Metal Braces Research Articles

Changes in heavy metal levels in the oral fluid of young patients with and without plaque-induced gingivitis undergoing treatment with braces

Relevance. Research into the effects of nickel-titanium alloys and heavy metal ions on the development of inflammatory oral diseases is becoming increasingly significant in orthodontics. The relationship between toxic elements and inflammatory responses remains under-researched and controversial. Data on the connection between heavy metals and inflammatory reactions could influence the choice of orthodontic appliance materials and guide the subsequent management and monitoring of patients with braces. The question of the safe use of nickel-titanium alloy braces continues to be a relevant concern.Purpose. To assess the levels of heavy metals in the oral fluid of young patients with braces, both in those who developed plaque-induced gingivitis and those who did not.Materials and Methods. The study involved 50 clinically healthy patients (Groups I and II health categories) with intact teeth, including patients with compensated dental caries (isolated carious lesions – Grade I) and no periodontal diseases (PMA index <20), presenting with dental crowding and malocclusion (K07.2, K07.3). The average age of the patients was 22.1 ± 2.7 years, all of whom were undergoing treatment with metal braces. Oral fluid samples were analyzed for 12 heavy metal elements using inductively coupled plasma mass spectrometry (ICP-MS) in a laboratory setting. Additionally, lysozyme activity and oral fluid pH were measured before appliance placement and six months into orthodontic treatment.Results. Adaptation to braces in young patients is frequently complicated by the development of gingivitis and periodontitis due to impaired oral hygiene and the mechanical pressure exerted on teeth and gums, leading to elemental imbalances. Patients with gingivitis during orthodontic treatment are particularly at risk of developing such imbalances and therefore require timely correction of their mineral metabolism.

Microbial adhesion on different types of orthodontic brackets and wires: An in vitro study

ObjectiveThe objective of this study was to compare the microbial adhesion of different oral pathogens on different wires used in orthodontic treatment and to evaluate the potential of these pathogens to form biofilms on different types of orthodontic wires and brackets. MethodsIn this in vitro investigation, we calculated that the sample size for each group (i.e., those with brackets [metal braces, ceramic braces, and self-ligating braces] and wires [nickel titanium, titanium molybdenum, and stainless steel]) should be 15 individuals. Five types of microbes (Streptococcus mutans, Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, and Candida albicans) were used. Three types of brackets and three types of wires were used with five types of bacteria, and the process was repeated three times to collect the average. ResultsNo significant differences were observed in the mean concentrations of bacteria in the different brackets (p > 0.05) or in the mean concentrations in the different orthodontic materials used in these brackets. In contrast, there were considerable differences between the concentrations of bacteria in the wires and those in the brackets (p < 0.05). ConclusionDifferent wires and brackets have different associations with bacterial adhesion and concentration. The wires exhibited more substantial biofilm absorbance and concentrations than the brackets. The adhesion of biofilm may be a decisive factor when choosing a type of orthodontic wire, particularly for individuals at high risk of developing bacterial oral diseases, such as periodontal diseases and dental caries.

Management of white spot enamel lesions with resin infiltration: potentials and future research directions.

