Comparative assessment of treatment efficacy and adverse effects during nonextraction orthodontic treatment of Class I malocclusion patients with direct and indirect bonding: A parallel randomized clinical trial

Evaluation of the accuracy of digital indirect bonding vs. conventional systems: a randomized clinical trial

OBJECTIVES

To compare the accuracy and chair time of self-ligating brackets using direct bonding, traditional indirect bonding (IB), and computer-aided design/computer-aided manufacturing (CAD/CAM) IB techniques after orthodontic leveling and alignment.

MATERIALS AND METHODS

Forty-five patients were randomly assigned to three bonding groups (G1 [n = 15], G2 [n = 15], and G3 [n = 15]). Evaluation after the alignment and leveling phases used two parameters of the objective grading system of the American Board of Orthodontics for root parallelism and posterior marginal ridges, assessed using panoramic radiographies (PR I and PR II), a digital model, and a plaster model. Blinding was only applied for outcome assessment. No serious harm was observed except for gingivitis associated with plaque accumulation.

RESULTS

Although G3 showed better numerical results, they were not statistically significant in the radiographic or model evaluations (P > .001). Mean chair time was significantly shorter in G3 (1.1 ± 11.8 min) vs. G1 (56.7 ± 7.3 min) and G2 (52.8 ± 8.3 min; P < .001).

CONCLUSIONS

The CAD/CAM IB system for self-ligating brackets was as effective as conventional methods, with a shorter chair time.

Occlusal outcome of orthodontic treatment: a systematic review with meta-analyses of randomized trials

BACKGROUND

Several appliances or treatment protocols are marketed to either patients or orthodontists as being associated with improved orthodontic outcomes. However, clinical decision-making should be based on robust scientific evidence and not marketing claims or anecdotal evidence.

OBJECTIVE

To identify appliances/protocols being associated with improved outcomes of fixed appliance treatment.

SEARCH METHODS

Unrestricted literature searches in seven databases/registers for human studies until March 2024.

SELECTION CRITERIA

Randomized or quasi-randomized clinical trials on human patients of any age, sex, or ethnicity receiving comprehensive orthodontic treatment with fixed appliances and assessing occlusal outcome with either the Peer Assessment Rating (PAR) or the American Board of Orthodontics-Objective Grading System (ABO-OGS) index.

DATA COLLECTION AND ANALYSIS

Duplicate/independent study selection, data extraction, and risk of bias assessment with the Cochrane RoB 2 tool. Random-effects meta-analyses of averages or mean differences with their 95% Confidence Intervals (CI), followed by meta-regression/subgroup/sensitivity analyses and assessment of the quality of clinical recommendations with the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

Data from 20 small- to moderately-sized trials covering 1470 patients indicated that orthodontic treatment with fixed appliances is effective and results on average in a final PAR score of 6.0 points (95% CI 3.9-8.2 points), an absolute PAR reduction of 23.0 points (95% CI 15.6-30.4 points), a % PAR reduction of 82.6% (95% CI 70.8%-94.4%), and an absolute ABO-OGS score of 18.9 points (95% CI 11.7-26.2 points). However, very high between-study heterogeneity (I2 > 75%) was seen for both PAR and ABO-OGS. Extraction treatment was associated with significantly better occlusal outcome than non-extraction treatment with ABO-OGS (12.9 versus 16.6 points; P = .02). There was no statistically significant difference in occlusal outcome with (i) 0.018″-slot or 0.022″-slot brackets; (ii) customized or prefabricated brackets; (iii) anchorage reinforcement with temporary anchorage devices; (iv) use of vibrational adjuncts; and (v) aligners or fixed appliances (P > .05 in all instances), while small benefits were seen with indirectly bonded brackets.

CONCLUSIONS

Considerable between-study heterogeneity exists in the reported occlusal outcome of fixed appliance treatment, and different appliances or adjuncts have little effect on this. Standardization and/or automatization of the scoring procedures for PAR and ABO-OGS might help to improve consistency and reliability of outcome measurement in orthodontic trials.

REGISTRATION

PROSPERO (CRD42024525088).

Comprehensive clinical evaluation of indirect and direct bonding techniques in orthodontic treatment: a single-centre, open-label, quasi-randomized controlled clinical trial

BACKGROUND

Few prospective investigations have compared direct and indirect techniques through comprehensive and detailed clinical evaluations, considering the impact of all factors.

OBJECTIVES

This study aimed to compare and evaluate direct and indirect bonding methods at a single institution and to clarify the selection criteria for the bonding method.

MATERIALS AND METHODS

This single-centre, quasi-randomized controlled clinical trial included 153 patients who required fixed orthodontic treatment. They were randomly divided into indirect and direct binding groups by the project lead (K.K.), who was blinded to all clinical data, and performed the allocation using medical record numbers. The chair time for bracket bonding, discomfort during bracket bonding, oral hygiene after bonding, number of bracket failures, number of intentional bracket reattachments, post-treatment occlusal index, and total treatment time were assessed. Outcomes were compared using a two-sample t-test or Mann-Whitney U test (P < .05).

