Generalised estimating equations (with intervention and time as predictors) showed that only the effect of time was found to be significant (p < .001), whereas there was no significant difference among the three intervention groups (p = .305) using clinical assessment or photographic assessment (p = .599). At the 18-month follow-up, sodium fluoride (NaF) varnish with standard OHI was shown to reduce the odds of WSLs by 55% (p = .200), and NaF plus tricalcium phosphate varnish with standard OHI by 42% (p = .327).

CONCLUSION

The study failed to demonstrate that the quarterly application of both the study varnishes with OHI provided additional benefits compared with standard OHI alone in preventing WSLs, taking the effect of time of follow-up into consideration. There were higher odds of developing WSLs with an increased duration of orthodontic treatment.

CD301b+ Macrophages as Potential Target to Improve Orthodontic Treatment under Mild Inflammation

Due to improvements of quality of life and the demand for aesthetics, more and more people are choosing orthodontic treatments, resulting in a surge in adult orthodontic patients in recent years. However, a large amount of clinical evidence shows that many orthodontic patients have mild periodontitis in the periodontal tissues, which affects the efficacy of the orthodontic treatment or aggravates the periodontal condition. Therefore, it is important to identify the key factors that affect orthodontic treatments in this inflammatory environment. The aim of this study was to investigate the role of macrophages in orthodontic treatments under inflammatory environments. By analyzing the functional groups of macrophages in the orthodontic rat model of periodontitis, we found that macrophages with high expression levels of CD301b could improve the periodontal microenvironment and improve the efficiency of the orthodontic tooth movement. CD301b+ macrophages transplanted into the model can promote osteogenesis around orthodontic moving teeth, improve bone remodeling during orthodontic treatment, and accelerate orthodontic tooth movement. Considered together, these results suggest that CD301b+ macrophages may play an active role in orthodontic treatments in inflammatory environments and may serve as potential regulatory targets.

Immune System Acts on Orthodontic Tooth Movement: Cellular and Molecular Mechanisms

Orthodontic tooth movement (OTM) is a tissue remodeling process based on orthodontic force loading. Compressed periodontal tissues have a complicated aseptic inflammatory cascade, which are considered the initial factor of alveolar bone remodeling. Since skeletal and immune systems shared a wide variety of molecules, osteoimmunology has been generally accepted as an interdisciplinary field to investigate their interactions. Unsurprisingly, OTM is considered a good mirror of osteoimmunology since it involves immune reaction and bone remolding. In fact, besides bone remodeling, OTM involves cementum resorption, soft tissue remodeling, orthodontic pain, and relapse, all correlated with immune cells and/or immunologically active substance. The aim of this paper is to review the interaction of immune system with orthodontic tooth movement, which helps gain insights into mechanisms of OTM and search novel method to short treatment period and control complications.

A survey regarding orthodontic treatment among contemporary college freshmen in China

Background

A growing number of Chinese residents are seeking orthodontic treatment. The aim of the study was to investigate rates of orthodontic publicity, orthodontic treatment history and related factors among college freshmen in China, to preliminarily understand the current situation of orthodontic publicity and treatment in China, especially after the 2020s.

Methods

Referred to previous studies, a self-designed online questionnaire of Chinese college freshmen was conducted. The questionnaire was divided into two parts, after collecting basic information, we investigated orthodontic publicity rate and orthodontic treatment history with starting age, relapse phenomenon, satisfaction score and willingness to re-treatment. Factors hindering first-time and second-time treatment were also collected. The statistical analysis was performed using the Chi-square test, t-test, Kruskal–Wallis test and logistic regression analysis.

Results

The response rate was 100% and 3308 responses were included. The male to female ratio was 1524:1784 with a mean age of 18.43 years (SD 0.91 years). Statistically significant of economic administrative regions, age, major and orthodontics engagement of relatives or friends were found on prevalence and rate of orthodontic treatment (P < 0.05). Average opinion on orthodontic treatment was “satisfied” and most claimed a phenomenon of relapse (slight relapse: 38.22%, obvious relapse: 23.12%), where age, major and orthodontics engagement of relatives or friends showed statistically significant. Retreatment willingness was correlation with start age and relapse phenomenon. For those who refused first-time treatment, except for good tooth arrangement condition, pain, long-time span, and cost weighted, while for those who refused re-treatment, the fair of discomfort and long-time span ranked at the top.

Conclusions

In contemporary China, the prevalence and rate of orthodontic treatment had been greatly promoted. Earlier age for receiving orthodontic treatment was also discovered. Subjective factors regarding psychology, self-requirement affected the need of orthodontic treatment. Contemporary Chinese college freshmen had a high ability of judging dental alignment, while improve of overall orthodontic care level is still required.

Knowledge, attitudes and professional practices of ortho-periodontal care of adults: a cross-sectional survey in France

BACKGROUND

Due to increasing numbers of adult patients, orthodontists are being confronted more and more with periodontal problems. Coordination amongst orthodontists, periodontists and general dentists is useful in preventing and stopping periodontal disease. The main objectives of this survey were to evaluate the technical knowledge, techniques and attitudes employed by French orthodontists, periodontists and general dentists in adult dental care.

METHODS

A cross-sectional online survey was distributed to French dentists. The questionnaire, consisting of 30 questions, was divided into six sections covering treatment programs and the forensic environment.

RESULTS

One thousand one hundred twenty-two complete answers were recorded. Adults undergoing orthodontic treatment represented 19.9% of the orthodontists' patients, but only 2.67% of the general dentists' patients. Communication between clinicians was rated as good, greater than 3 out of 5. Before treatment, orthodontists were less alarmed than generalists regarding bleeding, recessions, increased probing depths, halitosis and hyperplasia. During treatment, orthodontists never or only occasionally performed palpation or probing in 54.2% and 84.6% of cases. Gingivitis and recessions were the main reasons for consultations for 22.0% and 20.1% of general dentists and periodontists after orthodontic treatment. Of the practitioners surveyed, 43% felt that they experienced a setback in the ortho-periodontal treatment.

CONCLUSIONS

This study revealed discrepancies in the knowledge and attitudes of practitioners. Therapeutic management remains one of the major challenges of multidisciplinary treatments. Continuing education needs to be further developed in this field.

