Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children

BACKGROUND

Prominent lower front teeth (Class III malocclusion) may be due to jaw or tooth position or both. The upper jaw (maxilla) can be too far back or the lower jaw (mandible) too far forward; the upper front teeth (incisors) may be tipped back or the lower front teeth tipped forwards. Orthodontic treatment uses different types of braces (appliances) fitted inside or outside the mouth (or both) and fixed to the teeth. A facemask is the most commonly reported non-surgical intervention used to correct Class III malocclusion. The facemask rests on the forehead and chin, and is connected to the upper teeth via an expansion appliance (known as 'rapid maxillary expansion' (RME)). Using elastic bands placed by the wearer, a force is applied to the top teeth and jaw to pull them forwards and downward. Some orthodontic interventions involve a surgical component; these go through the gum into the bone (e.g. miniplates). In severe cases, or if orthodontic treatment is unsuccessful, people may need jaw (orthognathic) surgery as adults. This review updates one published in 2013.

OBJECTIVES

To assess the effects of orthodontic treatment for prominent lower front teeth in children and adolescents.

SEARCH METHODS

An information specialist searched four bibliographic databases and two trial registries up to 16 January 2023. Review authors screened reference lists.

SELECTION CRITERIA

We looked for randomised controlled trials (RCTs) involving children and adolescents (16 years of age or under) randomised to receive orthodontic treatment to correct prominent lower front teeth (Class III malocclusion), or no (or delayed) treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcome was overjet (i.e. prominence of the lower front teeth); our secondary outcomes included ANB (A point, nasion, B point) angle (which measures the relative position of the maxilla to the mandible).

MAIN RESULTS

We identified 29 RCTs that randomised 1169 children (1102 analysed). The children were five to 13 years old at the start of treatment. Most studies measured outcomes directly after treatment; only one study provided long-term follow-up. All studies were at high risk of bias as participant and personnel blinding was not possible. Non-surgical orthodontic treatment versus untreated control We found moderate-certainty evidence that non-surgical orthodontic treatments provided a substantial improvement in overjet (mean difference (MD) 5.03 mm, 95% confidence interval (CI) 3.81 to 6.25; 4 studies, 184 participants) and ANB (MD 3.05°, 95% CI 2.40 to 3.71; 8 studies, 345 participants), compared to an untreated control group, when measured immediately after treatment. There was high heterogeneity in the analyses, but the effects were consistently in favour of the orthodontic treatment groups rather than the untreated control groups (studies tested facemask (with or without RME), chin cup, orthodontic removable traction appliance, tandem traction bow appliance, reverse Twin Block with lip pads and RME, Reverse Forsus and mandibular headgear). Longer-term outcomes were measured in only one study, which evaluated facemask. It presented low-certainty evidence that improvements in overjet and ANB were smaller at 3-year follow-up than just after treatment (overjet MD 2.5 mm, 95% CI 1.21 to 3.79; ANB MD 1.4°, 95% CI 0.43 to 2.37; 63 participants), and were not found at 6-year follow-up (overjet MD 1.30 mm, 95% CI -0.16 to 2.76; ANB MD 0.7°, 95% CI -0.74 to 2.14; 65 participants). In the same study, at the 6-year follow-up, clinicians made an assessment of whether surgical correction of participants' jaw position was likely to be needed in the future. A perceived need for surgical correction was observed more often in participants who had not received facemask treatment (odds ratio (OR) 3.34, 95% CI 1.21 to 9.24; 65 participants; low-certainty evidence). Surgical orthodontic treatment versus untreated control One study of 30 participants evaluated surgical miniplates, with facemask or Class III elastics, against no treatment, and found a substantial improvement in overjet (MD 7.96 mm, 95% CI 6.99 to 8.40) and ANB (MD 5.20°, 95% CI 4.48 to 5.92; 30 participants). However, the evidence was of low certainty, and there was no follow-up beyond the end of treatment. Facemask versus another non-surgical orthodontic treatment Eight studies compared facemask or modified facemask (with or without RME) to another non-surgical orthodontic treatment. Meta-analysis did not suggest that other treatments were superior; however, there was high heterogeneity, with mixed, uncertain findings (very low-certainty evidence). Facemask versus surgically-anchored appliance There may be no advantage of adding surgical anchorage to facemasks for ANB (MD -0.35, 95% CI -0.78 to 0.07; 4 studies, 143 participants; low-certainty evidence). The evidence for overjet was of very low certainty (MD -0.40 mm, 95% CI -1.30 to 0.50; 1 study, 43 participants). Facemask variations Adding RME to facemask treatment may have no additional benefit for ANB (MD -0.15°, 95% CI -0.94 to 0.64; 2 studies, 60 participants; low-certainty evidence). The evidence for overjet was of low certainty (MD 1.86 mm, 95% CI 0.39 to 3.33; 1 study, 31 participants). There may be no benefit in terms of effect on ANB of alternating rapid maxillary expansion and constriction compared to using expansion alone (MD -0.46°, 95% CI -1.03 to 0.10; 4 studies, 131 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Moderate-certainty evidence showed that non-surgical orthodontic treatments (which included facemask, reverse Twin Block, orthodontic removable traction appliance, chin cup, tandem traction bow appliance and mandibular headgear) improved the bite and jaw relationship immediately post-treatment. Low-certainty evidence showed surgical orthodontic treatments were also effective. One study measured longer-term outcomes and found that the benefit from facemask was reduced three years after treatment, and appeared to be lost by six years. However, participants receiving facemask treatment were judged by clinicians to be less likely to need jaw surgery in adulthood. We have low confidence in these findings and more studies are required to reach reliable conclusions. Orthodontic treatment for Class III malocclusion can be invasive, expensive and time-consuming, so future trials should include measurement of adverse effects and patient satisfaction, and should last long enough to evaluate whether orthodontic treatment in childhood avoids the need for jaw surgery in adulthood.

An In Vitro Study of the Abrasive Potential of Various Toothbrushes on the Surface of Aligner Attachments

Background Attachments play a vital role in aligner-led orthodontic therapy, first passively through retention of the appliance and secondly, through bringing about tooth movement, by virtue of its active surfaces, to achieve treatment goals. Additionally, irregularities on the surface of attachments attract plaque adhesion. Thus the effect of brushing with different toothbrushes on the surface of attachments is an important factor to study. This would allow clinicians to better advise patients who are undergoing aligner therapy. Four types of brushes are available commercially, namely hard, medium, soft, and ultra-soft. This study analyses the interaction between the kind of toothbrush used and the wear of the surface of the aligner attachment, to understand the impact of a toothbrush on the attachment. Aim To observe the surface wear and change in the shape of the aligner attachment on brushing with four varying hardness of toothbrush bristle (ultra-soft, soft, medium, and hard) over six months to three years. Material and methods One attachment was bonded to the buccal surface of extracted premolars. One tooth with attachment was subjected to SEM analysis and the rest were divided into four groups of five teeth each, based on the type of toothbrush to be used. Brushing with hard, medium, soft, and ultra-soft toothbrushes was carried out in a brushing simulator in two cycles simulating six months, one year, 18 months, and three years of brushing. A contact profilometer was used to evaluate surface roughness before and after brushing and pre- and post-surface roughness values were compared to quantitate changes after which SEM analysis was carried out for qualitative assessment of the surface of the samples. The Shapiro-Wilks test was applied to evaluate the normality of the data, followed by the one-way ANOVA, and statistical significance was applied at p<0.05. Results At six months, the samples brushed with the medium toothbrush showed the least surface roughness (0.2±0.192) and those brushed with the ultra-soft toothbrushes showed the highest surface roughness (1.9±0.159). At one year, the samples brushed with the soft toothbrush showed the least surface roughness (0.46 ±0.31) and those brushed with the ultra-soft toothbrushes showed the highest surface roughness (2.12 ±0.12). At the 1.5-year point, the surface roughness of the samples was lowest in the ultra-soft toothbrush group (0.43±0.39) and the highest in the soft toothbrush group (1.6± 0.41). At the three-year point, the surface roughness of the samples was lowest in the ultra-soft toothbrush group (0.28 ± 0.17) and the highest in the medium toothbrush group (1.6 ± 0.31). Conclusion Ultra-soft toothbrushes have a high abrasive potential, as seen by higher surface roughness values over six months and one year. Morphometric changes were the most noticeable for attachments brushed by hard-bristled toothbrushes and medium-bristled brushes.

Self-reported pain during different phases of orthodontic treatment with fixed appliance: A multi-centre randomized controlled trial in adolescents with crowding

OBJECTIVES

To compare self-reported pain levels across various treatment phases using passive self-ligating (Damon) and conventional (Victory) standardized fixed appliance systems.

MATERIALS AND METHODS

Adolescents (12-17 years old) with crowding and displaced teeth, planned for non-extraction treatment, were recruited from four orthodontic clinics. They were randomized into stratified blocks (1:1 ratio) using concealed allocation to receive Damon Q™ (34 boys, 28 girls) or Victory™ (39 boys, 31 girls). Pain and analgesic intake were assessed on seven different occasions with validated self-report questionnaires using a 10-grade scale.

RESULTS

Of the 132 patients included, six were lost to follow up. Clinically relevant mean pain scores (≥4) were registered in both groups after bonding upper and lower arches and after insertion of 0.019 × 0.025 stainless steel archwire. The highest mean scores were reported on day two after bonding the upper arch (Damon 5.96, Victory 7.18, P = .011). In both groups, at least 40% reported taking analgesics during various treatment phases. The Damon group reported a lower intake of analgesics on days one and two (P = .042 and .037) after treatment initiation. In the entire sample, boys reported significantly higher mean pain scores than girls on the second and third days after bonding (P = .008 and .026, respectively).

CONCLUSIONS

Lower pain levels were reported from the Damon group after bonding. In general, boys reported higher pain than girls did. Clinicians and adolescents need to be aware that clinically relevant pain levels can be expected not only after bonding but also in later phases.