RESULTS

Fifty-eight patients were included in the indirect bonding group (20 male, 38 female; mean age: 20.63 ± 5.69 years) and 66 (14 male, 52 female; mean age: 23.17 ± 8.83 years) in the direct bonding group. Compared to the direct bonding group, the indirect bonding group had shorter chair time (P < .001), a shorter total treatment period (P < .01), and a better final occlusal relationship (P < .001). The number of bracket detachments was higher (P < .001) in the indirect bonding group, but the number of intentional reattachments was lower (P < .001).

CONCLUSION

Indirect bonding may improve the efficiency of orthodontic treatment.

HARMS

No harm was observed during the study.

TRIAL REGISTRATION NUMBER

This trial was approved by the Ethics Review Committee of Okayama University (approval number: d10001), UMIN registration number 000022182.

Comparison of enamel demineralization and periodontal status between direct and digital indirect bonding techniques : A split-mouth clinical trial of direct vs. digital indirect bonding

OBJECTIVES

This randomized clinical trial aimed to evaluate the effects of digital indirect bonding (DIB) compared to the direct bonding (DB) technique in terms of enamel demineralization and periodontal status.

MATERIALS AND METHODS

A total of 24 patients (17 females, 7 males) with a mean age of 13.83 ± 1.55 years were bonded using DB and DIB techniques using a split-mouth study design. Bonding techniques were randomly allocated to quadrants. Demineralization measurements were performed with the DIAGNOdent pen (Kavo, Biberach, Germany) from four sides (distal, gingival, mesial, and incisal/occlusal) of all brackets immediately after bonding, 1 month (T1), and 6 months (T2) after bonding. Periodontal measurements were taken before bonding and at the same time points (T1 and T2). Data were statistically analyzed with the Mann-Whitney U test to determine possible differences between groups.

RESULTS

Incisal/occlusal sides exhibited the lowest demineralization values at T2. The gingival side of upper centrals, mesial side of upper laterals, and distal sides of upper first premolar and lower laterals brackets bonded with the DIB technique exhibited significantly increased demineralization compared with the DB technique from T0 to T2 (p < 0.05). Periodontal parameters increased 1 month after bonding and decreased during the follow-up. Bonding technique showed no statistically significant difference in plaque index, gingival index, and bleeding on probing values at any time interval.

CONCLUSION

There were many locations around the brackets with significantly higher demineralization after 6 months in patients who received digital indirect bonding compared to the DB group. Although periodontal health was generally adequate, complete removal of adhesive flash should be carefully carried out to decrease the risk of demineralization during indirect bonding technique with digital workflows.

Accuracy of One-Piece vs. Segmented Three-Dimensional Printed Transfer Trays for Indirect Bracket Placement

OBJECTIVE

To assess the accuracy of three-dimensional (3D) printed one-piece vs. multiple segmented transfer trays for indirect bonding techniques in moderate and severe crowding cases.

METHODS

Eighty digital maxillary dental models were produced by an extraoral scanner. 3D-printed one-piece and segmented trays were virtually designed utilizing Maestro 3D Ortho Studio® v4 and printed using a NextDent printer. The sample was classified into two groups: Group 1 (moderate crowding) included 40 digital models with a space deficiency of 6-7 mm, and Group 2 (severe crowding) included 40 digital models with a space deficiency of 10 mm. Ortho classic brackets were then placed into the 3D printed models with the aid of the transfer trays, and the models with the final bracket positioning were scanned using iTero scanner. Four measurements were selected on each tooth to perform the analysis. Mann-Whitney and Kruskal-Wallis tests were used for comparisons. A p-value of ≤ 0.05 was considered statistically significant.

RESULTS

In the moderate crowding group, statistically significant differences were detected between the one-piece, segmented, and control groups for three measurements (p < 0.001), while the rest of the measurements showed no significant differences (p > 0.05). In the severe crowding group, no significant differences were detected for any of the measurements.

CONCLUSIONS

One-piece and segmented 3D-printed transfer trays are considered accurate tools for indirect bonding in moderate and severe malocclusion cases. The severity of crowding did not affect the accuracy of bracket transfer in indirect bonding.

Is bracket bonding with guided bonding devices accurate enough for crowded dentition?

BACKGROUND

This research aimed to study whether bracket bonding using guided bonding devices (GBDs) is accurate enough for crowded dentitions in vitro.

METHODS

Fifteen three-dimensionally (3D) printed resin model sets were included and divided into three groups: mild, moderate, and severe crowding. The resin models were scanned and virtually bonded with brackets. Corresponding GBDs were generated and 3D printed. Subsequently, the brackets were bonded to the resin models on a dental mannequin using the GBDs. The models with bonded brackets were scanned, and comparisons were made between the positions of the actually bonded and the planned ones to evaluate possible deviations.

RESULTS

There was no immediate bonding failure in any group. The bonding duration tended to increase with crowding severity (P > 0.05). Almost all linear and angular deviations in all groups were below 0.5 mm and 2°, respectively, and no statistically significant difference was found among the different crowding degrees (P > 0.05). In all groups, the brackets tended to deviate lingually and had buccal crown torque. Brackets in the groups with mild and severe crowding showed a tendency for mesiobuccal rotation.

