Failure frequency of fixed mandibular retainers after pre-treatment of the enamel surface with pumice versus sandblasting-a randomized controlled trial

BACKGROUND/OBJECTIVES

To compare retainer survival, periodontal health, and caries implications of fixed lower retainers bonded after pre-treatment of the enamel surface with either pumice or sandblasting.

TRIAL DESIGN

Two-arm parallel-group, two-center randomized controlled clinical trial.

METHODS

One hundred sixty patients (101 females, 59 males, mean age: 17.9) requiring mandibular retainers were consecutively recruited. Patients were randomly allocated to have pre-treatment of the enamel surface with either pumice (n = 80) or sandblasting (n = 80). The primary outcome was retainer survival at 3 (T1) and 12 months (T2) control. Secondary outcomes were carious lesions and periodontal health: plaque index (PI), gingival index (GI), calculus index (CI), and probing depth (PD). The randomization sequence was generated using an online randomization and allocation concealment was secured by contacting the sequence generator for treatment assignment. Blinding was not possible at T0 due to the nature of the intervention. Statistical analyses were carried out using the t-test, Fisher's exact test, repeated measure analysis of variance, and log rank test.

RESULTS

Overall, the risk of bonding failure at T1 was 6.7 per cent and at T2 6.9 per cent. There were no statistically significant differences in failure rate between the two groups, neither at T1 (P = 1.000) nor at T2 (P = 0.360). No statistically significant differences were found for the intercanine periodontal indices GI, PI, CI, PD, and caries between the two groups at T0 and T1. At T2, significantly more gingivitis and plaque were seen in the sandblasting group (P = 0.05 and P = 0.047, respectively) compared with the pumice group. Calculus increased during the follow-up period in both groups (P ≤ 0.001) as well as plaque levels (P ≤ 0.001 and P = 0.025, respectively). No harm was reported.

CONCLUSIONS

Enamel sandblasting prior to bonding mandibular retainers is not better at preventing bonding failure.

REGISTRATION

275767 (https://www.researchweb.org/is/sverige).

Comparison of pain intensity and impacts on oral health-related quality of life between orthodontic patients treated with clear aligners and fixed appliances: a systematic review and meta-analysis

OBJECTIVE

This study aimed to compare the pain intensity and impacts on oral health-related quality of life (OHRQoL) between orthodontic patients treated with clear aligners (CAs) and fixed appliances (FAs).

METHODS

A systematic search was conducted up to December 2022 using PubMed, Web of Science, Cochrane Central Register of Controlled Trials, and Embase. Randomized controlled trials (RCTs) and prospective non-randomized controlled trials (non-RCTs) comparing pain intensity or OHRQoL between patients treated with CAs and FAs were included. The risk of bias (RoB) of individual studies was evaluated using the Cochrane RoB tool 2.0 and ROBINS-I tool for RCTs and non-RCTs, respectively. Further, meta-analyses were separately conducted for each included study using the total oral health impact profile (OHIP)-14 and visual analog scale (VAS) scores to evaluate OHRQoL and pain intensity, respectively.

RESULTS

Overall, 12 studies (5 RCTs and 7 non-RCTs) were included in the study. Subgroup analyses conducted according to the total OHIP-14 scores revealed that patients treated with CAs had higher OHRQoL at 1 week, 1 month, and 6 months of the treatment. Meanwhile, subgroup analyses conducted according to the VAS scores revealed that pain levels were lower in the CA group only at 3 and 4 days of the treatment.

CONCLUSIONS

Patients treated with clear aligners had higher OHRQoL than those treated with fixed appliances during orthodontic treatment. However, OHRQoL appeared to be similar between the two groups at the end of the treatment. Moreover, patients treated with clear aligners experienced lesser pain than those treated with fixed appliances on the third and fourth day after the initial treatment. The difference in pain intensity between the two treatment modalities was not noted at other time points.

Impact of fixed orthodontic appliances on blood count and high-sensitivity C-reactive protein levels: A prospective cohort study

INTRODUCTION

The aim was to elucidate the magnitude of alterations in systemic blood counts in healthy patients during the first 14 days after fixed orthodontic appliance placement.

METHODS

This prospective cohort study consecutively included 35 White Caucasian patients starting orthodontic treatment with fixed appliances. The mean age was 24.48 ± 6.68 years. All patients were physically and periodontally healthy. Blood samples were collected at 3 time points: (1) baseline (exactly before the placement of appliances), (2) 5 days after bonding, and (3) 14 days after baseline. Whole blood and erythrocyte sedimentation rates were analyzed in automated hematology and erythrocyte sedimentation rate analyzer. Serum high-sensitivity C-reactive protein levels were measured by the nephelometric method. Standardized sample handling and patient preparation procedures were adopted to reduce preanalytical variability.

RESULTS

A total of 105 samples were analyzed. All clinical and orthodontic procedures were performed without complications or side effects during the study period. All laboratory procedures were performed per protocol. Significantly lower white blood cell counts were detected 5 days after bracket bonding, compared with baseline (P <0.05). Hemoglobin levels were lower at 14 days than baseline (P <0.05). No other significant shifts or alteration patterns were observed over time.

CONCLUSIONS

Orthodontic fixed appliances led to a limited and transient change in white blood cell counts and hemoglobin levels during the first days after bracket placement. The fluctuation of high-sensitivity C-reactive protein levels was not significant, demonstrating a lack of association between systemic inflammation and orthodontic treatment.

Inflammatory parameters and color alterations of dental bleaching in patients wearing fixed orthodontic appliance: a randomized clinical trial

BACKGROUND

Many orthodontic patients request dental bleaching during orthodontic treatment to achieve a faster aesthetic resolution, however, no attention has been paid to the inflammatory processes that can occur when both therapies are indicated together. So, this clinical trial evaluated the inflammatory parameters and color alterations associated with dental bleaching in patients wearing a fixed orthodontic appliance.

