Systematic review of self-ligating brackets

Public perception of the advertised claims of Damon® appliance system in Saudi Arabia: a cross-sectional survey-based study

INTRODUCTION

The clinical validity of self-ligating brackets' advertised claims, such as those for the Damon® appliance system, has been explored, but public awareness remains underexamined. This study assessed Saudi public perceptions of these claims.

MATERIALS AND METHODS

A web-based survey distributed via social media evaluated perceptions of Damon system claims, including treatment efficiency, patient discomfort, oral hygiene maintenance, and treatment esthetic results. Participants were also asked to outline their perception of Damon's appliance cost. Responses were ranked on a Likert scale and analyzed using the Chi-square test with Bonferroni corrections.

RESULTS

Of 918 adults, 11% were familiar with the Damon system. Among Damon appliance-aware respondents, 64.4% believed it was superior to traditional braces. Around 56.4% thought it required fewer visits, and 49.5% believed treatment time was shorter, though many were neutral or uncertain. Regarding tooth extraction needs, 43.6% agreed it required lower needs, while 48.5% believed it causes less discomfort. About 46.5% agreed it was easier to maintain oral hygiene, and 54.5% thought it provided better esthetic results. Notably, 52.5% mistakenly believed it was cheaper than traditional braces. However, no major association was found between socio-demographics and Damon appliance knowledge, but females were more likely to perceive it as superior (P = .012).

CONCLUSIONS

This study highlighted the dissimilarities between public perception and scientific evidence regarding the Damon system. These mixed findings suggest a need for guidelines in orthodontic advertising to prevent potential misinformation. Providing the public with reliable, evidence-based information is crucial for supporting informed decision-making in orthodontic care.

Endodontic implications of dental trauma: useful tips for primary dental care

Dental trauma is the fifth most common condition affecting human beings worldwide. The dental team can expect to encounter traumatic dental injuries in everyday practice. Dental trauma guidelines guide practice and should be available to the dental team faced with an acute presentation of injury in a patient of any age. The management of dental trauma and the endodontic materials available for intervention of its complications are rapidly evolving. This paper provides an important update for the primary dental care team regarding the endodontic management of dental trauma.

The Effect of MRI Exposure on the Shear Bond Strength and Adhesive Remnant Index of Different Bracket Types

Background/Objectives: Magnetic resonance imaging (MRI) is widely used in diagnostics, but its effects on orthodontic materials remain a concern. This study aimed to evaluate the impact of MRI exposure at 1.5 T and 3 T on the shear bond strength (SBS) and adhesive remnant index (ARI) of different orthodontic bracket types (metal, self-ligating, and ceramic). Methods: A total of 90 extracted human premolars were divided into three groups (control, 1.5 T, and 3 T MRI exposure). The three bracket types were bonded using Transbond XT adhesive and subjected to standardized polymerization. MRI scans were conducted using 1.5 T and 3 T machines with clinically relevant sequences. SBS was measured using a universal testing machine, and the ARI was assessed under a stereomicroscope. Statistical analysis was performed using Kruskal-Wallis and chi-square tests. Results: MRI exposure influenced SBS and the ARI differently across bracket types. Firstly, 3 T MRI exposure significantly reduced SBS in self-ligating (p = 0.017) and ceramic brackets (p = 0.014) compared to the control, whereas metal brackets showed no significant changes. ARI scores varied across MRI conditions, with metal and self-ligating brackets showing increased adhesive retention at higher field strengths. No significant differences were observed in ARI scores for ceramic brackets across MRI conditions. Conclusions: The clinical importance of understanding these results is that both patients and clinicians must be aware of inevitable changes that occur in SBS during MRI, since exposure to high-field MRI, particularly 3 T, may alter bond strength and adhesive failure characteristics.

Comparison of maxillary transversal changes between auxiliary beta-titanium expansion arch and miniscrew-assisted rapid palatal expansion

OBJECTIVE(S)

This study compared buccal bone thickness, dental inclinations and maxillary transverse width dimensions changes between auxiliary beta-titanium expansion arch (AEA) and miniscrew-assisted rapid palatal expansion (MARPE).

MATERIALS AND METHODS

The sample consisted of 29 patients, aged between 18 and 40 years, with transverse maxillary deficiency and treated without extractions, divided into two groups: group AEA: comprised 13 individuals (initial mean age: 29.23 ± 9.13 years) treated using auxiliary beta-titanium expansion arch; group MARPE: comprised 16 patients (initial mean age: 24.92 ± 7.60 years) treated with miniscrew-assisted rapid palatal expansion. Buccal bone thickness, dental inclinations and transverse width dimensions (dental, nasal base and jugular) were measured in cone-bean computed tomographies at pre- and post-treatment stages. The variables were compared using the independent t-test.

RESULTS

The buccal bone thickness was similar for both groups at the post-treatment stage. The second premolars were significantly more buccal inclined in the AEA group and the right maxillary first molars in the MARPE group. The intercanine and intermolar distances were statistically significantly greater in the MARPE group. Changes in dental arch transverse dimensions were significantly greater for the MARPE group.

CONCLUSION

Both treatment protocols corrected the maxillary transverse discrepancy; however, MARPE provided greater correction.

Evaluation of effects of brackets and orthodontic wires on intraoral scans: A prospective in-vivo study

OBJECTIVE

To evaluate any distortion produced by multibracket fixed orthodontic appliances on digital models obtained from intraoral scans (IOS), considering the presence of both brackets only and brackets/archwire combination.

SETTING/SAMPLE

The IOS data of the arches of 20 patients (12 females and 8 males; mean age = 15.55 ± 2.84 years) were acquired using the CS3600 intraoral scanner (Carestream Dental, Atlanta, USA), without any appliances (model A), with vestibular brackets alone (model B) and then with brackets and orthodontic archwire fitted (model C).

MATERIALS AND METHODS

Data were acquired between the months of January and October 2021 at the moment of indirect bonding phase. On each model, five intra-arch linear measurements were obtained (inter-canine, inter-premolar 1 and 2, inter-molar and arch depth), and after digital matching between model A and B (match 1) and A and C (match 2), the linear discrepancies were evaluated at 20 points (10 occlusal and 10 gingivolingual) previous identified on the reference model A. All measurements were performed using Geomagic Control X software (3D Systems, Morrisville, USA), and any dimensional variations and distortions were evaluated by the linear regression analysis and two-sample t-test (P ≤ .05).

RESULTS

The results show an almost perfect correlation between both models B and C and the reference model A, both as regards the intra-arch linear measurements and the linear discrepancies found at the 20 identified points.

CONCLUSIONS

Multibracket fixed orthodontic appliances do not produce any relevant distortions in digital models obtained via intraoral scanning. Therefore, the removal of archwire is not mandatory before IOS.

Canine retraction and anchorage loss using self-ligating and conventional brackets with sliding mechanics: A split-mouth clinical study

OBJECTIVE

Appliance biocompatibility, orthodontic treatment efficiency and patient convenience are the major issues confronting contemporary orthodontic practice. Very few studies have been published till date regarding the efficiency of self-ligating brackets as against conventional brackets. Hence, the present study was planned to compare the rate of canine retraction between self-ligating and conventional brackets and to determine the amount of anchorage loss during canine retraction.

METHODS

The present clinical study was designed as a prospective, observational study comprising of 25 patients requiring first premolar extraction as a part of orthodontic treatment. Self-ligating and conventional brackets were bonded using a split-mouth study design randomly. Retraction of canines was done with 150 grams of force using Dontrix gauge with E-chains. The study was conducted in relation to upper arch only, while the rate of retraction was evaluated every 4 weeks for 3 months. Average rates of retraction in 3 months were calculated. For anchorage loss, an acrylic guide plug was used in mid-treatment cast (T0) and after 3 months of retraction (T3). The statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA). Independent t-test was used to compare the means of the two variables studied, while Pearson's correlation coefficient was used to evaluate the correlation between the variables studied in the groups included. P < .05 was considered statistically significant.