The current study1 is a randomized controlled trial with two arm, multicenter and parallel group design. Study subjects were 38 orthodontic patients younger than 17 years who were being treated with metal braces. Patients with at least one white spot lesion (WSL) graded 1 to 2 according to the International Caries Detection and Assessment System (ICDAS) on the labial surface of permanent maxillary and mandibular canines and incisors were included for the trial. Teeth with carious lesions and restorations, anomalies of the enamel, and primary teeth were excluded. Patients were allocated by computer generated random sequence into resin infiltration and fluoride varnish intervention groups. Study subjects were blinded until the allocation, outcome assessors and statisticians remained blinded through the study, however the operators could not be blinded. Resin infiltration treatment involved removal of orthodontic wires and auxiliaries followed by cleaning the teeth with fluoride free prophylactic paste and completing the resin infiltration according to manufacturer's instructions. In the fluoride varnish group, a thin layer of the material was applied after isolating the teeth, and patients were asked not to eat or drink for 1 hour. This was continued twice a month for 6 months. Digital images of the teeth were obtained before, and 1 day (T1), 1 week (T2), 1 month (T3), 3 months (T4) and 6 months (T5) after treatment, using a DSLR camera and a matching polarization filter. The images were processed for calibration and color stability. Regions of interest representing WSL (white spot lesion) and SAE (sound adjacent enamel) were isolated in the images for comparison at different stages the images were captured. Statistical analysis was performed using SPSS version 28. Independent-samples t-test was utilized for comparison between the two groups, and paired-samples t-test for comparison within the groups. A statistical significance level of α = 0.05 was set. At T1, significant color difference was observed between white spot lesion and adjacent sound enamel in the resin infiltration group and it remained stable after 6 months. Whereas in the fluoride varnish group, there were no statistical differences from baseline to 6 months. A statistical difference of 3.27 CIELAB units (p < 0.001) was reported between the infiltration group and the fluoride group at T5. No significant changes were noted in SAE with respect to changes in lightness. Resin infiltration was found to be better at masking the demineralization produced by WSL and also enhanced the esthetic appearance of demineralized areas around the brackets. Resin infiltration did not produce any clinically visible effects in non-affected enamel. These changes remained stable for a period of 6 months.

Accessories in clear aligner therapy: Laypeople's expectations for comfort and satisfaction.

This study explored the layperson's perception of comfort, satisfaction, and willingness to use various accessories in clear aligner therapy. A total of 267 people analyzed standardized intraoral photographs of a female model in orthodontic treatment using: 1) only clear aligner (CA), the control group; 2) clear aligner+attachments (AT); 3) clear aligners+Cl II elastics (EL); 4) clear aligner+hybrid treatment with esthetic braces (HEB); 5) Clear aligner+hybrid treatment with metallic braces (HMB); 6) clear aligner+mini-implants (MI); 7) clear aligner+mini-implants and elastics for intrusion (MIE). In addition, a social media questionnaire was distributed to assess the willingness to undergo orthodontic treatment with various accessories. There was a significant difference between CA and all the other groups (P<0.001), with CA being considered more comfortable and providing greater satisfaction compared to other accessories. Moreover, AT showed a significant difference in reducing treatment time compared to other groups. The CA was the most comfortable, exhibiting a higher satisfaction rate and a greater willingness to use it. The AT therapy was perceived as more comfortable and was associated with higher satisfaction and a greater likelihood of use, especially if it resulted in reduced treatment time. On the other hand, the participants reported that the HMB, MI, and MIE accessories were less comfortable.

Analysis of the Effects of Different Orthodontic Appliances on Salivary pH Levels: An In vitro Approach.

Orthodontic appliances can influence the oral environment, including salivary pH levels, which play a crucial role in maintaining oral health. Understanding how different orthodontic appliances affect salivary pH levels can help in improving treatment outcomes and minimizing potential side effects. In this in vitro study, we evaluated the effects of various orthodontic appliances on salivary pH levels using a simulated oral environment. Four different types of orthodontic appliances were tested: traditional metal braces, ceramic braces, lingual braces, and clear aligners. Saliva samples were collected and subjected to pH measurements using a standardized method. The pH measurements were recorded at three different time intervals: immediately after appliance placement, after 24 hours, and after 48 hours. The initial pH values varied among the different orthodontic appliances: metal braces (pH 7.2), ceramic braces (pH 7.4), lingual braces (pH 7.1), and clear aligners (pH 7.5). After 24 hours, there was a decrease in pH levels for all groups: metal braces (pH 6.8), ceramic braces (pH 7.0), lingual braces (pH 6.7), and clear aligners (pH 7.2). After 48 hours, the pH levels continued to decrease: metal braces (pH 6.5), ceramic braces (pH 6.8), lingual braces (pH 6.4), and clear aligners (pH 6.9). Our findings suggest that different orthodontic appliances have varying effects on salivary pH levels. Metal braces and lingual braces tend to cause a more pronounced decrease in salivary pH compared to ceramic braces and clear aligners. Monitoring salivary pH levels during orthodontic treatment may be beneficial in identifying potential risks to oral health and implementing appropriate interventions.

