Comparative characterization of supragingival plaque microbiomes in malocclusion adult female patients undergoing orthodontic treatment with removable aligners or fixed appliances: a descriptive cross-sectional study.

Objectives: This study aimed to explore the effects of removable aligners and fixed appliances on the supragingival bacterial communities in adult female patients undergoing orthodontic treatment. Methods: Supragingival plaque samples from 48 female individuals underwent microbiome analysis (16S rRNA gene sequencing) using PacBio Sequel sequencing. The study included 13 adults without orthodontic treatment needs as the control group (Group C), and 35 patients with comparable initial orthodontic conditions who received treatment at a university clinic in Beijing, China. The treatment involved either traditional fixed brackets (Group B, n = 17) or Invisalign® aligners (Group AT, n = 18). Bioinformatics methods were used for data analysis. Results: From the 48 plaque samples, a total of 334,961 valid reads were obtained, averaging 6,978 sequences per sample. The 16S rDNA sequences were classified into 25,727 amplicon sequence variants (ASVs). Significant variances in alpha and beta diversity among the groups were noted. Group B microbiome exhibited an increased presence of Gram-negative bacteria. At the phylum level, Actinobacteriota was significantly more prevalent in Group C samples, while Bacteroidota was enriched in Group B samples. Family-level relative abundance analysis showed a notable increase in Saccharibacteria (formerly TM7) and Prevotellaceae in Group B. Genus-level analysis revealed a significant rise in Lautropia in Group AT. Fixed orthodontic appliances were linked to oral microbiome changes, notably an enhanced relative abundance of anaerobes, including periodontal pathogens. Conclusion: The observation points to the impact of orthodontic appliance on the oral microbial community, highlighting the difference between traditional braces (Group B) and clear aligners (Group AT)in terms of the predominance of anaerobic and gram negative bacteria. This emphasizes the importance of considering the microbiological effects when choosing orthodontic appliance and underscores the need for tailored oral hygiene practices for individuals undergoing these treatments. This research might provide insights that could assist in the development of innovative cleaning techniques and antibacterial materials.

Effect of Different Cleaning Regimes on Biofilm Formation of Acrylic-Based Removable Orthodontic Appliance: A Randomized Clinical Trial.

Objectives: This study aimed to evaluate the effects of different cleaning regimes of acrylic-based removable orthodontic appliances on bacterial biofilm formation and whether the surface modification, i.e., polished acrylic fitting surface, reduces biofilm formation. Materials and Methods: This double-blind, parallel, randomized clinical trial involved thirty-nine orthodontic patients indicated for removable orthodontic appliances. The patients were allocated into three groups according to the cleaning method: brushing with a denture brush and chlorhexidine (CHX) toothpaste, Lacalut cleaning tablet, and a combination of both cleaning methods. Each patient wore an upper removable appliance containing eight wells fitted with eight detachable acrylic tiles (four polished and four unpolished) for seven days. Five types of oral microbiota were evaluated using selective growth media and biochemical tests. The biofilm cleaning efficacy was assessed using the colony-forming unit (CFU) and scanning electron microscopy (SEM). Statistical Analysis. Data from the CFU using different cleansing regimes were compared, following log transformation, using one-way analysis of variance (ANOVA). The polished and unpolished tiles were compared for biofilm formation on each cleansing method using an independent t-test. Results: There was no significant difference among the three cleaning methods on the polished or unpolished tiles. However, in polished tiles, streptococci were significantly reduced in all cleaning methods, whereas staphylococci and Staphylococcus aureus were markedly decreased in brushing and combination cleaning methods. However, the total number of anaerobic bacteria was significantly reduced in polished tiles using the combination method only. Conclusions: Polishing the fitting surface of an acrylic-based orthodontic appliance reduced the tested bacterial biofilm formation and may enhance cleaning efficiency. Brushing and combination methods showed superior cleaning effects compared to cleaning tablets. This trial is registered with NCT05707221.