Efficacy of microchips and 3D sensors for orthodontic force measurement: A systematic review of in vitro studies

OBJECTIVE

To evaluate the efficacy of microchips and 3D microsensors in the measurement of orthodontic forces.

METHODS

Through September 2023, comprehensive searches were conducted on PubMed/MEDLINE, SCOPUS and SCIELO without restrictions.

RESULTS

After removing duplicate entries and applying the eligibility criteria, 23 studies were included for analysis. All the studies were conducted in vitro, and slightly more than half of them were centred on evaluating orthodontic forces exerted by aligners. Eight utilized microchips as measurement tools, while the remaining studies made use of 3D microsensors for their assessments. In the context of fixed appliances, key findings included a high level of agreement in 3-dimensional orthodontic force detection between simulation results and actual applied forces. Incorporating critical force-moment combinations during smart bracket calibration reduced measurement errors for most components. Translational tooth movement revealed a moment-to-force ratio, aligning with the bracket's centre of resistance. The primary findings in relation to aligners revealed several significant factors affecting the forces exerted by them. Notably, the foil thickness and staging were found to have a considerable impact on these forces, with optimal force transmission occurring at a layer height of 150 μm. Furthermore, the type of material used in 3D-printing aligners influenced the force levels, with attachments proving effective in generating extrusive forces. Deliberate adjustments in aligner thickness were observed to alter the forces and moments generated.

CONCLUSIONS

Microchips and 3D sensors provide precise and quantitative measurements of orthodontic forces in in vitro studies, enabling accurate monitoring and control of tooth movement.

Assessment of patients' knowledge and preferences for the use of orthodontic aligners

OBJECTIVE

To evaluate the knowledge and preference of patients treated at a Dental School in Jaraguá do Sul, Brazil, about using aligners and the reasons for choosing this device as a treatment option.

DESIGN

A cross-sectional study.

PARTICIPANTS

A total of 82 participants aged 18-45 years recruited at a screening clinic.

METHODS

A questionnaire was completed in person using a tablet with digital forms.

RESULTS

Almost half of the participants (49%) knew about aligners; 40% were aged 18-24 years, and 77% were female. When observing the images of the types of orthodontic appliances, the aligners had an acceptance rate of 80%. Among the reasons that led to the preference for choosing aligners, 68% cited aesthetics and 42% comfort.

CONCLUSION

Recently, clear aligners have become a popular choice for orthodontic treatment, particularly among adults. Despite their popularity and effectiveness, many patients still need more information about aligner treatment. Over half of the respondents did not know what orthodontic aligners were. Younger participants had more knowledge about aligners than older participants. Patients still need more knowledge about the types of appliances available for orthodontic treatment. When presented with images of the kinds of devices available, almost 80% of participants showed greater satisfaction with aligners.

Comparison of the efficiency of initial dental alignment with Invisalign® aligners changed every 7 or 14 days in mature adults: Randomized clinical trial

OBJECTIVE

To compare the anterior crowding correction after sequential use of the first 5 aligners between two aligner exchange protocols (7 and 14 days) in mature adult patients.

MATERIALS AND METHODS

Thirty-six patients over 35 years who received orthodontic treatment with Invisalign® were randomly allocated to two different aligner replacement sequence protocols: Group 1: exchange every 7 days (n = 18); and Group 2: exchange every 14 days (n = 18). All patients were scanned with iTero Element 5D® (Align Technology) in two treatment times: at pre-treatment (T1) and after using the first five aligners (T2). Little's Irregularity Index (LII) and arch widths were evaluated with OrthoCAD software. Intra and intergroup comparisons were performed with the dependent and independent t-tests. The results were considered significant for P < .05.

RESULTS

Thirty-five patients completed the study. Both groups' maxillary and mandibular Irregularity Indexesi were significantly lower at T2. There was no significant difference in inter-canine, inter-premolar, and intermolar distances. G2 (14 days) presented a greater decrease in mandibular irregularity than G1 (7 days).

CONCLUSION

Both exchange protocols (7 and 14 days) effectively correct anterior crowding in the initial phase of orthodontic treatment with aligners in mature adult patients. However, the 14-day exchange protocol provided a greater correction in mandibular anterior crowding in the evaluated period than the 7-day exchange protocol.

An In Vivo Study to Compare the Clinical Effectiveness of Clear Retainer Made on a Conventional and a Digitally Fabricated Model Over a Six-Month Period After Debonding

Background With the advent of 3D printing, many more possibilities have arisen for treatment planning. 3D rapid prototyping has enabled us to see a whole other dimension that has helped us to give the best possible care for our patients. With more and more advancements being made in this subject, it becomes necessary to check the reliability of the equipment and its effectiveness in the management of the problem at hand. This original study was conducted with the aim of checking the accuracy, dimensional stability, and reliability of orthodontic retainers made on a conventional and digitally fabricated model over a six-month period after debonding. Material and methods The patients were selected from those who have completed fixed orthodontic mechanotherapy from the Department of Orthodontics and Dentofacial Orthopaedics, Sri Guru Ram Das Institute of Dental Sciences and Research, Sri Amritsar. Fifty patients received a clear retainer, which was fabricated for the upper and lower arch after removing the brackets. Patients were included in this study irrespective of their age groups. The manual method used a vacuum-forming machine to fabricate six retainers on stone models. In the digital method, new impressions were taken after three months, and digital models were obtained through 3D scanning and printing, followed by clear retainer fabrication. The data were gathered through a systematic process involving manual and digital methods for clear retainer fabrication and subsequent evaluation. The data obtained was computed for statistical evaluation and comparison. Results Mean and standard deviations of conventional (manual) and digital variables in the two groups were calculated. An ANOVA test was used to evaluate statistically significant differences for mesiodistal width and buccolingual width, and a post hoc Tuckey test was applied for multiple comparisons. The results indicated that most mesiodistal and buccolingual width measurements showed non-significant variations and exhibited a good correlation. Extraction space opening, assessed through an independent t-test for both the maxilla and mandible, also yielded non-significant and comparable results. Additionally, intra-operator and inter-operator measurements using a digital caliper demonstrated high agreement. Intra-class correlation (ICC) values exceeded 0.75, and inter-operator ICC results reflected a high level of agreement ranging from 0.8 to 0.99. Conclusion The primary objective of this study was to establish a correlation between the accuracy, dependability, and clinical efficacy of orthodontic retainers produced using both conventional and digitally created models. This investigation spanned a duration of six months following the removal of orthodontic brackets. The results showed that most of the statistically significant values were due to the inherent potential of the 3D printer for polymerization shrinkage, which, being a stereolithographic 3D printer, had a potential for a slight dimensional shift in the transverse dimension. However, the mean difference between all the models printed was slight and clinically insignificant.

Salivary microbiomes vary among orthodontic appliances and associate with clinical periodontal parameters

OBJECTIVE

To investigate the salivary bacterial communities during the first 6-month orthodontic treatment with Clear Aligners (CA) and Fixed Appliances (FA), and its correlation with clinical periodontal parameters.

MATERIALS AND METHODS

Saliva and periodontal parameters were sampled from individuals wearing CA or FA before treatment (T0), and after 3- (T3) and 6-month (T6) treatments. Salivary bacterial communities characterized based on the 16S rRNA V3-V4 region were compared between FA and CA and correlated with clinical periodontal parameters.

RESULTS

Probing Depth (PD) significantly increased at T6 in the FA group versus T0, whereas it remained stable in the CA group. The Shannon and Pielou indices were significantly higher in the FA group and significantly positively correlated with periodontal inflammation parameters. β-diversity analysis revealed distinct communities between the FA group and CA group at T6. The relative abundances of 3 genera and 15 species were significantly higher in the FA group. Among the above appliance-type related taxa, bacterial genera Selenomonas, Stomatobaculum, Olsenella and Faecalicoccus and bacterial species Selenomonas_sputigena, Dialister_invisus, Olsenella_profus, Prevotella_buccae, Cryptobacterium_curtum and Clostridium_spiroforme were significantly positively associated with periodontal parameters.

CONCLUSIONS

Orthodontic treatments trigger appliance-related salivary bacterial communities, highlighting the importance of developing appliance-orientated periodontal strategies during orthodontic treatments. Salivary bacterial communities harboured by patients wearing FA possess higher bacterial parameters which were associated with increasing PD, PI and Gingival Index.

Clear aligner therapy versus conventional brackets: Oral impacts over time

Background

The objective is to compare the impact of clear aligner treatment (CAT) versus conventional fixed appliance treatment (FAT) on oral health-related quality of life (OHRQoL) among adults at five-time points: pretreatment (T0), 1 week (T1), 1 month after (T2), and 6 months after (T3) treatment initiation, and in the long-term follow-up (T4).

Materials and Methods

Search terms were based on Medical Subject Headings (MeSH) and non-MeSH. Potentially eligible studies compared OHRQoL in clear aligner (CA) and fixed appliance (FA) patients. In February 2023, Scopus, Web of Science, Cochrane, and PubMed were searched for published studies. Nine out of 94 shortlisted papers were eligible for a systematic review. Of these nine papers, five studies were considered for a meta-analysis.

Results

At T0, CA and FA patients had similar oral health impact profile (OHIP)-14 questionnaire scores with a standard mean difference (SMD) of 0.105 (confidence interval [CI]: -1.029-1.48). The SMD of the OHRQoL related to T1, T2, and T3 was -3.119 (CI: -0.145, 0.355), -1.527 (CI: -5.597, -0.64), and - 2.331 (CI: -1.906, -1.148). T4 showed no difference between groups (SMD = 0.007, CI: CI: -4.286, -0.376). Regarding the OHIP-14 domains, functional limitations remained consistent in both groups across all time intervals. Psychological discomfort exhibited a notable difference only at T2. Throughout the treatment, CAT showed significantly lower levels of physical, psychological, and social disability, as well as handicap, though these differences did not persist beyond T4. Notably, physical pain was the sole domain that remained elevated in the FAT group up to T4.