Short- term effect of probiotic Lactobacillus reuteri consumption on the salivary microbiome profile of subjects undergoing orthodontic treatment with fixed appliances

Objective

Methods

Results

Conclusion

The Effect of Extrinsic Factors on the Mechanical Behavior and Structure of Elastic Dental Ligatures and Chains

Force provided by elastomers used in orthodontics can be affected by several factors present in the oral cavity. The aim of our study was to investigate the role of mouthwashes, toothbrushing, and smoking in the force decay of such elastomers. Tensile strength, changes in the force continuously exerted, and force decay of elastic chains (Ortho Organizer and Masel Short Power Chain) and elastic ligatures (Dentaurum and Masel) by two separate manufacturers were measured. Measurements were initially made on untreated elastics, followed by exposure to different environmental factors including cigarette smoke, toothbrushing (mechanical plaque control), and two different mouthwashes (chemical plaque control). Changes on the surface of the elastics were studied with scanning electron microscopy (SEM). Untreated Masel elastic ligature showed lower tensile strength than Dentaurum elastic ligature (2339 cN vs. 3660 cN), while significantly higher tensile strength was measured for Ortho Organizer elastic chains than Masel chains (2639 cN vs. 1324 cN). The decrease in the elastic force of Masel ligature was greater in response to all external factors compared to Dentaurum. Although brushing with toothpaste and toothbrush impacted the force of both Masel and Ortho organizer ligatures negatively, force degradation was more apparent in the case of the Ortho organizer. Surface changes were more visible when applying Curasept mouthrinse, however force decay was higher in the Corsodyl group. Mechanical and chemical plaque control can influence the tensile strength and force decay of orthodontic elastomers, which should be considered by selecting the elastomers or determining their changing interval for the practice.

Duration of toothbrushing with fixed appliances: a randomized crossover clinical trial

OBJECTIVE

Fixed orthodontic appliances might result in dental adverse effects, if sufficient oral hygiene is not maintained. Since recommendations on toothbrushing times are lacking scientific justification in orthodontic populations, the aim of the present study was to comparatively quantify the duration of toothbrushing with a manual and a powered toothbrush in two distinct age groups.

TRIAL DESIGN

Two-centre, two-period crossover balanced randomized clinical trial with computer-generated numbers and blinding at the outcome-assessing level.

METHODS

Children and adults with fixed appliances with at least 22 aligned teeth were recruited at a university clinic and private practice in Bavaria, Germany. Plaque was disclosed with staining tablets and participants brushed their teeth with their habitual technique in front of a mirror and without interference until staining was, to their own satisfaction, completely removed. The primary outcome was duration of toothbrushing in seconds. Secondary outcomes were percentage plaque reduction and questionnaire data on dental attitudes and behaviours. Data were analysed with linear mixed models.

RESULTS

Twenty-eight participants were randomized to the first and 27 to the second toothbrush sequence. The combined effect of age and toothbrush on the duration of toothbrushing was evident (n = 52, F(1, 50.8) = 5.1, P = 0.028). Children brushed 14.5 seconds less [n = 28, 95% confidence interval (CI) = -31.3 to 2.3, P = 0.090], yet adults 13.3 seconds more (n = 24, 95% CI = -4.6 to 31.3, P = 0.143) with the manual than powered toothbrush. Brushing times ranged from 2 minutes and 45 seconds to 3 minutes and 17 seconds with plaque reduction at 76% and good dental attitudes and behaviours.

CONCLUSIONS

Both children and adults with fixed appliances might equally reach an effective plaque reduction with either manual or powered toothbrushes and their habitual brushing technique in around three minutes, if plaque is visible.

REGISTRATION

DRKS-German Clinical Trials Register ID: DRKS00012463.

FUNDING

Oral-B Procter & Gamble.

Salivary microbial changes during the first 6 months of orthodontic treatment

Background

Orthodontic treatment is widely used to treat malocclusion. However, the influence of treatment on the oral microbiome remains unclear. In this study, we investigated salivary microbial changes in patients undergoing orthodontic treatment.

Methods

In total, 19 orthodontic patients participated in this study. Saliva samples were collected at the following three timepoints: before (T0) and 3 months (T1) and 6 months (T2) after the placement of orthodontic appliances. High-throughput sequencing was performed based on the 16S rRNA gene V4 region.

Results

The phyla of Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria and Fusobacteria were predominant. Observed Species, Chao1 and ACE, which represent α diversity, were significantly decreased at T1 and subsequently increased at T2. In addition, the β diversity at T1 based on the Bray-Curtis distances differed from T0 and T2. The relative abundances of Prevotella, Porphyromonas and Peptostreptococcus were decreased with treatment, whereas those of Capnocytophaga and Neisseria exhibited the opposite results. In total, 385 of 410 operational taxonomic units were shared at T0, T1 and T2. The co-occurrence networks with hub nodes at T1 were the most complex.

Conclusion

Orthodontic treatment temporarily affected the saliva microbial community. This dynamic alteration in species did not induce deterioration in oral health. Oral hygiene instructions were necessary and should be emphasized during each visit. Further studies with longer observation periods and more participants are required.

The impact of COVID-19 pandemic on patients receiving orthodontic treatment: An online questionnaire cross-sectional study

Background

The spread of Coronavirus Disease 2019 (COVID-19) has led to a major public health issue; most dental clinics were closed and millions of orthodontic patients were unable to complete their treatment. This study aimed to assess the challenges faced by patients receiving orthodontic treatment and their preferred solutions to overcoming these challenges during this pandemic.

Methods

An online questionnaire was developed and sent to patients receiving orthodontic treatment at a public or private clinic.

Results

A total of 388 responses were analyzed: mean age 20.4 ± 4 years, 75% (291) female, and 58% (226) received their treatment at a public clinic. Of all participants, 27.3% (106) were still unable to attend their appointments and 69% (244) stated that closing of the clinic was the main reason for missing their appointments. Depending on their type of appliance, the patients faced different problems and chose multiple ways to deal with them. Most participants had fixed appliances, 84% (327), and only 21% (64) of them stated that they had no problem compared with 39% (11) and 36% (8) for removable appliance and clear aligner groups, respectively.

Conclusion

The COVID-19 pandemic has had a significant impact on orthodontic treatments. Almost every orthodontic patient had to stop attending their appointments, which put them in complicated situations and in fear of delayed treatment. Patients from a public clinic and patients with fixed appliances reported more problems than others. More attention should be giving to teleorthodontics; also orthodontists should prepare their patients to deal with some of the problems related to their appliances when possible.

Periodontal parameters in adult patients with clear aligners orthodontics treatment versus three other types of brackets: A cross-sectional study

OBJECTIVE:

To assess the gingival parameters in the clear aligner treatment versus the three other types of brackets, i.e., conventional metal, conventional ceramic, and metal self-ligating.