CONCLUSION

GBDs provide high bracket bonding accuracy for dentitions with different crowding degrees and, thus, could hopefully be applied to uncrowded and crowded dentitions alike.

Influence of the design of 3D-printed indirect bonding trays and experience of the clinician on the accuracy of bracket placement

PURPOSE

The aim was to investigate the influence of three different three-dimensional (3D)-printed bonding tray designs and professional experience on accuracy of indirect bracket placement.

METHODS

Virtual bracket placement was performed on a scanned dental model using OnyxCeph software (Image Instruments, Chemnitz, Germany). Three different designs for indirect bonding trays (open, semi-open, and closed design) were created and produced using a 3D printer. To analyze the influence of professional experience, one of the three tray designs was produced twice. In this case, bracket placement was performed by an inexperienced dentist. Bracket positions were scanned after the indirect bonding procedure. Linear and angular transfer errors were measured. Significant differences between the target and actual situation were analyzed using the Kruskal-Wallis and χ2 test.

RESULTS

All bonding tray designs resulted in comparable results. The results of the unexperienced dentist showed significantly higher deviations than those for the experienced orthodontist in the torque direction. However, the mean values were comparable. The open tray design exceeded the clinically acceptable limits of 0.25 mm and 1° more often. The inexperienced dentist exceeded these limits significantly more often than the experienced orthodontist in the vertical and torque direction. The immediate bracket loss rate showed no significant differences between the different tray designs. Significantly more bracket losses were observed for the inexperienced dentist during the procedure compared to the experienced orthodontist.

CONCLUSIONS

The bonding tray design and professional experience had an influence on the exceedance of clinically relevant limits of positioning accuracy and on the bracket loss rate.

Evaluation of effectiveness and efficiency of fixed orthodontic treatment comparing standard and computer-aided design and manufacturing conventional bracket systems using indirect bonding for both: A retrospective study

BACKGROUND

To compare the effectiveness and efficiency of orthodontic treatment (OT) with standard versus computer-aided design and computer-aided manufacturing (CAD/CAM) indirect bonding of conventional brackets.

METHODS

This retrospective study examined two groups: standard indirect bonding group (12 males, 13 females; mean age 12.21 ± 0.52 years), and digital indirect bonding group (11 males, 14 females; mean age 12.76 ± 1.32 years), treated via a CAD/CAM indirect bonding system. Conventional brackets were used in both groups. Pretreatment and post-treatment records were acquired for all subjects. Weighted Peer Assessment Rating (W-PAR) index was used to assess the effectiveness of OT, in conjunction with five angular cephalometric measurements (ANB°, Sn-GoGn°, U1-PP°, IMPA° and FMA°) and comparatively analyzed using generalized mixed-effects models and post hoc test. Treatment efficiency was assessed in terms of the numbers of bracket repositionings, archwire bends, accidental bracket debondings, appointments and treatment months. Comparative analysis of efficiency was performed using the asymptotic Wilcoxon-Mann-Witney test. Statistical significance was set at 5%.

RESULTS

Total W-PAR and W-PAR component scores decreased significantly during treatment for both groups and in a similar way. Cephalometric measures ANB° and IMPA° significantly decreased and increased, respectively. Significantly fewer bracket repositionings, number of appointments and treatment months were recorded in group digital indirect bonding.

CONCLUSIONS

Although both methods investigated were effective to achieve good outcomes, CAD/CAM indirect bonding method increased the efficiency of OT, when conventional brackets are used.

Accuracy of 3-dimensional-printed customized transfer tray using a flash-free adhesive system in digital indirect bonding: An in vivo study

INTRODUCTION

This paper evaluated the accuracy of a computer-aided design and manufacturing indirect bonding technique using a new customized 3D-printed transfer tray and a flash-free adhesive system for orthodontic bonding.

METHODS

This in vivo study analyzed 106 teeth selected from 9 patients undergoing orthodontic treatment. Quantitative deviation analysis was performed to evaluate the bonding positioning errors, assessing the differences between the virtually planned and the clinically transferred bracket position after indirect bonding procedures by superimposing 3-dimensional dental scans. Estimated marginal means were evaluated for individual brackets and tubes, arch sectors, and overall collected measurements.

RESULTS

A total of 86 brackets and 20 buccal tubes were analyzed. Among individual teeth, mandibular second molars showed the highest positioning errors, whereas maxillary incisors reported the lowest values. Considering arch sectors, the posterior areas showed greater displacements than the anterior areas, as the right side compared to the left side, with a higher error rate reported for the mandibular arch than the maxillary arch. The overall bonding inaccuracy measurement was 0.35 mm, below the clinical acceptability limit of 0.50 mm.

CONCLUSIONS

The accuracy of a 3-dimensional-printed customized transfer tray using a flash-free adhesive system in computer-aided design and manufacturing indirect bonding was generally high, with greater positioning errors for posterior teeth.