Conclusion

During the 1st day of the orthodontic treatment, both the CA and FA groups had comparable OHRQoL statuses. However, as time passed, the CA group notably improved their OHRQoL compared to the FA group. Interestingly, after a year or the completion of treatment, both groups eventually reached similar OHRQoL levels. Nevertheless, it is worth noting that FA patients continued to experience more physical pain even a year later.

Finite element analysis of two skeletally anchored maxillary molar distalisation methods

OBJECTIVE

To compare two methods of maxillary molar distalisation with skeletal anchorage using finite element analysis (FEA).

METHODS

Two digitised models were created: the miniscrew-anchored distaliser, which consisted of a distalisation method anchored in a buccal miniscrew between the first molar and second premolar (Model 1), and the miniscrew-anchored palatal appliance, which consisted of a distalisation method anchored in a miniscrew on the anterior region of the palate (Model 2). FEA was used to simulate both methods, assessing teeth displacements and stress concentration.

RESULTS

The miniscrew-anchored distaliser showed greater buccal than distal displacement of the first molar, while the opposite was observed in the miniscrew-anchored palatal appliance. The second molar responded similarly in the transverse and anteroposterior perspectives with both appliances. Greater displacements were observed at crown level than in apical regions. Greater stress concentration was observed at the buccal and cervical regions of the crown in the miniscrew-anchored distaliser and the palatal and cervical regions in the palatal appliance. The stress progressively spread in the buccal side of the alveolar bone for the miniscrew-anchored distaliser and in the palatal root and alveolar bone for the palatal appliance.

CONCLUSION

FEA assumes that both appliances would promote maxillary molar distalisation. A skeletally anchored palatal distalisation force seems to provide a greater molar bodily movement with less undesirable effects. Greater stress is expected at the crown and cervical regions during distalisation, and the stress concentration in the roots and alveolar bone depends directly on the region the force was applied.

Vertical and sagittal changes produced by an expander with differential opening and fan-type expander: A post-hoc analysis of a randomised controlled trial

OBJECTIVE

To compare the sagittal and vertical cephalometric effects in participants treated with an expander with differential opening (EDO) versus the fan-type expander (FE).

DESIGN

Two-arm parallel randomised clinical trial (RCT).

METHODS

This study comprised cone-beam computed tomography-derived cephalometric images from 48 participants from a RCT. The sample was randomly allocated into two groups. The study was single-blinded. In total, 24 participants were treated with rapid maxillary expansion (RME) using EDO and 24 participants underwent RME using FE. The primary outcomes were the dentoskeletal vertical changes produced by RME. The secondary outcomes were the dentoskeletal sagittal changes. A cephalometric analysis was performed before treatment and 1 or 6 months after the active phase of RME using Dolphin Imaging Software. Intergroup comparisons of interphase changes were performed using the t-test and Mann-Whitney U test (P < 0.05).

RESULTS

The final sample comprised 24 patients (11 men, 13 women; mean age = 7.6 ± 0.9 years) in the EDO group and 24 patients (10 men, 14 women; mean age = 7.8 ± 0.9 years) in the FE group. Both expanders produced a similar clockwise rotation of the mandible (FMA; mean difference [MD] = 0.09°, 95% confidence interval [CI] = -1.01 to 0.84). In the FE group, a greater increase of the SNA angle was observed after expansion compared to the EDO group (MD = 1.04°, 95% CI = -1.90 to -1.58). A greater palatal torque of maxillary incisors was observed in the FE group (MD = 1.32°, 95% CI = 0.05-2.56). Of the participants, 54% reported a little discomfort during the active phase of treatment and 46% of the participants did not report any discomfort.

CONCLUSION

Both expanders produced similar vertical cephalometric changes. FEs caused slightly more maxillary anterior displacement after expansion with a compensatory palatal torque of the maxillary incisors compared to the EDOs. However, the amount of sagittal difference was not clinically relevant.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov, under the identifier NCT03705871.

Impact of Portraiture Photography on Orthodontic Treatment: A Systematic Review and Meta-Analysis

Due to the clear depiction of facial aesthetics and other craniofacial parameters, portraiture photography (PP) is becoming more and more necessary in modern clinical practice. The studies chosen for this review's inclusion looked at how PP affected the orthodontic treatment and diagnostic procedure on the subjects who were watched in the studies. Studies published within the last decade precisely from 2013 were searched for across major online databases after devising a proper search strategy. Multiple reviewers created a specific data extraction form that was used for the investigation, followed by the evaluation of bias and the variables found in each of the chosen papers. This form was meant for the assessment for various variables encountered in this study. According to the meta-analysis, using PP was related with a statistically significant decrease in the risk of orthodontic treatment and diagnostic modalities, with odds ratios (OR) of 0.52 with a 95% confidence interval (CI) of (0.28, 0.96), and a relative risk (RR) of 0.66 with a CI of (0.45, 0.96). In orthodontics, PP is an important tool that offers useful data for diagnosis, treatment planning, and tracking treatment success. To validate the results of studies like ours, a sizable evidence sample is required due to the limited number of trials that have been performed in this area.

The Use of Questionnaires in Pain Assessment during Orthodontic Treatments: A Narrative Review

Pain is a complex multidimensional feeling combined with sensorial and emotional features. The majority of patients undergoing orthodontic treatment report various degrees of pain, which is perceived as widely variable between individuals, even when the stimulus is the same. Orthodontic pain is considered the main cause of poor-quality outcomes, patients' dissatisfaction, and lack of collaboration up to the interruption of therapy. A deep understanding of pain and how it influences a patient's daily life is fundamental to establishing proper therapeutic procedures and obtaining the correct collaboration. Because of its multifaced and subjective nature, pain is a difficult dimension to measure. The use of questionnaires and their relative rating scales is actually considered the gold standard for pain assessment. Choosing the most appropriate instrument for recording self-reported pain depends on a patient's age and cognitive abilities. Although several such scales have been proposed, and a lot of them are applied, it remains uncertain which of these tools represents the standard and performs the most precise, universal, and predictable task. This review aims to give an overview of the aspects which describe pain, specifically the pain experienced during orthodontic treatment, the main tool to assess self-perceived pain in a better and more efficient way, the different indications for each of them, and their correlated advantages or disadvantages.

Evaluation of Orthodontic Treatment Method Preferences of Dentistry Students, Dentists and Orthodontic Residents

Objective

The aim of this study was to evaluate orthodontic treatment method preferences among dentistry students, dentists and orthodontic residents taking into account factors such as esthetics, advantage/disadvantage, cost and treatment duration.

Methods

The study was carried out on three groups: dentistry students (n=318), dentists (n=110) and orthodontic residents (n=98), and a 17-question survey was applied. Questionnaire forms included informational photos of conventional metal brackets (CMB), esthetic ceramic brackets (ECB), self-ligating brackets (SLB), clear aligner (CA), and lingual brackets (LB). The participants' preferences for orthodontic treatment methods were evaluated using chi-square analysis, not only between groups but also considering gender and income level.

Results

Regarding esthetics, dentists (41%) and orthodontic residents (78%) mostly preferred CA, while dentistry students mostly preferred LB (44%). With regard to advantage/disadvantage, dentistry students (31%) and dentists (39%) mostly preferred SLB, while orthodontic residents mostly preferred CA (55%). Regarding the success of the treatment, all three groups mostly preferred CMB. (respectively 50%; 47%; 72%). While CA was mostly preferred for short-term treatments in all three groups (respectively 40%; 71%; 88%), CMB was mostly preferred for long-term treatments (respectively 35%, 51%, 55%). Gender and income-level differences had little effect on orthodontic treatment method preferences.

Conclusion

Except for long-term treatments and treatment success, there was generally great interest in CA, especially among orthodontic residents. Ceramic brackets and LB were generally the least preferred treatment methods among dentistry students, dentists, and orthodontic residents.

Cytotoxicity of Metal Ions Released from NiTi and Stainless Steel Orthodontic Appliances, Part 1: Surface Morphology and Ion Release Variations

Despite numerous studies on ion release from orthodontic appliances, no clear conclusions can be drawn due to complex interrelations of multiple factors. Therefore, as the first part of a comprehensive investigation of cytotoxicity of eluted ions, the objective of this study was to analyze four parts of a fixed orthodontic appliance. Specifically, NiTi archwires and stainless steel (SS) brackets, bands, and ligatures were immersed in artificial saliva and studied for morphological and chemical changes after 3-, 7-, and 14-day immersion, using the SEM/EDX technique. Ion release profiles were analyzed for all eluted ions using inductively coupled plasma mass spectrometry (ICP-MS). The results demonstrated dissimilar surface morphologies among parts of the fixed appliance, due to variations in manufacturing processes. The onset of pitting corrosion was observed for the SS brackets and bands in the as-received state. Protective oxide layers were not observed on any of the parts, but adherent layers developed on SS brackets and ligatures during immersion. Salt precipitation, mainly KCl, was also observed. ICP-MS proved to be more sensitive than SEM/EDX and exhibited results undetected by SEM/EDX. Ion release was an order-of-magnitude higher for SS bands compared to other parts, which was attributed to manufacturing procedure (welding). Ion release did not correlate with surface roughness.

Impact of Orthodontic Appliances on Hiring Prospects in Saudi Arabia: A Cross-Sectional Study

This study provides valuable insights into the cosmetic impact of orthodontic appliances on job-hiring prospects in Saudi Arabia. Both ceramic braces and clear aligners are considered cosmetic corrective devices compared to traditional metallic braces. This survey-based, cross-sectional study used two models, one male, and one female. Four standardized smiling frontal photographs were taken for each model: one without any appliance and three with different orthodontic appliances (i.e., metal braces, ceramic braces, and clear aligners). The photographs of each model were shown to potential employers, followed by three questions for each photo to assess the employers' views on the applicants' professionalism, communication skills, and the likelihood of being hired. The survey was distributed via an electronic questionnaire to employers in Saudi Arabia, collecting feedback from 189 participants. The sample was collected from October 2022 to February 2023. The models' scores while wearing metal and ceramic bracket appliances were significantly lower than when the models were wearing clear aligners or were not wearing any appliance in each domain. In conclusion, orthodontic appliances have cosmetic implications that affect job-hiring prospects, with a higher chance of being hired if the candidate does not have an orthodontic appliance.