RESULTS

The correlation coefficient between the average rate of canine retraction with self-ligating brackets vs. conventional brackets over a period of 3 months came out to be 0.6434, while on comparing the data in terms of anchorage loss over a period of 3 months, the respective correlation coefficient value was found to be 0.6659 with the results being statistically highly significant in either case (P < .001).

CONCLUSIONS

Self-ligating brackets showed double the amount of displacement compared to conventional brackets in some of the cases. Also, chair side time was significantly reduced with self-ligating brackets as against conventional brackets.

Self-Ligating Bracket Systems: A Comprehensive Review

Currently, ligature-free bracket technologies, including self-ligating brackets (SLBs), are all the rage in orthodontics. Self-ligating mechanisms have been shown to be more effective and less time-consuming in orthodontic treatment than traditional appliances due to their enhanced frictional properties. Crucial to the success of the multi-band/bracket method is the transmission of forces and moments from the bracket to the archwire. Advances in bracket design and ligation techniques are constantly being made to better distribute loads and increase the efficiency of leveling.

Knowledge on Applications of 3D Design and Printing in Dentistry Among Dental Practitioners in Saudi Arabia: A Questionnaire-Based Survey

Background: This knowledge, attitude, and practices (KAP) survey will provide baseline data and identify gaps that may facilitate understanding and further action to plan, implement, and evaluate practice toward 3D-printing technology among dental practitioners in Saudi Arabia.

AIMS AND OBJECTIVES

The present study aims to assess dental practitioners' self-reported knowledge, attitude, and practice of 3D printing in Saudi Arabia.

METHODOLOGY

A cross-sectional, closed-ended questionnaire of registered dental practitioners in Saudi Arabia was conducted. A sample size of 156 was considered for analysis. After obtaining approval from the Institutional Review Board, Riyadh Elm University, the research was conducted during the month of April 2022 amongst 154 registered dental practitioners. The research was distributed among dental health specialists either working in dental colleges, dental clinics, or both in government as well as private settings. Dentists who were not actively involved in 3D printing were excluded. SPSS software, version 25.0, (IBM Corp., Armonk, NY) was used to analyze the data.

RESULTS AND CONCLUSION

Of all dentists included in the study, 98% were found to be aware that 3D printing in dentistry is used in Saudi Arabia and 2 % were not aware of its usage in Saudi Arabia. In total, 78.60% of the dentists felt that 3D-printed implant guides made the placement of implants the most accurate and least complicated procedure, and 21.40% of the dentists felt it was the least accurate and most complicated procedure.

Ectopic Eye Tooth Management: Photobiomodulation/Low-Level Laser Emission Role in Root Resorption after Fixed Orthodontic Treatment

Aim: This study evaluates the role of low-level laser emission/photobiomodulation (LE/P) in quantitative measurements of root resorption (QRR). The application of LE/P performed after each orthodontic activation with four types of treatment intervention (TI) on the root resorption (RR) after fixed orthodontic treatment (FOT) of the upper arch with ectopic eye tooth/teeth [EET] was investigated. Materials and Methods: Thirty-two orthodontic patients scheduled for FOT were selected and assigned to the four groups. These were LE/P + Self ligating bracket (SLB), LE/P + Conventional bracket (CB), non-photobiomodulation (non-LE/P) + SLB and non-LE/P + CB. Standard management stages of FOT were followed in the maxilla. Each patient received a single application of LE/P labially/buccally and palatally, a total of five different points were used during each activation or appointment. The main outcome measure was QRR in maxillary anteriors before and after FOT, assessed via cone-beam computed tomography (CBCT) using 3D OnDemand software. Results: Insignificant QRR was found between before and after FOT in SLB, CLB, and LE/P, non-LE/P groups (p > 0.05). QRR in the SLB vs. CB and LE/P vs. non-LE/P group was significantly different in 11, 13, and 23 (p < 0.05). QRR in the LE/P + SLB group (p < 0.05) was significantly different in 11, 13, and 23 than that in the other groups. The most severe QRR was found on 13 (0.88 ± 0.28 mm and 0.87 ± 0.27 mm) and 23 (1.19 ± 0.14 mm and 1.16±0.13 mm) in the CB and non-LE/P group (p < 0.001). LE/P + SLB showed a highly significant superior outcome (p < 0.001) in relation to non-LE/P + CB, the QRR of 23 were 0.813 ± 0.114 mm and 1.156 ± 0.166 mm, respectively. Conclusion: Significantly higher amounts of QRR were found in EET patients after FOT treated with the CB, non-LE/P, and non-LE/P + CB system and warrant further investigation to explore potential specific causes.

A Novel Technique for Shortening Orthodontic Treatment: The “JET System”

We have developed a novel technique, the Jiyugaoka Enjoyable Treatment (JET) system, to complete orthodontic treatment in a short time. It entails the use of the regional acceleratory phenomenon (RAP), light continuous forces and low friction in cases involving extraction. In the JET system, tooth extraction not only creates space, but also triggers the RAP; thus tooth extraction accelerates orthodontic treatment. We describe for the first time how to use the JET system to shorten treatment time in a patient in whom four premolars were extracted. A 15 year old girl patient exhibited an Angle Class I bimaxillary protrusion with moderate crowding in the maxillary (−5.0 mm) and mandibular arches (−3.5 mm). Her facial appearance was slightly asymmetric, and her facial profile was convex. Immediately after the simultaneous extraction of the maxillary first premolars and mandibular second premolars, orthodontic treatment was started with a combination of passive self-ligating brackets and super-elastic nickel-titanium closed coil springs that provided orthodontic forces of less than 50 gf (1.8 ozf). The appliance was adjusted once a month. The total treatment time was 13 months. Cephalometric superimpositions showed a slight anchorage loss, and panoramic radiographs showed a slight apical root resorption but no significant reduction in the crest bone height. At the 3-year 6-month retention follow-up, stability was excellent. The JET system might shorten the orthodontic treatment period without serious anchorage loss or other adverse effects.

The nature and accuracy of Instagram posts concerning marketed orthodontic products: A cross-sectional analysis

OBJECTIVES

To scrutinize claims contained within Instagram posts related to six popular marketed orthodontic products.

MATERIALS AND METHODS

Three hundred publicly available Instagram posts were identified using the following Instagram hashtags: #carrieremotion, #damonbraces, #invisalign, #acceledent, #propelorthodontics, and #myobrace. Pilot coding was undertaken on a subset of claims (n = 50) and a coding guide was developed. The associated claims were categorized under 24 recognized themes and their accuracy assessed on a five-point scale.

RESULTS

Of 1730 posts screened, 300 were included for analysis. The majority of posts were based on photographs (n = 244, 81.3%) with the remainder (n = 56, 18.7%) including videos. Half of the posts involved a picture of the product in isolation (n = 150, 50%), with clinical cases presented in a minority (n = 99, 33%). Overall, 472 claims were included with treatment duration being the most frequent theme (n = 125, 26.5%). In terms of accuracy, most of the claims were judged to be "false" (n = 283, 60%) with less than 2% considered "objectively true."

CONCLUSIONS

Most of the claims relating to six popular marketed orthodontic products concerned treatment duration. The vast majority of these claims were not supported by evidence and were judged to be false. Efforts should be made to promote the provision of accurate orthodontic information and to verify marketing claims on social media platforms.