White Spot Lesions (WSLs)-Post-Orthodontic Occurrence, Management and Treatment Alternatives: A Narrative Review

Although treatment with fixed or mobile appliances has become an important part of modern orthodontics, side effects such as white spot lesions (WSLs) have a negative impact on the aesthetic outcome of orthodontic treatment. The purpose of this article was to review current evidence on the diagnosis, risk assessment, prevention, management and post-orthodontic treatment of these lesions. Data collection was performed electronically, and the initial search using the keywords "white spot lesions", "orthodontics", "WSL", "enamel" and "demineralization" in different combinations resulted in 1032 articles for the two electronic databases used. Ultimately, a total of 47 manuscripts were considered relevant to the aim of this research and included in this review. The results of the review indicate that WSLs remain a significant problem during orthodontic treatment. According to studies in the literature, the severity of WSLs correlates to the duration of treatment. Using toothpaste with more than 1000 ppm fluoride at home reduces the frequency of WSL separation and regular application of varnishes in the office reduces the frequency of the occurrence of WSLs only in the context of maintaining a strict hygiene regime. The old hypothesis that elastomeric ligatures retain more dental plaque than metal ones has been refuted. There are no differences in the appearance of WSLs between conventional brackets and self-ligating brackets. Clear aligner mobile devices develop fewer WSLs but are more extensive as opposed to conventional fixed devices, while lingual orthodontic appliances have a lower incidence of WSLs, and the most effective device for preventing these lesions is WIN, followed by Incognito.

Accuracy of indirect bracket placement with medium-soft, transparent, broad-coverage transfer trays fabricated using computer-aided design and manufacturing: An in-vivo study

INTRODUCTION

The objective of this study was to test the precision of in-vivo indirect bracket placement via medium-soft, transparent, broad-coverage, computer-aided designed and manufactured transfer trays using an automated digital method.

METHODS

Seventeen patients requiring vestibular fixed appliances were consecutively recruited, and bonding accuracy was measured at each bracket, evaluating 3 linear (mesiodistal, buccolingual, and vertical) and 3 angular measurements (torque, tip, and rotation) with an automated method involving digital superimposition of individual teeth. Mean and standard deviation values were calculated for both arches, single arch, and tooth type, and the percentages of single deviations over the thresholds of 0.25 mm and 1° were calculated, as well as maximum and minimum values for each deviation and directional bias. Correlations between each variable (arch, tooth type, and single tooth) and deviations were investigated through classification and regression trees (CART) predictive models.

RESULTS

Neither mean nor single linear deviations ever exceeded the set cutoff value of 0.25 mm. Mean angular deviations never exceeded 1°, but some individual angular deviations did, specifically 8.31% of torque, 13.16% of tip, and 7.16% of rotation deviations. The highest percentage of deviation was recorded for rotation of the maxillary incisors (18.11%). No evident trend in directional deviation bias was found. Tooth type appears to influence mesiodistal and torque deviations, whereas the single tooth variable influenced the percentage of rotation deviations exceeding 1° (P <0.05).

CONCLUSIONS

This computer-aided designed and manufactured medium-soft, transparent transfer tray provides accurate bracket placement and could be recommended for routine fixed appliance treatment.

Accuracy of 3-dimensional printed bracket transfer tray using an in-office indirect bonding system

INTRODUCTION

In this study, we aimed to evaluate and compare the bracket positioning accuracy of the indirect bonding (IDB) transfer tray fabricated in-clinic using the tray printing (TP) and marker-model printing methods (MP).

METHODS

The TP group was further divided into 2 groups (single-tray printing [STP] and multiple-tray printing [MTP]) depending on the presence of a tray split created using the 3-dimensional (3D) software. Five duplicated plaster models were used for each of the 3 experimental groups, and a total of 180 artificial teeth, except the second molar, were evaluated in the experiment. The dental model was scanned using a model scanner (E3; 3Shape Dental Systems, Copenhagen, Denmark). Virtual brackets were placed on facial axis points, and the IDB trays were designed and fabricated using a 3D printer (VIDA; EnvisionTEC, Mich). The accuracy of bracket positioning was evaluated by comparing the planned bracket positions and the actual bracket positions using 3D analysis on inspection software. The main effects and first-order interaction effects were analyzed together by analysis for the analysis of variance.

RESULTS

The mean distance and height errors were significantly lower in the STP group than those in the MP and MTP groups (P <0.05). The mean distance error was 0.06 mm in the STP group and 0.09 mm in the MP and MTP groups. The mean height error was 0.10 mm in the STP group and 0.15 mm and 0.18 mm in MP and MTP groups, respectively. However, no significant differences were observed in the angular errors among the 3 groups.

CONCLUSIONS

The in-office-fabricated IDB system with computer-aided design and 3D printer is clinically applicable after considering the linear and angular errors. We recommend IDB trays fabricated using the STP method owing to the lower frequency of bracket positioning errors and ease of fabrication.

For Indirect Orthodontic Attachment Placement, Adding a Custom Composite Resin Base Is Not Beneficial: A Split-Mouth Randomized Clinical Trial

Aim

The aim of this study was to compare the chairside time, bond failure rate, and accuracy of bonding between two orthodontic attachment indirect bonding techniques.