Orthodontic Emergencies and Perspectives During and After the COVID-19 Pandemic: The Italian Experience

ABSTRACT Objective: To investigate the types of dental emergencies that occurred during the lockdown period in Italy (12th March-4th May) and to investigate future therapeutic preferences related to the use of different types of appliances. Material and Methods: A questionnaire dedicated to assessing dental emergencies during the lockdown period and surveying the resumption of orthodontic practice was submitted to clinicians in digital form. The first part of the questionnaire, focused on the orthodontic emergencies that were encountered in relation to the different types of orthodontic appliances and how these were resolved. The second part of the questionnaire was devoted to the resumption of clinical practice; in particular, it was designed to assess whether and what percentage of clinicians are willing to change the duration of appointments in relation to the different types of appliance used, asking them whether their approach to orthodontic treatment would change in the coming months as compared to the pre-COVID-19 era. Results: Results show that in most cases (82%), the percentage of patients who experienced a dental emergency was less than 5% and that far fewer emergencies were attributable to removable (5.7%) than to fixed appliances (94.3%). Looking ahead, clinicians expressed a greater preference for using removable (60.8%) rather than fixed appliances (39.2%). Conclusion: During the lockdown, there relatively few orthodontic emergencies, many of which were handled by telephone consultation. However, a far lower percentage of emergencies were generated by removable (e.g., clear aligners) as opposed to fixed appliances (e.g., multibracket equipment), likely influencing the decision of the majority of clinicians to opt for removable appliances in the wake of the COVID-19 pandemic.

Quantitative Interpretation of Hydration Dynamics Enabled the Fabrication of a Zwitterionic Antifouling Surface.

In the medical industry, zwitterionic brushes have received significant attention owing to their antifouling effect that arose from their hydration ability. However, sufficient understanding of the hydration dynamics of zwitterionic brushes is required to fabricate the precisely controlled antifouling medical devices. In this paper, we successfully show that hydration, the interaction between water molecules and zwitterionic brushes, and its dynamics can be evaluated logically and quantitatively using (i) water contact angle, (ii) molecular dynamics simulation, and (iii) Raman spectroscopy. Based on the intuitive results on hydration, we precisely optimized the antifouling property of the model medical device, a removable orthodontic retainer, with various grafting efficiencies of 2-methacryloyloxyethyl phosphate choline. As a result, the model device reduced nonspecific adsorption of proteins and bacteria, indicating an improved antifouling effect, and also inhibited the formation of a biofilm. Furthermore, the device showed excellent physical properties desirable for application in the orthodontic field, meaning the balance between the antibacterial property and mechanical strength.

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

BACKGROUND: Fixed orthodontic appliances might be associated with intraoral adverse effects on enamel, due to plaque accumulation and their colonization by oral microbes. At the same time, the demand for esthetic alternatives to orthodontic treatment, like thermoplastic aligners, is growing. However, thermoplastic aligners may behave differently intraorally than fixed appliances in terms of bacterial colonization and biofilm formation. Therefore, the aim of this prospective cohort study was to assess the salivary prevalence of the cariogenic bacteria Streptococcus mutans, Lactobacillus acidophilus, and Streptococcus sanguinis among adolescents treated orthodontically with thermoplastic aligners or fixed appliances. METHODS: Thirty adolescent patients (17 girls/13 boys; mean age 13.8 years old) were assigned to treatment with either (i) self-ligating fixed appliances with nickel-titanium archwires or (ii) aligners constructed from clear transparent polyethylenterephthalat-glycol copolyester (PET-G) thermoplastic sheets. Whole stimulated saliva was collected from each patient at three time points: at baseline (before bonding and initiation of orthodontic therapy or before insertion of the thermoplastic aligners), after 2 weeks, and after 1 month. A simplified plaque index, a simplified gingival index, and the decayed, missing, and filled teeth (DMFT) index were assessed from the clinical examination of the patients. Microbiological analysis of salivary bacteria was performed by quantitative polymerase chain reaction, followed by descriptive and inferential statistics at the 5% level. RESULTS: Although patients treated with aligners had significantly lower plaque and gingivitis scores throughout treatment compared to patients treated with fixed appliances, no significant difference could be found between the S. mutans counts of the two groups at any time through treatment (P > 0.05). On the other hand, patients treated with aligners had significantly lower salivary S. sanguinis counts at all time points than patients treated with fixed appliances (P < 0.05). Finally, almost no L. acidophilus were identified in the collected saliva samples in either of the treated samples. CONCLUSIONS: Within the limitations of this study, there were no differences in the salivary counts of S. mutans or L. acidophilus among adolescent patients treated for 1 month with thermoplastic aligners or self-ligating appliances. On the other hand, patients treated with aligners had lower salivary levels of S. sanguinis compared to those treated with self-ligating appliances.