Orthodontic patient satisfaction: Validation of an Arabic patient satisfaction questionnaire

Objectives: Orthodontic patient satisfaction is a primary aim of orthodontic treatment. Satisfaction is a multidimensional concept, requiring multi-item questionnaires for it to be adequately assessed. A 58-item, orthodontic patient satisfaction questionnaire (PSQ) was developed to assess orthodontic patient satisfaction. Appropriately adapted assessment tools are needed to assess orthodontics patient satisfaction in different populations. The validity and reliability of such tools should be demonstrated before their use for each target population. The PSQ was yet to be validated in Arabic. Therefore, the objective of this study was to translate, adapt, and validate an Arabic orthodontic PSQ. Material and Methods: The 58-item English PSQ was translated to Arabic through translation and back-translation. An expert panel examined the relevance of PSQ items. The questionnaire was circulated through social media to recruit responses from Arabic-speaking orthodontic patients who completed orthodontic treatment. Cronbach’s alpha, item-total correlation (I-TC), and kappa reliability coefficient were calculated. The analysis of variance test was used to compare satisfaction scores between genders and different orthodontic treatment appliances. Results: Ten items were removed based on expert ratings. The questionnaire was filled by 327 patients (55.6% females, mean age = 28.5 ± 7.2, 59.8% on metal braces, 35.3% on clear aligners, and 5.2% on tooth-colored braces). Nine questionnaire items were removed because of low I-TC (&lt;0.3). The resulting 39-item questionnaire had a Cronbach alpha of 0.79 and a kappa coefficient of 0.82. The mean total PSQ score of the sample was 167.61 ± 21.45. Items with the top ten highest I-TC correlations had a Cronbach’s alpha of 0.90. Patients on metal braces had a highest mean total PSQ score (P = 0.004). Among these patients, satisfaction with situational aspects was lower but satisfaction with dentofacial, psychosocial, and dental improvements were all higher compared to other orthodontic treatments (P &lt; 0.001). Conclusion: The 39-item Arabic PSQ is valid and reliable. A shorter collection of 10 items with high validity were identified. Patients on metal braces had better outcomes, driving higher satisfaction. Studies collecting satisfaction data using the PSQ from orthodontic clinics are needed.

Oral Infection by Lichen Planus: Types, Relevance, and Significance: A Review

Lichen planus is a chronic inflammatory condition that affects the skin. It is referred to as oral lichen planus (OLP) when it develops inside the mouth. The condition may only occur in the mouth or also affect other body parts at the same time. It can also occur in the genitals, nails, and scalp. The condition is marked by the onset of a non-infectious, itchy rash. The rash is often small with an irregular shape. It also has a flat top and appears as pink or purple bumps. OLP affects about 1% of the population. OLP is sometimes triggered by the body's reaction to metals placed in the mouth. Examples are dental fillings and metal braces. There have also been reports of the disorder occurring due to mouth mannerisms. Examples are biting the cheeks or tongue. Clinically, six types of OLP, namely reticular, popular, plaque-like, atrophic/erosive, ulcerative, and bullous types, can be identified. OLP more commonly affects the buccal mucosa, tongue, and gingiva. It is important to note that OLP is not an infection. It is also not contagious. It is not passed on from person to person. It is also not linked to nutrition or nutritional deficiency. However, eating certain fruits, tomato-based products, and spicy food has been found to make the symptoms worse. OLP is more common in women than men. It is often diagnosed in patients aged 40 and above. However, it can also affect children and young adults.