Methods and Materials

Two indirect bonding techniques were studied: unaltered base attachment (UA) and custom base attachment (CBA) methods. Eighty-four orthodontic attachments were bonded on six patient stone models. Preoperative models were digitally scanned, and subsequently, attachments were transferred with the aid of a single but sectioned vacuum-formed tray to their corresponding patients. Finally, participants were scanned after attachment bonding to make the postoperative digital replicas. Chairside time and immediate bond failure rates were measured and compared between both techniques. Postoperative and preoperative digital models were then superimposed in order to measure the accuracy of bonding in the three dimensions of space.

Results

No differences existed between the two techniques regarding chairside time (P=0.87) and bond failure rates (P=0.37). There were also no differences found for the total attachment movement (P=0.73), mesiodistal (P=0.10), occlusogingival (P=0.31), torquing (P=0.21), and rotational measurements (P=0.18). The UA technique, however, proved to be more accurate for buccopalatal linear directions (P=0.04), whilst the CBA technique showed more accuracy for tipping angular deviations (P < 0.01). There was a statistically significant directional bias for the UA towards the occlusal (P < 0.01) and palatal (P=0.02) directions with mesial-out angular deviation (P=0.02).

Conclusion

The two indirect bonding techniques were comparable for chairside time, bond failure rates, and most linear and angular measurements. The UA technique was, however, superior in buccopalatal directions, while the CBA method showed more tipping accuracy. Both techniques were efficient and reliable for indirect bonding.

Bracket Transfer Accuracy with the Indirect Bonding Technique-A Systematic Review and Meta-Analysis

Purpose: To investigate the bracket transfer accuracy of the indirect bonding technique (IDB). Methods: Systematic search of the literature was conducted in PubMed MEDLINE, Web of Science, Embase, and Scopus through November 2021. Selection Criteria: In vivo and ex vivo studies investigating bracket transfer accuracy by comparing the planned and achieved bracket positions using the IDB technique were considered. Information concerning patients, samples, and applied methodology was collected. Measured mean transfer errors (MTE) for angular and linear directions were extracted. Risk of bias (RoB) in the studies was assessed using a tailored RoB tool. Meta-analysis of ex vivo studies was performed for overall linear and angular bracket transfer accuracy and for subgroup analyses by type of tray, tooth groups, jaw-related, side-related, and by assessment method. Results: A total of 16 studies met the eligibility criteria for this systematic review. The overall linear mean transfer errors (MTE) in mesiodistal, vertical and buccolingual direction were 0.08 mm (95% CI 0.05; 0.10), 0.09 mm (0.06; 0.11), 0.14 mm (0.10; 0.17), respectively. The overall angular mean transfer errors (MTE) regarding angulation, rotation, torque were 1.13° (0.75; 1.52), 0.93° (0.49; 1.37), and 1.11° (0.68; 1.53), respectively. Silicone trays showed the highest accuracy, followed by vacuum-formed trays and 3D printed trays. Subgroup analyses between tooth groups, right and left sides, and upper and lower jaw showed minor differences. Conclusions and implications: The overall accuracy of the indirect bonding technique can be considered clinically acceptable. Future studies should address the validation of the accuracy assessment methods used.

An Updated Review of the Efficacy and Safety of Direct Oral Anticoagulants in Treatment of Left Ventricular Thrombus

Left ventricular (LV) thrombus is a potentially serious complication affecting males and females with ischemic and nonischemic cardiomyopathy-specifically, after acute myocardial infarctions of the anterior left ventricular wall and long-standing tachyarrhythmias, respectively. LV thrombi pose significant risks for systemic embolization and devastating stroke events, while also demanding a treatment carrying inherent risks of its own. It is therefore imperative to have accurate detection of these ventricular thrombi and an appropriate understanding of the risks and benefits regarding management. Anticoagulation using warfarin has long been established as the gold-standard level of care in the current guidelines of the American College of Cardiology but the advent of direct oral anticoagulants (DOACs) prompts a re-examination of the literature. The particular question we seek to answer lies in the efficacy of these drugs and the safety and outcomes when used to treat LV thrombi. Recent case reports, meta-analyses, and most recently, the breakthrough of 2 novel randomized controlled trials have shown DOACs to be a promising treatment for LV thrombus. Contrarily, some retrospective cohort reviews suggest less-than-promising outcomes. This meta-analysis hopes to provide a current, curated review of up-to-date safety and efficacy in the documented tales of DOACs and LV thrombi that has been published since early 2020-by selecting these curated case studies, and analyzing the most recent randomized controlled trials, we hope to engage the reader with clearer illustrations of the key components of both the advocacy and warning of this pharmaceutical intervention.

Orthodontic treatment for crowded teeth in children

BACKGROUND

Crowded teeth develop when there is not enough space in the jaws into which the teeth can erupt. Crowding can affect baby teeth (deciduous dentititon), adult teeth (permanent dentition), or both, and is a common reason for referral to an orthodontist. Crowded teeth can affect a child's self-esteem and quality of life. Early loss of baby teeth as a result of tooth decay or trauma, can lead to crowded permanent teeth. Crowding tends to increase with age, especially in the lower jaw.