Association between clinical and salivary microbial parameters during orthodontic treatment with removable appliances with or without use of fluoride mouth rinse.

AIM: To evaluate the correlation between clinical and salivary microbial parameters during treatment with removable orthodontic appliances with or without use of fluoride mouth rinse. MATERIALS AND METHODS: A group of 48 patients completed this randomized, controlled, parallel-group, clinical pilot study. 24 patients of the test group (TG) rinsed after tooth brushing with a fluoride mouth rinse (100 ppm AmF/150 ppm NaF) while 21 patients of the control group (CG) did not. Clinical parameters [Approximal Plaque Index (API), Papillary Bleeding Index (PBI)] as well as levels of salivary mutans streptococci (MS) and lactobacilli (LB) were assessed at baseline and after 3, 6, 9 and 12 months. Compliance was documented by participants. Appliance wear-times were estimated retrospectively by the patients. All participants received the same brushing instructions and were supplied with the same toothbrush/toothpaste. RESULTS: A significant correlation of API values with MS levels (p=0.0003) or with LB levels (p=0.001) was observed. Furthermore, appliance wear-times were significantly associated with API values (p=0.02). The changes of MS or LB levels between beginning and end of the study did not differ significantly between study groups. The changes of the API scores showed slightly different median values (-3.5 in the TG vs. 0 in the CG), the difference, however, was not significant. CONCLUSIONS: The results emphasise the need for a careful monitoring of the oral hygiene status in patients with removable orthodontic appliances. Larger controlled clinical trials are necessary to investigate treatment options such as use of supplementary fluoride mouth rinse.

Avaliação in vitro de bactérias e fungos na superfície de aparelhos ortodônticos removíveis / Evaluation in vitro of bacteria and fungi in surface removable orthodontic appliances

O acometimento do indivíduo por patologias, como a cárie e doenças periodontais, pode ser traumático e extremamente devastador, podendo levá-lo a situações de grande comprometimento da saúde bucal e sistêmica. A introdução dos aparelhos removíveis pode predispor o desenvolvimento destas de modo que, além de aumentar o número populacional destes microrganismos, induz uma grande queda do pH intrabucal, favorecendo o processo de desmineralização dos tecidos duros e agredindo concomitantemente os tecidos moles. Logo, é necessário pesquisar e entender a fixação destes na superfície de aparelhos ortodônticos. A coleta foi realizada antes e 15 dias após a instalação dos aparelhos ortodônticos removíveis na cavidade bucal, mediante um esfregaço com swab estéril, aplicando movimentos anteroposteriores sob pressão manual na região do acrílico e na região dos parafusos expansores, quando houvesse. Na coleta inicial, houve crescimento de microrganismos em 15% dos casos para o Agar Mitis Salivarius, e 5% para o Ágar Sabouraud. Já na coleta após os 15 dias de instalação, verificou-se aumento para 100% de contaminação nas placas de Agar Mitis Salivarius, e as placas de Ágar Sabouraud permaneceram com os 5% de contaminação. Um padrão de limpeza mais bem elaborado desses aparelhos deve ser praticado pelos que o utilizam, além de estar indicada a substituição do aparato após algum tempo de uso, pois a inserção do aparelho modifica o ambiente da cavidade bucal.