METHODS

Thirty individuals aged between 18 and 40 years were equally and randomly allocated into three groups: FOA (fixed orthodontic appliance), BLE (dental bleaching), and FOA + BLE (fixed orthodontic appliance + dental bleaching). The orthodontic appliances and the bleaching procedures were performed in the maxillary premolars and molars. For dental bleaching a 35% hydrogen peroxide was used. The gingival crevicular fluid (GCF) and nitric oxide (NO-) levels were evaluated at different time-points. Color evaluation was performed using an Easyshade spectrophotometer at baseline (FOA, FOA + BLE, BLE), one month after (FOA + BLE) and 21 days after appliance removing (FOA + BLE and FOA groups), in each tooth bleached. The ANOVA and Tukey's tests, with a significance level of 5%, were used for statistical analysis.

RESULTS

The GCF volume in the FOA + BLE and FOA groups significantly increased at the time points evaluated (p < 0.001); however, this did not occur in the BLE group (p > 0.05). On the other hand, NO- levels significantly decreased during dental bleaching with or without fixed orthodontic appliances (FOA + BLE and BLE groups; p < 0.05), while no significant changes were observed in the FOA group (p > 0.05). Significant changes in color were observed in the FOA + BLE and BLE groups compared to in the FOA group (p < 0.01). However, the presence of fixed orthodontic appliance (FOA + BLE) negatively affected the bleaching efficacy compared to BLE group (p < 0.01).

CONCLUSIONS

Dental bleaching did not increase the inflammatory parameters in patients wearing fixed orthodontic appliance. However, in the presence of orthodontic appliances, the bleaching efficacy was lower than that of bleaching teeth without orthodontic appliances.

TRIAL REGISTRATION

RBR-3sqsh8 (first trial registration: 09/07/2018).

Oxidative stress and genotoxicity in oral epithelial cells from subjects undergoing orthodontic treatment with fixed appliances

OBJECTIVES

The objective of this work was to evaluate the impact of fixed orthodontic appliances on oxidative stress (OS) and genotoxicity from oral epithelial cells.

MATERIALS AND METHODS

Samples of oral epithelial cells were obtained from fifty-one healthy voluntary subjects who had an indication for orthodontic treatment. The samples were obtained before treatment and after 6 and 9 months of treatment. OS was evaluated by quantitating 8-hydroxy-2'deoxyguanosine (8-OHdG) and by performing relative gene expression with antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). DNA degradation and instability were evaluated by multiplex polymerase chain reaction (PCR) and fragment analysis for human identification.

RESULTS

The quantitation results showed that 8-OHdG increased during treatment, although this increase was not statistically significant. SOD increased by 2.5- and 2.6-fold after 6 and 9 months of treatment, respectively. CAT increased by threefold after 6 months of treatment, while after 9 months of treatment, the expression level decreased to a level similar to that before treatment. DNA degradation was found in 8% and 12% of DNA samples after 6 and 9 months of treatment, respectively, while DNA instability was detected in only 2% and 8% of DNA samples after 6 and 9 months of treatment, respectively.

CONCLUSIONS

The results showed that OS and genotoxicity slightly changed after treatment with a fixed orthodontic appliance; in addition, a biological adaptation response to the treatment may occur after 6 months.

CLINICAL RELEVANCE

OS and genotoxicity in the buccal cavity are risk factors for oral and systemic diseases. This risk may be reduced through antioxidant supplementation, by using thermoplastic materials, or by reducing the orthodontic treatment time.

Effects of fixed retainers on gingival recession - a 10-year retrospective study

OBJECTIVE

The aetiology of gingival recessions is not fully understood, and no evidence has yet emerged of a single predisposing factor that instigates this apical shift of the gingival margin. Nonetheless, both fixed retainers and orthodontic treatment have been cited as potential risk factors. The aim of this study was to assess the effects of orthodontic treatment and orthodontic fixed retainers on gingival recessions.

SUBJECTS AND METHODS

In total, 105 patients at the Department of Orthodontics at the University of Gothenburg who had undergone orthodontic treatment between 1995 - 2003 were included in this study. Intraoral photographs of the anterior segment and study casts acquired at baseline (pre-treatment), post-treatment and at the 10-year follow-up were used as recorded measurements of gingival recession and orthodontic treatment. At the 10-year follow-up, the patients were divided into two groups based on: long-term (10 years) presence of a fixed retainer [orthodontic treatment and retainer (OR) group; N = 76]; and short-term (<5 years) presence of a fixed retainer [orthodontic treatment (O) group; N = 57]. These groups were compared to a control group (C) of untreated subjects (N = 29).

RESULTS

In the anterior segment, gingival recessions were not present at baseline and post-treatment between the two orthodontically treated groups. At the 10-year follow-up, there was no statistically significant difference between the two orthodontically treated groups and the controls.

CONCLUSIONS

Orthodontic treatment per se does not increase the risk for gingival recessions, nor does the use of fixed retainers following orthodontic treatment.

Morphological Characteristics and Prevention of Tooth Enamel Demineralization during Orthodontic Treatment with Non-Removable Appliances

Despite the large number of studies on the effect of braces on teeth, there is no information on the dynamics of the state of the ultrastructure of the hard tissues of teeth during orthodontic treatment. The purpose of this study is to examine the state of the hard tissues of the teeth and carry out preventive measures to reduce the risk of complications in the process of orthodontic treatment using a non-removable device. Methods: For the in vitro study, 68 teeth were randomly divided into group A-no prophylactic treatment, and group B-treated with the fluorine varnish Tiefenfluorid. After 35 days, all the teeth were prepared for microscopic examination. The clinical study included 59 patients aged 12-17 years with orthodontic brackets. The split-mouth technique was used. The areas around the bracket of one-half of the oral cavity were treated with Tiefenfluorid every 6 months during the entire treatment period. The teeth of the second half of the oral cavity served as the control group. The data were processed in the SPSS19 package. Results: In vitro and clinical study results showed a statistically significant difference between the prophylactic and control groups of teeth in favor of the prophylactic group, where the statistical significance was p ≤ 0.01.