OBJECTIVES

To assess the effects of orthodontic intervention for preventing or correcting crowded teeth in children. To test the null hypothesis that there are no differences in outcomes between different orthodontic interventions for preventing or correcting crowded teeth in children.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched four bibliographic databases up to 11 January 2021 and used additional search methods to identify published, unpublished and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated any active interventions to prevent or correct dental crowding in children and adolescents, such as orthodontic braces or extractions, compared to no or delayed treatment, placebo treatment or another active intervention. The studies had to include at least 80% of participants aged 16 years and under.

DATA COLLECTION AND ANALYSIS

Two review authors, independently and in duplicate, extracted information regarding methods, participants, interventions, outcomes, harms and results. We resolved any disagreements by liaising with a third review author. We used the Cochrane risk of bias tool to assess the risk of bias in the studies. We calculated mean differences (MDs) with 95% confidence intervals (CI) for continuous data and odds ratios (ORs) with 95% CIs for dichotomous data. We undertook meta-analysis when studies of similar comparisons reported comparable outcome measures, using the random-effects model. We used the I2 statistic as a measure of statistical heterogeneity.

MAIN RESULTS

Our search identified 24 RCTs that included 1512 participants, 1314 of whom were included in analyses. We assessed 23 studies as being at high risk of bias and one as unclear.  The studies investigated 17 comparisons. Twenty studies evaluated fixed appliances and auxiliaries (lower lingual arch, lower lip bumper, brackets, archwires, lacebacks, headgear and adjunctive vibrational appliances); two studies evaluated removable appliances and auxiliaries (Schwarz appliance, eruption guidance appliance); and two studies evaluated dental extractions (lower deciduous canines or third molars). The evidence should be interpreted cautiously as it is of very low certainty. Most interventions were evaluated by a single study. Fixed appliances and auxiliaries One study found that use of a lip bumper may reduce crowding in the early permanent dentition (MD -4.39 mm, 95% CI -5.07 to -3.71; 34 participants). One study evaluated lower lingual arch but did not measure amount of crowding. One study concluded that coaxial nickel-titanium (NiTi) archwires may cause more tooth movement in the lower arch than single-stranded NiTi archwires (MD 6.77 mm, 95% CI 5.55 to 7.99; 24 participants). Another study, comparing copper NiTi versus NiTi archwires, found NiTi to be more effective for reducing crowding (MD 0.49 mm, 95% CI 0.35 to 0.63, 66 participants). Single studies did not show evidence of one type of archwire being better than another for Titinol versus Nitinol; nickel-titanium versus stainless steel or multistrand stainless steel; and multistranded stainless steel versus stainless steel.  Nor did single studies find evidence of a difference in amount of crowding between self-ligating and conventional brackets, active and passive self-ligating brackets, lacebacks added to fixed appliances versus fixed appliances alone, or cervical pull headgear versus minor interceptive procedures. Meta-analysis of two studies showed no evidence that adding vibrational appliances to fixed appliances reduces crowding at 8 to 10 weeks (MD 0.24 mm, 95% CI -0.81 to 1.30; 119 participants). Removable appliances and auxiliaries One study found use of the Schwarz appliance may be effective at treating dental crowding in the lower arch (MD -2.14 mm, 95% CI -2.79 to -1.49; 28 participants). Another study found an eruption guidance appliance may reduce the number of children with crowded teeth after one year of treatment (OR 0.19, 95% CI 0.05 to 0.68; 46 participants); however, this may have been due to an increase in lower incisor proclination in the treated group. Whether these gains were maintained in the longer term was not assessed. Dental extractions One study found that extracting children's lower deciduous canines had more effect on crowding after one year than no treatment (MD -4.76 mm, 95 CI -6.24 to -3.28; 83 participants), but this was alongside a reduction in arch length. One study found that extracting wisdom teeth did not seem to reduce crowding any more than leaving them in the mouth (MD -0.30 mm, 95% CI -1.30 to 0.70; 77 participants).

AUTHORS' CONCLUSIONS

Most interventions were assessed by single, small studies. We found very low-certainty evidence that lip bumper, used in the mixed dentition, may be effective for preventing crowding in the early permanent dentition, and a Schwarz appliance may reduce crowding in the lower arch. We also found very low-certainty evidence that coaxial NiTi may be better at reducing crowding than single-stranded NiTi, and that NiTi may be better than copper NiTi. As the current evidence is of very low certainty, our findings may change with future research.

Occlusal outcome after orthodontic treatment with preadjusted straight-wire and standard edgewise appliances : A retrospective cohort study

PURPOSE

Orthodontic fixed appliances have been proven to be effective in treating a wide variety of malocclusions, and different types of appliances have emerged during recent decades. However, the comparative effects of different appliances have not been adequately assessed. Thus, the aim was to assess the occlusal outcome of orthodontic treatment with preadjusted straight-wire (SWIRE) and standard edgewise (SEDGE) appliances.

METHODS

In all, 56 patients (mean age: 13.5 years; 45% male) receiving extraction-based treatment with either SWIRE or SEDGE appliances were included. Between-group differences in the occlusal outcome assessed with the American Board of Orthodontists Objective Grading System (ABO-OGS) and treatment duration were analyzed statistically at the 5% level.