The involvement of the individual by diseases such as caries and periodontal disease can be traumatic and extremely devastating and can lead one to situations of great commitment of oral and systemic health. Also, the introduction of removable appliances may predispose the development of these so that in addition to increasing the population of these microorganisms, it induces a large drop in the intraoral pH value, favoring the process of demineralization of hard tissues and simultaneously attacking the soft tissue, thus it is important to research and understand the fixation of these on the surface of orthodontic appliances. Data collection was conducted prior to installation of removable orthodontic appliances and 15 days after by a swipe with a sterile swab, applying movements from front to back under manual pressure in acrylic region and the region of expander bolts. At the first exam, 15% of cases had Agar Mitis Salivarius and 5% Agar Sabouraud. Fifteen days later, all appliances were contaminated with Agar Mitis Salivarius, while only 5% of devices were contaminated with Agar Sabouraud. A detailed cleaning must be exercised over these devices, along with replacement of the orthodontic device after some period because it can change the oral environment.

Effects of Fixed and Removable Space Maintainers on Plaque Accumulation, Periodontal Health, Candidal and Enterococcus Faecalis Carriage.

OBJECTIVE: To evaluate the effects of space maintainers on plaque accumulation, periodontal health and oral microflora. SUBJECTS AND METHODS: The study participants comprised 38 patients aged 4-10 years requiring either fixed or removable space maintainers. Plaque index, gingival index, bleeding on probing index, candidal colonization and Enterococcus faecalis were recorded just before the application of space maintainers (T0) and during treatment at the 1st (T1), 3rd (T2) and 6th (T3) month. RESULTS: The gingival and bleeding on probing index scores increased significantly (gingival index from 0.20 ± 0254 to 0.54 ± 0417 and bleeding on probing index from 7.18 ± 9.946 to 18.07 ± 14.074) in the regions with fixed space maintainers at T3 (p < 0.01). The mean Candida counts also increased (for removable appliances from 1.90 ± 3.638 to 1.98 ± 3.318, p < 0.05, and for fixed appliances from 4.25 ± 4.587 to 4.52 ± 4.431, p < 0.001). The salivary E. faecalis counts at T3 also increased significantly with the use of fixed and removable appliances (for removable appliances from 5.93 ± 2.65 to 85.53 ± 34.1 and for fixed appliances from 4.95 ± 2.94 to 123.59 ± 29.51, p < 0.001). A positive correlation was found between the plaque (r = 0.67), gingival (r = 0.76) and bleeding on probing index scores (r = 0.76) and the candidal colonization for the fixed space maintainers (p < 0.01, p < 0.001). CONCLUSIONS: In this study, both fixed and removable space maintainers led to an increase in the number of microorganisms in the oral cavity as well as to increases in the periodontal index scores. Patients should be informed that space maintainers may serve as a source of infection and that special attention must be given to their oral hygiene.

Efficacy of cleaning tablets for removable orthodontic appliances: an in vivo pilot study.

OBJECTIVES: The purpose of this study was to test the cleaning effect of three commercially available effervescent tablet products on acrylic resin surfaces compared to water as control medium. METHODS: A total of 20 volunteers were instructed to wear a vacuum-formed maxillary splint continuously for 96 h. Each splint incorporated four resin discs in the palate area. Each of these PMMA (polymethyl methacrylate) discs was split into two specimens which were analyzed upon removing the splint after the 4-day period. One specimen per disc was analyzed uncleaned and one after cleaning, using one of the investigated tablet products according to the manufacturer's recommendations or water as control medium. The outcomes of cleaning were evaluated with the modified ortho-phthaldialdehyde (OPA) method by determining the amounts of surface protein. RESULTS: Significant differences in relative (%) protein removal were noted between all three tablet products and water, and fittydent super® was significantly more effective in removing biofilm than Kukis®. No significant differences were observed between fittydent super® and NitrAdine® Ortho&Junior™ or NitrAdine® Ortho&Junior™ and Kukis®. CONCLUSION: The modified OPA method proved to be successful in examining protein-containing contaminations on the specimens, and the effervescent products tested were more effective than pure water in removing contaminants from orthodontic appliances. These results are, however, confined to soft plaque not older than 4 days.