The efficacy of manual toothbrushes in patients with fixed orthodontic appliances: a randomized clinical trial

OBJECTIVE

This study aims to evaluate three types of manual toothbrushes [Cross action (CA), Flat trim (FT), and orthodontic type (OT)] in terms of efficacy in plaque removal in patients undergoing fixed orthodontic treatment.

BACKGROUND

Manual toothbrushes are an essential part of oral hygiene for primary prevention. Plaque control, however, can be influenced by a number of individual and material-related factors. Individual factors include the presence of fixed orthodontic appliances on tooth surfaces, such as brackets and bands, which create difficulties with oral hygiene and lead to plaque formation. The evidence for the effectiveness of advanced bristle designs (multilevel, criss-cross) of the manual toothbrush alone in removing plaque in patients undergoing orthodontic therapy is limited.

METHODS

The experiment followed the Consolidated Standards of Reporting Trials (CONSORT) guidelines. This was a three treatment, three-period crossover clinical trial with a single brushing exercise. Thirty subjects were randomized to one of the three treatment sequences of different bristle designs: (CA, FT, and OT). The primary outcome measure was the difference in the plaque scores (baseline minus post-brushing) at each study period, as determined by the Turesky-Modified Quigley-Hein Plaque Index.

RESULTS

Of the thirty-four subjects enrolled in the study, thirty of the subjects met the inclusion criteria and completed all three periods of the study. The mean age was 19.5 ± 1.52 years, with a range of 18-23 years. The differences between treatments in plaque score reduction after brushing were statistically significant (p-value < .001). The treatment differences were statistically significant (p-value < .001) favoring the FT toothbrush over the OT and CA types of toothbrush designs. On the contrary, the difference between the OT and CA types was not statistically significant.

CONCLUSIONS

Plaque was significantly removed by the conventional FT toothbrush after a single brushing compared to the OT and CA types.

Concept for the Treatment of Class III Anomalies with a Skeletally Anchored Appliance Fabricated in the CAD/CAM Process-The MIRA Appliance

OBJECTIVE

Intermaxillary elastics, anchored skeletally, represent a promising concept for treatment in adolescent patients with skeletal Class III anomalies. A challenge in existing concepts is the survival rate of the miniscrews in the mandible or the invasiveness of the bone anchors. A novel concept, the mandibular interradicular anchor (MIRA) appliance, for improving skeletal anchorage in the mandible, will be presented and discussed.

CLINICAL CASE

In a ten-year-old female patient with a moderate skeletal Class III, the novel MIRA concept, combined with maxillary protraction, was applied. This involved the use of a CAD/CAM-fabricated indirect skeletal anchorage appliance in the mandible, with interradicularly placed miniscrews distal to each canine (MIRA appliance), and a hybrid hyrax in the maxilla with paramedian placed miniscrews. The modified alt-RAMEC protocol involved an intermittent weekly activation for five weeks. Class III elastics were worn for a period of seven months. This was followed by alignment with a multi-bracket appliance.

DISCUSSION

The cephalometric analysis before and after therapy shows an improvement of the Wits value (+3.8 mm), SNA (+5°), and ANB (+3°). Dentally, a transversal postdevelopment in the maxilla (+4 mm) and a labial tip of the maxillary (+3.4°) and mandibular anterior teeth (+4.7°) with gap formation is observed.

CONCLUSION

The MIRA appliance represents a less invasive and esthetic alternative to the existing concepts, especially with two miniscrews in the mandible per side. In addition, MIRA can be selected for complex orthodontic tasks, such as molar uprighting and mesialization.

Effect of COVID-19 on orthodontic treatment/practice- A systematic review and meta-analysis

Coronavirus disease of 2019 (COVID-19), which has affected almost all medical professions, has had a significant negative influence on dental care. Additionally, non-urgent dental procedures were stopped during the epidemic in a number of countries. The purpose of this systematic review was to examine the impact of COVID-19 on individuals who had undergone or are currently having orthodontic treatment in any capacity during/after the pandemic's occurrence. After a thorough search of the online journals, a total of 634 documents were found, and 416 of the papers were initially chosen. The removal of 362 similar or duplicate publications that followed led to the initial availability of 54 separate papers. The final selection consisted of 23 documents, mostly in vitro investigations, cross-sectional studies, and comparative evaluations, which satisfied the necessary inclusion and exclusion criteria. COVID-19 had a significant impact on nearly every sphere of the patients' lives who were undergoing orthodontic treatment. However, people who are currently availing of various orthodontic treatment modalities did not experience the same issues as the ones faced by patients earlier. Teleorthodontics emerged as a viable option to access treatment during the lockdown period caused due to the pandemic. COVID-19 also had an overall negative impact on the psyche and morale of orthodontists around the world. PROSPERO Registration Number: CRD42022380823.

Orthodontic treatment need, the types of brackets and the oral health-related quality of life

BACKGROUND

Malocclusion can affect the oral health-related quality of life (OHRQoL). The influence of the orthodontic treatment need (OTN) and the type of brackets on OHRQOL is not clear.

OBJECTIVES

The aim of the present study was to determine the relationships between OTN and the bracket type and OHRQoL during the first 6 months of orthodontic treatment (OT) in adult patients.

MATERIAL AND METHODS

This cohort study was conducted at the Department of Orthodontics of a private university. A total of 216 patients aged ≥18 years participated in the study (106 patients with conventional brackets and 110 with self-ligating brackets). The OHRQoL was evaluated using the 14-item Oral Health Impact Profile (OHIP-14) at 5 time points - before OT (T0), and at 24/48 h (T1), 1 month (T2), 3 months (T3), and 6 months (T4) after the installation of the orthodontic appliance. The OTN was evaluated with the dental aesthetic index (DAI) by 2 previously calibrated operators. For the statistical analysis, the χ2 test and the Mann-Whitney U test were used. Additionally, Poisson regression models were performed.

RESULTS

The evidence of an association between OHRQoL and OTN was found only at T3 (p = 0.0095). No association was found between OHRQoL and the bracket type. However, in the regression models, OHRQoL was statistically significantly worse at T3 in the group with a greater OTN (IRR (incidence rate ratio) = 1.34; 95% CI (confidence interval): 1.21;1.48) and at T4 in the self-ligation group (IRR = 1.23; 95% CI: 1.12;1.36).

CONCLUSIONS

The OHRQoL was affected in the same way at the beginning of OT, regardless of OTN and the bracket type used. However, a worse OHRQoL was observed at 3 months in subjects with greater OTN and at 6 months in patients with self-ligating brackets.

Comparative study of changes in the airway dimensions following the treatment of Class II malocclusion patients with the twin-block and Seifi appliances

BACKGROUND

Functional appliances are frequently used to stimulate mandibular growth in cases of Class II malocclusion with mandibular deficiency. Many studies have reported improved pharyngeal airway passage (PAP) dimensions following functional appliance therapy in children.

OBJECTIVES

The present study aimed to assess changes in the airway dimensions following the treatment of Class II malocclusion patients with the twin-block and Seifi appliances.

MATERIAL AND METHODS

Lateral cephalograms of 37 patients with Class II malocclusion and mandibular deficiency treated with the twin-block appliance (n = 20) or the Seifi appliance (n = 17) were assessed in this before-and-after study. The preoperative and postoperative lateral cephalograms were compared to determine changes in the airway dimensions at the level of the palatal plane (PP), the occlusal plane (OP) and the 2nd-4th cervical vertebrae (C2-C4) in the 2 groups. The results were analyzed with the t test and the one-way analysis of covariance (ANCOVA).

RESULTS

After treatment, significant changes occurred in the point A-nasion-point B (ANB) and sellanasion-point B (SNB) skeletal cephalometric indices in the twin-block appliance group, and in ANB, SNB and incisor-mandibular plane angle (IMPA) in the Seifi appliance group. The airway dimensions at the level of PP, OP and the 3rd cervical vertebra (C3) significantly increased postoperatively as compared to the baseline in the twin-block appliance group (p < 0.05). The increases in the airway dimensions at the level of PP and C3 in the twin-block appliance group were significantly greater than in the Seifi appliance group (p < 0.05).

CONCLUSIONS

The treatment of Class II Division I malocclusion with the twin-block appliance significantly increased the airway dimensions at the level of PP, OP and C3, whereas the Seifi appliance did not cause any significant changes in the airway dimensions.

Role of craniofacial phenotypes in the response to oral appliance therapy for obstructive sleep apnea

BACKGROUND

Mandibular advancement device (MAD) is a good alternative for patients with obstructive sleep apnea (OSA). However, the treatment response varies amongst individuals.

OBJECTIVE

This study aimed to explore the role of craniofacial features in the response to MADs to improve prognostication and patient selection.

METHODS

The retrospective trial contained 42 males aged 41.5 ± 9.0 years, and with an apnea-hypopnea index (AHI) of 21.5 ± 13.8 events/h. According to the mandibular plane angle, participants were divided into three groups: low angle (n = 13), average angle (n = 14) and high angle (n = 15). Under the monitoring of home sleep testing, adjustable MADs were used to titrate the mandible forward from 0 mm with an increment of 0.5 mm every day. The polysomnography outcomes, mandibular protrusion amounts, changes in upper airway MRI measurements and nasal resistance were compared amongst the three groups.

RESULTS

The normalisation rate (AHI <5 /h) was 92.3%, 57.1% and 46.7%, respectively, in the low-, average- and high-angle groups (p = .027). The effective protrusion where AHI was reduced by half was 20 (11.3 ~ 37.5) %, 31.3 (23.6 ~ 50) % and 50 (36.9 ~ 64.9) % of the maximal mandibular protrusion, in the low-, average- and high-angle groups (p = .004). Multivariate logistic regression revealed that increased gonion angle (OR = 0.878) and baseline AHI(OR = 0.868) can reduce the probability of normalisation.