A Review on Orthodontic Brackets and Their Application in Clinical Orthodontics.

Braces are undoubtedly a blessing for those whose teeth are misaligned in various ways, yet many people may not enjoy the traditional metal braces. However, some people are totally fine with having their teeth fused with the set of metal brackets and various metal components flowing through. A few people may simply not feel comfortable in that way. Orthodontists have developed a huge array of bracket styles by concentrating on the wide range of preferences and financial constraints that their patients present. These various dental bracket types are all advantageous from one point of view or another. Orthodontic supplies and materials are being produced using technology that is advancing exponentially. Every day, more technologies, processes, and designs emerge. These tools assist the orthodontist in providing patients with the best functional and cosmetic outcomes. Since Edward Hartley Angle's time through MBT brackets and then lingual brackets, orthodontic brackets have advanced significantly. Orthodontists' lives have been greatly facilitated by these brackets. Numerous new materials and designs will be developed as technology progresses. The purpose of this article was to give a general overview of the different orthodontic brackets and demonstrate how the logic underlying them helps orthodontists in their day-to-day jobs.

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.

Orphan medical devices have come a long way

BackgroundIn many countries worldwide orphan drug regulations are installed but only the United States of America and Japan have an orphan device regulation. For many years surgeons have used off-label or self-assembled medical devices for the prevention, diagnosis or treatment of rare disorders. Four examples are given: an external cardiac pacemaker, a metal brace for clubfoot in newborns, a transcutaneous nerve stimulator and a cystic fibrosis mist tent.ConclusionIn this article we argue that we need authorized medical devices as well as medicinal products to prevent, diagnose and treat patients with life-threatening or chronically debilitating disorders with a low prevalence/incidence. Several arguments are given to support this statement.

The review of studies on the bonding of metal brackets to tooth enamel and ceramics

In our paper, we present a review of modern laboratory studies conducted on the topic bonding strength of brackets using adhesive systems. The main objective of this article is to study the structure of studies, the methods used and the results that were obtained. We selected scientific papers that compared the adhesion of metal braces with tooth enamel and ceramics, using various primers and adhesives. All studies that we selected were published no earlier than 2018. This article analyzes the methods of laboratory experiments, the samples used and the results obtained on the basis of these tests. The result of our review is the conclusion that it is possible to use an additional method to determine the adhesion force of a bracket with tooth enamel and orthopedic materials.&#x0D; Conclusions are drawn that in the analyzed works all the indicators of adhesion of braces with enamel are in the same range, the adhesion of braces with ceramics is lower compared to adhesion with tooth enamel, there is no data on laboratory studies of the adhesion strength on the separation of braces from tooth enamel and ceramic orthopedic structures.

Shear Bond Strength, Bonding Time and Adhesive Remnant Index of Adhesive Precoated Flash Free Adhesive System vs Conventional Adhesive System using Metal Brackets: An In-vitro Study