Candida spp. adherence to oral epithelial cells and levels of IgA in children with orthodontic appliances.

Adhesion and colonization of the oral cavity by Candida albicans is an initial step in candidosis. Orthodontic and other oral appliances seem to favor candidal presence. The aim of this work was to compare the presence of Candida species in saliva, their adherence to oral epithelial cells, and the levels of anti­C. albicans IgA in children with or without orthodontic appliances. This study included 30 children 5 to 12 years old (9.1 ± 1.7 years old) who were users of removable orthodontic devices for at least 6 months and 30 control children of similar ages (7.7 ± 1.5 years old). The presence of yeast species in the saliva was evaluated by microbiological methods. Candida species were identified using phenotypic methods. Anti­C. albicans IgA levels in saliva were analyzed by ELISA. The yeasts adhering to oral epithelial cells were assessed by exfoliative cytology. No statistically significant differences were observed for saliva yeast counts and anti­C. albicans IgA levels between the studied groups. Children with orthodontic devices exhibited more yeast cells adhering to oral epithelial cells and a higher percentage of non-albicans species relative to the control group. In conclusion, orthodontic appliances may favor the adherence of Candida to epithelial cells but do not influence the presence of these yeasts in saliva, and the levels of anti­C. albicans IgA do not correlate with yeast adherence or presence of Candida in the oral cavity

Candida spp. adherence to oral epithelial cells and levels of IgA in children with orthodontic appliances

Adhesion and colonization of the oral cavity by Candida albicans is an initial step in candidosis. Orthodontic and other oral appliances seem to favor candidal presence. The aim of this work was to compare the presence of Candida species in saliva, their adherence to oral epithelial cells, and the levels of anti-C. albicans IgA in children with or without orthodontic appliances. This study included 30 children 5 to 12 years old (9.1 ± 1.7 years old) who were users of removable orthodontic devices for at least 6 months and 30 control children of similar ages (7.7 ± 1.5 years old). The presence of yeast species in the saliva was evaluated by microbiological methods. Candida species were identified using phenotypic methods. Anti-C. albicans IgA levels in saliva were analyzed by ELISA. The yeasts adhering to oral epithelial cells were assessed by exfoliative cytology. No statistically significant differences were observed for saliva yeast counts and anti-C. albicans IgA levels between the studied groups. Children with orthodontic devices exhibited more yeast cells adhering to oral epithelial cells and a higher percentage of non-albicans species relative to the control group. In conclusion, orthodontic appliances may favor the adherence of Candida to epithelial cells but do not influence the presence of these yeasts in saliva, and the levels of anti-C. albicans IgA do not correlate with yeast adherence or presence of Candida in the oral cavity.

Efficacy of three hygienic protocols in reducing biofilm adherence to removable thermoplastic appliance.

OBJECTIVES: To examine the ability of a removable thermoplastic appliance (RTA) to adsorb hygienic solutions and inhibit bacterial growth and to examine the efficacy of three hygiene protocols in reducing bacterial biofilm adherence to RTA. MATERIALS AND METHODS: Solution adsorption and bacterial growth inhibition were examined in vitro using paper vs RTA discs. Subsequently, 11 patients treated with RTA (mean age, 29.1 ± 4.7 years) were assigned into a sequence of three hygiene protocols: regular RTA brushing (baseline), immersion RTAs in chlorhexidine mouthwash (CHX), and using a vibrating bath with cleaning solution (VBC). For each patient, 12 upper RTAs were examined (2 baseline RTAs, 5 CHX RTAs, and 5 VBC RTAs), for a total of 132 RTAs. All RTAs were stained with gentian violet, and biofilm presence was measured using a photodensitometer. RESULTS: The RTA discs did not adsorb CHX or cleaning solution. The later agent did not show antibacterial features. Baseline RTAs showed significant biofilm adherence (P < .001) on the posterior palatal side of the aligner and on the anterior incisal edge. CHX and VBC hygienic protocols significantly (P < .001) reduced baseline biofilm adherence by 16% and 50%, respectively. Hygienic improvement was maintained over 140 days when CHX and VBC were used. However, VBC was three times more efficient than CHX. CONCLUSIONS: This study highly recommends the use of a VBC protocol. Biofilm deposits on the RTA, especially on incisal edges and attachment dimples, could lead to inadequate tooth/RTA and attachment/RTA overlap and consequently impair tooth alignment.