CONCLUSION

The high mandibular plane angle might be an unfavourable factor to MAD treatment and more protrusion was needed to achieve a 50% reduction in AHI. Vertical craniofacial pattern (gonion angle) and baseline AHI constituted the model for predicting the effect of MADs.

Comparative Evaluation of Three Probiotics for Streptococcus mutans Prevention in Plaque Around Orthodontic Braces

BACKGROUND AND AIM

Orthodontic brackets can be a significant factor in enamel demineralization due to their complex structure, which makes brushing the teeth difficult and promotes the accumulation of food particles and dental plaque. The fact that metal braces have the highest surface tension and are more likely to cause enamel demineralization, which can result in the development of white spot lesions and enamel caries, is of critical significance to doctors, dentists, and patients. Probiotics have a beneficial effect in preventing and treating oral infectious diseases like tooth decay, gingival disorders, and bad breath. Research has shown that taking probiotics lowers the amount of Streptococcus mutans in the body. There has not been much research done to examine the results of administering a probiotic medication locally. This study was conducted to examine the effectiveness of three separate probiotics in the prevention of S. mutans accumulation in plaque surrounding orthodontic braces.

MATERIALS AND METHODS

A randomized controlled trial was conducted. The volunteers for each group were chosen using a straightforward random method. The sample size was 160 empirically determined subjects. They were divided as follows: study group 1 received probiotic lozenges (n=40). Study group 2 received probiotic sachets (n=40). Study group 3 received probiotic beverages (n=40). Group 4 was the control group, those who did not get probiotics (n=40). The samples were then plated onto culture media to test for Streptococcus mutans. S. mutans colonies were counted using a computerized colony counter.

RESULTS

The mean values of colony forming units (CFU/mL) of S. mutans at baseline in the control group were 354±23.6, while they were 232±41.7 at the end of the observation duration. The difference was non-relevant statistically (p=0.793). The mean values of CFU/mL of S. mutans at baseline in the group taking probiotic lozenges were 358.7±39.93, while they were 57±10.12 at the end of the observation duration. The difference was relevant statistically (p=0.021). The mean values of CFU/mL of S. mutans at baseline in the group taking probiotic sachets were 321.36±41.67, while they were 215.5±22.66 at the end of the observation duration. The difference was relevant statistically (p=0.043). The mean values of CFU/mL of S. mutans at baseline in the group taking the probiotic drink were 335.76±40.12, while they were 75.1±28.74 at the end of the observation duration. The difference was relevant statistically (p=0.032).

CONCLUSION

There was a significant decline in the number of colonies of S. mutans in all three forms of probiotics; however, the decline was greatest in the study participants taking probiotic lozenges.

Efficacy and Accuracy of Maxillary Arch Expansion with Clear Aligner Treatment

The aim of this work was to evaluate the efficacy and accuracy of maxillary arch transverse expansion using the Invisalign^® clear aligner system without auxiliaries other than Invisalign attachments. Knowing the accuracy of a movement through a clear aligner system allows the clinician to plan the treatment with greater precision and to achieve the expected result faster. The study group included 28 patients with a mean age of 17 ± 3.2 years. The treatment protocol for all the selected patients included the application of the Invisalign^® clear aligner system without auxiliaries, except for the Invisalign^® attachments; in no case were tooth extraction or interproximal enamel reduction (IPR) performed. Linear measurements of the expansion were assessed before treatment (T0), at the end of treatment (T1), and on final virtual models by ClinCheck^® (TC). A paired t-test was used to compare T0-T1 and T1-TC differences. A paired t-test was applied, and one normality was validated with the Shapiro-Wilks test. If normality was not met, the nonparametric test (Mann-Whitney U test) was applied. The level of significance was set at 5%. Statistically significant differences were found for all measurements at T0-T1. The results showed an average accuracy of efficacy of 70.88%. The differences in predictability between the various vestibular measurements (intercanine, inter-premolar, and intermolar) were not statistically significant, while they were for gingival measurements. The overall accuracy of the expansion treatment was 70%, regardless of tooth type.

Comparison of the Accuracy of Two Transfer Caps in Positional Transmission of Palatal Temporary Anchorage Devices: An In Vitro Study

The aim of this study was to compare the positional information transfer accuracy of palatal temporary anchorage devices (TADs) of two different brands of transfer caps: PSM and Leone. Thirty plaster casts of maxillary dental arches were chosen for master models. A couple of Leone TADs were inserted in each master model. For each master model, two analysis models were created: using two transfer caps, Leone and PSM, the impressions were taken, the analogues were connected on the transfer caps, and the casts were poured. Using digital methods and equipment, such as a 3D scanner, a 3D analysis and a comparison of the accuracy of the two transfer caps in transferring the positional information of the TADs was then made. The data obtained were analyzed using the Mann-Whitney U-test at a significance level of α = 0.05. PSM transfer caps showed higher error frequency in almost all measurements. Only two measurements had a larger error in the analysis models made with Leone transfer caps. The Mann-Whitney U-test found a significant difference between the error levels of TADs found in the analysis models created with PSM transfer caps. Leone transfer caps showed greater reliability in TADs positional information transmission.

Evaluation of the stability of treatment with Herbst appliance associated with Hyrax expander and fixed orthodontics through counterpart analysis: A longitudinal follow-up study

OBJECTIVE

The aim of this study was to evaluate the stability of treatment with a Herbst appliance associated with Hyrax expander (Stage I), followed by fixed appliances (Stage II) and follow-up for an average of 4 years after Stage II, on dentoskeletal facial structures.

METHODS

This study involved 50 adolescents with Angle Class II division 1 malocclusion associated with mandibular retrognathism: Treated Group (TG-25) and Control Group (CG-25). Lateral cephalometric radiographs were taken: T1, immediately before Stage I (TG) or at the beginning of the follow-up period (CG); T2, at the end of Stage I (TG) or the follow-up period (CG); T3, at the end of Stage II (TG); and T4, on average, 4 years after Stage II (TG). Enlow's counterpart analysis and some cephalometric measurements were evaluated. Parametric and non-parametric tests were used (P ≤ 0.05).

RESULTS

The ramus alignment variables (P < 0.001), SNB (0.040), ANB (<0.001), 1.PP (P = 0.015), 1.MP (P < 0.001), ms/RLp (P < 0.001), mi/RLp (P < 0.001) and S-LS (P = 0.005) showed differences between TG and CG from T1 to T2. Longitudinally, there were differences in ramus alignment, P = 0.003, T1 > T2 < T3 = T4; SNB, P = 0.016, T1 < T2 = T3 = T4; ANB, P < 0.001, T1 > T2 = T3 = T4; 1.MP, P < 0.001, T1 < T2 = T3 = T4; ms/RLp, P = 0.002, T1 = T2 < T3 = T4; mi/RLp, P < 0.001, T1 < T2 = T3 = T4; S-LS, P < 0.001, T1 > T2 = T3 = T4 and S-LI, P = 0.003, T1 = T2 = T3 > T4.

CONCLUSION

The nasomaxillary complex (MCF/PM alignment) tended to a retrusive effect to compensate the degree of mandibular retrusion. The protrusive effect of the lower facial third was evident after the Herbst stage and did not remain stable in the follow-up. The dentoalveolar compensation and improvement in facial profile remained stable.

Antibacterial and Physical Properties of PVM/MA Copolymer- Incorporated Polymethyl Methacrylate as a Novel Antimicrobial Acrylic Resin Material

Polymethyl methacrylate (PMMA), an acrylic resin used in orthodontic appliances and removable dentures for its biocompatibility and esthetics, may harbor bacteria on its surface. The present study investigated a new PMMA formula with Gantrez: an antibacterial copolymer of methyl vinyl ether and maleic acid (PVM/MA). Samples were tested for mechanical properties (surface hardness, flexural strength, water sorption, and water solubility) and effects against Streptococcus mutans. Six groups (0%-control, 5%, 10%, 15%, 20%, and 25% Gantrez) of n = 12 were fabricated for physical property tests and analyzed with one-way ANOVA and Prism 6. From these results, three groups (0%, 5%, and 10% Gantrez) were selected for antibacterial tests, and data were analyzed with one-way ANOVA and Tukey’s multiple comparison test. Adding 5% and 10% Gantrez into PMMA significantly decreased S. mutans adhesion. There was no significant difference between the control vs. 5%, 10%, 15%, and 20% Gantrez (p > 0.05) for surface hardness, the control vs. 5% Gantrez (p > 0.05) for flexural strength, and the control vs. 5 and 10% Gantrez for water sorption and water solubility. Overall, incorporating 5% Gantrez into PMMA may be a promising solution to reduce bacterial adhesion without changing the acrylic resin’s physical properties.

Awareness on three-dimensional printing of orthodontic appliances among dental students

The aim of the study was to evaluate the knowledge and awareness regarding the use of three-dimensional (3D)-printed appliances used in orthodontics among students pursuing dentistry. The distribution of the questionnaire was done using an online Google Forms link to about 100 dental students. The questionnaire compromised questions that were designed for assessing the various findings and knowledge of update, and finally, questions related to facts on various 3D-printing appliances. Among the total population, 58% of the population are aware of 3D printing used for various dental applications, whereas 42% of the population are not aware of the same. Among the total population, 58% of the population are aware of 3D printing used in dentistry, whereas 42% of the population are not aware of 3D printing used in dentistry. Inside the limits of the review, it very well may be inferred that 3D-printed machines have a rising use in the majority of the dental fields and understudies chasing after dentistry know about it. The knowledge about the basic and fundamental working and the usage of such appliances is developing among undergraduate students. Further continuing education programs can be provided to improve the same.

Debonding of orthodontic appliance changes salivary physicochemical properties and favors regression of active caries lesions: A 13-week follow-up study

AIM

This prospective cohort study aimed to investigate whether orthodontic appliance removal (OAR) combined with caries-preventive strategies and fluoride varnish treatments alters salivary physicochemical properties, changes the activity of carbonic anhydrase VI (CA VI_ACT ) and α-amylase (α-AML_ACT ), and favors the regression of active caries lesions (ACL).