[Canine avulsion: An extreme complication of a fixed mandibular lingual retainer]

INTRODUCTION

The use of fixed retainers at the end of a course of orthodontic treatment has become standard practice. The main complication that can occur with fixed retainers is the detachment of the wire from one or more teeth. A less common complication is unwanted tooth movement.

METHOD

This article presents a patient with extreme tooth movement associated with a mandibular fixed retainer. Ten years after orthodontic treatment, a 26-year-old male sought treatment for post-orthodontic movement of the mandibular anterior six teeth. Despite the fixed retainer still being attached to all teeth, the apex of the right canine was completed avulsed labially. Severe labial recession was also present on the left lateral incisor. The canine was extracted, and the fixed retainer was removed. Significant root resorption identified on a panoramic radiograph contraindicated any further extensive orthodontic intervention.

DISCUSSION

This case highlights that clinicians and patients should be aware of this rare but serious complication.

Root resorption factors associated with orthodontic treatment with fixed appliances: A systematic review and meta-analysis

External apical root resorption (EARR) is a serious complication that should be avoided during orthodontic treatment; this pathology depends on multiple factors. Data from clinical studies should be assessed to determine the influence these factors have on the development of EARR. This systematic review aims to compare EARR produced by different factors (orthodontic systems, dental trauma, and dental vitality). The protocol was registered on the PROSPERO database. The search was performed on 5 databases. Accepted study designs included randomized controlled trials, nonrandomized clinical trials, and observational studies. Full-text articles from clinical studies of EARR associated with orthodontic treatment in English, Spanish, or Portuguese with no publication date restrictions were selected. Data from the studies, such as age, population, study groups, and outcome measures, were recorded. Multiple meta-analyses were performed with data from the included studies. Evidence suggests that EARR induced by orthodontic treatment is similar, regardless of the technique used. Evidence of the effect of previous dental trauma on EARR during orthodontic treatment is limited. There is less EARR associated with orthodontic treatment in endodontically treated teeth than in vital teeth. These conclusions should be considered with caution due to the low certainty of the evidence.

[Microbial Diversity and Community Analysis of Dental Plaques in Orthodontic Patients Wearing Invisible Appliances and Fixed Appliances]

Objective

To explore the microbial diversity and community structure of dental plaques in orthodontic patients with invisible appliances and fixed appliances and to study the differences.

Methods

Ten orthodontic patients wearing invisible appliances (I) and ten wearing fixed appliances (F) were recruited. Dental plaques were collected from both buccal (B) and lingual (L) sides. Based on 16S rDNA, 40 dental plaque samples were analyzed after Illumina sequencing.

Results

The microbial diversity, abundance and evenness of the FB group were significantly higher than those of the IB and IL groups (P<0.05), while the FL group showed substantial individual differences. The community structures were generally similar among the four groups, but significant differences in the relative abundance of some bacteria were found. The IB group showed higher abundances of Actinomycetes and Rosella (P<0.05), which were considered to be involved in dental caries and periodontal diseases. Some key communities showing significant differences were significantly enriched in the FB group, including Coprobacillus, Bifidobacterium, Enterobacterium, Lactobacillus, etc..

Conclusion

Dental plaques in patients wearing invisible appliances and fixed appliances showed significantly different microbial abundance, diversity and composition, which may be involved in orthodontic complications such as dental caries and periodontal diseases. Orthodontic patients need strengthened measures for oral hygiene maintenance, no matter what kind of appliances they wear.

Antimicrobial resistance of bacterial strains in patients undergoing orthodontic treatment with and without fixed appliances

OBJECTIVES

To identify microorganisms isolated from patients wearing fixed orthodontic appliances and to evaluate the resistance of isolated bacterial strains to different antimicrobials.

MATERIALS AND METHODS

Seventeen healthy patients wearing a fixed orthodontic appliance (group 1) and six nonwearers (group 2, control group) were evaluated. The biofilm that formed around the orthodontic brackets was collected, and the samples were then plated in a chromogenic medium (chromIDT, bioMérieux). Colony-forming units (CFUs) were isolated and inoculated in blood-agar medium. Automated biochemical tests (VITEK 2, bioMérieux) were carried out to identify the genus and species of the microorganisms and the resistance provided by 43 drugs (37 antibacterial and 6 antifungal).

RESULTS

The most prevalent microbial genera identified in group 1 were Streptococcus (24.0%), Staphylococcus (20.0%), Enterobacter (12.0%), Geobacillus (12.0%), and Candida (12.0%), and the most frequent species were Enterobacter cloacae complex (13.6%) and Staphylococcus hominis (13.6%). In group 2, the most prevalent genera were Streptococcus (57.1%), Staphylococcus (14.2%), Sphingomonas (14.2%), and Enterobacter (14.2%). With regard to antimicrobial resistance, 14 of 19 (74%) isolated bacterial strains were found to be resistant to at least 1 of the tested antimicrobials.

CONCLUSIONS

The findings of the present study suggest that patients undergoing orthodontic treatment with fixed appliances have a more complex biofilm with a higher level of bacterial resistance.

Quality of life in an adolescent orthodontic population: Invisalign versus fixed appliances

OBJECTIVES

To investigate adolescent orthodontic patient experiences and quality of life with fixed appliances compared to Invisalign.

MATERIALS AND METHODS

Adolescent patients in active treatment with Invisalign or fixed appliances for a minimum of 6 months were provided with the Child Oral Health Impact Profile-Short Form 19 questionnaire, along with additional items of interest that were assessed separately. Pearson's χ2 test was used to compare responses (P < .05), and unpaired t-tests (P < .05) were used to test for differences in mean satisfaction, quality of life, and domain scores.

RESULTS

In total, 74 patients (37 in each treatment group) participated. Overall, no significant differences were noted in the mean quality of life, satisfaction, or domain scores between the two groups. A significant difference was noted in the time taken to adjust to appliances, with the Invisalign group demonstrating faster adaptation. Additionally, the fixed appliance group was 3.8 times more likely to report missing school because of their appliance (95% confidence interval [CI]: 1.2, 12.5) and 2.7 times more likely to report having difficulty eating certain foods (95% CI: 1.1, 7.1). When the sample of females between the ages of 14 and 18 was analyzed, the Invisalign group reported feeling attractive more often than the fixed appliance group.