Introduction: With advances in materials for bonding in orthodontics, errors regarding amount of adhesive to be used can be controlled. Adhesive Precoated (APC™) Brackets were introduced to reduce the step of applying conventional adhesive on base of the bracket. Moreover, APC™ Flash Free Adhesive System (FFAS) eliminated the step of removal of excessive adhesive around the brackets. Aim: To compare Shear Bond Strength (SBS), Bonding Time (BT) and Adhesive Remnant Index (ARI) between Conventional Adhesive System (CAS) and APC™ FFAS using metal brackets Materials and Methods: This in-vitro study was carried out in the Department of Orthodontics and Dentofacial Orthopaedics at Bharati Vidyapeeth (Deemed to be University) Dental College and Hospital, Sangli, Maharashtra, India. A total of 78 teeth with metal braces were split into two groups, with 39 samples each receiving treatment with the CAS and the APCTM FFAS. Shear bond forces were applied to each sample using a universal testing machine and recorded in Megapascals (MPa) to provide an indication of SBS. Both Groups’ BT was quantified in terms of seconds. The stereomicroscope indexes of Artun J and Bergland S were used to determine ARI. Microsoft Excel was used for data entry, while Statistical Package for Social Sciences (SPSS) version 24.0 was used for analysis. The normality of the data was tested using two different t-tests. In terms of mean and standard deviation, descriptive statistics were represented. A significant level of 0.05 was used. Results: SBS values were 10.35±3.55 MPa and 11.23±3.82 MPa in CAS and FFAS respectively. No significant difference was found among the two groups (p≤0.29) in SBS. BT was significantly (p≤0.001) less in FFAS (95.54±8.72 seconds) compared to CAS (140.85±16.62 seconds). ARI was significantly (p≤0.002) less in FFAS (1.79±0.80) in comparison with CAS (1.23±0.74). Conclusion: FFAS brackets perform better in comparison to CAS in case of BT and ARI. Both groups show no significant difference in SBS.

Seismic Analysis for Zone III, IV, V of (G+14) Multistorey Building with Bracings System Using Staad Pro Software

Abstract: This present study focuses G +14 Simple Building model In STAAD PRO software. With beam size 300 X 400 mm and column size 400 X 500 mm this reinforced concrete building having M30 grade of Concrete and Fe415 high density steel. To study the response of building with and without bracing system. The performance of the building is analyzed in Zone III, Zone IV, Zone V. Metallic braces is the easiest of simplest way of reducing response of building which gave rise to nine models for the analysis.Model1 in -BFB- Bare frame RCC Building.Model2 in -BX1-Framed building with Bracing at the exterior side along X-direction.Model3 in -BY2- Framed building with Bracing at the exterior side along Y-direction.Model4 in -BXY3- Framed building with Bracing at the exterior side along X and Y-direction.Model5 in-BEC4- Framed building with Bracing at the exterior side around the corners. This system of bracing is used because eccentric bracing systems consist of a link element that undergoes inelastic deformation for energy dissipation. This link is possibly beam element of frame structure which is more suitable for steel structures and not for reinforced concrete structures and a shear wall is a structural panel that can withstand the impact of lateral forces on it. Lateral forces are those parallel to the wall plane and are usually wind loads and seismic loads. This building has been modeled as 3D Space frame model with six degree of freedom at each node using STAAD PRO. software for stimulation of behavior under gravity and seismic loading.

Clinical, histopathological and immunohistochemical changes of the superficial marginal periodontium caused by orthodontic treatment with fixed metallic orthodontic appliances.

Malocclusions negatively influence dental function, physical well-being, and quality of life. According to data provided by the World Health Organization (WHO), malocclusions represent the third most widespread oral health problem, after dental caries and periodontal diseases. In recent years, more and more people call for orthodontic treatment with fixed braces that aim at establishing a dental, aesthetic, and functional balance, compatible with a normal life. Our study assessed the histopathological and immunohistochemical changes that occurred in superficial marginal periodontal components, in a number of 23 patients diagnosed with malocclusions, as a result of orthodontic treatment with fixed metal braces. The purpose of the study was to evaluate the remodeling of the tissues in the superficial periodontium during orthodontic migration, microscopic aspects that are essential to evaluate the effectiveness of the orthodontic treatment.