DESIGN

Twenty-two individuals aged between 13 and 24 years were assessed for the presence of visible biofilm, daily sugar exposure, caries activity, salivary flow rate (SFR), pH, buffering capacity (BC), and CA VI_ACT and α-AML_ACT activity at baseline, and 1, 5, and 13 weeks after OAR. Variables were assessed using repeated-measures analysis of variance, Cochran's Q and McNemar's test, and Pearson's correlation.

RESULTS

We observed a significant decrease in the number of ACL at the 5-week (29% reduction) and 13-week follow-ups (58% reduction). At the 5- and 13-week follow-ups, the percentage of visible biofilm and sugar exposure decreased, whereas the salivary pH and α-AML_ACT activity significantly increased. BC and CA VI_ACT remained unchanged throughout the follow-up.

CONCLUSION

OAR combined with caries-preventive strategies and fluoride varnish treatments favored the regression of ACL and increased salivary pH and α-AML_ACT activity, whereas BC and CA VI_ACT remained stable.

A Scoping Review about the Characteristics and Success-Failure Rates of Temporary Anchorage Devices in Orthodontics

This study synthesized the scientific evidence concerning the main characteristics of the Temporary Anchorage Devices (TADs) used in orthodontics and reported the success-failure rates during treatment. For that means, this scoping review collected articles from previous research. A complementary search was carried out in the databases PubMed-MEDLINE, Scopus, LILACS, and EMBASE, focusing on original studies published from 2010 to 2020. We analyzed the main characteristics of the publications. As a result, 103 articles were included. Most of the research was conducted among different groups, who needed TADs principally in the maxilla and an interradicular location between the second premolar and first molar. AbsoAnchor, Dentos Inc., Daegu, Korea, was the most used brand of TADs. The most common characteristics of the devices and biomechanics were a diameter and length of 1.6 mm and 8 mm, a self-drilled system, a closed technique for placement, immediate loading, and forces that ranged between 40 and 800 g. Of the studies, 47.6% showed success rates ≥90%. In conclusion, high success rates were found for TADs, and differences were found according to sociodemographic and clinical variables. The studies showed variability in methodological design, and scientific publications were concentrated in certain countries. We recommend further scientific research on TADs using more standardized designs.

Minimal Important Difference of the Psychosocial Impact of Dental Aesthetics Questionnaire Following Orthodontic Treatment: A Cohort Study

(1) This study aimed to do a longitudinal validation of the psychosocial impact of dental aesthetics questionnaire (PIDAQ) and determine its minimal important difference (MID) following orthodontic treatment; (2) 42 adolescents (11 to 18 years old) were recruited for treatment with fixed appliances and the participants answered the Malaysian PIDAQ prior to treatment (T0), mid-treatment (T1), and post-treatment (T2), plus a global health transition scale at T1 and T2. Data analyses included repeated measures ANOVA and paired sample t-tests. Test–retest was administered 2 to 6 weeks from T0; (3) The final sample comprised 37 subjects (response rate = 88.1%). The 95% limits of agreement were −10.3 to 8.5 points. In the anchor-based approach, those who experienced the smallest changes by reporting their dental aesthetics as “a little improved” had an insignificant PIDAQ score change of −5.3 at T1. At T2, the PIDAQ scores of those in this category were reduced significantly (mean change = −26.2; effect size (ES) = 1.0; p = 0.34). In the distribution-based approach, standardized PIDAQ scores were significantly reduced, with medium (0.7) to large (1.5) ES at T1 and T2, respectively; (4) The PIDAQ can detect orthodontic-related changes in patients’ psychosocial well-being. The post-treatment MID is 26 scale points with large ES.

Cephalometric evaluation of the cervical spine posture following fixed functional therapy with Forsus™ appliance

BACKGROUND

To investigate whether fixed functional therapy for mandibular advancement with the Forsus™ appliance would produce any changes in the cervical spine posture.

MATERIALS AND METHODS

This prospective clinical exploratory study was conducted on 12 patients (six females and six males) with a mean age of 15 ± 1.3 years, having mandibular retrusion, Class II malocclusion, who were treated with the Forsus™ appliance. Lateral cephalogram was taken twice, once at the baseline (T1) before the commencement of the treatment and once following termination of fixed functional treatment (T2). Eleven measurements representing the vertical and the sagittal craniofacial proportions, and the head posture, were taken into account. Data were analyzed using SPSS version 22. The variations between before and after treatment measurements were collated using paired t-test. P < 0.05 was considered statistically significant.

RESULTS

No significant differences were noticed in the angle linking the horizontal lines of the head and the superior crest of the spinal column before and after the treatment, with P = 0.73. The cervical curvature angle also failed to show any significant difference with P = 0.14.

CONCLUSION

Fixed functional therapy with the Forsus™ device resulted in dentoalveolar and soft tissue alterations alone but did not alter the cervical spine posture.

[Clinical and laboratory studies of light-curing base material for the manufacture of intraoral orthodontic devices]

OBJECTIVE

To study the physical and mechanical properties of the new basic light polymer material in clinical conditions in pediatric orthodontic patients.

MATERIAL AND METHODS

The strength properties of 113 basic orthodontic devices made of photopolymer material without reinforcement with a screw, vestibular arch, and clasps t (55 devices, 30 of them for the upper jaw, 25 for the lower jaw) and with quartz mesh reinforcement of the base (58 devices: 30 for the upper jaw, 28 for the lower jaw) were studied in 60 children aged 3 to 12 years in the periods of temporary and removable bite.

RESULTS

In total, breakdowns of the base in devices without reinforcement were noted in 5.5% of cases. Our experimental studies have shown a significant improvement in the strength properties (modulus of elasticity, crack resistance, bending strength, maximum bending strain) when reinforcing the base polymer quartz mesh more than times. The clinical part of the study effectively reflects the positive trends in the reinforcement of the base from. A specific symptom complex of allergic reactions when wearing removable devices made of light-curing polymer was not detected. The observations continued for two years.

CONCLUSION

The obtained results of the strength properties of the reinforced base from the light-cured polymer and the absence of breakdowns, cracks and other deformations make it possible to produce reliable extensible orthodontic removable structures and devices, as well as to recommend this bioinert material for the correction of dental anomalies in children in the clinic of an orthodontist. This will improve the quality of services provided, significantly reduce the time of orthodontic treatment of dental anomalies in children.

Effect of fixed orthodontic appliances on self-assessment and diagnosis of halitosis in undergraduate dental students

Background:

The effects of fixed orthodontic therapy on the occurrence of halitosis are not yet fully understood. This study aimed to evaluate the effect of fixed orthodontic appliances on self-assessment and diagnosis of halitosis in undergraduate dental students.

Materials and Methods:

Sixty-two undergraduate dental students were included in this cross-sectional study. Two groups (n = 31 per group) were composed of participants with (study group) or without (control group) fixed orthodontic appliance. Halitosis self-assessment and clinical diagnosis were assessed using a visual analogic scale (VAS) and sulfur volatile compounds (SVCs) assessment, respectively. The subjective (VAS) and objective (SVC) malodor assessments were classified in absence, light, moderate, or severe malodor. Chi-square Pearson test and Spearman's correlation were applied for data analysis, with a significance level of 5%.

Results:

The use of fixed orthodontic appliances had no effect on self-assessment (P = 0.490) or clinical diagnosis (P = 0.610) of halitosis. Self-assessment was not significantly associated with the diagnosis of halitosis regardless the use of fixed orthodontic appliance (P ≥ 0.737). Male participants showed higher diagnosis of halitosis (P = 0.007). SVC measurements showed the absence of halitosis in 51.6% and 58.1% of participants with or without orthodontic appliances, respectively.

Conclusion:

The use of fixed orthodontic appliances affected the self-assessment of halitosis but no SVC measurements. It was not verified a correlation between subjective and objective methods to diagnose halitosis in dental students.

Comparative analysis of growth factors and chemokine secretions between conventional lingual and labial fixed orthodontic appliances

Background

Orthodontic appliances elicit the secretions of some cytokines, chemokines, and growth factors which further have some significances in the remodeling of periodontium tissues. The significant differential forces applied on the periodontium by different types of orthodontic appliances. The secretion of these factors is indirectly responsible for the proper resorption of bones of the periodontal region through molecular signaling, which further supports to facilitate organized movement of the teeth. Objective: In the present study, we carried out the assessment and comparative analysis of the growth factors and chemokines present in the saliva samples of the human subjects of orthodontic treatment with two different treatment modalities: conventional lingual and labial fixed orthodontic appliances.

Materials and Methods

Total 40 saliva samples were collected of which 20 subjects were treated with the conventional lingual appliances and 20 subjects with the labial fixed appliances. All the salivary samples were acquired from the subjects after 21 days treatment. Cytometric bead array was performed to assess the growth factors and chemokines in the saliva on the flow cytometer.

Results

No significant differences were seen in the growth factor secretion in the saliva of both types of subjects. The same trend was observed for the chemokine secretion in the saliva except CXCL8, CCL11, CCL2, CCL5, and CXCL9.

Conclusion

The similarity in chemokine and growth factor profile between labial and lingual fixed orthodontic appliances indicates that their molecular mechanisms and overall effect on the periodontium are analogous.