CONCLUSIONS

Both treatment groups were generally very satisfied with their treatment modality. The overall quality of life of adolescent orthodontic patients undergoing treatment with fixed appliances and Invisalign for a minimum of 6 months was similar.

Effects of orthodontic treatment with aligners and fixed appliances on speech

OBJECTIVES

To evaluate effects of orthodontic treatment with aligners and conventional fixed appliances on production of speech.

MATERIALS AND METHODS

This was a parallel, randomized clinical trial. Patients with Angle Class I malocclusion, moderate crowding, and no speech impairment were randomly allocated to two groups: patients with orthodontic aligners (OAs; n = 20; mean age = 23.60 ± 5.65 years) and those with conventional fixed appliances (n = 20; mean age = 20.56 ± 4.51 years) and treated at the University of North Parana's clinic in Londrina, Brazil. Evaluation of speech production was performed semiobjectively by a speech therapist (myofunctional orofacial examination) and subjectively (self-assessment) at five time points: baseline, immediately after insertion of appliances, and subsequently at 3, 30, and 180 days after insertion. For intergroup comparison, independent t, χ2, Fisher exact, and Mann-Whitney tests were used; for intragroup comparison, the Friedman test was applied (α = 5%).

RESULTS

In the semiobjective evaluation, patients with OAs exhibited a change in production of speech production, compared with patients with fixed appliances, immediately and 3 days after insertion of appliances (P < .001). Thirty days after insertion, the groups were similar (P = .487), an outcome that was unchanged at 180 days. However, in the self-assessments, patients in both groups reported significant speech difficulties immediately and 3 days after insertion of appliances, but such impairment was no longer perceived at 30 days or 180 days.

CONCLUSIONS

Although the speech therapist identified changes in speech production at the start of treatment in the OA group only, patient self-assessments demonstrated that orthodontic treatment, regardless of the type of appliance used, interfered with their perception of speech.

Assessment of salivary pro inflammatory cytokines profile level in patients treated with labial and lingual fixed orthodontic appliances

The secretions of certain cytokines, chemokines and growth factors are triggered by orthodontic appliances, which often affect the remodelling of periodontal tissues. Critical cumulative forces are applied by various types of orthodontic appliances to the periodontium. The secretion of such molecules is probably responsible, through molecular and cellular communications, for the optimal resorption of hard tissues in the periodontal setting, which therefore enables the coordination of multiple movements of tooth. This study assessed and compared a wide range of cytokines, cellular marker analysis and defensins present in the saliva samples of human subjected to orthodontic treatment with two different treatment modalities, i.e., conventional lingual and labial fixed orthodontic appliances. A total 40 samples of saliva were obtained, of which 20 were treated with traditional lingual appliances and 20 were treated with labial fixed appliances. After 21 days of treatment, all salivary samples were collected from the subjects. In order to analyse a broad range of soluble cytokine levels in saliva by flow cytometry, a bead-based immunoassay was performed. Cell surface markers were analysed by flow cytometry. Protein levels of saliva for defensins were quantified by ELISA. Non-significant differences were observed in the cytokine levels in the saliva except for the significant effects for CCL2, IL-17A and IL-6. Cellular markers CD45 and CD326 showed high percentage in conventional lingual samples. Defensin levels were found to be lower in conventional lingual patients. Subjects with conventional lingual appliances had significantly higher salivary protein levels of IL-1β, CCL2, IL17A, and IL-6, higher CD45+ and CD326+ cells and lower defensin levels than subjects with fixed labial appliances. The current study provided a clear basis for the development of innovative methods to aid in the improvement of various procedural treatments and orthodontic equipment of next generation.

A Prospective Cohort Study Assessing the Impact of Fixed Orthodontic Appliances on Saliva Properties and Oral Microbial Flora

PURPOSE

Orthodontic treatment may introduce a risk to the integrity of enamel due to plaque accumulation and colonisation by oral microbes. This prospective cohort study observed the effect of fixed, self-ligating orthodontic appliances on saliva properties and oral microbial flora. Materials and Methods: Thirty adolescent patients were recruited (13 female, 17 male, mean age 13.97 ± 2.07 years). Saliva samples were collected before placement of fixed orthodontic appliances (T0), and 4 (T1) and 12 (T2) weeks later. Salivary pH, flow rate and buffering capacity were recorded. All saliva samples were cultured on agar plates for 2 days. Salivary prevalence of Neisseria spp., streptococci, Staphylococcus aureus, coagulase-negative staphylococci and Candida albicans were assessed. Results: High buffering capacity was reported in 21 patients at T0, 22 patients at T1 and in 28 patients at T2. Saliva flow rate also increased over time (7.08 ml/5 min at T0, 7.93 ml/5 min at T1 and 8.35 ml/5min at T2). Mean pH was 7.63 at T0, 7.67 at T1 and 7.78 at T2. There was no evidence that either pH or the number of colonies of any of the microbial species changed over time. Conclusion: The increased buffering capacity of saliva as well as the salivary flow rate after initial bonding might be protective against the development of dental caries. Current microbial findings indicate that initiation of orthodontic treatment may not be associated with significant changes in oral microbial flora.

Impact of Aligners and Fixed Appliances on Oral Health during Orthodontic Treatment: A Systematic Review and Meta-Analysis

PURPOSE

To identify and assess differences in oral hygiene parameters in patients undergoing orthodontic treatment with clear aligners compared to fixed appliances.

MATERIALS AND METHODS

Published and unpublished literature was searched in seven databases until May 31st 2021. Representative keywords included 'orthodontic aligner', 'fixed appliance', 'oral hygiene', 'plaque index', 'caries'. Study selection, data extraction, risk of bias and certainty of evidence assessment were undertaken independently by three reviewers. Random effects meta-analyses with respective confidence intervals (95% CI) were conducted, where applicable.