RESULTS

The average ABO-OGS score was 31.3 ± 7.2 points and 34.0 ± 10.4 points in the SWIRE and SEDGE groups with no statistically significant difference between groups (P = 0.26). Treatment duration was significantly shorter in the SWIRE group compared to the SEDGE group, with an average difference of -6.8 months (95% confidence interval [95% CI] = -9.6 to -4.0 months; P < 0.001). Likewise, fewer visits were needed with SWIRE compared to SEDGE appliances with an average difference of -7.2 visits (95% CI = -10.3 to -4.2 visits; P < 0.001). Adjusting for the influence of any potential confounders did not considerably impact the results.

CONCLUSION

Similar treatment outcomes were observed after premolar extraction treatment with SWIRE and SEDGE appliances. On the other hand, SEDGE appliances were associated with prolonged treatment duration and more visits needed to complete treatment compared to SWIRE appliances.

Stability of occlusal outcome during long-term retention: the time-dependent variation of the American Board of Orthodontics index

BACKGROUND

The aim of this retrospective cohort study was to assess long-term occlusal changes at debond and a median of 8 years afterwards (in retention) with the American Board of Orthodontics (ABO) objective grading system and identify risk factors.

MATERIALS AND METHOD

Fifty patients (median age: 14.3 years at debond; 60% female) treated with fixed appliances (25 with and 25 without premolar extractions) were included. The occlusal outcome was assessed with the ABO tool and analyzed statistically at 5%.

RESULTS

Extraction treatment was associated with better occlusal outcome than non-extraction treatment (34.2 versus 40.9 points; P = 0.009). In retention, ABO scores improved by 7.4 points, while patients with worse debond finishing improved more afterwards (P = 0.001). Alignment/rotations deteriorated in 58% of the cases and occlusal relationships in 38% of the cases. Marginal ridges improved more for extraction than non-extraction patients (28% versus 0%; P = 0.001). Occlusal relationships improved more for cases that 'passed' the ABO requirements at debond than failed cases (64% versus 28%; P = 0.02). Furthermore, patients with worse debond ABO scores were more likely to deteriorate at alignment/rotations in retention. Finally, the proportion of cases passing the ABO requirements improved considerably between debond (28%) and in retention (54%) as half (47%) of the cases that had failed the ABO requirements at debond passed them in retention.

CONCLUSIONS

Considerable long-term occlusal changes are seen post-debond, which mostly favour improved settling. Extraction treatment and higher finishing quality at debond significantly influenced the chance for improvement. However, setting a cut-off score to denote treatment excellence showed considerable instability through time.

A comparative assessment of transfer accuracy of two indirect bonding techniques in patients undergoing fixed mechanotherapy: A randomised clinical trial

OBJECTIVES

To assess the transfer accuracy of three-dimensional (3D) printed transfer trays and compare them with transfer trays made up of polyvinyl siloxane (PVS) for use in indirect bonding.

DESIGN

This was a two-arm parallel prospective randomised controlled trial.

SETTING

The trial was undertaken at the outpatient department of a dental college.

PARTICIPANTS

A total of 30 patients (18 men, 12 women) were randomly allocated to two groups.

METHODS

The inclusion criteria included patients with permanent and fully erupted dentition (age range = 17-24 years), Angles class I malocclusion with crowding <3 mm requiring non-extraction treatment, good oral hygiene and no previous history of orthodontic treatment. Blinding was applicable only for outcome assessment. Indirect bonding was performed by the primary investigator for both the groups. Digital images of the pre-transfer and post-transfer brackets were obtained by means of an intra-oral scanner and compared using software. Superimpositions of pre- and post-transfer images were done to determine the transfer error for linear and angular variables for all tooth types.

RESULTS

A total of 600 teeth were bonded, 300 each for both groups. Statistically significant differences were observed in all dimension between the two groups, with 3D-printed trays being more accurate than PVS trays except in the vertical dimension (P < 0.05). The prevalence of clinically unacceptable transfer errors revealed that most of the transfer errors were in the vertical dimensions for 3D-printed trays.

CONCLUSION

3D-printed trays are more accurate than PVS trays except for transfers in vertical dimension.

Reproducibility of digital indirect bonding technique using three-dimensional (3D) models and 3D-printed transfer trays

OBJECTIVE

To evaluate the reproducibility of digital tray transfer fit on digital indirect bonding by analyzing the differences in bracket positions.

MATERIALS AND METHODS

Digital indirect bonding was performed by positioning brackets on digital models superimposed by tomography using Ortho Analyzer (3Shape) software. Thirty-three orthodontists performed indirect bonding on prototyped models of the same malocclusion using prototyped transfer trays for two types of brackets (MiniSprint Roth and BioQuick self-ligating). The models with brackets were scanned using an intraoral scanner (Trios, 3Shape). Superimpositions were made between the digital models obtained after indirect bonding and those from the original virtual setup. To analyze the differences in bracket positions, three planes were examined for each bracket: vertical, horizontal, and angulation. Three orthodontists repeated indirect bonding after 15 days, and Bland-Altman plots and intraclass correlation coefficients were used to evaluate inter- and intraevaluator reproducibility and reliability, respectively. Repeated-measures analysis of variance (ANOVA) was used to analyze the differences between bracket positions, and multivariate ANOVA was used to evaluate the influence of orthodontists' experience on the results.