MATERIALS AND METHODS:

Eighty patients coming for regular appointments undergoing orthodontic treatment were included. They were further divided into four groups with 20 patients in each: Group one underwent conventional brackets (CB) treatment; Group two had conventional ceramic brackets (CCB); Group three was treated with self-ligating (SL) brackets; Group four underwent with clear aligner (CA) treatment. Inclusion criteria were any patient with a minimum age of 18 years having Class II, Class III skeletal relationship, undergoing orthodontic treatment for at least 6 months with fixed orthodontic appliances (FOA) on both arches. While smokers, pregnant, diabetics, or those taking medication affecting gingival health or having cardiovascular diseases were excluded. Also excluded were patients who used antiseptic solutions or mouthwash during the past 6 months, underwent any periodontal treatments in the past 6 months, or who had fixed bridges and crowns or extensive restorations close to the gingival margins. Seven indices, namely plaque index, gingival index, gingival bleeding index, sulcus bleeding index, papillary bleeding index, basic periodontal examination index, and bleeding on probing index, were recorded for all groups.

RESULTS:

Mean age for Group 1 with CB was 26.65 ± 5.15 years, whereas it was 27.65 ± 8.15 years for Group 2 with CCB, and 26.85 ± 5.19 for Group 3 with SB. Group-4 with CA treatment had a mean age of 26.85 ± 4.83 years. Multivariate analysis and a Bonferroni correction was performed (P = 0.008). CA treatment has better periodontal parameter values compared with the CB and the CCB groups, and no significance difference with the SL brackets group.

CONCLUSION:

CA treatment has better periodontal indices levels compared to other types of orthodontic treatments such as CB and the CCB groups; no significant difference with the SL brackets group. Importance should be given to oral hygiene instructions before, during, and after the treatment.

Clinical, microbiological, and immunological evaluation of patients in corrective orthodontic treatment

Background

The objective was to analyze clinical, microbiological, and immunological periodontal parameters in patients in corrective orthodontic treatment.

Materials and methods

Twenty-eight patients were selected. Plaque index (PI), bleeding on probing (BOP), width of keratinized gingiva, levels of 40 bacterial species, and of 3 cytokines (IL-1β, MMP-8, and TNF-α) in gingival crevicular fluid (GCF) were evaluated at T0, before orthodontic treatment; T1, 6 months; and T2, 12 months post-treatment. Non-parametric, Friedman, Wilcoxon, ANOVA, and Spearman correlation coefficient tests were used for statistical analyses, with the significance level of 5%.

Results

No significant difference was found for the width of keratinized gingiva, but PI presented a significant increase at T1 and T2 (p < 0.05) when compared with T0. The percentage of sites with BOP increased significantly from T0 to T1 (p < 0.05); however, at T2, the values decreased and did not differ anymore from T0 (p > 0.05). In the microbiological analysis, red complex pathogens were in significantly greater proportions in T2 compared with T0 (p < 0.05). There was no statistically significant difference in the cytokine levels between the periods but there was a positive correlation between BOP and IL-1β (r = 0.49 p = .01) and TNF-α (r = 0.39 and p = .05).

Conclusion

In conclusion, corrective orthodontic treatment caused clinical periodontal alterations regarding biofilm accumulation and gingival bleeding, with alteration of periodontopathogens.

Microbial profile in different orthodontic appliances by checkerboard DNA-DNA hybridization: An in-vivo study

INTRODUCTION

The design of the orthodontic bracket or appliance is 1 of the most important factors for creating retentive areas for biofilm formation. In orthodontics, this would be the first study to compare the microbial level changes in 3 different types of orthodontic appliances using checkerboard DNA-DNA hybridization technique. The purpose of this study was to evaluate and compare the extent of appearance of orange and red microbial complexes in patients undergoing orthodontic treatment using aligners, conventional metallic fixed labial appliances, and lingual fixed appliances.

METHODS

A total of 60 patients, of which 20 patients were undergoing treatment with aligners, 20 patients with labial fixed appliances, and 20 patients with lingual fixed appliances, were included in our study. After 30 days, debonded brackets and rinsed aligners were stored and processed for analysis with checkerboard DNA-DNA hybridization.

RESULTS

Most bacterial species showed moderate counts, with the exception of Treponema denticola, which showed a higher count in all 3 types of appliances. Fusobacterium nucleatum, Porphyromonas gingivalis, and T denticola were present in a higher percentage in the lingual appliance. Fusobacterium periodontium and Prevotella intermedia were present in a higher percentage in the labial fixed appliance. Campylobacter rectus, Tannerella forsythia, and Prevotella melaninogenica counts were moderate in all 3 appliances, with the first 2 microbes showing slightly higher counts in aligners. The association between all the microorganisms were statistically insignificant, with the exception of F nucleatum, which showed a strong statistically significant association in all 3 types of appliances.

CONCLUSIONS

The microbial contamination in metallic brackets was higher than that of aligners, when used for a month. Lingual fixed appliances showed more microbial contamination than labial fixed appliances followed by aligners.

Quantitative analysis of biofilm formation on labial and lingual bracket surfaces

OBJECTIVES

To evaluate and compare the biofilm formation between labial and lingual orthodontic brackets.

MATERIALS AND METHODS

Twenty patients with a mean age of 24 ± 8.8 who had received labial or lingual orthodontic treatment were enrolled in the study. Biofilm formation on 80 brackets was analyzed quantitatively with the Rutherford backscattering detection method. Five micrographs were obtained per bracket with views from the vestibule/lingual, mesial, distal, gingival, and occlusal aspects. Quantitative analysis was carried out with surface analysis software (ImageJ 1.48). Data were analyzed by Mann-Whitney U and Kruskal-Wallis tests (α = 0.05).

RESULTS

Total biofilm formation was 41.56% (min 29.43% to max 48.76%) on lingual brackets and 26.52% (min 21.61% to max 32.71%) on labial brackets. Differences between the two groups were found to be significant. No difference was observed in intraoral location. The biofilm accumulation was mostly located on gingival, mesial, and distal surfaces for both groups.

CONCLUSIONS

The biofilm accumulation on lingual orthodontic therapy was found to be more than labial orthodontic therapy.

Efficacy of a Copper-Calcium-Hydroxide Solution in Reducing Microbial Plaque on Orthodontic Clear Aligners: A Case Report

The aim of this study was to investigate the ability of a copper–calcium–hydroxide-based compound to remove microbial plaque naturally produced onto orthodontic clear aligners. A commercially available dental paste, named Cupral, based on copper–calcium–hydroxide, was used. A healthy volunteer (female, 32 years old), undergoing orthodontic treatment with thermoplastic clear aligners was enrolled. By conventional/confocal microscopy and colony-forming unit (CFU) assay, 2-week used aligners were examined for microbial plaque, prior and following exposure to Cupral. Confocal microscopy revealed abundant plaque irregularly distributed onto the aligner surface. Following Cupral treatment, a drastic decrease occurred in plaque thickness and matrix presence. As assessed by the CFU assay, total microbial load approached 10 ⁹ CFUs/aligner, with slight differences in aerobiosis and anaerobiosis culture conditions; six macroscopically different types of colonies were detected and identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Following Cupral treatment, microbial load dropped to undetectable levels, irrespectively of the conditions considered. Exposure of clear aligners to Cupral results in the elimination of contaminating microorganisms; the antimicrobial activity is retained up to 1.25% concentration. Overall, our data describe a novel use of Cupral, a copper–calcium–hydroxide-based compound, in daily hygiene practices with promising results.