Effects of self-ligating brackets and other factors influencing orthodontic treatment outcomes: A prospective cohort study

Objective

The purpose of this study was to evaluate the effects of self-ligating brackets (SBs) and other factors that influence orthodontic treatment outcomes.

Methods

This two-armed cohort study included consecutively treated patients in a private practice. The patients were asked to choose between SBs and conventional brackets (CBs); if any patient did not have a preference, he or she was randomly allocated to the CB or SB group. All patients were treated using an identical archwire sequence. Evaluated parameters were as follows: treatment duration, number of bracket failures, poor oral hygiene, poor elastic wear, extraction, use of orthodontic mini-implants (OMI), OMI failure, American Board of Orthodontics (ABO) Discrepancy Index (DI), arch length discrepancy, and ABO Cast-Radiograph Evaluation (CRE) score. Stepwise regression analysis was performed to generate the equation for prediction of the CRE.

Results

The final sample comprised 134 patients with an average age of 22.73 years. The average DI, CRE, and treatment duration were 21.81, 14.25, and 28.63 months, respectively. Analysis of covariance showed a significant difference in CRE between the CB and SB groups after adjusting for the effects of confounding variables. Stepwise regression analysis using four variables, namely extraction, SB use, poor elastic wear, and additional appliance use, could explain only 25.2% of the variance in the CRE.

Conclusions

Although the CRE was significantly better for CBs than for SBs, the clinical significance of this result seems to be limited. Extraction, SB use, poor elastic wear, and additional appliance use may have significant effects on treatment outcomes.

Is there any difference between conventional, passive and active self-ligating brackets? A systematic review and network meta-analysis

AIM

To test the null hypothesis that there was no difference in treatment efficiency between therapies undertaken with conventional (CBs), passive self-ligating (PSLBs) or active self-ligating (ASLBs) brackets.

MATERIALS AND METHODS

An electronic search was performed in 3 data bases (Pubmed, Web of Science, Cochrane Library) from their origin up to January 2019. Additional references were hand searched. Search was strictly restricted to randomized controlled trials (RCTs) and split-mouth design studies (SMDs). RCTs and SMDs were initially processed separately and subsequently combined in a network meta-analysis. The following variables were evaluated: treatment duration, number of visits, occlusal outcomes, alignment rate, transverse arch dimensional changes, incisor position modification, rate of space closure, anchorage loss, bond failure, root resorption, perception of discomfort during the initial phase of alignment, time to ligate in or to untie an archwire, periodontal variables, quality of life.

RESULTS

On 229 papers, 30 RCTs and 9 SMDs were finally included in this study. Out of 85 comparisons, 16 only revealed statistically significant differences. It was quicker to untie and ligate an 0.014 NiTi arch from/in 6 ASLBs anterior ceramic brackets compared to 6 ceramic CBs. It was also more painful to insert and remove an 0.019×0.025 SS wire in/from PSLB's brackets compared to CB's attachments. Compared to conventional brackets, there was less maxillary incisor proclination with PSLBs in non-extraction cases. Moreover, there was less bleeding on probing 4-5 weeks after bonding with PSLBs compared to CBs brackets. The only significant difference between ASLBs and PSLBs was that alignment was 10 days faster with active self-ligating braces compared with passive self-ligating braces even if treatment duration between ASLBs and PSLBs was not significantly different. The network meta-analysis revealed that IMPA was greater in extractions cases with CBs compared with both ASLBs (+2,5°) and PSLBs (+1,6°).

CONCLUSIONS

The vast majority of the studied variables did not show any significant differences between the three types of brackets. The most significant findings were that it was quicker to insert and remove archwires from ASLBs compared to CBs, and it was more painful to insert and remove an 0.019×0.025" stainless steel wire in/from PSLBs compared to CBs. The major difference between ASLBs and PSLBs was that alignment was 10 days faster with active self-ligating braces compared with passive self-ligating braces even if treatment duration between ASLBs and PSLBs was not significantly different. Most of the claims put forward by the suppliers were not substantiated by our network meta-analysis.

Qualitative and Quantitative Evaluation of Different Types of Orthodontic Brackets and Archwires by Optical Microscopy and X-ray Fluorescence Spectroscopy

The wear behaviour and chemical composition of orthodontic components influence the mechanical characteristics of a fixed orthodontic treatment. The purpose of this paper is to evaluate the surface alterations of different types of brackets (aesthetic, metallic, and conventional self-ligating) and archwires (superelastic and thermal) subjected to wear tests through optical microscopy and, subsequently, to identify the chemical elements of accessories by X-ray fluorescence. The cycles (5000 for each bracket and 10,000 for each wire) of the tribological test were carried out in dry conditions inside a machine that allows alternating sliding. The results of the study highlighted different wear behaviours even within the same type of brackets and archwires. The monocrystalline sapphire brackets maintain their aesthetic properties despite traces of wear inside the slots and contain minimal amounts of nickel. Superelastic NiTi archwires have a better overall rating than thermal wires, as they do not show significant surface wear alterations.

Perception of Iraqi Orthodontists and Patients toward Accelerated Orthodontics

Background/Purpose. In the literature, no consensus about the duration of orthodontic treatment has been reached out. This study aimed to identify orthodontist's and patient's perception about the time of orthodontic treatment and their willingness to undergo and pay for various acceleration techniques and procedures. Materials and Methods. An electronic survey was conducted from August to October 2020. The questionnaire consisted of 20 multiple choice questions which was designed and emailed to members of the Iraqi Orthodontic Society and self-administered to patients in several orthodontic centers in Baghdad. The questionnaire included questions about the perception toward the duration of orthodontic treatment, approval of different procedures used to reduce treatment time, and how much fee increment they are able to pay for various techniques and appliances. Descriptive and chi-square test statistics were used, and the level of significance was set at p ≤ 0.05. Results. The response rate was 78.7%. The willingness for additional techniques and procedures was rated in the following order: customized appliances: 50.8% orthodontists and 38.4% patients, followed by intraoral vibrating devices: 49.2% orthodontists and 38.1% patients, piezocision: 10.2% orthodontists and 8.2% patients, and corticotomies: 8.1% orthodontists and 5.9% patients. Most orthodontists were willing to pay up to 40% of treatment income for the acceleration procedure, while the payment of patients was up to 20%. Conclusion. Both orthodontists and patients were interested in techniques that can decrease the treatment duration. Noninvasive accelerating procedures were more preferable by orthodontists and patients than invasive surgical procedures.

Failure rates among metal brackets cured with two high-intensity LED light-curing lamps: an in vivo study

OBJECTIVE

The objective of this split-mouth clinical trial was to compare bonding failure rates of metal brackets bonded with two different light-emitting diode (LED) light-curing lamps with different high-intensity power outputs.

MATERIALS AND METHODS

Forty patients were included for a total of 800 brackets that were randomly bonded (left and right sides in a 1:1 ratio) in maxillary and mandibular arches using two different LED devices. An LED of 3200 mW/cm2 and an LED of 5000 mW/cm2 were used in this split-mouth clinical trial. Bonding failures during the initial 6 months of orthodontic treatment were recorded as maxillary versus mandibular, anterior teeth versus posterior teeth, and left side versus right side.

RESULTS

Five dropouts were recorded for discontinuing orthodontic treatment and 700 brackets were analysed in total. The bonding failure rates for 3200 and 5000 mW/cm2 LEDs were 6.0 and 7.4 per cent, respectively (P = 0.450), which were not statistically significantly different. There were no significant differences in bracket survival rates between the LEDs used (P = 0.866). The posterior teeth presented a higher index of bond failures (odds ratio, 3.14; 95% confidence interval, 1.68-5.87; P < 0.001).