Factors influencing the decision to initiate orthodontic treatment and the choice of appliance type in a Lebanese sample during the COVID-19 pandemic and the economic crisis. A cross-sectional study

Background: The spread of Coronavirus Disease 2019 (COVID-19) has led to a major public health issue. This study aimed to assess the factors that influence the Lebanese people in undergoing an orthodontic treatment after the outbreak of COVID-19, as well as the factors that influence their choice of orthodontic appliance type. Methods: 489 Lebanese participants (199 men and 290 women) were invited to fill a questionnaire developed on Google Forms. Eligible participants were simply Lebanese people including those who immigrated during the crisis. Dentists, dental students and foreigners were excluded from the study. The link for the questionnaire was sent to the patients via WhatsApp. It is a brief, structured 10-item questionnaire that assesses the relationship between the economic recession and the COVID-19 pandemic and the Lebanese participants' decision to initiate orthodontic treatment and their choice of appliance type. Results: A total of 489 responses were obtained: 199 men (41%), 290 women (59%) with a mean age of 24 years ±8.4 years (age range: 13 to 64 years). Half of the participants feel anxious in consulting for an orthodontic opinion during the pandemic. Almost half of the respondents are thinking of starting orthodontic treatment after the start of COVID-19. The responses showed that most participants (71%) believe that the current economic crisis in Lebanon influences their decision to start an orthodontic treatment. Regarding the choice of the type of orthodontic appliance, a higher number of respondents choose metal braces (traditional) than other appliances. In a normal situation, the aesthetic of the appliance is the most important factor in choosing the appliance. Conclusion: The COVID-19 pandemic and the current economic crises in Lebanon had a negative impact on the financial and emotional well-being of the Lebanese people, on their decision to initiate an orthodontic treatment as well as on choosing the type of the appliance. However, despite the difficult circumstances facing the country, a big part of the respondents was not discouraged from initiating treatment.

Microbial Corrosion in Orthodontics

Even with the exponential popularity of the contemporary clear aligners, the main stream of orthodontic practice still remains to be metal braces especially in adolescent age-group.1 Along with the advantages of metal braces such as lower cost, reduced friction, etc., there goes the disadvantages such as corrosion possibility, reduced esthetics, etc. Corrosion of orthodontic appliances is a widely researched topic.2-5 It is surprising to learn that microbially induced corrosion (MIC) has not been addressed in orthodontic literature till date. Microbial corrosion is an interesting arena which requires knowledge of both corrosion science and microbiology. The microorganisms capable of corrosion include various bacteria, fungi, and algae. The most common among them which has been widely indicated in MIC are the bacteria belonging to the sulfur cycle especially the sulfate-reducing bacteria (SRB). The connecting knot with orthodontics is the reported prevalence of these SRB in the oral cavity. SRB is prevalent in healthy individuals,6,7 patients associated with periodontitis6-11 and patients with gastrointestinal issues.12-14 The prevalence of SRB in the oral cavity has a greater clinical implication since the SRB have been proven to cause corrosion of stainless steel.15-24 There is literature attributing SRB as a potential cause in periodontal diseases7-11 as well as gastrointestinal diseases such as ulcerative colitis, inflammatory bowel diseases, and Crohn's disease.12 With its presence in the healthy oral environment already reported in the previous studies,6,7,25,26 it further emphasizes the absolute need to be researching on its corrosion possibility in the intra oral environment. The genus generally found intraorally was Desulfovibrio and Desulfobacter10 which is commonly regarded as the most "opportunistic" and ubiquitous group of sulfate reducers.6,7 There is an interesting literature on the inhibition of Desulfovibrio spp. by human saliva, the reason being quoted as salivary nitrate and nitrite.14 The mechanism behind the antimicrobial action of nitrate and nitrite is that they increase the oxidative stress on the bacteria.27 However, concentrations of salivary nitrate vary depending on the food intake, endogenous production, and salivary flow rate.28,29 Despite there exist natural inhibitors, the prevalence in oral cavity is high, 22% in healthy and 86% in patients associated with periodontitis.7 There is a predilection for the bacteria to grow when favorable conditions exist. Biofilms is one such favorable medium for the growth of SRB. Paster et al.26 identified SRB in biofilms of patients associated with refractory periodontitis, periodontitis, acute necrotizing ulcerative gingivitis (ANUG), and also in healthy subjects. Biofilm is a surface film composed of organic and inorganic saliva components that are colonized with microorganisms in extracellular polymeric substances adsorbed on all surfaces in the oral cavity.30 The oral biofilm formation is a complex process involving interspecies aggregation, which is surrounded by a cohesive matrix, forms a complex structure which in turn facilitates anaerobic growth. It is the intrinsic nature of oral biofilms which make the survival of facultative anaerobes such as SRB in the oral cavity possible. Literatures31-35 report that there are increased biofilm formations in orthodontic patients due to increased retentive areas caused by the brackets, ligatures, wires, mini implants, force components, and archwires. Bacteria in dental plaque function as a metabolically, functionally, and physically integrated community.36 The study by Mystkowska et al.37 mentioned that biofilm per se play a critical role in corrosion process by forming corrosive microcells. With time-dependent association, the microbes in the biofilm, along with saliva acting as an electrolyte and components from food, causes a decreased pH in the areas immediately under the biofilms. The decreased pH along with a change of oxygenation releases metal oxides and hydroxides from the metal surface ultimately leading to the corrosion of metallic structures.37-41 The initial roughness also acts in a vicious form promoting more biofilm adherence and the process repeats causing more corrosion. With the biofilm itself serving to initiate and propagate corrosion, the increased prevalence of SRB in patients associated with orthodontics treatment all the more increases the possibility of MIC of orthodontic materials.