Orthodontic treatment as an adjunct to periodontal therapy

This study discusses the role of orthodontic treatment as an adjunct to the control and treatment of periodontal disease conditions, and describes a clinical case of severe anterior mandibular crowding and periodontal disease followed up for nine years and three months after orthodontic treatment completion. Malocclusion impaired proper dental hygiene, which led to bone loss and development of a periodontal abscess between mandibular canines and lateral incisors. After scaling and root planing, orthodontic treatment was initiated with extraction of the four second premolars, to correct the deficiency detected in cephalometric and model analysis. Treatment objectives were met, and facial and dental esthetics was satisfactory. Adequate periodontal management, hygiene control and tooth movement ensured ideal occlusion and facilitated the control of biofilm.

The Microflora Diversity and Profiles in Dental Plaque Biofilms on Brackets and Tooth Surfaces of Orthodontic Patients

Objective: Fixed orthodontic appliances may influence the oral environment through accumulation of plaque, decreased plaque pH, and increased gingival inflammation. These changes in the oral cavity can potentially lead to periodontal disease, demineralization, and other infectious diseases.

Materials and Methods: To investigate the changes in biofilm throughout the initial 2 weeks, we placed a stainless steel bracket on the upper second premolar and collected plaque samples on the bracket and on the tooth surface at different time points (0, 24, 48 h and 1 and 2 weeks) and plated on tryptic soy agar blood agar plate, and kept at 37°C in an anaerobic chamber for 5 days to determine the CFUs of bacteria. At the end of 2 weeks, we removed the bracket and elastomeric module, and we isolated genomic DNA from the bacterial biofilm for identification of bacteria by 16S rRNA PCR analysis. We also analyzed the morphology of biofilm on the bracket by scanning electron microscope.

Results: Our results show that the bacterial biofilm was significantly increased on the bracket in all the subjects, whereas on the tooth surface, the CFUs were not significantly increased. PCR assay showed that biofilm on orthodontic brackets from all subjects showed colonization by Streptococcus gordonii, Porphyromonas gingivalis and Streptococcus mutans were observed on some of the subjects after 48 h, whereas Aggregatibacter actinomycetemcomitans biofilm was observed in all the time points except 24 h.

Conclusion: This study demonstrated that both periodontal and cariogenic bacterial biofilms were formed on the bracket as early as 24 h.

Correlation between the DAI and ICON Indices used for Assessment of Orthodontic Treatment need in Croatian Schoolchildren

INTRODUCTION

The aims were: evaluation of the correlation between the Dental Aesthetic Index (DAI) and Index of Complexity, Outcome and Need (ICON); the assessment of orthodontic treatment need for schoolchildren in a population with two indices, separately for schoolchildren with mixed and permanent dentition; the estimation of the population share that could not receive orthodontic treatment because of the presence of caries and/or gingivitis.

METHODS

A total of 2652 Zagreb school children (7 - 19 years old, 52.4% of them were females) completed a questionnaire regarding previous orthodontic treatment and the type of appliance used. Their oral cavity was also inspected. The DAI and ICON indices were used for the assessment of malocclusion prevalence.

RESULTS

The subjects with mixed dentition had a greater need for orthodontic treatment, when compared to subjects with permanent dentition, when using the DAI index (p<0.001). When using the ICON index, 11.7% of subjects with mixed dentition had very severe malocclusion, as opposed to 5.8% of subjects with permanent dentition. The DAI and ICON scores correlated positively linearly (r=0.521; p<0.001). A higher prevalence of both gingivitis and caries was recorded more often in boys; caries more often in the group with the mixed dentition, and gingivitis in the group with permanent dentition (p<0.05).

CONCLUSION

The DAI and ICON indices have moderate agreement in assessment of malocclusion severity scores. One third of all schoolchildren with various degrees of both ICON and DAI indices have gingivitis, and half of them have caries.

Orthodontic Fixed Appliance and Periodontal Status: An Updated Systematic Review

Background:

Periodontal implications of orthodontic therapy are frequent, gingival and periodontal conditions need to be evaluated for every appointment. Several studies have analyzed the effects of fixed appliance on periodontal health.

Objective:

To evaluate whether there is updated scientific evidence on the relationship between fixed orthodontic therapy and periodontal health.

Methods:

A literature search was performed using the Pubmed and Cochrane databases and manual search; the search was carried out using the keywords “orthodontic” and “periodontal”. Articles published only in the English language from January 1997 to April 2017 were included. The inclusion criteria were: RCTs, cohort studies, cross-sectional studies and case-control studies only in English language; only studies on humans, with a minimum sample size of 20 patients and no restriction in terms of patient ages; orthodontic fixed appliances placed into the buccal tooth surface; standardization and training in oral hygiene; Periodontal Index (PI), Gingival Index (GI), Bleeding on Probing (BOP), Pocket Probing Depth (PPD), at least at baseline (before appliance was placed) and after follow up (with a minimum period of 3 months). The exclusion criteria were as follows: absence of baseline data before fixed appliances was placed; patients with systemic diseases, periodontal disease or craniofacial anomalies; removable appliances or orthodontic appliance on the lingual dental surface; and no standardization or training in oral hygiene.

Studies were selected by abstract and title; then, inclusion and exclusion criteria were applied. The studies that satisfied the inclusion criteria were evaluated and classified as having low, moderate or high methodology quality.

Results:

Fifty-five records were reviewed on the basis of title and abstract. After full-text reading, 47 full texts were excluded, and 3 articles were classified as having low methodological quality and 5 as having moderate methodological quality.

Conclusions:

The present systematic analysis suggests that there is moderate scientific evidence that a fixed appliance influences periodontal status; no article reported a high score.

Cytokine profile changes in gingival crevicular fluid after placement different brackets types

OBJECTIVE

The aim of this study was to examine the relationship between bracket design and ratio of five proinflammatory cytokine, in gingival crevicular fluid (GCF), and bacterial adhesion without tooth movement influence.

DESIGN

The sample was comprised of 20 participants, aged 11 to 15 years old (mean age: 13.3 years±1.03). A conventional Gemini™ metallic bracket and two self-ligating brackets, In-Ovation^®R and SmartClip™, were bonded to the maxillary incisors and canines. GCF was collected using a standard filter paper strip before and 60days after bonding. The cytokine levels (IL-12, IL-1α, IL-1β, IL-6 and TNF-α) were performed by the LUMINEX assay. The levels of the red and orange bacterial complexes were analyzed by the Checkerboard DNA-DNA hybridization. The data of cytokine and bacterial complexes were carried out using the non-parametric tests at 5% of significance level.