RESULTS

Differences between bracket positions were not statistically significant, except mesial-distal discrepancies in the BioQuick group (P = .016). However, differences were not clinically significant (horizontal varied from 0.04 to 0.13 mm; angulation, 0.45° to 2.03°). There was no significant influence of orthodontist experience and years of clinical practice on bracket positions (P = .314 and P = .158). The reproducibility among orthodontists was confirmed.

CONCLUSIONS

The reproducibility of digital indirect bonding was confirmed in terms of bracket positions using three-dimensional printed transfer trays.

A comparative assessment of orthodontic treatment outcomes using the quantitative light-induced fluorescence (QLF) method between direct bonding and indirect bonding techniques in adolescents: a single-centre, single-blind randomized controlled trial

Introduction

The aim of this two-arm parallel trial was to evaluate enamel demineralization in fixed orthodontic treatment using an indirect bonding technique in comparison to a direct bonding technique by the quantitative light-induced fluorescence (QLF) method.

Design, settings and participants

Fifty-six patients who needed fixed orthodontic treatment were randomly separated into either the direct bonding group or the indirect bonding group. The presence and extent of lesions on the buccal surfaces of all teeth, except the molar teeth, were assessed. The percentage of fluorescence loss (ΔF and ΔFmax), the degree of demineralization (ΔQ) and lesion area (WS area) were determined using the system’s software. The data were analysed with the Wilcoxon signed-rank and Mann–Whitney U-tests (P &lt; 0.05).

Interventions

Treatment with a direct bonding or an indirect bonding technique.

Results

This study was completed with 25 patients in the indirect bonding group (12 females, 13 males; mean age: 15.42 ± 1.71 years) and 26 patients in the direct bonding group (12 females, 14 males; mean age: 14.73 ± 1.65 years). In the indirect bonding technique, a few teeth (especially mandibular left canine: 50.45 ± 93.48; 95% confidence interval: −12.35 and 113.26) were found to develop significant white spot lesion (WSL) formation (P &lt; 0.05). However, the number of teeth with demineralization was higher in the direct bonding group (P &lt; 0.05).

Conclusion

The bonding procedures used in the indirect bonding technique contribute to reducing the degree of WSL formation. Further, the use of flowable composite adhesives in this bonding process is more effective at reducing the appearance of WSLs than in cases where conventional composite adhesives are used.

Limitations

The limitation of our trial may be the small sample size and the short follow-up time for the patients.

Harms

No harms were detected during the study.

Protocol

The protocol was not published before trial commencement.

Registration

This trial was registered post hoc at ‘Clinical Trials’ (http://www.clinicaltrials.gov), registration number (ID): NCT03738839.

Effectiveness, efficiency and adverse effects of using direct or indirect bonding technique in orthodontic patients: a systematic review and meta-analysis

Background

The direct and indirect bonding techniques are commonly used in orthodontic treatment. The differences of the two techniques deserve evidence-based study.

Materials and methods

Randomized controlled trials (RCTs), wherein direct and indirect bonding techniques were used in orthodontic patients were considered. The MEDLINE, EMBASE, CENTRAL and Web of Science databases were searched to identify relevant articles published up to December 2018. Grey literature was also searched. Two authors performed data extraction independently and in duplicate using the data collection form. The included trials were assessed using the Cochrane risk of bias assessment tool.

Results

Of the 1557 studies screened, 42 full articles were scrutinized and assessed for eligibility. Eight RCTs (247 participants) were finally included for the analyses. The qualitative synthesis showed that no significant difference existed in the accuracy of bracket placement and oral hygiene status between the two bonding techniques. The indirect bonding was found to involve less chairside time but more total working time compared with the direct bonding. The meta-analysis on bond failure rate demonstrated no significant difference between the direct and indirect bonding (RR = 1.13, 95% CI = 0.78–1.64, I² = 22%, P = 0.50). Consistent results were obtained in the subgroup analyses and sensitivity analyses.

Conclusion

Weak evidence suggested that the direct and indirect bonding techniques had no significant difference in bracket placement accuracy, oral hygiene status and bond failure rate, for bonding orthodontic brackets. The indirect bonding might require less chairside time but more total working time in comparison with the direct bonding technique. High-quality well-designed randomized controlled trials are needed before a conclusive recommendation could be made.

Electronic supplementary material

The online version of this article (10.1186/s12903-019-0831-4) contains supplementary material, which is available to authorized users.

Orthodontic treatment time: can it be shortened?

INTRODUCTION

In the literature, no consensus has been reached about orthodontic treatment time. Similarly, the determining factors of the latter have not yet been completely elucidated.

OBJECTIVE

The aim of the present article was to deepen the discussion on the major factors influencing orthodontic treatment time, as well as to present some strategies that have proven effective in controlling and shortening it.

METHOD

Based on evidences found in the literature, the method focussed in providing the basis for clinical decision-making.

CONCLUSIONS

Treatment time varies according to the type of malocclusion and treatment options. Orthodontist's influence, patient's characteristics and compliance are all decisive in determining treatment time, while the effects provided by orthodontic appliances and methods used to speed tooth movement up seem little effective.