Quantification of Salivary Nitric Oxide in Patients with Fixed Orthodontic Treatment

Nitric oxide (NO) is considered a regulator of bone response to mechanical stress that mediates adaptive bone formation, the pathological effects of lipopolysaccharides (LPS), tumour necrosis factor (TNF), interleukin 1 (IL-1) and other cytokines; regulates leukocytes and epithelial cell adhesion; inhibits T cell proliferation; and enhances natural killer (NK) cell activity, as well as other immune-related processes. The aim of the current study was to test the potential use of salivary NO as a biomarker of bone response that is specific and sensitive to local changes, following the application of different types of dental appliances. Material and methods: Salivary NO was determined in 30 patients divided into three groups with 10 participants each: control (C), fixed metal braces group (M), and aligners group (A). Salivary NO was determined four times in each group (before the procedure, at 2 weeks, 30 days, and 60 days after the procedure) using ELISA and rapid semi-quantitative assay with Nitric Oxide Saliva Test Strips (Berkeley, CA, USA). The mean results were compared with the ANOVA test, and the Pearson correlation index was calculated. The results show a significant increase in salivary NO levels by both methods only in the metal braces group, which is suggestive of oxidative damage, increased invasiveness, and bone response to metal braces. In conclusion, our study showed that metal brackets lead to a significant temporary increase in oral oxidative stress as an adaptive reaction to the presence of foreign bodies in the oral cavity. The subsequent concentration decrease at 60 days suggests a normalization of the body’s response to foreign bodies.

Abstract P1003: Mechanical Loading Controls Cardiomyocyte Proliferation

Introduction: Mammal cardiomyocytes (CMs) lose their proliferative capacity early after birth and switch to an adult phenotype, characterized by organized sarcomeres. The mechanisms that control this switch remain largely elusive. Among the changes experienced by the heart at birth is a sudden increase in mechanical load. Hypothesis: This study tests the hypothesis that variations in mechanical loading may regulate both the proliferation and the maturation of cardiomyocytes. Methods: Engineered heart tissues (EHTs) were generated using neonatal rat heart cells, with a modified protocol allowing to alter mechanical load. Unloading is obtained by reducing the distance between the silicon posts that anchor the extremities of the EHT, while overloading is induced by changing Young’s module of posts using metal braces. Adult heart unloading in vivo was achieved by heterotopically transplanting a mouse heart into the neck of syngeneic recipient mice, which were injected with EdU twice per week. Both hearts, native and transplanted, were harvested at day 30. Results: In line with our hypothesis, mechanical unloading of developed EHTs significantly increased the percentage of EdU-, Ki67- and pH3-positive CMs at 72 hours. In contrast, increasing afterload induced CM maturation, characterized by increased cross-sectional area and force of contraction, associated with reduced proliferation. Consistently, heterotopically transplanted hearts showed a significant increase in the the number of proliferating CMs in both ventricles, which were almost absent in native hearts. Conclusions: Our data indicate that mechanical unloading induce CM proliferation in both rat EHTs and an in vivo in a mouse model of heterotopic heart transplantation. These results support our initial hypothesis and indicate that mechanical loading is a master regulator of cardiomyocytes proliferation and maturation. Ongoing experiments aim at identifying the molecular mechanisms that regulate this process.