RESULTS

A total of 882 unique records were screened, with a final number of 21 articles being eligible for qualitative synthesis, while 4 of those contributed to meta-analyses. Risk of bias was rated within the range of low to high or serious overall, while certainty of evidence was low to very low according to GRADE. For periodontal parameters, adults undergoing aligner orthodontic treatment presented summary plaque scores 0.58 lower than those treated with fixed appliances, within the first 6 to 12 weeks (4 studies: mean difference: -0.58; 95%CI: -0.82, -0.34; p < 0.001; I2 squared: 71.3%), while no evidence of difference was recorded for inflammation indices. Microbiologic parameters such as presence of S. mutans and lactobacilli were more pronounced in patients with fixed appliances for the first 3 to 6 months (synthesised data from 2 studies).

CONCLUSIONS

In the short-term after initiation of orthodontic treatment, patients treated with aligners and no additional attachments/adjuncts presented potentially higher levels of oral health overall. However, the evidence is supported by low to very low certainty.

The periodontal status of removable appliances vs fixed appliances: A comparative meta-analysis

BACKGROUND

Although several researchers have analyzed the dental identity of patients experience with corrective methods using fixed and removable appliances, the consequences stay debatable. This meta-analysis intended to verify whether the periodontal status of removable appliances is similar to that of the conventional fixed appliances.

METHODS

Relevant literature was retrieved from the database of Cochrane library, PubMed, EMBASE, and CNKI until December 2019, without time or language restrictions. Comparative clinical studies assessing periodontal conditions between removable appliances and fixed appliances were included for analysis. The data was analyzed using the Stata 12.0 software.

RESULTS

A total of 13 articles involving 598 subjects were selected for this meta-analysis. We found that the plaque index (PLI) identity of the removable appliances group was significantly lower compared to the fixed appliances group at 3 months (OR = -0.57, 95% CI: -0.98 to -0.16, P = .006) and 6 months (OR = -1.10, 95% CI: -1.60 to -0.61, P = .000). The gingival index (GI) of the removable appliances group was lower at 6 months (OR = -1.14, 95% CI: -1.95 to -0.34, P = .005), but the difference was not statistically significant at 3 months (OR = -0.20, 95% CI: -0.50 to 0.10, P = .185) when compared with that of the fixed appliances group. The sulcus probing depth (SPD) of the removable appliances group was lower compared to the fixed appliances group at 3 months (OR = -0.26, 95% CI: -0.52 to -0.01, P = .047) and 6 months (OR = -0.42, 95% CI: -0.83 to -0.01, P = .045). The shape of the funnel plot was symmetrical, indicating no obvious publication bias in the Begg test (P = .174); the Egger test also indicated no obvious publication bias (P = .1).

CONCLUSION

Our meta-analysis demonstrated that malocclusion patients treated with the removable appliances demonstrated a better periodontal status as compared with those treated with fixed orthodontic appliances. However, the analyses of more numbers of clinical trials are warranted to confirm this conclusion.

Impact of Treatment with Full-fixed Orthodontic Appliances on the Periodontium and the Composition of the Subgingival Microbiota

AIMS

The purpose of this study was to evaluate the impact of fullfixed orthodontic appliances on the periodontium in adult patients.

METHODS

Seventeen periodontally and systemically healthy subjects were selected from the Periodontal Clinic of Guarulhos University, 7 males and 10 females (mean age: 38.3 ± 6.3 years). The patients undergoing orthodontic treatment were submitted a clinical examination, a cone beam computed tomography at baseline and after 12 months of treatment. Subgingival biofilm samples were analyzed by Checkerboard DNA-DNA hybridization. Statistical analysis was performed by a Wilcoxon test.

RESULTS

The percentage of sites with visible plaque increased (p =0.003), but no significant reduction in marginal bone was observed. The mean periodontal pocket depth was reduced (p=0.001) and the clinical attachment level significantly improved (p =0.001). There was a significant reduction in the mean proportions of the Actinomyces sp and an increase in the orange complex species. The proportions of the red complex species remained unchanged.

CONCLUSIONS

In spite of increase in plaque accumulation no significant clinical or tomographic iatrogenic changes in periodontally healthy adults undergoing orthodontic full-fixed appliance treatment could be detected. The microbiological changes did not affect the periodontal parameters in monitored adult patients that received short period of orthodontic treatment.

Comparing the plaque-removal ability of a triple-headed toothbrush versus a conventional manual toothbrush in adolescents with fixed orthodontic appliances: A single-center, randomized controlled clinical trial

OBJECTIVE

The objective of this trial was to compare the plaque removal ability of a triple-headed toothbrush to a conventional manual toothbrush in adolescents with fixed orthodontic appliances.

MATERIALS AND METHODS

Sixty adolescent patients undergoing orthodontic treatment were randomly assigned to brush one time with either a conventional manual toothbrush or a triple-headed toothbrush. The main outcome was the post-brushing plaque index as measured by the Silness-Löe plaque index.

RESULTS

Sixty patients (mean age, 14.2; standard deviation, 1.65) were randomized in a 1:1 ratio to either a manual toothbrush group or a triple-headed toothbrush group. Baseline characteristics were similar between the two groups. There were no dropouts. The mean post-brushing plaque index was 0.84 (95% CI, 0.67-1.02; SD, 0.60) for the conventional manual toothbrush group, and 0.31 (95% CI, 0.13-0.49; SD, 0.48) for the triple-headed toothbrush group. There was a statistically significant difference in the mean plaque index of 0.53 (95% CI, 0.28-0.78; P<0.001) between the two groups after brushing. No harms were observed.

CONCLUSION

The results of this study indicate strong evidence that the triple-headed toothbrush leads to a significantly lower plaque index compared to the conventional manual toothbrush post-brushing.