LIMITATIONS

Direct comparison was only done between two high-intensity LED lights rather than against conventionally used halogen lights.

CONCLUSION

Similar bonding failures were recorded using both LED devices (3200 and 5000 mW/cm2). Significantly more bonding failures occurred in premolar teeth than in anterior teeth.

Direct 3D Printing of Clear Orthodontic Aligners: Current State and Future Possibilities

The recent introduction of three-dimensional (3D) printing is revolutionizing dentistry and is even being applied to orthodontic treatment of malocclusion. Clear, personalized, removable aligners are a suitable alternative to conventional orthodontic appliances, offering a more comfortable and efficient solution for patients. Including improved oral hygiene and aesthetics during treatment. Contemporarily, clear aligners are produced by a thermoforming process using various types of thermoplastic materials. The thermoforming procedure alters the properties of the material, and the intraoral environment further modifies the properties of a clear aligner, affecting overall performance of the material. Direct 3D printing offers the creation of highly precise clear aligners with soft edges, digitally designed and identically reproduced for an entire set of treatment aligners; offering a better fit, higher efficacy, and reproducibility. Despite the known benefits of 3D printing and the popularity of its dental applications, very limited technical and clinical data are available in the literature about directly printed clear aligners. The present article discusses the advantages of 3D printed aligners in comparison to thermoformed ones, describes the current state of the art, including a discussion of the possible road blocks that exist such as a current lack of approved and marketed materials and limited existence of aligner specific software. The present review suggests the suitability of 3D direct printed aligners is superior to that of thermoformed manufactured aligners because of the prior’s increased accuracy, load resistance, and lower deformation. It is an overall more stable way to produce an aligner where submillimeter movements can make a difference in treatment outcome. Direct 3D printing represents a complex method to control the thickness of the aligner and therefore has a better ability to control the force vectors that are used to produce tooth movement. There is currently no other approved material on the market that can do this. The conclusion of this article is that we encourage further in vitro and in vivo studies to test these new technologies and materials.

Multiple Idiopathic Cervical Root Resorption: A Challenge for a Transdisciplinary Medical-Dental Team

The goal of this perspective article is to use multiple idiopathic cervical root resorption (MICRR) as a model to demonstrate the need for transdisciplinary collaborations, from basic science to treatment planning, to improve the quality of health care for all. This is not a review of the literature on the current state of MICRR. Tooth root resorption is a normal physiological process required for resorption and exfoliation of primary teeth; however, root resorption of adult teeth is largely pathological. MICRR is an aggressive form of external root resorption, which occurs near the cemento-enamel junction (CEJ). The cause of MICRR remains elusive, however, it is mediated primarily by osteoclasts/odontoclasts. Accumulating case studies and experiments in animal models have provided insights into defining the etiologies and pathophysiological mechanisms for MICRR, which include: systemic conditions and syndromes, inherited genetic variants affecting osteoclast/odontoclast activity, altered periodontal structures, drug-induced root resorption and rebound effects after cessation of anti-resorptive treatment, chemotherapy, exposure to pets or viral infections, and other factors such as inflammatory conditions or trauma. To determine the causative factors for MICRR, as well as other oral-dental conditions, at minimum, a comprehensive health history should be collected for all patients by dental care providers, discussed with other health care providers and appropriate collaborations established. The examples highlighted in this perspective emphasize the need for transdisciplinary research collaborations coupled with integrated management strategies between medicine and dentistry in order to identify cause(s) early and improve clinical outcomes.

Do orthodontists aim to decrease the duration of fixed appliance treatment?

OBJECTIVES:

The aim of the present study was to investigate the trends in the use of fixed appliance and accelerated orthodontics to decrease the treatment duration. Further, this study aimed to assess the effect of demographic factors on the participant's choice of treatment modality.

METHODS:

This was a cross-sectional study in the form of questionnaire-based online survey especially designed and distributed to 265 orthodontists via email. The questions aimed to collect basic information about the participants and respondents’ choices for decreasing the treatment duration. The data were analyzed according to gender, level of academic education and years of clinical experience using Chi-square test.

RESULTS:

A response rate of 85.2% was reported. Most of the orthodontists aimed to reduce the treatment duration by the biomechanical (66.8%) and surgical approaches (27.4%). The use of sliding mechanics (69.4%) and one-step retraction was more common (66.3%). MBT bracket prescription was more prevalent (51.7%), followed by Roth (41.1%). Conventional brackets were used more than self-ligating brackets, and aesthetic brackets were avoided by one third of the respondents. NiTi wires were the most commonly used wires during the alignment stage (44.2%). However, the effect of gender, years of clinical experience and specialty level of education showed some effects on the use of certain techniques and clinical practice of the respondents.

CONCLUSIONS:

Most of the orthodontists aimed to decrease orthodontic treatment duration by using biomechanical and surgical approaches. Gender and clinical experience to a certain extent affected the participants’ choice during orthodontic treatment.

Factors influencing treatment efficiency

OBJECTIVES

The purpose of this cohort study was to evaluate the effect of self-ligating brackets (SB) and other related factors that influence orthodontic treatment time.

MATERIALS AND METHODS

This was a two-armed prospective study. Consecutively treated patients who were recruited from a private practice were enrolled and asked to choose between SB and conventional brackets (CB). If the patient did not have a preference, that patient was randomly allocated. An identical archwire sequence was used, and all patients were treated by a single orthodontist. Treatment duration, number of bracket failures, poor oral hygiene, poor elastic wear, whether or not to orthodontic mini-implants (OMI) were used, OMI failure, extraction, American Board of Orthodontics Discrepancy Index, and arch length discrepancy were measured and statistically analyzed using t-tests, correlation analysis, and analysis of covariance (ANCOVA). Stepwise regression analysis was conducted to generate an equation to predict treatment duration.

RESULTS

A total of 134 patients with an average age of 22.73 years were included. The average treatment duration was 28.63 months. ANCOVA showed no significant difference in treatment duration between CB and SB. Stepwise regression analysis could explain 64.6% of the variance in treatment duration using five variables.

CONCLUSIONS

SB did not exhibit a significant reduction in treatment time as compared with CB. Patient cooperation, extractions, and malocclusion severity had a significant impact on treatment duration.

An in vitro assessment of the influences of different wire materials and bracket systems when correcting dental crowding

A recently developed orthodontic wire alloy known as GUMMETAL® is claimed to deliver more physiological forces to correct dental mispositioning. However, its mechanical characteristics have not been fully characterized yet. This study aimed to determine and compare the elastic properties of different wire alloys, such as nickel-titanium (NiTi), stainless steel (SS), and GUMMETAL®, and assess their unloading forces when combined with either conventional or self-ligating brackets (CL and SL) when correcting dental crowding. All wires had a 0.016″ cross-section diameter. A three-point bending test was performed to assess the maximum deflection of each wire. Then, a subsequent analysis measured the unloading force for each wire/bracket system in a dental crowding clinical simulation device. The test was carried out in a universal testing machine with a cross-speed displacement of 0.5 mm/min. Data were recorded in different ranges and statistically evaluated using two-way analysis of variance. GUMMETAL® displayed higher unloading mean forces in SL brackets (2228.78 cN) than CL brackets (1967.38 cN) for the 1.6-3.0 deflection interval (p = 0.018). Within this interval, NiTi showed higher forces when used with CL brackets (2683.06 cN) than with SL brackets (1179.66 cN) (p < 0.0001). For the CL bracket systems, SS wires showed higher forces (2125.31 cN) in the 1.0-1.6 deflection interval than the other two wire alloys (NiTi, 1541.52 cN and GUMMETAL®, 852.65 cN) (p < 0.0001). SS wires also displayed lower forces with SL brackets (1844.01 cN) than in CL brackets (2125.31 cN) (p = 0.049). Thus, only GUMMETAL® revealed to be an optimal choice for SL brackets, whereas NiTi for CL brackets.