RESULTS

Increased cytokine levels were observed. However, only the SmartClip™ group showed a significantly increased level of TNF-α (p=0.046). The SmartClip™ brackets group presented higher levels of red complex bacteria.

CONCLUSIONS

The bracket design affected cytokine levels and bacterial adhesion since it was observed that the proinflammatory cytokines released in GCF to the SmartClip™ group showed an increase in the TNF-α levels associated with higher bacterial levels, which possibly represents greater inflammatory potential. Thereby, the bracket design should be considered in patients with risk of periodontal disease and root resorption.

Effect of pH, fluoride and hydrofluoric acid concentration on ion release from NiTi wires with various coatings

Aim was to determine effect of pH, fluoride (F^-) and hydrofluoric acid concentration (HF) on dynamic of nickel (Ni²⁺) and titanium (Ti⁴⁺) ions release. Nickel-titanium wires with untreated surface (NiTi), rhodium (RhNiTi) and nitride (NNiTi) coating were immersed once a week for five min in remineralizing agents, followed by immersion to artificial saliva. Ion release was recorded after 3, 7, 14, 21 and 28 days. Pearson correlations and linear regression were used for statistical analysis. Release of Ni²⁺ from NiTi and NNiTi wires correlated highly linearly positively with HF (r=0.948 and 0.940, respectively); for RhNiTi the correlation was lower and negative (r=-0.605; p<0.05). The prediction of Ti⁴⁺ release was significant for NiTi (r=0.797) and NNiTi (r=0.788; p<0.05) wire. Association with F^- was lower; for pH it was not significant. HF predicts the release of ions from the NiTi wires better than the pH and F^- of the prophylactic agents.

Periodontal health in teenagers treated with removable aligners and fixed orthodontic appliances

OBJECTIVES

The purpose of this study was to explore the microbiological and periodontal changes occurring in adolescents during 12 months of orthodontic therapy with removable aligners and with fixed appliances.

MATERIAL AND METHODS

During the years 2012-2013, 50 teenagers aged 10-18 years with similar initial orthodontic conditions participated in this trial in a university clinic in northern Italy. After receiving professional oral hygiene and instructions on a standardized oral hygiene protocol, the adolescents were randomly assigned to either orthodontic treatment with traditional fixed brackets (n = 25) or to treatment with Invisalign® aligners (n = 25). Subgingival microbiological samples, probing depth (PD), plaque index (PI), and bleeding on probing (BOP) were obtained and documented from the mesiovestibular subgingival sulcus of the upper right first molar and left central incisor at the beginning of treatment and 3, 6, and 12 months later. Compliance with oral hygiene procedures, full mouth plaque score (FMPS), and full mouth bleeding score (FMBS) were assessed at the beginning of treatment and 12 months later. Two sample independent t-tests and the χ(2) test were used to study whether the indices of periodontal health differed in the teenagers due to the experimental conditions.

RESULTS

None of the patients was positive for the periodontal anaerobes analyzed. The PI, PD, BOP, FMPS, and FMBS scores were significantly lower and compliance with oral hygiene was significantly higher in the group treated with Invisalign® than in the group treated with fixed brackets.

CONCLUSION

Teenagers treated with removable appliances display better compliance with oral hygiene, less plaque, and fewer gingival inflammatory reactions than their peers with fixed appliances.

The effect of fixed appliances on oral malodor from beginning of treatment till 1 year

BACKGROUND

Orthodontic appliances can enhance plaque accumulation, and this can cause gingival inflammation. Halitosis of oral origin is associated with microbial metabolism on the tongue and in the saliva, dental plaque, and the amount of volatile sulfide-containing compounds. This study used a Halimeter to investigate fixed orthodontic therapy-associated increases in the oral malodor over a year.

METHODS

Thirteen orthodontic patients with Angle Class I malocclusions receiving fixed orthodontic therapy formed the study group, and 12 dental students without any dental treatment formed the control group. The Halimeter was used to examine oral malodor by detecting volatile sulfur compounds (VSC). Plaque index (PI), gingival index (GI), and probing pocket depth (PPD) were also measured in both groups. The subjects in the study group had one visit before the orthodontic treatment started and seven visits during orthodontic therapy (1, 3, 5, 7, 9, 11, and 13 months after bonding), while the subjects in the control group had three visits, once per subsequent month.

RESULTS

Oral malodor was significantly increased in the fixed orthodontic treatment group during treatment (p < .05). Increases were also observed in the PI, GI, and PPD measures (p < .05). The results of the control group were stable (p > .05).

CONCLUSION

Oral malodor increased during fixed orthodontic treatments and reached a critical level 7 months later.

Periodontal health in patients under conventional and lingual orthodontic therapies

AbstractObjectiveSome clinical periodontal health parameters were assessed comparatively in patients using conventional and lingual brackets.Material and methodA trained examiner registered the frequencies of visible plaque (VP), bleeding on probing (BOP), as well as the simplified oral hygiene (OHI-S) and modified gingival (MGI) indices in 83 subjects from two clinics. The effects of orthodontic treatments on periodontal health were analyzed using logistic regression (α = 0.05).ResultIn the conventional group, the frequency of visible plaque was significantly higher on the buccal surfaces of anterior (OR = 12.5) and maxillary posterior (OR = 3.6) teeth, p < 0.01. BOP in posterior teeth was also more frequent in this group, p < 0.05. The lingual group presented higher frequency of visible plaque on the lingual surfaces of anterior teeth (OR = 4.3; p = 0.0034). The conventional group had significantly higher frequencies of mild gingivitis in the buccal regions of anterior (OR = 9.0) and maxillary posterior (OR = 16.7) teeth, p < 0.05, and anterior papillae (OR = 9.0; p = 0.0003). On the other hand, the lingual group evidenced mild gingivitis more often in the lingual regions of anterior teeth (OR = 54.5), p < 0.01.ConclusionBased on the results of this study, the clinical periodontal health conditions may be considered acceptable for patients using both conventional and lingual brackets.