Comparative evaluation of salivary microbial levels and periodontal status of patients wearing fixed and removable orthodontic retainers

INTRODUCTION

The purpose of this study was to compare and evaluate salivary microbial levels and periodontal status in patients using a fixed lingual retainer, a removable vacuum-formed retainer, or a Hawley retainer after orthodontic treatment with fixed appliances.

METHODS

Forty-five patients who finished their orthodontic treatment with fixed appliances and were about to start the retention phase were randomly divided into the following 3 groups of 15 individuals each: the fixed lingual retainer group, the vacuum-formed retainer group, and the Hawley retainer group. Periodontal measurements, such as the plaque index, gingival index, probing depth, and bleeding on probing, were obtained at the following 4 time points: at debonding (T0) and 1 week (T1), 5 weeks (T2), and 13 weeks (T3) after debonding. Saliva samples were collected 3 times in total: at T0, T2, and T3. A quantitative analysis for Streptococcus mutans and Lactobacillus casei was performed with the use of real-time polymerase chain reaction. The Kruskal-Wallis test and 1-way analysis of variance were used for the statistical comparisons of the groups.

RESULTS

No statistically significant difference in salivary S mutans and L casei levels was found among the 3 groups (P >0.05). They showed no statistically significant differences in plaque index, gingival index, bleeding on probing, and probing depth values (P >0.05). All periodontal parameters showed statistically significant decreases from T0 to T3 in all 3 groups (P <0.001). The S mutans and L casei levels were decreased significantly from T2 to T3 in the lingual retainer and Hawley retainer groups, whereas they decreased significantly from T0 to T3 in the vacuum-formed retainer group.

CONCLUSIONS

Fixed and removable orthodontic retainers do not differ in salivary S mutans and L casei levels and periodontal status. With all retainers, regardless of whether they are fixed or removable, oral hygiene improved after orthodontic treatment with fixed appliances.

Scope of antimicrobial photodynamic therapy in Orthodontics and related research: A review

BACKGROUND

The aim of the present study was to comprehensively review indexed literature regarding the potential role of antimicrobial photodynamic therapy (aPDT) in Orthodontics.

METHODS

Indexed databases were searched up to and including January 2019 using the following key words: (a) antimicrobial photodynamic therapy; (b) antimicrobial photodynamic chemotherapy; (c) orthodontic; and (d) orthodontics. Original (clinical and experimental) studies, case-reports, and case-series were included. Letters to the Editor, commentaries and review articles were excluded.

RESULTS

Out of the 29 studies identified in the initial search, 4 studies were processed for data extraction. Three studies were randomized clinical trials performed in humans and 1 study was experimental. Results from 2 studies showed that aPDT is effective in the treatment of gingival inflammation in patients undergoing orthodontic therapy (OT). One study showed that oral decontamination can be successfully performed using aPDT among patients undergoing OT. Results of the experimental study showed that aPDT helps in surface decontamination of orthodontic instruments.

CONCLUSION

There is insufficient evidence in indexed literature to justify the potential role of aPDT in OT. Hence, further studies are required in this regard.

Subgingival Microbial Changes During the First 3 Months of Fixed Appliance Treatment in Female Adult Patients

Although periodontal diseases during fixed appliance treatment are a common issue, few studies have focused on the clinical and microbial factors associated with orthodontic appliances. Hence, we investigated changes in the subgingival microbial community and their association with periodontal changes at the early stage of fixed appliance treatment. Subgingival plaques from ten female patients with fixed appliances were obtained at three time points: before, 1 month and 3 months after the placement of the brackets (T0, T1 and T2). The 16S rRNA gene sequencing was used to analyze the microbial community of the subgingival plaque. The Plaque Index (PI) and Gingival Bleeding Index (GBI) were also recorded. The GBI significantly increased at T2, and the PI showed a temporary increase without a significant difference. The alpha diversity indices were stable. However, the beta diversity was significantly higher at T2 compared to T0 and T1. The relative abundance of core microbiomes at the genus level was relatively stable. Four periodontal pathogens at the species level, including Prevotella intermedia (Pi), Campylobacer rectus (Cr), Fusobacterium nucleatum (Fn), and Treponema denticola (Td), increased without significant differences. The subgingival microbial community affected by fixed appliance treatment might cause transient mild gingival inflammation.

Association of Orthodontic Clear Aligners with Root Resorption Using Three-dimension Measurements: A Systematic Review

AIM

This paper aims to assess the evidence in the literature reporting orthodontically induced inflammatory root resorption (OIIRR) in treatment with orthodontic clear aligners using 3D measurements.

MATERIALS AND METHODS

Following preferred reporting Items for systematic reviews (PRISMA) statement, eight electronic databases were searched for relevant published and unpublished records. Data collected according to restricted inclusion and exclusion criteria.

RESULTS

A total of 236 articles were identified as relevant to our topic. Duplicates were excluded resulting in 226 papers, out of which 31 papers were relevant after screening titles and abstracts. Only 2 high-level evidence papers out of the 31 met the inclusion criteria for the qualitative synthesis.

CONCLUSION

Based on the available studies with high level of evidence in the literature, we conclude that orthodontic clear aligners are non-inferior to light-force fixed orthodontic appliances, and superior to heavy-force fixed orthodontic appliances in terms of the risk for developing apical root resorption.

CLINICAL SIGNIFICANCE

Orthodontists can be more assured about the low-risk of OIIRR associated with clear aligners compared to other orthodontic treatment modalities, and it remains up to the practitioner's assessment to select the appropriate treatment on a case by case basis.

Cytotoxic and Genotoxic effect on the Buccal Mucosa Cells of Patients Undergoing Fixed Orthodontic Treatment

AIM

To evaluate the presence of metal ions and deoxyribonucleic acid damage on the cells of buccal mucosa in subjects scheduled to undergo fixed orthodontic treatment.