Comparative evaluation of square and rectangular slot three-point play behavior

The play between bracket slots and archwires affects tooth movement and the transmission of orthodontic force by multi-bracket appliances. We assessed play by quantifying the play behavior of three-point brackets and comparing the amount of play that occurred with square and rectangular slots, respectively, by using archwires of various sizes. Horizontal play with the square slot was significantly smaller than that with the rectangular slot. These data demonstrate that brackets with square slots can more effectively bring about tooth movement in the labio-lingual direction and control rotational movement with round and square archwires. Since the horizontal and vertical play ratios for the round and square wires within the square slot were approximately 1.0, three-dimensional tooth movement may also be achieved with uniform play in the vertical and horizontal directions.

Impact of coronavirus pandemic in appointments and anxiety/concerns of patients regarding orthodontic treatment

Objective

To evaluate the impact of the coronavirus pandemic and the quarantine in orthodontic appointments, and patients' anxiety and concerns about their ongoing orthodontic treatment.

Settings and sample population

Patients from private dental clinics of two orthodontists that were undergoing active orthodontic treatment.

Material and methods

An online anonymous questionnaire regarding their anxiety about the coronavirus situation, availability/acceptance to attend an appointment, among others, was answered by orthodontic patients. Descriptive statistics with percentages was performed and responses were compared between sexes, cities, and association of the feelings/level of anxiety of patients and willingness to attend an appointment were performed with chi‐square, independent t test, one‐way ANOVA and Tukey's tests.

Results

The questionnaire was answered by 354 patients (231 female; 123 male) with mean age of 35.49 years. Most patients are respecting the quarantine, 44.7% related to be calm and 46.3% afraid or anxious. The level of anxiety was greater for females than males. There was significant association of the level of anxiety and the willingness to attend an appointment. The greatest concern of patients was delay in the end of treatment.

Conclusion

The quarantine and coronavirus pandemic showed to have impact on orthodontic appointments and patients’ anxiety. Patients willing to attend an orthodontic appointment presented significantly lower level of anxiety than patients that would not go or would go only in urgency/emergency. Females were more anxious than males about coronavirus pandemic, quarantine and impact on their orthodontic treatments. Delay in treatment was the greatest concern of patients undergoing orthodontic treatment.

Comparison of changes in the dental transverse and sagittal planes between patients treated with self-ligating and with conventional brackets

INTRODUCTION

Several advantages have been established regarding the efficiency of self-ligating brackets (SL). In spite of some controversy surrounding this question in the literature, clinical results confirm that "arch development" requires fewer extractions.

OBJECTIVE

The objective of this study was to compare changes in the transverse and sagittal planes in patients treated with conventional ligating brackets (CL)as well as in patients treated with SL brackets and oversized arches.

METHODS

A sample was selected from a pool of 300 consecutive cases treated by a single clinician: 51 patients with SL brackets and oversized wires, and 55 with CL brackets. These two groups were compared with a control group of 20 patients. All plaster models were scanned and dental landmarks were measured to identify changes from commencement (T0) to conclusion (T1) of treatment. Lateral cephalograms were analyzed for changes in the lower incisor (IMPA) and the first lower molar distal angulation (MAng). Intraoperator reliability was tested with linear regression analysis. To assure all groups were comparable at T0, an ANOVA test with a 95%confidence interval (CI) was performed for all values. To assess changes from T0 to T1 in all groups, a Student's t-test with 95% CI was used. Finally, results from the three groups were compared using an ANOVA-test (95% CI) and a post-hoc test.

RESULTS

Increases in all the transverse variables were recorded in the two groups treated (SL and CL), except for the lower intercanine distance in the SL group. IMPA difference from T0 to T1 was higher in the CL group, and molar distal angulation (MAng) took place in the SL group.

CONCLUSIONS

Self-ligating brackets with oversized arches and conventional ligating brackets showed increases in all variables in the transverse plane, except for the SL group at the mandibular intercanine distance. In comparison with the CL group, fewer different IMPA values were observed in the SL group, in which distal molar angulation occurred.

Impact of passive self-ligation and conventional elastic ligation on orthodontic force in the simulation of a mandibular lateral incisor linguoversion

INTRODUCTION

This study compared three-dimensional forces delivered to the displaced tooth and its adjacent teeth between passive self-ligation (PSL) and conventional elastic ligation (CL) in simulation of mandibular lateral incisor linguoversions.

METHODS

A multisensor system was used to measure three-dimensional forces delivered to brackets attached to the mandibular left central incisor, lateral incisor, and canine (FDI tooth numbers 31, 32, and 33, respectively). Two ligation methods (PSL and CL), 3 nickel-titanium (0.014-inch) archwires similar to the arch form of normal occlusion, and 2 displacements (1 and 4 mm) were tested.

RESULTS

In 1-mm displacement, forces were significantly smaller in CL than in PSL at 32 in the labial direction and larger at 31 in the mesial direction for all 3 types of archwires (P <0.01 for both). For 2 of 3 archwires, forces were larger in CL than in PSL at 33 in the lingual direction (P <0.01). In 4-mm displacement, forces were significantly larger in CL than in PSL at 31 in the mesial direction and significantly smaller in CL than in PSL at 33 in the distal direction for all 3 archwires (P <0.05 and P <0.01, respectively). Mean forces in the vertical direction were small, ranging from -0.05 to 0.05 N.

CONCLUSIONS

Under a small amount of displacement, force magnitude in PSL was smaller than that in CL at the displaced tooth in labial-lingual directions. Under a large amount of displacement, a more "open coil spring effect" was significantly obtained in CL than PSL at both adjacent teeth of the displaced tooth.

Comparison of anchorage loss between conventional and self-ligating brackets during canine retraction - A systematic review and meta-analysis

INTRODUCTION

Anchorage is defined as the resistance to unwanted tooth movement. In orthodontics, loss of anchorage can be detrimental to treatment. The proponents of orthodontic self-ligating brackets (SLB) advocate the use of extremely light forces thereby reducing anchorage burden. Therefore, the aim of this study was to compare anchorage loss during canine retraction between conventional brackets (CB) and self-ligating brackets.

METHODS

An electronic search was conducted on the Cochrane database, Scopus, Web of Science, PubMed, Dental & Oral Science and CINAHL, along with handsearching Google Scholar and clinicaltrials.gov. Randomized or non-randomized clinical trials published in the English language on human subjects were included. Orthodontic patients undergoing canine retraction after premolar extraction bonded with self-ligating brackets as the intervention and conventional brackets as the control group in a split mouth design were included. Primary outcome studied was anchorage loss; secondary outcomes were retraction velocity and total amount of canine retraction. Two researchers carried out data extraction and study selection independently. The risk of bias was calculated using the Cochrane's Risk of Bias Assessment tool. The RevMan software was used for quantitative synthesis of data. Effect estimate of the primary and secondary outcomes was expressed using weighted mean difference and 95% confidence intervals (CIs). Heterogeneity of the studies was evaluated using the Cochrane's test for heterogeneity (I² Test); subgroup and sensitivity analyses were performed to investigate sources of heterogeneity among the studies.