Adult patient preference for an orthodontic care provider in Canada

This study evaluated the factors influencing potential orthodontic patients' choice between an orthodontist, general dentist (GD), and direct-to-consumer (DTC) aligners for their treatment and their choice of orthodontic appliance type and explored their motivating factors for seeking orthodontic treatment and preference for appliance type. An electronic survey was administered to 330 Canadian adults to determine demographic background, choice of the orthodontic treatment provider, the preferred mode of treatment, orthodontic issues they wished to address, and motivation for treatment. When participants were asked their preference in provider type, 49.4% of participants selected an orthodontist, 19.2% would follow the recommendation of their GD, 18.9% selected a GD, and 12.5% selected DTC aligners. Younger adult participants (P= 0.037) and those living in metropolitan areas (P= 0.0005) were significantly more likely to select an orthodontist than GD or DTC aligners. When asked about their preference in the mode of orthodontic treatment, 45.4% selected clear braces, 34.1% selected clear aligners, 14.3% selected metal braces, and 6.1% indicated they currently have no interest in orthodontic treatment. Older participants (P= 0.0005) and those in moderate-sized population centers (P= 0.001) were significantly more likely to select clear braces or aligners. Adults in Canada have a high preference for orthodontic treatment performed by orthodontists, especially among younger participants and those in metropolitan areas. Although all ages preferred clear braces, younger adult participants tended to be more open to metal braces, whereas older participants' preference for clear braces was the strongest. Preference for clear aligners is positively correlated to increased community size.

Motivation, Perception, and Behavior of the Adult Orthodontic Patient: A Survey Analysis.

Purpose The article is aimed at improving the understanding of the sociocultural profile of adult orthodontic patients and their expectations. In particular, it addresses three main aspects: the motivation and needs that underpin the decision to start orthodontic treatment, how it influences the patients' daily life, and the different oral hygiene demands. Materials and Methods An online survey was completed by 276 patients undergoing orthodontic treatment with different techniques. The questions asked concerned gender, age, type of appliance, any previous orthodontic treatments, type of any previous retainers, reasons for therapy, satisfaction, pain, problems in eating, daily number of teeth brushings and flossings before and during the treatment, perception of cost, sensation of visibility of the appliance, and if they would recommend orthodontic treatment. Results A significant role within our sample is played by gender; 87.94% consisted of female patients out of which 72.57% wanted to improve their aesthetics, while only 54.84% of male patients cited the same reason. Invisible aligners were preferred by 67.70% of the patients due to them being considered the least painful, causing the fewest problems with eating, and the least visible. Metal braces were perceived as the less expensive treatment. Over a third of the patients (33.85%) had previously undergone orthodontic treatment, among them 54.05% wore a mobile retainer, 31.08% a fixed one, and 14.86% both. Daily tooth brushing and flossing increased during therapy with clear aligners by 48.94% and 126.39%, respectively. Conclusions The greatest demand for orthodontic treatments comes from women, as they pay more attention to aesthetics, which makes the clear aligners the most common choice. The relapse after orthodontic treatment seems to cause a higher demand for retreatment, and oral hygiene habits significantly improve during orthodontic treatment, especially with the clear aligners.