MATERIALS AND METHODS

Eighty patients scheduled to undergo orthodontic treatment were included in the present study. Samples were collected from buccal mucosa of the subjects at five different intervals: before the starting of the fixed appliance therapy, 5 months after the insertion of the appliance, 10 months after insertion of the appliance, 15 months after insertion of the appliance and 20 months after insertion of the appliance. Flow cytometry was further used for assessment of apoptosis. Comet assay was used for evaluating the metal ions associated deoxyribonucleic acid ((DNA) damage of buccal epithelial cells. Atomic absorption spectrometry was used for measuring the nickel (Ni), chromium (Cr) and zinc (Zn) levels in the cells of the buccal mucosa. Analysis of data was done by SPSS software version 16.0.

RESULTS

A significant increase in the Ni, Cr and Zn concentra -tion during orthodontic treatment was observed. A progressive non-significant decrease in the percentage of viable cells from a baseline value to the end of the treatment was observed. A significant increase in the head diameter, DNA in tail and tail length, starting from the pretreatment value to the end of orthodontic treatment, was also observed.

CONCLUSION

Timely checking of deoxyribonucleic acid (DNA) damage and nuclear changes should be done for detecting earlier adverse changes.

CLINICAL SIGNIFICANCE

In patients wearing orthodontic appliances, no clinical impact occurs by wearing fixed appliances.

Salivary levels of cariogenic bacterial species during orthodontic treatment with thermoplastic aligners or fixed appliances: a prospective cohort study

BACKGROUND

Fixed orthodontic appliances might be associated with intraoral adverse effects on enamel, due to plaque accumulation and their colonization by oral microbes. At the same time, the demand for esthetic alternatives to orthodontic treatment, like thermoplastic aligners, is growing. However, thermoplastic aligners may behave differently intraorally than fixed appliances in terms of bacterial colonization and biofilm formation. Therefore, the aim of this prospective cohort study was to assess the salivary prevalence of the cariogenic bacteria Streptococcus mutans, Lactobacillus acidophilus, and Streptococcus sanguinis among adolescents treated orthodontically with thermoplastic aligners or fixed appliances.

METHODS

Thirty adolescent patients (17 girls/13 boys; mean age 13.8 years old) were assigned to treatment with either (i) self-ligating fixed appliances with nickel-titanium archwires or (ii) aligners constructed from clear transparent polyethylenterephthalat-glycol copolyester (PET-G) thermoplastic sheets. Whole stimulated saliva was collected from each patient at three time points: at baseline (before bonding and initiation of orthodontic therapy or before insertion of the thermoplastic aligners), after 2 weeks, and after 1 month. A simplified plaque index, a simplified gingival index, and the decayed, missing, and filled teeth (DMFT) index were assessed from the clinical examination of the patients. Microbiological analysis of salivary bacteria was performed by quantitative polymerase chain reaction, followed by descriptive and inferential statistics at the 5% level.

RESULTS

Although patients treated with aligners had significantly lower plaque and gingivitis scores throughout treatment compared to patients treated with fixed appliances, no significant difference could be found between the S. mutans counts of the two groups at any time through treatment (P > 0.05). On the other hand, patients treated with aligners had significantly lower salivary S. sanguinis counts at all time points than patients treated with fixed appliances (P < 0.05). Finally, almost no L. acidophilus were identified in the collected saliva samples in either of the treated samples.

CONCLUSIONS

Within the limitations of this study, there were no differences in the salivary counts of S. mutans or L. acidophilus among adolescent patients treated for 1 month with thermoplastic aligners or self-ligating appliances. On the other hand, patients treated with aligners had lower salivary levels of S. sanguinis compared to those treated with self-ligating appliances.

Effect of fixed orthodontic appliances on nonmicrobial salivary parameters

OBJECTIVES:

To examine possible changes in the levels of salivary antioxidants, C-reactive protein (CRP), cortisol, pH, proteins, and blood in patients treated with fixed orthodontic appliances.

MATERIALS AND METHODS:

Salivary samples from 21 orthodontic patients who met specific inclusion criteria were collected before the beginning of orthodontic treatment (T0; baseline), 1 hour after bonding (T1), and 4-6 weeks after bonding (T2). Oxidant-scavenging ability (OSA) was quantified using a luminol-dependent chemiluminescence assay. Cortisol and CRP levels were measured using immunoassay kits. pH levels and presence of proteins and blood in the samples were quantified using strip-based tests.

RESULTS:

A significant decrease in salivary pH was observed after bonding ( P = .013). An increase in oxidant-scavenging abilities during orthodontic treatment was detected, but the change was not statistically significant. Cortisol and CRP levels slightly increased after bonding, but the difference was small without statistical significance. Changes in the presence of proteins and blood were also insignificant.

CONCLUSIONS:

Exposure to fixed orthodontic appliances did not show a significant effect on salivary parameters related to inflammation or stress, with the exception of a significant but transient pH decrease after bonding.

Genotoxic and cytotoxic effects of Haas appliance in exfoliated buccal mucosa cells during orthodontic treatment

OBJECTIVES

To evaluate the genotoxic and cytotoxic effects of Haas appliances through micronuclei test and cytogenetic damage analysis in buccal mucosa epithelial cells of patients undergoing orthodontic treatment.

MATERIALS AND METHODS

Twenty-eight patients, 6-12 years of age and of both genders, who required a Haas appliance for the correction of a posterior crossbite were included. Epithelial cells from the mucosa were collected by gently scraping the inside of both the right and left cheeks. The cells were collected before the insertion of the appliance (T0), 1 month after the device was installed (T1), and again 3 months after the appliance was immobilized (T2). The cells were processed to obtain slides. Feulgen/Fast Green was used as the staining method, and the number of normal, karyolytic, pyknotic, nuclear buds, bi/trinucleated, and micronucleus cells were counted under light microscopy. Cellular abnormalities were evaluated with parametric and nonparametric tests for comparison of the means by analysis of variance testing, Tukey posttest, or the Kruskal-Wallis test and then by Dunn's posttest. The significance level was 5%.

RESULTS

There were no statistically significant changes in the micronuclei in the evaluated periods ( P > .05). Nuclear buds increased at T1 ( P < .05), returning to baseline levels at T2. Other abnormalities (cariolytic, pyknotic, and bi/trinucleated cells) showed a significant increase at T1 and T2 ( P < .0001).