Role of Essential Oil-Based Mouthwashes in Controlling Gingivitis in Patients Undergoing Fixed Orthodontic Treatment. A Review of Clinical Trials

Essential oil (EO)-based mouthwashes have been used for oral health maintenance due to their antimicrobial and anti-inflammatory properties. The aim was to review clinical trials that assessed the role of EO-based mouthwashes in controlling gingivitis in patients undergoing fixed orthodontic treatment (OT). The Patients, Interventions, Control and Outcome (PICO) format was based on the following: (a) P: Patients undergoing fixed OT (b) Intervention: EO-based mouth-wash; Control: Mouthwashes that did not contain EOs or no mouthwash (d) Outcome: Control of gingivitis measured by clinical indices. Databases were searched manually and electronically up to and including May 2021 using different medical subject subheadings. Data screening and extraction were performed. The risk of bias within randomized controlled trials was assessed using the revised Cochrane Collaboration’s risk of bias tool (RoB 2). The Risk of Bias In Non-randomized Studies—of Interventions (ROBINS-I) tool was used for non-randomized controlled trials. Disagreements related to literature search and RoB evaluations were resolved via discussion. Six clinical studies were included. Four studies showed that Listerine^® is effective in controlling gingivitis in patients undergoing fixed OT. One study reported that the use of 5% Fructus mume mouthwash resulted in a significant reduction in gingival bleeding. Two mouthwashes that contained 1% Matricaria chamomilla L. and 0.5% Zingiber officinale were also found to be efficient in controlling gingival bleeding. Four, one and one studies had a low, moderate and high RoB, respectively. In conclusion, EO-based mouthwashes seem to be effective for the management of gingivitis among patients undergoing fixed OT. Further well-designed and power-adjusted clinical trials are needed.

3D Morphometric Analysis of Human Primary Second Molar Crowns and Its Implications on Interceptive Orthodontics

The second primary molar represents an anchorage element in interceptive orthodontics. The present study aims to analyze the 3D morphology of primary second molars in order to provide reference data and implications about the development of orthodontic bands for second primary molars. Digital models of dental arches from 150 subjects in primary or mixed dentition were analyzed. Six dimensional variables were digitally measured for each second primary molar, and the mean and standard error of the mean (SEM) were calculated and compared applying Student t-test statistical analysis. The mean value results show statistically significant dimensional differences between the upper and lower teeth, (mostly p < 0.0001), except for the variable h1, while only the variable h1 showed significant differences between the antimetric teeth (left and right). The dimensional variations between the right and left molars were considerably minor compared to those found by comparing the upper and lower arches. A significantly higher dimension of the lower molars and a more rectangular shape were observed.

Effectiveness of orthodontic toothbrush versus conventional toothbrush on plaque and gingival index reduction: A systematic review and meta-analysis

OBJECTIVE

In orthodontic patients submitted to oral hygiene instruction, what is the efficacy of orthodontic toothbrush (O-TB) versus conventional toothbrush (C-TB) on plaque and gingival index reduction in randomized and non-randomized controlled clinical trials?

METHODS

Electronic database search was performed on PubMed, ClinicalTrials.gov, Cochrane Library and Google Scholar. Database research, study selection, data extraction and ROBINS-I and Risk of Bias Tool 2.0 analysis were conducted by two independently examiners in duplicate. Two different meta-analyses were performed for plaque index and gingival index, followed by the analysis of overall quality of the evidence using GRADE.

RESULTS

A total of 158 studies were identified for screening; six articles were included in qualitative synthesis, and of those, three were subjected to a quantitative synthesis (meta-analysis). Three non-randomized studies presented an overall 'low', 'moderate' and 'high' risk of bias for each one of the articles, and the three randomized clinical trials presented 'low risk' for two articles and 'some concerns' quality for the other one. The overall strength of evidence was ranked 'very low' quality for plaque index and gingival index subgroups.

CONCLUSIONS

Gingival bleeding is not modified by orthodontic design toothbrush, but there is circumstantial scientific evidence for recommending the use of an O-TB instead a C-TB based on the analysis of plaque index control. Although major plaque removal of the O-TB was validated by meta-analysis, this improvement is not completely clarified which calls for further clinical studies to assess the effects of using an O-TB compared with a C-TB.

Medical Device Regulation: Requirements for Dental Professionals Who Prescribe and Manufacture Custom-Made Devices

A custom-made device (CMD) is a medical device intended for the sole use of a particular patient. In a dental setting, CMDs include prosthodontic devices, orthodontic appliances, bruxism splints, speech prostheses and devices for the treatment of obstructive sleep apnoea, trauma prevention and orthognathic surgery facilitation (arch bars and interocclusal wafers). Since 1993, the production and provision of CMDs have been subject to European Union (EU) Directive 93/42/EEC (Medical Device Directive, MDD) given effect in the UK by The Medical Devices Regulations 2002 (Statutory Instrument 2002/618), and its subsequent amendments. Regulation (EU) 2017/745 (Medical Device Regulation, EU MDR) replaces the MDD and the other EU Directive pertaining to Medical Devices, Council Directive 90/385/EEC (Active Implantable Medical Device Directive, AIMDD). The EU MDR was published on 5 April 2017, came into force on 25 May 2017 and, following a three-year transition period was due to be fully implemented and repeal the MDD on 26 May 2020, but was deferred until 26 May 2021 due to the coronavirus disease 2019 (COVID-19) pandemic.In the UK, in preparation for the country's planned departure from the EU, the EU MDR, with necessary amendments, was transposed into UK law (Medical Devices (Amendment etc.) (EU Exit) Regulations 2019, UK MDR). The UK left the Union on 31 January 2020 and entered a transition period that ended on 31 December 2020, meaning that, from 1 January 2021, dental professionals in Great Britain who prescribe and manufacture CMDs are mandated to do so in accordance with the new legislation while Northern Ireland remains in line with the EU legislation and implementation date. This paper sets out the requirements that relate to the production and provision of CMDs in a UK dental setting.

Influence of Fixed Orthodontic Therapy on Pharyngeal Airway Dimensions after Correction of Class-I, -II and -III Skeletal Profiles in Adolescents

The aim was to compare the influence of fixed orthodontic therapy (OT) on the pharyngeal airway space dimensions after correction of class-I, -II and -III skeletal profiles and among untreated adolescent patients. A control group comprising of untreated patients was also included. Demographics and OT-related information was retrieved from patients’ records. Measurements of airway spaces in the nasopharynx, oropharynx and hypopharynx were performed on lateral cephalograms. p-values under 0.05 were considered statistically significant. The results showed no statistically significant differences in the naso-, oro- and hypo-pharyngeal airway spaces among patients with class-I, -II and -III skeletal profiles and individuals in the control group. There were no statistically significant differences when naso-, oro- and hypo-pharyngeal airway spaces were compared among patients with class-I, -II and -III skeletal profiles. In conclusion, in non-extraction cases without maxillary expansion, fixed OT does not affect the naso-, oro- and hypo-pharyngeal airway spaces in patients with skeletal Class-I, -II and -III skeletal profiles. Further studies involving patients undergoing ME and premolar extraction are needed to elucidate the influence of fixed OT on the naso-, oro- and hypo-pharyngeal airway spaces.

Short-term efficacy of vacuum-formed maintainer for deciduous second molar space maintenance in the mixed dentition: A single-centre, randomized controlled clinical trial

OBJECTIVE

To compare the efficacy of vacuum-formed and banded space maintainers for deciduous second molar space maintenance during the mixed dentition.

SETTING AND SAMPLE POPULATION

The study sample comprised thirty children in the mixed dentition (age range, 5.9 to 9.8 years) with early loss of at least one deciduous second molar.

METHODS

This was a parallel-group, randomized, active-controlled clinical trial. Patients were randomly allocated to space maintenance performed with vacuum-formed or banded space maintainers with a 1:1 allocation ratio. The main outcome was any change in mesiodistal width of the extraction space. Secondary outcomes included the lingual rolling or axial rotation of the permanent first molar adjacent to the extraction site and extrusion of the antagonist tooth. Dental casts were obtained before appliance installation (T0), after 3 months (T1) and after 6 months (T2). Digital dental casts were measured using Dolphin 3D software. Chi-square, t test or Mann-Whitney and ANOVA or Friedman test were used for intra- and intergroup comparisons (P < .05).

RESULTS

Baseline characteristics were similar between groups except for chronological age. Statistically, but not clinically significant space loss (mean, 0.32 mm; SD, ± 0.39) occurred with the vacuum-formed space maintainer only at the first trimester (T0-T1). Lingual rolling and axial rotation of the first permanent molar were not significant, as well as extrusion of the antagonist tooth.

CONCLUSIONS

The results of this study suggested that both tested devices were effective in maintaining space after early extraction of the deciduous second molar over a period of 6 months.

Initial Bacterial Adhesion and Biofilm Formation on Aligner Materials

The present study aims to assess the initial bacterial adhesion and biofilm formation on different aligner materials. A total of four different aligner materials, CA-medium (CAM), copolyester (COP), Duran (DUR), Erkodur (ERK), were tested. Stimulated human saliva was obtained from six healthy volunteers. Salivary bacteria were harvested by centrifugation, and 1 mL of the salivary suspension was injected onto each sample surface for 2 h and 3 days, respectively. The samples were then washed twice with 5 mL 0.9% NaCl solution, and non-adherent bacteria were removed. The adherent microorganisms were dislodged from the sample surfaces after ultrasonication for 4 min in 1 mL 0.9% NaCl on ice. After the incubation of the adherent salivary bacteria under both aerobic and anaerobic conditions on Columbia blood agar plates at 37 °C and 5% CO₂ and in anaerobic jars overnight, several dilutions thereof were used for the determination of CFUs. This protocol was applied three times, obtaining an average of nine independent measurements for each material group. Overall, the differences between the tested aligner materials as well as between the materials and controls were not of statistical significance (p > 0.05). Regarding initial bacterial attachment and biofilm formation, the tested aligner materials are comparable to enamel and metal orthodontic brackets and can be therefore considered for clinical use. The four tested aligner materials CAM, COP, DUR, ERK showed no significant differences in initial microbial attachment and biofilm formation of aerobic and anaerobic species compared to enamel and conventional brackets.