Biofilm associated microorganisms on removable oral orthodontic appliances in children in the mixed dentition.

OBJECTIVE: Biofilms on removable orthodontic appliances act as reservoir of microorganisms, capable of modifying the environmental condition of oral cavity and are difficult to be removed with routine hygiene measures. The present investigation includes enumeration, identification and numerical analysis of different types of cultivable bacteria associated with the biofilms on removable orthodontic appliances. STUDY DESIGN: Removable appliances of 25 healthy children among the ages of 10 to 14 years were taken to measure the prevalence of biofilms and type of microorganisms. For isolation of microorganism from biofilms different types of selective and non-selective medium based on standard methods were used. The data were further analysed by using Kolmogorov-Smirnov test, one-sample t-test and Spearman rank correlation coefficient. The percentage frequencies of isolates were also calculated RESULTS: The survey revealed the presence of both multi-species and mono species biofilms on appliances, with Non-Streptococci, anaerobic bacteria, Streptococcus spp., members of the family Enterobacteriaceae and Lactobacillus spp. as a dominant microbial flora of biofilms. Bacillus sp. and Candida sp. were isolated from one sample each. Significant positive and negative correlations were established among the species isolated from biofilms. CONCLUSION: Higher prevalence of the members of the family Enterobacteriaceae were reported during this study, advocating an extra hygienic measure is essential for this age group while wearing acrylic orthodontic appliances in oral cavity.

Effect of microbubbled water on the removal of a biofilm attached to orthodontic appliances--an in vitro study.

Orthodontic appliances often cause oral diseases such as dental caries and gingivitis due to the attachment of an oral biofilm. However, there are few reliable methods to remove the biofilm from the orthodontic appliances. The aim of this study was to investigate the effects of microbubbled water on the removal of biofilms made with Streptococcus mutans or Candida albicans on orthodontic appliances. The orthodontic appliances with biofilm were immersed with microbubbled water and the remaining biofilm on the appliances was detected and measured using a micro-plate reader and an absorbance meter. The microbubbled water had a sufficient effect on the removal of biofilm from orthodontic appliances. The effects of microbubbled water were significantly higher than those of tap water (S. mutans: p<0.05, C. albicans: p<0.01). The results of this study suggest that microbubbled water is effective in the removal of biofilm from the mouth of orthodontic patients.

An ORMOSIL-containing orthodontic acrylic resin with concomitant improvements in antimicrobial and fracture toughness properties.

Global increase in patients seeking orthodontic treatment creates a demand for the use of acrylic resins in removable appliances and retainers. Orthodontic removable appliance wearers have a higher risk of oral infections that are caused by the formation of bacterial and fungal biofilms on the appliance surface. Here, we present the synthetic route for an antibacterial and antifungal organically-modified silicate (ORMOSIL) that has multiple methacryloloxy functionalities attached to a siloxane backbone (quaternary ammonium methacryloxy silicate, or QAMS). By dissolving the water-insoluble, rubbery ORMOSIL in methyl methacrylate, QAMS may be copolymerized with polymethyl methacrylate, and covalently incorporated in the pressure-processed acrylic resin. The latter demonstrated a predominantly contact-killing effect on Streptococcus mutans ATCC 36558 and Actinomyces naselundii ATCC 12104 biofilms, while inhibiting adhesion of Candida albicans ATCC 90028 on the acrylic surface. Apart from its favorable antimicrobial activities, QAMS-containing acrylic resins exhibited decreased water wettability and improved toughness, without adversely affecting the flexural strength and modulus, water sorption and solubility, when compared with QAMS-free acrylic resin. The covalently bound, antimicrobial orthodontic acrylic resin with improved toughness represents advancement over other experimental antimicrobial acrylic resin formulations, in its potential to simultaneously prevent oral infections during appliance wear, and improve the fracture resistance of those appliances.