The Effect of Fixed Orthodontic Appliances and Fluoride Mouthwash on the Oral Microbiome of Adolescents - A Randomized Controlled Clinical Trial

While the aesthetic effect of orthodontic treatment is clear, the knowledge on how it influences the oral microbiota and the consequential effects on oral health are limited. In this randomized controlled clinical trial we investigated the changes introduced in the oral ecosystem, during and after orthodontic treatment with fixed appliances in combination with or without a fluoride mouthwash, of 10–16.8 year old individuals (N = 91). We followed several clinical parameters in time, in combination with microbiome changes using next-generation sequencing of the bacterial 16S rRNA gene. During the course of our study, the oral microbial community displayed remarkable resilience towards the disturbances it was presented with. The effects of the fluoride mouthwash on the microbial composition were trivial. More pronounced microbial changes were related to gingival health status, orthodontic treatment and time. Periodontal pathogens (e.g. Selenomonas and Porphyromonas) were highest in abundance during the orthodontic treatment, while the health associated Streptococcus, Rothia and Haemophilus gained abundance towards the end and after the orthodontic treatment. Only minor compositional changes remained in the oral microbiome after the end of treatment. We conclude that, provided proper oral hygiene is maintained, changes in the oral microbiome composition resulting from orthodontic treatment are minimal and do not negatively affect oral health.

Periodontal health status in patients treated with the Invisalign(®) system and fixed orthodontic appliances: A 3 months clinical and microbiological evaluation

OBJECTIVE

The aim of this prospective study was to compare the periodontal health and the microbiological changes via real-time polymerase chain reaction (PCR) in patients treated with fixed orthodontic appliances and Invisalign(®) system (Align Technology, Santa Clara, California).

MATERIALS AND METHODS

Seventy-seven patients were enrolled in this study and divided into three groups (Invisalign(®) group, fixed orthodontic appliances group and control group). Plaque index, probing depth, bleeding on probing were assessed. Total biofilm mass and periodontal pathogens were analyzed and detected via real-time PCR. All these data were analyzed at the T0 (beginning of the treatment) T1 (1-month) and T2 (3 months); and statistically compared using the Mann-Whitney test for independent groups.

RESULTS

After 1-month and after 3 months of treatment there was only one sample with periodontopathic anaerobes found in patient treated using fixed orthodontic appliances. The Invisalign(®) group showed better results in terms of periodontal health and total biofilm mass compared to the fixed orthodontic appliance group. A statistical significant difference (P < 0.05) at the T2 in the total biofilm mass was found between the two groups.

CONCLUSION

Patients undergoing orthodontic treatment with the Invisalign(®) System show a superior periodontal health in the short-term when compared to patients in treatment with fixed orthodontic appliances. Invisalign(®) should be considered as a first treatment option in patients with risk of developing periodontal disease.

A prospective, randomized placebo-controlled clinical trial on the effects of a fluoride rinse on white spot lesion development and bleeding in orthodontic patients

Demineralizations around orthodontic brackets are a main disadvantage of orthodontic treatment. Several methods have been advocated to prevent their development, such as fluoride rinses or varnishes. In this randomized clinical trial, a fluoride rinse (a combination of sodium fluoride and amine fluoride) was compared with a placebo rinse, to be used every evening after toothbrushing. A total of 81 participants (mean age: 13.3 yr) completed the study (mean treatment period: 24.5 months). Demineralizations, measured using quantitative light‐induced fluorescence and the decayed, missing, and filled surfaces (DMFS) index, were assessed before treatment (baseline) and around 6 wk after debonding (post treatment). Bleeding scores were measured at baseline, and during and post treatment. The incidence rate ratio for demineralizations was 2.6 (95% CI: 1.1–6.3) in the placebo group vs. the fluoride group. In the fluoride group, 31% of participants developed at least one demineralization, compared with 47% in the placebo group. Relative to baseline, gingival bleeding increased significantly in the placebo group 1 yr after the start of treatment and onwards. For the fluoride group, bleeding scores during treatment were not different from those at baseline. In conclusion, using a fluoride rinse helps to maintain better oral health during fixed appliance treatment, resulting in fewer demineralizations.

Comparative three-dimensional analysis of initial biofilm formation on three orthodontic bracket materials

INTRODUCTION

The purpose of the present study was to investigate and compare early biofilm formation on biomaterials, which are being used in contemporary fixed orthodontic treatment.

METHODS

This study comprised 10 healthy volunteers (5 females and 5 males) with a mean age of 27.3 +-3.7 years. Three slabs of different orthodontic materials (stainless steel, gold and ceramic) were placed in randomized order on a splint in the mandibular molar region. Splints were inserted intraorally for 48 h. Then the slabs were removed from the splints and the biofilms were stained with a two color fluorescence assay for bacterial viability (LIVE/DEAD BacLight-Bacterial Viability Kit 7012, Invitrogen, Mount Waverley, Australia). The quantitative biofilm formation was analyzed by using confocal laser scanning microscopy (CLSM).

RESULTS

The biofilm coverage was 32.7 ± 37.7% on stainless steel surfaces, 59.5 ± 40.0% on gold surfaces and 56.8 ± 43.6% on ceramic surfaces. Statistical analysis showed significant differences in biofilm coverage between the tested materials (p=0.033). The Wilcoxon test demonstrated significantly lower biofilm coverage on steel compared to gold (p=0.011). Biofilm height on stainless steel surfaces was 4.0 ± 7.3 μm, on gold surfaces 6.0 ± 6.6 μm and on ceramic 6.5 ± 6.0 μm. The Friedman test revealed no significant differences between the tested materials (p=0.150). Pairwise comparison demonstrated significant differences between stainless steel and gold (p=0.047).

CONCLUSION

Our results indicate that initial biofilm formation seemed to be less on stainless steel surfaces compared with other traditional materials in a short-term observation. Future studies should examine whether there is a difference in long-term biofilm accumulation between stainless steel, gold and ceramic brackets.

Anaerobic culture to detect periodontal and caries pathogens

BACKGROUND

Anaerobic culture has been critical in our understanding of the oral microbiotas.

HIGHLIGHT

Studies in advanced periodontitis in the 1970's revealed microbial complexes that associated with different clinical presentations. Taxonomy studies identified species newly-observed in periodontitis as Aggregatibacter (Actinobacillus) actinomycetemcomitans, Campylobacter (Wolinella) rectus and other Campylobacter species, and Tannerella (Bacteroides) forsythia. Anaerobic culture of initial periodontitis showed overlap in the microbiota with gingivitis, and added Selenomonas noxia and Filifactor alocis as putative periodontal pathogens. Porphyromonas gingivalis and T. forsythia were found to be associated with initial periodontitis in adults. The dominant microbiota of dental caries differs from that of periodontitis. The major cariogenic species are acidogenic and acid tolerant species particularly Streptococcus mutans, and Lactobacillus and Bifidobacterium species. Anaerobic culture of severe early childhood caries revealed a widely diverse microbiota, comparable to that observed using cloning and sequencing. The PCR-based cloning approach, however, underestimated Actinobacteria compared with culture. Only a subset of the caries-associated microbiota was acid tolerant, with different segments of the microbiota cultured on blood agar compared to a low pH acid agar. While the major caries-associated species was S. mutans, a new species, Scardovia wiggsiae, was significantly associated with early childhood caries. Higher counts of S. wiggsiae were also observed in initial white spot carious lesions in adolescents.