Bending Behaviour of Polymeric Materials Used on Biomechanics Orthodontic Appliances

This paper discusses the issues of strength and creep of polymeric materials used in orthodontic appliances. Orthodontic biomechanics is focused on the movement of individual teeth or dental groups as a result of the force applied by orthodontic appliances. Stresses in the construction of functional and biomechanical appliances is generated when using the apparatus in the oral cavity. The orthodontic appliance must maintain its shape and not be damaged during treatment so strength and creep resistance are fundamental properties. It was assumed that the clinical success of orthodontic appliances can be determined by these performance properties. The aim of the work was the experimental assessment of comparative bending strength and creep resistance of selected popular polymer materials used in the production of biomechanical orthodontic appliances. Four commercial materials manufactured by the world class producers were tested: NextDent Ortho Rigid (Vertex-Dental B.V., Soesterberg, The Netherlands) marked as "1A"; Erkocryl (ERKODENT Erich Kopp GmbH, Pfalzgrafenweiler, Germany)-"2A"; Vertex Orthoplast (Vertex Dental B.V.), blue, marked as "3A" and material with the same name as "3A" but orange, marked in the article as "4A". All the tests were carried out after aging in artificial saliva for 48 h at a temperature of 37 °C. Flexular strength and flexular modulus were made using the three point bending method according to the ISO 178 technical standard. Creep tests were carried out according to the method contained in ISO 899-2. The creep test was carried out in an artificial saliva bath at 37 °C. The creep tests showed significant differences in the strength, modulus and deformability of the tested materials. The strength reliability of the tested materials also varied. The research shows that the 2A material can be used for orthodontic applications in which long-term stresses should be lower than 20 MPa.

Spontaneous repair of iatrogenic root perforation by an orthodontic miniscrew: A case report

BACKGROUND AND OVERVIEW

Orthodontic miniscrews have become popular tools for providing temporary anchorage during orthodontic treatment. Although they are easy to insert, damage to the periodontal ligament or dental root during insertion is an unfavorable iatrogenic complication. Root perforation during miniscrew insertion in human teeth has been reported in a few articles. In this article, the authors describe the spontaneous repair of an iatrogenic root perforation in a mandibular first molar that occurred during insertion of an orthodontic miniscrew in a young girl undergoing orthodontic treatment.

CASE DESCRIPTION

A 15-year-old girl with malocclusion was undergoing orthodontic treatment when the mesial root of her mandibular right first molar was damaged by an orthodontic miniscrew. The miniscrew and corresponding bracket were immediately removed to avoid any unnecessary forces on the tooth. Because the pulp remained vital without any additional damage and infection for 6 months, orthodontic treatment was resumed and completed in 9 months without any pulp damage or unfavorable symptoms. Serial periapical radiographs and cone-beam computed tomographic images showed that the injured area was surrounded by reparative tissue without any apical lesion.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The findings of this case suggest that immediate removal of unnecessary forces provides an environment for spontaneous repair in cases of iatrogenic root perforation by orthodontic miniscrews, even when the damage involves the pulp. If force stimulation is avoided for a certain period, which was 6 months in this case, it may be possible to complete the orthodontic treatment without unfavorable symptoms.

Are Metal Ions That Make up Orthodontic Alloys Cytotoxic, and Do They Induce Oxidative Stress in a Yeast Cell Model?

Compositions of stainless steel, nickel-titanium, cobalt-chromium and β-titanium orthodontic alloys were simulated with mixtures of Fe, Ni, Cr, Co, Ti and Mo metal ions as potential oxidative stress-triggering agents. Wild-type yeast Saccharomyces cerevisiae and two mutants ΔSod1 and ΔCtt1 were used as model organisms to assess the cytotoxicity and oxidative stress occurrence. Metal mixtures at concentrations of 1, 10, 100 and 1000 µM were prepared out of metal chlorides and used to treat yeast cells for 24 h. Every simulated orthodontic alloy at 1000 µM was cytotoxic, and, in the case of cobalt-chromium alloy, even 100 µM was cytotoxic. Reactive oxygen species and oxidative damage were detected for stainless steel and both cobalt-chromium alloys at 1000 µM in wild-type yeast and 100 µM in the ΔSod1 and ΔCtt1 mutants. Simulated nickel-titanium and β-titanium alloy did not induce oxidative stress in any of the tested strains.

Comparison of biochemical markers of bone metabolism between conventional labial and lingual fixed orthodontic appliances

Objectives

The applied orthodontic force causes remodeling of the periodontium through the selective release of cytokines causing resorption of bone, enabling controlled movement of the tooth. This study compared the cytokine profile between patients treated with conventional labial and lingual fixed orthodontic appliances.

Patients and Methods

The study included 80 patients in need of orthodontic treatment, out of which 40 patients were treated by the labial fixed appliance and 40 by the lingual fixed appliance. Gingival crevicular fluid (GCF) specimens were gathered from both the groups using a microcapillary pipette. The samples were collected at the beginning of the treatment and after 21 days. Enzyme-linked immunosorbent assay was performed to evaluate the cytokine levels.

Results

Interleukin (IL)-1α, 1β, 2, 8, and tumor necrosis factor-alpha (TNF-α) levels were significantly high (P < 0.001) in GCF of participants treated with conventional labial fixed appliance. IL-1α, 1β, 2, 6, 8, and TNF-α levels were significantly high (P < 0.001) in GCF of participants treated by the lingual fixed appliance. The concentrations of TNF-α and IL-1β were increased higher than other cytokines in both the treatment groups.

Conclusion

Overall, the lingual fixed appliance had higher cytokine levels than a labial fixed appliance. Analyzing the GCF cytokine levels during orthodontic treatment could provide an ideal platform for monitoring the progress of the treatment.

Direct-to-consumer orthodontics: surveying the user experience

BACKGROUND

The rise of direct-to-consumer (DTC) orthodontics has caused significant controversy among dentists and orthodontists. However, little is known about the actual harms or benefits experienced by users of at-home teeth aligners.

METHODS

The authors designed a 24-item online survey to assess users' experiences with at-home aligners. The authors recruited users for 6 months (March-August 2019) on social media platforms (Instagram, Twitter) and online forums related to DTC orthodontics. A total of 470 responses were analyzed.

RESULTS

The typical respondent was a white, female millennial (23-38 years old in 2019) who purchased aligners to correct crowding. More than one-half of respondents consulted with a dentist before purchasing aligners. In those interactions, the dentist most often recommended an in-office treatment. Although most respondents (87.5%) were satisfied with DTC treatment, 6.6% had to visit their dentist due to the severity of adverse effects.

CONCLUSIONS

Although many respondents would have preferred traditional treatment from a dentist or orthodontist, they opted for DTC aligners because of cost and convenience.

PRACTICAL IMPLICATIONS

Rather than warning patients wholesale against at-home aligners, it might be more productive for dentists to have frank discussions with them about the risks and benefits. In parallel to pushing for increased accountability, it might be prudent to consider new ways of coexisting in this altered landscape, such as offering professional oversight of DTC treatments.

Effect of class II extractions and functional appliance treatment on smile esthetics

BACKGROUND

Class II malocclusion is routinely observed in orthodontics. Its treatment usually revolves around the growth modification or the extractions of the teeth. Identifying treatment that leads to the greatest improvement can aid clinicians in providing the desired smile esthetics.

OBJECTIVES

The aim of the study was to compare smile esthetics between treatment groups by measuring various smile variables and the esthetic perceptions of 3 panels of raters.

MATERIAL AND METHODS

A cross-sectional study was performed on 66 patients equally divided into the functional appliance (FA) and upper first premolar extraction (UPE) groups. Eight smile variables were measured on post-treatment photographs using the Adobe Photoshop® software. Ten orthodontic residents, general dentists and laypersons performed the subjective evaluations of smiles using the visual analog scale (VAS). The Mann-Whitney U-test was applied to compare smile variables between the groups. The Kruskal-Wallis test was used to compare esthetic scores (ES) among the raters. The simple linear regression analysis, followed by the multiple linear regression analysis was applied to determine the smile variables associated with the ES values.

RESULTS

Statistically significant differences were found between the FA and UPE groups for the buccal corridor ratio (BCR) (p = 0.046), the visible dentition width ratio (VDWR) (p = 0.019) and the arch form index (AFI) (p < 0.001). The Kruskal-Wallis test showed significant differences in ES among the raters for the FA (p < 0.001) and UPE (p = 0.004) groups. The simple linear regression analysis showed significant associations between ES and the patient's age (p = 0.002), BCR (p = 0.020) and VDWR (p = 0.006). The multiple linear regression analysis showed that age (p = 0.008) and VDWR (p = 0.021) were significantly associated with the ES values.

CONCLUSIONS

The FA group had narrower buccal corridor spaces, a greater visible dentition width and a wider arch form in their smiles. The UPE group showed an increase in the buccal corridor width. Each panel rated the FA appliance group as superior.

Torque expression by active and passive self-ligating brackets in patients with four premolar extractions: A retrospective study

OBJECTIVE

Appropriate torque expression contributes to ideal treatment outcomes both clinically and aesthetically. Whether active and passive self-ligating brackets (SLBs) have different torque-control capability in vivo has never been reported. The purpose of present study was to explore whether there was difference in torque expression in active and passive SLBs.

SETTING AND SAMPLE POPULATION

In this retrospective study, 225 patients with four first premolar extractions were enrolled. For each patient, the digital lateral cephalometric radiographs were taken before and after treatment.

MATERIALS AND METHODS

The study consisted of 2 groups: 111 subjects were treated with passive SLBs (Damon Q, Ormco) and 114 subjects with active SLBs (Empower 2, American Orthodontics). Measurements to determine skeletal changes and incisor inclination were obtained from cephalometric tracings using Dolphin software (version 11.8, USA). Comparisons in both groups and intergroups were compared using t tests and chi-square test.

RESULTS

Significant differences in the variation of U1-SN(°), U1-NA(°), L1-NB(°) and L1-FH(°) were found between two groups. More labially inclined maxillary incisors were found in active SLB group, while more labially inclined mandibular incisors were observed in passive SLB group.

CONCLUSIONS

With the present prescription set in the two brackets, active SLBs achieved more proclined maxillary incisors and retroclined mandibular incisors. Clinicians should take torque expression of brackets into consideration during orthodontic treatment.