CONCLUSIONS

The Haas appliance did not cause an increase in micronuclei in cells of the buccal mucosa. However, statistically significant increases in cariolytic, pyknotic, and bi/trinucleated cells were observed during treatment, suggesting possible DNA damage.

Comparative evaluation of treatment effects between two fixed functional appliances for correction of Class II malocclusion: A single-center, randomized controlled trial

OBJECTIVE

The objective of this study was to evaluate and compare the effects of PowerScope and Forsus in the treatment of Class II division 1 malocclusion.

MATERIALS AND METHODS

This was a 2-arm parallel, double-blind, randomized, controlled trial. A total of 28 Class II division 1 malocclusion patients indicated for treatment with fixed functional appliances were randomized and equally divided (n = 14) among PowerScope (American Orthodontics, Sheboygan, Wis; mean age 14.11 ± 1.3 years) and Forsus (3M Unitek Corp, Monrovia, Calif; mean age 15.5 ± 1.1 years) groups. Skeletal and dentoalveolar effects of PowerScope and Forsus were compared. The secondary outcomes were evaluation of patient comfort and operator convenience. Randomization was accomplished with a 1:1 allocation ratio, and concealment was achieved by sealed opaque envelopes. The participants and data collectors were all blinded to study group allocation. Data were analyzed for 26 patients, 13 in each group, as one patient from each group discontinued treatment. Statistical comparisons were carried out using Student's t-tests and chi square tests ( P ≤ .05).

RESULTS

A significantly greater mesial mandibular movement and improvement in sagittal skeletal relation were found in the Forsus patients ( P ≤ .05). The forward movement of the mandibular molar and incisors were greater in the PowerScope patients (2.3 mm and 2.80 mm) than in the Forsus patients (1.9 mm and 2.38 mm).

CONCLUSIONS

Both PowerScope and Forsus are effective in correcting Class II malocclusion. The percentage of dentoalveolar effects in correcting Class II malocclusion is more for PowerScope when compared with Forsus. Patient comfort was the same with both appliances. This trial was registered.

Pain experience in adults undergoing treatment: A longitudinal evaluation

OBJECTIVES

To quantify the intensity and duration of pain experience in adults over the initial three visits of fixed appliance-based orthodontic treatment. A secondary objective was to assess the relationship between pain experience and analgesic use, dental irregularity, gender, and age.

MATERIALS AND METHODS

A prospective longitudinal study design was adopted. Fifty-eight adults undergoing fixed appliance treatment in five orthodontic practices recorded pain experience at four time points (4 hours, 24 hours, 3 days, and 7 days) following the initial bond-up appointment (T0) and first (T1) and second (T2) routine follow-up adjustment appointments using a visual analogue scale. In addition, subjects recorded the dosage and frequency of analgesic use.

RESULTS

A slightly greater proportion of women (57%) were recruited, with a mean sample age of 34.69 (SD 12.11) years. Peak pain was experienced between 24 hours and 3 days following appliance placement (T0) and subsequent adjustments (T1 and T2). The highest mean pain score arose at T0 followed by T2 and T1 adjustments, with the difference between pain levels at these appointment intervals being statistically significant ( P < .001). The use of analgesics following each appointment mirrored pain experience, with pain score, appointment, and time point all being significant predictors of analgesic consumption. The level of dental irregularity, gender, or age did not predict pain levels reported.

CONCLUSIONS

Adults undergoing fixed orthodontic therapy should be advised that they are most likely to experience increased levels of pain for 1 to 3 days following placement of their appliance and subsequent adjustment visits.

Short-term in vivo evaluation of cellular DNA damage induced by fixed orthodontic appliances

Metal ions accumulate inside the epithelial cells of the oral mucosa and damage the DNA. The aim of this study was to analyze whether DNA damage and/or apoptosis also occurs after a short-term exposure to the metals of fixed orthodontic appliances. 23 subjects were enrolled in the test group and 8 patients in the control group. Analyses performed on samples of oral mucosa were cell count, cellular viability, quantification of intracellular metal concentration, comet and micronuclei tests and quantification of intracellular Glutathione (GSH). The obtained results indicated that orthodontic appliances release metal ions, especially chromium, that cause inflammatory processes leading to DNA damages. These phenomenon are visible only after 30 days from application of fixed orthodontic appliances.

Quantitative comparison of incisal tooth wear in patients receiving one-phase or two-phase treatment for skeletal Class III malocclusion with anterior crossbite

OBJECTIVES

The present study aimed to compare the amount of incisal tooth wear in the maxillary central incisors of patients with skeletal Class III malocclusion and anterior crossbite receiving one-phase or two-phase treatment. The hypothesis was that tooth wear would differ according to treatment modalities.

MATERIALS AND METHODS

Maxillary dental casts obtained before (T1) and after (T2) orthodontic treatment were divided into three groups. Group I consisted of casts from 21 patients (7 males, 14 females; mean age 9.8 years) who received two-phase treatment (maxillary protraction followed by fixed appliance therapy). Group II comprised casts from 37 patients who underwent orthodontic camouflage treatment for crossbite, subdivided according to age. Group IIa consisted of casts from 15 adolescents (8 males, 7 females; mean age 13.5 years), and group IIb consisted of casts from 22 adults (13 males, 9 females; mean age 24.5 years). Maxillary dental casts obtained at T1 and T2 were scanned. For each pair of digital images, T2 was superimposed on T1 using the best-fit method. Tooth wear was quantified and compared among groups.

RESULTS

Significantly less tooth wear was observed in group I compared to groups IIa and IIb, but no difference was found between groups IIa and IIb. Spearman correlation analysis revealed no significant correlation between tooth wear and age, treatment duration, or craniofacial morphology.

CONCLUSIONS

Despite the long duration of early treatment, it caused less wear of the maxillary central incisors than did orthodontic camouflage treatment.