CONCLUSION

In periodontitis and dental caries, anaerobic culture studies of advanced disease provided a comprehensive analysis of the microbiota of these infections. Anaerobic culture highlighted the limitation of PCR with standard primers that underestimate detection of Actinobacteria.

Short-term effect of removal of fixed orthodontic appliances on gingival health and subgingival microbiota: a prospective cohort study

OBJECTIVE

The aim of this prospective longitudinal study was to assess and compare the microbiological and clinical parameters of patients wearing a fixed orthodontic appliance, as opposed to 10 days after the bracket had been removed following treatment.

MATERIALS AND METHODS

In total, 122 patients participated in this study; 61 of the subjects were assessed at baseline (wearing a fixed orthodontic appliance: T1) and 10 days after bracket removal (T2). The other 61 individuals had never worn an orthodontic appliance before and these subjects served as controls (CT). Subgingival plaque samples were assessed for bleeding on probing (GBI) and plaque index (VPI). PCR of 16s rDNA, followed by reverse species-specific hybridization for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola were performed. A descriptive analysis was conducted; chi-squared, Student's matched and unmatched t-tests, the point biserial correlation coefficient and the McNemar test were used to test for differences between groups (p < 0.05).

RESULTS

The GBI and VPI clinical parameters showed statistical differences (p < 0.05) between T1-T2, T1-CT and T2-CT. The prevalence of T. denticola had significantly decreased (p = 0.039) 10 days after appliance removal. At T2, a significant positive correlation was found between GBI and A. actinomycetemcomitans (p < 0.01) and between clinical parameters and P. intermedia. In patients without a fixed orthodontic appliance (T2 and CT), there was a significant positive correlation between T. forsythia and VPI.

CONCLUSION

Local factors associated with the wearing of a fixed orthodontic appliance influence changes in subgingival plaque that leads to more inflammation and bleeding.

The effects of different orthodontic appliances upon microbial communities

OBJECTIVES

Orthodontic appliances can promote accumulation of dental plaque, with associated enamel decalcification or gingival inflammation. The aim of this study was to examine longer-term microbiological changes during orthodontic treatment with fixed appliances.

MATERIALS AND METHODS

Twenty-four orthodontic patients aged 11-14 years undergoing fixed appliance therapy were recruited into the study. Each was randomized for cross-mouth assignment of molar bands and bonded molar tubes to contralateral quadrants of the mouth. All patients received self-ligating brackets, but again using randomization, one upper lateral incisor bracket (left or right) also received an elastomeric ligature. Plaque samples from the molars and upper lateral incisors were obtained at intervals during treatment and up to 1 year after appliance removal. Denaturing gradient gel electrophoresis and 16S rDNA microarray were used to compare plaque microbial fingerprints.

RESULTS

Plaque populations changed within 3 months of commencing treatment at all sites. The greatest differences in plaque composition were seen with self-ligating brackets with an elastomeric ligature. Post-treatment plaque associated with both types of molar attachment contained increased levels of periodontal pathogens Porphyromonas gingivalis, Tannerella forsythia, and Eubacterium nodatum, while Campylobacter rectus, Parvimonas micra, and Actinomyces odontolyticus were also elevated with bonds.

CONCLUSIONS

The results suggest that orthodontic treatment may cause sustained changes in plaque microbiotas and that molar bond-associated plaque may have raised disease potential.

Microbial changes in subgingival plaque and polymicrobial intracellular flora in buccal cells after fixed orthodontic appliance therapy: a preliminary study

The oral ecosystem is strictly related to a balance maintained by specific niches recognized as sites, where oral bacteria can metabolize avoiding the immune system response. The oral bacteria species that colonize the ecological niches vary during fixed orthodontic treatment, with a prevalence of periodontal bacterial species. Qualitative analysis of five periodontal pathogens was used to investigate the microbial colonization rate in the crevice and buccal epithelial cells. The presence of inadequate oral hygiene was considered as a modulation variable for microbial colonization. Statistical analysis was performed by Fisher's exact test, ANOVA, and Pearson correlation. A P value lower than 0.05 was assumed as statistically significant. Tannerella forsythia was the only periodontal pathogen detected with a statistically admissible frequency. The positivity for Tannerella forsythia was correlated to sampling time and oral hygiene motivation. In buccal epithelial cells, both factors contributed to microbial decrease (P < 0.05), whereas, in crevice, oral hygiene motivation promoted a decrease in the microbial colonization rate (P < 0.05). According to microbiological findings, it is possible to identify how correct motivation for oral hygiene is more than enough to modulate or to avoid an upset of the oral ecosystem balance in early stages of orthodontic treatment.

Three-dimensional analysis of initial biofilm formation on polytetrafluoroethylene in the oral cavity

AIM

There is published evidence that polytetrafluoroethylene (PTFE) exhibits beneficial surface characteristics by means of long-term biofilm accumulation. The purpose of this study was to investigate and compare early biofilm formation on polytetrafluoroethylene, ceramic-reinforced polytetrafluoroethylene and as the control group, stainless steel.

MATERIALS AND METHODS

This study comprised 10 healthy volunteers (5 females and 5 males) with a mean age of 27.3 ± 3.7 years. Three different slabs (two PTFE coatings: one pure and one ceramic-reinforced polytetrafluoroethylene, and stainless steel) were placed in random order on a splint in the mandibular molar region. Intraoral splints were inserted for 48 h. After 48 h, we removed the slabs from the splints and stained the biofilm with a two-color fluorescence assay for bacterial viability (LIVE/DEAD BacLight-Bacterial Viability Kit 7012, Invitrogen, Mount Waverley, Australia). The amount of biofilm accumulation was assessed using confocal laser scanning microscopy (CLSM).

RESULTS

The biofilm surface coverage was 55.8 ± 39.8% on pure PTFE-coated probes, 55.9 ± 35.0% on ceramic-reinforced PTFE-coated probes, and 33.3 ± 37.8% on stainless steel. The differences among the three groups were not significant (p = 0.301). Biofilm depth was 5.6 ± 5.4 μm on pure PTFE-coated probes, 5.2 ± 3.8 μm on ceramic-reinforced PTFE-coated probes, and 2.4 ± 2.9 μm on stainless steel. The Friedman test revealed a significant difference in biofilm depth (p = 0.002). Pairwise comparison of biofilm accumulation yielded a significant difference between pure PTFE and ceramic-reinforced PTFE compared to stainless steel (p = 0.017; p = 0.005).

CONCLUSION

Our results indicate that the beneficial surface characteristics of PTFE coatings by reducing long-term biofilm are not a result of inhibiting initial bacterial adhesion.