RESULTS

Results of the literature search across all databases yielded 10,439 hits, out of which five studies were included in the qualitative synthesis that met the inclusion criteria. Four studies were randomized control trials (RCTs) where as one was a non-randomized control trial, with 100 subjects included in this systematic review. All studies used a split mouth design. Of the five studies included, only one reported significant differences between CB and SLB for anchorage loss, retraction velocity and total amount of canine retraction (P-value≤0.001). Four studies were included in the meta-analysis, which showed no difference in the amount of anchorage between self-ligating and conventional brackets (weighted mean difference - 0.22; 95% CI [-0.82, 0.38]; P=0.48). Multiple subgroup analyses further revealed there were no significant differences between the intervention and control groups for all outcomes studied.

CONCLUSION

This systematic review and meta-analysis found insufficient evidence to suggest a significant difference in anchorage loss between the CB and SLB groups. The scarcity of current evidence dictates that further studies are needed to canonically establish the clinical superiority of one over the other.

REVIEW REGISTRATION

PROSPERO 2019 CRD42019133217.

"In Vitro" Study About Variables that Influence in Arch Friction with Conventional and Self-Ligating Brackets

Many advantages have been described surrounding self-ligating (SL) brackets compared to metallic conventional ligating (CL) brackets, such as: Less total treatment time, alignment efficiency, patient comfort, plaque retention, and low friction. The objective of this in vitro simulation was to know the variables that affect arch displacement in CL and SL brackets-active (ASL) and passive (PSL)-and analyze if static friction values are affected by bracket design, arch wire section, kind of ligature, and use of a friction reducer agent (FRA) in a wet state. Larger values of static friction were found in CL with metallic ligature (ML) (8.01 ± 1.08 N/mm) and elastic ligature (EL) (6.96 ± 0.48 N/mm). Lower values were found in PSL brackets combined with FRA (0.58 ± 0.21 N/mm). The study was carried out using different stereographical models of a maxillary upper right quadrant with canine, first and second premolar, and first molar bonded brackets. A section of 25 mm of 0.019 × 0.025" stainless steel arch with a rectangular section (SS) and hybrid section (HY) was inserted into the different bracket models. Static friction values were collected using a universal test machine in wet conditions and testing the effect of a friction reducer agent (FRA). To assure the reliability of the study, different wire combinations were repeated after two weeks by the same operator and a linear analysis of regression was done. Each bracket model analysis-with the different wires, use of the FRA, and comparison among brackets in similar conditions-was done using an ANOVA test with a confidence interval of 95% and comparative Post-Hoc tests (LSD). In this in vitro simulation we found higher static friction values in CL compared to ASL and PSL. In PSL, lower values were achieved. CL brackets using ML showed the highest static friction values with a great variability. In this setting, the use of HY wires did not reduce static friction values in ASL and PSL, while in CL brackets with EL friction the values were reduced significantly. An FRA combined with ASL reduced significantly static friction values but not with PSL. In the case of CL, the FRA effect was higher with SS and better than with HY wires. ML values were similar to ASL static friction. The direct extrapolation of the results might be inaccurate, since all these findings should be tested clinically to be validated.

Comparison of WALA ridge and dental arch dimensions changes after orthodontic treatment using a passive self-ligating system or conventional fixed appliance

Objective

To compare changes in WALA ridge and mandibular dental arch dimensions in orthodontic patients treated with a passive self-ligating system and conventional appliances.

Design

Original paper.

Setting

Orthodontic department at Inga University Center, Maringá, PR, Brazil.

Materials and Methods

Pretreatment (T1) and posttreatment (T2) dental casts of 60 patients with Class I malocclusion treated with slight to moderate crowding that were divided into two groups. Group 1: 30 patients treated with a passive self-ligating system, at a mean initial age of 17.68 years and mean treatment time of 2.31 years. Group 2: 30 patients treated with conventional appliances, at a mean initial age of 19.23 years and mean treatment time of 2.56 years. Measurements were taken using a digital caliper directly on pre and posttreatment dental casts to evaluate the transversal dimension behavior of the mandibular dental arch and the WALA ridge width.

Results

Self-ligating group presented an increase in WALA ridge width and mandibular transversal dimensions significantly greater than the conventional group, with the exception of intermolar cusp tip distance and intercanine WALA ridge. There was no statistically significant difference between the groups. There was also observed a significantly greater increase of the transversal buccal axis dimensions in the premolar area when compared to the WALA ridge increase in both groups.

Conclusions

Treatment with a passive self-ligating system resulted in a significantly greater increase of the WALA ridge width and mandibular arch dimensions when compared to conventional appliance.

Clinical effectiveness of orthodontic treatment on smile esthetics: a systematic review

Objectives: The aim of this systematic review is to identify how different types of orthodontic interventions affect the esthetics of the smile, any time after orthodontic treatment.

Materials and methods: A systematic search of the literature was carried out using 5 electronic databases (PubMed, Embase, The Cochrane Library, Scopus, Dentistry and Oral Sciences Source) that included articles until October 2017. Randomized and non-randomized controlled clinical trials, case–control observational studies, and cohort and cross-sectional studies with validated data collection and/or follow-up periods reporting on orthodontic interventions that changed the smile any time after orthodontic treatment were part of the study protocol. Only studies that were published in the English language and those that had human patients of any age and gender who underwent orthodontic treatment were included.

Results: A total of 814 articles were found and 9 of them were included (7 cohort and 2 cross-sectional studies). Among the selected articles, 8 stated the type of orthodontic intervention used during treatment and 1 did not specify the intervention. Eight articles were judged of moderate risk and 1 had high risk of bias.

Conclusion: Orthodontic treatment affects the esthetics of the smile in three dimensions. There was slight evidence that extractions do not affect the smile width and buccal corridors area. Evidence on palatal expansion was controversial. The remaining existing data evidence that investigated smile esthetics after orthodontic treatment was uncertain. Therefore, more validated, evidence-based studies are needed.

Comparison of the efficacy of tooth alignment among lingual and labial brackets: an in vitro study

Background/objective

The aim of this study was to evaluate the efficacy of tooth alignment with conventional and self-ligating labial and lingual orthodontic bracket systems.

Materials/methods

We tested labial brackets (0.022″ slot size) and lingual brackets (0.018″ slot size). The labial brackets were: (i) regular twin brackets (GAC-Twin [Dentsply]), (ii) passive self-ligating brackets including (Damon-Q® [ORMCO]; Ortho classic H4™ [Orthoclassic]; FLI®SL [RMO]), and (iii) active self-ligating brackets (GAC In-Ovation®C [DENTSPLY] and SPEED™[Strite]). The lingual brackets included (i) twin bracket systems (Incognito [3M] and Joy™ [Adenta]), (ii) passive self-ligating bracket system (GAC In-Ovation®LM™ [Dentsply]), and (iii) active self-ligating bracket system (Evolution SLT [Adenta]). The tested wires were Thermalloy-NiTi 0.013″ and 0.014″ (RMO). The archwires were tied to the regular twin brackets with stainless steel ligatures 0.010″ (RMO). The malocclusion simulated a displaced maxillary central incisor in the x-axis (2 mm gingivally) and in the z-axis (2 mm labially).

Results

The results showed that lingual brackets are less efficient in aligning teeth when compared with labial brackets in general. The vertical correction achieved by labial bracket systems ranged from 72 to 95 per cent with 13″ Thermalloy wires and from 70 to 87 per cent with 14″ Thermalloy wires. In contrast, the achieved corrections by lingual brackets with 13″ Thermalloy wires ranged between 25-44 per cent and 29-52 per cent for the 14" Thermalloy wires. The anteroposterior correction achieved by labial brackets ranged between 83 and 138 per cent for the 13″ Thermalloy and between 82 and 129 per cent for the 14″ Thermalloy wires. On the other hand, lingual brackets corrections ranged between 12 and 40 per cent for the 13″ Thermalloy wires and between 30 and 45 per cent for the 14″ Thermalloy wires.