The effect of NitrAdine on the Candida levels of maxillary removable appliances.

OBJECTIVE: Candida colonization is a consequence of orthodontic treatment and can lead to oral candidosis as a complication of maxillary removable appliance treatment. During orthodontic treatment, it is important to minimize colonization to prevent active infection that could consequently interfere with treatment. Hygiene is the most important factor in managing colonization; in this study, the efficacy of NitrAdine to reduce Candida was tested. METHOD AND MATERIALS: A randomized, double-blind, placebo-controlled trial was performed. Ninety-two patients 11 to 14 years of age were recruited at the Children's and the University Dental Clinics at Mater Dei Hospital, Tal-Qroqq, Msida, Malta. Forty-four patients used the product with NitrAdine, while 48 patients used a placebo. Sampling employing the imprint technique was performed before and after the product was used. Brilliance Candida agar was used for cultures and identification. Further identification was performed using Auxacolor 2 when required. RESULTS: The control group had a statistically significant increase in Candida during treatment, while the experimental group had a nonstatistically significant decrease. CONCLUSION: It was concluded that NitrAdine may reduce the Candida burden in maxillary removable appliances. Larger sample sizes are needed to achieve statistical significance.

Cleaning removable orthodontic appliances: a survey.

OBJECTIVE: The aim of this survey was to analyze the recommendations commonly followed in Germany for cleaning removable orthodontic appliances (ROAs) and to compare these with published procedures. METHODS: A total of 450 randomly-selected orthodontists were contacted by telephone and asked for their recommendations for cleaning ROA. RESULTS: The most frequent recommendation was mechanical cleaning with a toothbrush (99.8%). Chemical detergents (37.1%) and treatment with diluted vinegar or citric acid (30.5%) were mentioned less often. CONCLUSION: The use of cleaning solutions was recommended comparatively infrequently, even though the scientific literature suggests that this is the most hygienic way to care for ROA.

Evaluation of home disinfection protocols for acrylic baseplates of removable orthodontic appliances: A randomized clinical investigation.

INTRODUCTION: In this randomized clinical trial, we investigated, using the microbial culture technique and scanning electron microscopy, the contamination of acrylic baseplates of removable orthodontic appliances by mutans streptococci (MS) and evaluated the efficacy of different home disinfection protocols with a 0.12% chlorhexidine gluconate spray (Periogard, Colgate-Palmolive, São Bernardo do Campo, Brazil). METHODS: Fifteen dental students were randomly enrolled in a 3-stage changeover system with a 1-week interval between each stage. The acrylic baseplates were worn full time except at meals to simulate the routine use of removable appliances under clinical conditions. Three 1-week home disinfection protocols were tested in all stages by a different group of students: protocol I, toothbrushing + baseplate brushing + sterile tap water spraying once a day; protocol II, toothbrushing + baseplate brushing + Periogard spraying on the seventh day after appliance placement; and protocol III, toothbrushing + baseplate brushing + Periogard spraying on the fourth and seventh days after appliance placement. After the first week, the volunteers received new baseplates, toothbrushes, and dentifrices, and the regimens were repeated 2 more times. At the end of each week, the baseplates had a randomized disinfection protocol and were sent for microbiologic analysis. A scanning electron microscope was used to examine 3 acrylic baseplates representing each home protocol. The Friedman test (α = 0.05) compared the home protocols for the formation of MS colonies or biofilms on the acrylic surfaces. RESULTS: MS colonies or biofilms were found on all acrylic baseplates after protocol I. Protocols II and III reduced significantly (P <0.05) the number of MS colonies and biofilms on the acrylic surfaces. No significant difference (P >0.05) was observed between protocols II and III. The scanning electron microscope analysis confirmed the results of the microbiologic cultures. CONCLUSIONS: Disinfection of baseplates of removable orthodontic appliances by using 0.12% chlorhexidine spray once or twice a week reduced the contamination by MS on the acrylic surface in vivo.