Co-regulation of LPS and tensile strain downregulating osteogenicity via c-fos expression

AIMS

Orthodontic forces are known to aggravate inflammation-induced destruction of the periodontium, but the underlying mechanism has not been elucidated. The present study investigates how inflammation and forces co-regulate periodontium damage.

MAIN METHODS

Cultures of MC3T3-E1 osteoblasts were pre-treated with conditioned medium from RAW264.7 macrophages exposed to 100ng/ml Porphyromonas gingivalis (Pg)-LPS. Conditioned medium was analyzed by ELISA for interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Osteoblasts were then subjected to tensile strain (0.5Hz; 1000μ or 3000μ) for 0min, 5min, 15min, 30min, 1h, 3h, and 6h. The cultures were analyzed for mRNA and protein levels of c-fos. Cells were also analyzed for alkaline phosphatase (ALP) activity.

KEY FINDINGS

(Pg)-LPS stimulated the secretion of all three cytokines from RAW264.7 cells in a dose- and time-dependent manner. Medium from (Pg)-LPS stimulated cells induced a 10-fold increase in c-fos expression, which decreased to a 4-fold plateau after 3h. In contrast, ALP activity of control osteoblasts decreased during the first 60min, then recovered over the next 4h. Pretreatment with conditioned medium generated the same initial decrease during tensile strain but prevented the recovery.

SIGNIFICANCE

Our study showed, for the first time, that the inhibitory effect of inflammation and tensile strain on osteogenicity is associated with the upregulation in c-fos expression. In addition, inflammation may reduce the ability of osteoblasts to restore their osteogenic capacity during sustained tensile stress and contribute to periodontium damage.

Periodontal status of adult patients treated with fixed buccal appliances and removable aligners over one year of active orthodontic therapy

OBJECTIVE

To compare the periodontal status of adults treated with fixed buccal orthodontic appliances vs removable orthodontic aligners over 1 year of active therapy.

MATERIALS AND METHODS

The study population consisted of 42 subjects; 22 treated with fixed buccal orthodontic appliances and 20 treated with removable aligners. Clinical indices recorded included: plaque index (PI), gingival index (GI), bleeding on probing (BOP), and probing pocket depth (PPD). Plaque samples were assessed for hydrolysis of N-benzoyl-DL-arginine-naphthylamide (BANA test). Indices and BANA scores were recorded before treatment and at 6 weeks, 6 months, and 12 months after initiation of orthodontic therapy.

RESULTS

After 6 weeks, only mean PPD was greater in the fixed buccal orthodontic appliance group. However, after 6 months, the fixed buccal orthodontic appliance group had significantly greater mean PI, PPD, and GI scores and was 5.739 times more likely to have a higher BANA score. After 12 months, the fixed buccal orthodontic appliance group continued to have greater mean PI, GI, and PPD, while a trend was noted for higher BANA scores and BOP.

CONCLUSIONS

These results suggest treatment with fixed buccal orthodontic appliances is associated with decreased periodontal status and increased levels of periodontopathic bacteria when compared to treatment with removable aligners over the 12-month study duration.

Risk factors for periodontal changes in adult patients with banded second molars during orthodontic treatment

OBJECTIVE

To identify the risk factors for periodontal changes in adult patients during orthodontic treatment by evaluating the periodontal status of banded second molars using the gingival index (GI).

MATERIAL AND METHODS

The sample consisted of 100 adult patients divided into two groups: the Orthodontics group, undergoing corrective treatment with fixed appliances and bands cemented to the four second molars, and the Control group, with no prior history of orthodontic treatment, age and sex matched. Group GI values were compared using the Wilcoxon test. Additionally, a multivariate logistic regression was performed to study the risk factors for increases in the GI.

RESULTS

Individuals in the Orthodontics group showed a significantly higher GI than those in the Control group. Logistic regression revealed that among the risk factors found to increase GI, the following proved significant (in order of importance): plaque index, subgingival encroachment of the cervical margins of bands, probing depth, and length of orthodontic treatment.

CONCLUSIONS

Banded second molars of adult patients during orthodontic treatment showed more clinical signs of gingival inflammation than those of untreated individuals. Moreover, major risk factors identified included the presence of plaque and the presence of subgingival band margins.

Association between dental floss use and gingival conditions in orthodontic patients

INTRODUCTION

Evidence comparing periodontal conditions in orthodontic patients who regularly use or do not use dental floss is scarce.

METHODS

The subjects were 330 patients who had been under fixed orthodontic treatment for at least 6 months. They were examined by 1 calibrated examiner for plaque and gingival indexes, probing pocket depths, clinical attachment losses, and excessive resin around brackets. Socioeconomic background, time with orthodontic appliances, and use of dental floss were assessed in interviews. Unadjusted and multiple logistic regression analyses were used to assess the associations.

RESULTS

The results demonstrated statistically significant higher means of plaque index, gingival index, pocket probing depth, and clinical attachment loss for nonusers of dental floss. Intragroup analyses showed higher means of these parameters in proximal sites and posterior teeth, compared with their counterparts' buccal and lingual sites and anterior teeth, respectively. After multivariate analysis, male subjects (P = 0.044) with a household income less than 5 national minimum wages (P = 0.044), and nonusers of dental floss (P = 0.000) showed higher probabilities of gingival bleeding (>30%) than did their counterparts.

CONCLUSIONS

Orthodontic patients who use dental floss regularly have somewhat better gingival conditions than those who do not use floss.

Comparative analysis of long-term biofilm formation on metal and ceramic brackets

OBJECTIVE

To test the null hypothesis that stainless steel and ceramic brackets show no differences in biofilm adhesion.

MATERIALS AND METHODS

Twenty adolescents (6 boys, 14 girls) who had received fixed orthodontic therapy for 18.9 ± 3.2 months were divided into a metal and a ceramic bracket group. Thirty brackets per group were taken from central incisors, canines, and second premolars and quantitatively analyzed for biofilm coverage with the Rutherford backscattering detection method. Five micrographs were obtained per bracket with views from the buccal, mesial, distal, gingival, and occlusal aspects, resulting in a total of 300 images. Biofilm formation between groups was compared using the Mann-Whitney U-test (α = .05).

RESULTS

Total biofilm formation was 12.5% ± 5.7% (3.3 ± 1.6 mm(2)) of the surface on metal and 5.6% ± 2.4% (1.5 ± 0.6 mm(2)) on ceramic brackets. Differences between groups were statistically significant (P < .05). A pairwise comparison of biofilm formation revealed significantly lower biofilm formation on ceramic brackets with respect to intraoral location (central incisor, canine, second premolar) and bracket surface (buccal, mesial, distal).

CONCLUSIONS

The hypothesis was rejected. The results indicate that ceramic brackets exhibit less long-term biofilm accumulation than metal brackets.