Limitation

This is a lab-based study with different labial and lingual bracket slot sizes (however they are the commonly used ones in clinical orthodontics) and study did not consider saliva, periodontal ligament, mastication and other oral functions.

Conclusions

The effectiveness of lingual brackets in correcting vertical and anteroposterior displacement achieved during the initial alignment phase of orthodontic treatment is lower than that of the effectiveness of labial brackets.

Cinco tópicos tecnológicos na ortodontia atual

O artigo explorou cinco tópicos de interesse na ortodontia considerados na realidade clínica da especialidade. Muitas vezes com o apelo comercial, marketing, mídias sociais e até mesmo em eventos científicos, ortodontistas são instigados a absorverem novas tecnologias como se fossem indispensáveis para o sucesso clínico e que seriam vistos como retrógrados se não adotarem as novas práticas. O objetivo deste trabalho foi elucidar os temas mini-implantes ortodônticos, tomografia computadorizada de feixe cônico, bráquetes autoligados, scanner intraoral e alinhadores transparentes e mostrar que toda tecnologia deve ser vista com critério e estudada antes de ser adotada indiscriminadamente. A finalidade do tratamento ortodôntico deve ser pela melhor solução possível para a realidade do paciente, através de treinamento, discernimento e empenho do profissional. E isto só pode ser alcançado com estudo, educação e individualização de cada caso clínico.

Effect of different combinations of bracket, archwire and ligature on resistance to sliding and axial rotational control during the first stage of orthodontic treatment: An in-vitro study

OBJECTIVE

This study was performed to explore the effect of different bracket, archwire, and ligature combinations on resistance to sliding (RS) and rotational control in first-order angulation.

METHODS

Three types of brackets (multi-level low friction [MLF], self-ligating, and conventional brackets) coupled with four nickel-titanium archwires (0.012, 0.014, 0.016, and 0.018-inch diameter) and two stainless steel ligatures (0.20 and 0.25 mm) were tested in different first-order angulations (0°, 2°, 4°, 6°, 8°, 10°, 15°, 20°) by using an Instron universal mechanical machine in the dry state at room temperature. RS value was evaluated and compared by one-way ANOVA.

RESULTS

Under the same angulation, the RS values showed the following order: conventional brackets > MLF brackets > self-ligating brackets. The RS was the highest for conventional brackets and showed a tendency to increase. The RS for MLF brackets coupled with thinner archwires and ligatures showed a similar tendency as the RS for the self-ligating bracket. In contrast, the RS for MLF brackets coupled with thicker archwires and ligatures increased like that for conventional brackets. MLF brackets showed the greatest range of critical contact angles in first-order angulation.

CONCLUSIONS

The RS in first-order angulation is influenced by bracket design, archwire, and ligature dimension. In comparison with self-ligating and conventional brackets, MLF brackets could express low friction and rotational control with their greater range of critical contact angles.

Camouflage treatment of skeletal Class III malocclusion in an adult cleft-palate patient using passive self-ligating system

This case report describes the successful camouflage treatment to correct a moderate skeletal Class III malocclusion in a 19-year-old male cleft-palate patient. Early closure of the palate produced palatal scar tissue that inhibited midfacial growth, causing maxillary arch deficiency, severe maxillary crowding, and anterior and posterior crossbites. Combined surgical-orthodontic therapy would have been the preferred treatment of choice; however, the patient declined this option because of surgical risks and costs. Therefore, nonextraction camouflage treatment using a passive self-ligating bracket system was used. Treatment aims including expansion of the maxillary arch and correction of the anterior and posterior crossbites were achieved without the use of an additional maxillary arch expander or other auxiliary appliances. This treatment resulted in satisfying facial esthetics and a normal dental occlusion.

Comparison of Changes in Dental Arch Dimensions in Cases Treated with Conventional Appliances and Self-Ligating Damon System

Proposition:

The objective of this study was to compare changes in maxillary and mandibular dental arch dimensions in cases treated nonextraction with conventional appliances and self-ligating Damon System.

Materials and Methods:

initial (T1) and final (T2) dental casts of 45 patients with Class I malocclusion treated nonextraction, with slight to moderate crowding, divided into two groups. Group 1: 21 patients treated with self-ligating Damon appliances, at a mean initial age of 18.37 years and mean treatment time of 2.11 years. Group 2: 24 patients treated with conventional appliances, at a mean initial age of 19.50 years and mean treatment time of 1.99 years. The model analysis was performed; Little irregularity index was used to evaluate crowding and arch form was evaluated by measurements in maxillary and mandibular arches including intercanine, interpremolar (first and second premolars) and intermolar distances and arch length. The intragroup comparison was performed with dependent t or Wilcoxon tests and intergroup comparison, with independent t or Mann Whitney tests.

Results:

In intergroup comparison of treatment changes (T2-T1) the Damon group presented an increase in maxillary transversal dimensions significantly greater than the conventional group. The change in maxillary arch length did not show difference between the groups. Regarding the mandibular arch, the Damon group presented a significantly greater increase in intercanine and inter first premolars than the conventional group. In The mandibular arch length, the greater and significant increase was observed in the groups of patients treated with conventional appliances.

Conclusions:

The treatment with the Damon appliances resulted in a significantly greater increase of maxillary arch dimensions when compared to conventional appliances. Mandibular intercanine and interpremolar distances also presented greater increase in Damon than conventional appliances. The increase in mandibular arch length was greater in conventional than in Damon group.

Photoelastic analysis of stress distributions in the root-bone interface when applying various orthodontic methods to subside lower anterior crowding

Dental crowding is a prevalent problem in modern society. Various factors, including different bracket systems and geometry of wire, influence the outcome using superelastic wire in the alignment stage of treatment. Currently, the use of light round wire instead of large-sized rectangular wire is emphasized to avoid powerful torsional stiffness. However, these guidelines lack scientific evidence for support. They have been written predominantly based on clinical experience. Therefore, the purpose of this study was to evaluate how factors such as bracket systems and wire geometry affect the stress distribution at the root-bone interface. Models using a photoelastic material (PL-3) to simulate bone tissue were fabricated. The simulated teeth were arranged as in lower anterior crowding. Then, the crowded teeth were subjected to orthodontic treatment with various types of bracket, ligating approaches using ligature wires of different sizes, shapes, and materials. Photoelastic images of the bone area of the models were obtained and compared. The results showed that wire size plays a more significant role than the material or cross-sectional shape of the wire in affecting the stress distribution at the simulated root-bone interface. The teeth ligated with a larger cross-sectional diameter of wire showed the application of excessive torque, which may cause root resorption and slow down tooth movement. These results not only demonstrate the scientific evidence backing clinical experience but also can be a useful reference for further clinical application.

Stability comparison of two different dentoalveolar expansion treatment protocols

OBJECTIVE

The aim of this study was to compare the longitudinal stability of the conventional straight-wire system after the use of a quad-helix appliance with Damon self-ligating system in patients with Class I malocclusion.

METHODS

27 adolescent patients were evaluated at three different periods: pre-treatment (T1), post-treatment (T2) and three years post-treatment (T3). Group 1 included 12 patients (with a mean age of 14.65 year) treated with Damon 3MX bracket system; and Group 2 included 15 patients (with a mean age of 14.8 year) who underwent orthodontic treatment with Roth prescribed brackets after expansion with Quad-Helix appliance. Relapse was evaluated with dental cast examination and cephalometric radiograph tracings. Statistical analysis was performed with IBM-SPSS for Windows software, version 21 (SPSS Inc., Chicago, IL). A p-value smaller than 0.05 was considered statistically significant.

RESULTS

There were significant increases in all transverse dental and postero-anterior measurements (except for UL6-ML mm in Group 1) with active treatment. There was some significant relapse in the long-term in inter-canine width in both groups and in the inter-first premolar width in Group 2 (p< 0.05). Significant decrease in all frontal measurements from T2 to T3 was seen for both groups. Upper and lower incisors significantly proclined in T1-T2 (p< 0.05), however no relapse was found for both groups. When two systems were compared, there was no significant difference for the long-term follow-up period.

CONCLUSION

Conventional (quad-helix appliance with conventional brackets) and Damon systems were found similar with regard to the long-term incisor positions and transverse dimension changes of maxillary arch.

Early vertical correction of the deep curve of Spee

Even though few technological advancements have occurred in Orthodontics recently, the search for more efficient treatments continues. This paper analyses how to accelerate and improve one of the most arduous phases of orthodontic treatment, i.e., correction of the curve of Spee. The leveling of a deep curve of Spee can happen simultaneously with the alignment phase through a method called Early Vertical Correction (EVC). This technique uses two cantilevers affixed to the initial flexible archwire. This paper describes the force system produced by EVC and how to control its side effects. The EVC can reduce treatment time in malocclusions with deep curves of Spee, by combining two phases of the therapy, which clinicians ordinarily pursue sequentially.

Comparison of Changes in Incisors Position in Cases Treated with Damon Self-Ligating and Conventional Fixed Appliances

Objective:

This study aimed to compare the changes in maxillary and mandibular incisors position in cases treated with Damon self-ligating and conventional fixed appliances.

Methods:

The sample comprised 51 patients with Class I malocclusion, mild to moderate crowding, treated without extractions, divided into 2 groups: Group 1 consisted of 20 patients treated with Damon self-ligating appliance, with a mean initial age of 15.00 years, treated for a mean period of 2.01 years; and Group 2 comprised 31 patients treated with conventional fixed appliances, with a mean initial age of 14.98 years, treated for a mean period of 1.81 years. The initial and final cephalograms of each patient were measured. The intergroup comparisons were performed with independent t or Mann-Whitney tests.

Results:

Both groups showed a mild protrusion and a buccal inclination of the maxillary and mandibular incisors, with no statistically significant difference between them.

Conclusion:

The changes in maxillary and mandibular incisors position were similar between the groups treated with Damon self-ligating and conventional fixed appliances.

Accelerated orthodontic treatment - what's the evidence?

The demand and accessibility of orthodontic care has increased but has also been accompanied by patient requests for shorter treatment times. Longer orthodontic treatment increases the risk of decalcification, gingival recession, and root resorption and so shorter treatment times have multiple advantages as well as appealing to patient's desires. Numerous techniques and materials have been suggested to reduce treatment times but, in most cases, are based upon selected case reports with no prospective clinical trials to validate claims. The present review examines many of the current options purported to accelerate orthodontic tooth movement and the level of evidence presently available. There is some evidence to suggest that low-level laser therapy and a corticotomy involving the raising of a muco-periosteal flap are associated with accelerated orthodontic tooth movement; however, the current level of evidence is low to moderate in quality. For this reason, further research is required before routine application could be recommended.

Effectiveness and efficiency in clinical orthodontic practice

Proffitt et al. have described "effectiveness and efficiency" (E&E) as achieving desired results without wasting the orthodontist's and patients' time. In 1972, Archibald Cochrane published a monograph entitled "Effectiveness and Efficiency," which challenged the medical community to use medical protocols that were evidence-based. As a possible starting point for E&E, the orthodontist could consider an "Evidence-based clinical practice" (EBCP) model, which integrates the best research evidence with clinical expertise and patient values. This model considers scientific or evidence-based orthodontics (EBO) together with patient preferences and patient autonomy, clinical or patient circumstances, and clinical experience and judgment. In this paper, therefore, E&E will be discussed from an EBCP perspective which, for our purposes, includes relevant evidence but also our clinical experience and rationale. We will discuss: wire sequence; NiTi Wire types; space closure by sliding; canine retraction versus en masse retraction, 18" slot versus 22" slot, the Bidimensional System; self-ligating brackets (SL); vertical slot; economic aspects.

Assessment of the changes in arch perimeter and irregularity in the mandibular arch during initial alignment with the AcceleDent Aura appliance vs no appliance in adolescents: A single-blind randomized clinical trial

INTRODUCTION

The purpose of this 2-arm parallel trial was to assess the effects of the AcceleDent Aura (OrthoAccel Technologies, Houston, Tex) appliance on the increase in mandibular anterior arch perimeter, the reduction in mandibular arch irregularity, and the amount of discomfort during initial alignment of the mandibular arch with fixed appliances.

METHODS

Forty Class II adolescent patients with full fixed appliances and treated with maxillary premolar extractions and no extractions in the mandibular arch participated in this randomized clinical trial. They were recruited in a private practice and treated by 1 clinician. Randomization to either a no-appliance group or the AcceleDent Aura appliance group was accomplished with permuted blocks of 10 patients with the allocations concealed in opaque, sealed envelopes. Both the operator and the outcome assessor were blinded, but it was not feasible to blind the patients. Discomfort was recorded during the first week of treatment. Mandibular anterior arch perimeter and anterior irregularity were measured from plaster models taken at the start of treatment and after 5, 8, and 10 weeks.

RESULTS

No patients were lost to follow-up, and no data were missing. There was no difference in anterior arch perimeter at the start of treatment (P = 0.85; median, 0.6 mm; 95% confidence interval [CI], -1.6, +1.8 mm) or at any other time point (5 weeks: P = 0.84; median, -0.2 mm; 95% CI, -1.6, +1.2 mm; 8 weeks: P = 0.56; median, -0.3 mm; 95% CI, -1.6, +0.7 mm; 10 weeks: P = 0.67; median, -0.1 mm; 95% CI, -1.5, +1.1 mm). There was also no difference between groups for incisor irregularity (P = 0.46; median, -0.5 mm; 95% CI, -2.2, +2.8 mm; P = 0.80; median, 0.0 mm; 95% CI, -1.0, +1.1 mm; P = 0.70; median, 0.1 mm; 95% CI, -0.7, +0.8 mm; P = 0.65; median, 0.2 mm; 95% CI, -0.6, +0.6 mm). No difference was detected at any time during the first week for discomfort (baseline: P = 0.84; median, -1.5 mm; 95% CI, -15.9, +9.8 mm; 6 hours: P = 0.96; median, 0.3 mm; 95% CI, -23.5, +21.8 mm; 1 day: P, 0.75; median, -3.5 mm; 95% CI, -27.1, +26.9 mm; 3 days: P = 0.98; median, -0.6 mm; 95% CI, -20.6, +20.0; 7 days: P = 0.57; median, 0.5 mm; 95% CI, -5.0, +5.3 mm). However, significantly fewer participants in the AcceleDent Aura group used analgesics at day 1 (P = <0.01).

CONCLUSIONS

The AcceleDent Aura appliance had no effect compared with no appliance on increasing anterior arch perimeter, or reducing irregularity or perceived discomfort during initial alignment with fixed appliances, although more subjects used painkillers at 24 hours in the no-appliance group.

REGISTRATION

This trial was not registered.

PROTOCOL

The protocol was not published before trial commencement.

FUNDING

A special research grant was obtained from the Australian Society of Orthodontists Foundation for Research and Education to purchase the AcceleDent Aura appliances and fund the statistical analysis.