1. bookVolume 38 (2022): Issue 1 (January 2022)
Journal Details
License
Format
Journal
eISSN
2207-7480
First Published
01 May 1967
Publication timeframe
1 time per year
Languages
English
Open Access

The effect of orthodontic appliances on the Oral Candida colonisation: a systematic review

Published Online: 14 Mar 2022
Volume & Issue: Volume 38 (2022) - Issue 1 (January 2022)
Page range: 51 - 62
Received: 01 Nov 2021
Accepted: 01 Jan 2022
Journal Details
License
Format
Journal
eISSN
2207-7480
First Published
01 May 1967
Publication timeframe
1 time per year
Languages
English
Introduction
Background

Candida species is a commensal yeast that colonises the oropharyngeal region of more than 60% of healthy subjects without resulting in clinical symptoms of infection.1 Oral candidiasis is a common opportunistic infection of the oral cavity caused by an overgrowth of the Candida species, the most common being Candida albicans.2 The ability of Candida to become a pathogenic microorganism is determined by risk factors, including systemic diseases (diabetes or infection) and local factors (orthodontic appliances, removable dentures and poor oral hygiene).2 The onset of candidiasis represents a serious clinical problem, especially in immune-compromised patients,3 because the infection can spread via the vascular route or upper gastrointestinal tract and lead to severe systemic infection.2 Due to an increase in the use of corticosteroid and immuno-suppressive therapies as well as the improved survival of certain diseases (such as AIDS), an increasing number of immune-compromised patients present for orthodontic treatment, along with their healthy peers.3 Moreover, the number of children diagnosed with cancer is increasing and the greater efficacy of children's oncological treatment has globally increased the number of cancer survivors.4 Therefore, the number of oncological children or adolescents seeking orthodontic treatment is also increasing3 and attention must be paid to the possible complications that orthodontic treatment could induce in immuno-compromised patients5 as it has been shown that orthodontic appliances (fixed and removable) could promote changes in the oral microbiota.6 A Fixed Orthodontic Appliance (FOA) is the most common treatment method used in contemporary orthodontics.7 Its complex design based on the fixed placement of brackets and bands can affect oral hygiene practices, thereby promoting the accumulation of dental plaque and altering saliva properties and microbial counts.8 A Removable Orthodontic Appliance (ROA) is another common device used to move or retain teeth during or after orthodontic treatment.9 Because these acrylic appliances cover a large area of mucosa for extended periods, the prolonged wear of an ROA reduces salivary flow and pH levels, protects the microbiome from the natural flow of saliva and the mechanical removal effects of the oral musculature.9 Published literature has shown that these variables would possibly lead to pathogenic Candida colonisation, especially if there are favourable conditions and a reduction in immune function.3 However, the effect of orthodontic treatment by fixed and/or removable appliances on Candida colonisation has not been assessed in an evidence-based manner. The only existing systematic review of treatment-induced Candida changes assessed few databases and found a limited number of studies.3

Therefore, the evaluation of the effects of orthodontic treatment on oral Candida status is helpful for clinicians to decide the most appropriate and individualised treatment based on the patient's clinical conditions, especially in susceptible patients who might have a high risk of local or systemic complications.10

Therefore, the aim of this review was to evaluate if orthodontic appliances induce changes in Candida colonisation in order to answer the following questions:

Does an orthodontic appliance affect the number and the composition of Candida colonies in the oral cavity?

Are there any differences in Candida populations related to FOA and ROA?

Material and methods
Protocol

This systematic review was performed according to the PRISMA statement.11

Eligibility criteria

According to Participants-Intervention-Comparison-Outcome-Study design schema (PICOS), the inclusion and exclusion criteria are summarised in Table I.

List of inclusion and exclusion criteria.

Field Inclusion Exclusion
Patients Children, adolescents or young adults (<25 years) of any sex, ethnicity and malocclusion, in general good health Adults (>25 years)In vitro studiesAnimal studies
Intervention (exposure) Orthodontic treatment with any vestibular fixed appliance (metal or ceramic, conventionally-ligated or self-ligated) or any removable appliances Patients not receiving orthodontic treatmentPatients receiving orthodontic treatment without specific descriptions of the materials and applied techniquePatients receiving partial appliancesPatients receiving or having received systemic antibiotic treatment less than a month before or during orthodontic treatmentSmoking patients
Comparison A. No comparison (For the descriptive analysis of Candida changes in treated patients)B. Ortho-tx vs no-tx (Comparison between treated and non treated patients)C. Ortho-tx vs ortho-tx (Comparison between ROA and FOA)
Outcome Quantitative and qualitative analysis of Candida colonies, from intra-oral mucosal sites, saliva or supra/sub-gingival plaque.All available time-points will be included and categorized into pre-treatment, short-term (< 3 months) treatment, mid-term (3–6 months) treatment and long-term (< 6 months) treatment, post-treatment No clear mention of the analysis or time-point
Study design Randomized clinical trials or non-randomized, prospective or retrospective, cohort studies

Note: Tx, treatment; ROA, removable orthodontic appliance; FOA, fixed orthodontic appliance.

Information sources and literature search

The search for articles was carried out using four electronic databases (Pubmed, Scopus, Web of Knowledge, CENTRAL), and included publications in the English language from inception up to September 2021. Human studies which featured the keywords “orthodontic” OR “orthodontics” OR “fixed appliance” OR “removable appliance” OR “bracket” OR “removable aligner” AND “Candida” OR “Candidiasis” OR “Candidosis”, were identified. In addition, the reference and citation lists of the included trials and relevant reviews were manually searched.

Study selection

All titles identified from the literature were screened and selected by two independent authors (A.C.; E.L.M.). Duplicate studies were eliminated. The abstracts were examined and full texts were obtained if additional data were needed to fulfil the eligibility criteria. Conflicts were resolved by discussion with a third author (L.L.M.).

Data collection

The characteristics of the included studies (study design, patients, age, orthodontic appliance, sample site, timing, analysis method, outcome, additional measures, quality of the study) were independently extracted by two authors (A.C.; E.L.M.). For further clarification, missing or unclear information was directly requested of the respective authors.

Methodological quality assessment

The methodological quality of the included studies was assessed according to the “Swedish Council on Technology Assessment in Health Care Criteria for Grading Assessed Studies” (SBU) method.12 Articles were ranked into three levels (A, B, C) of evidence (Table II) and, based on the score assigned to each study, the review level of available evidence was further scored into four grades (1,2,3,4) (Table III).

Swedish council on technology assessment in health-care (SBU) criteria for grading assessed studies.

SBU criteria for grading assessed studies
Grade A (High level of evidence)Randomized clinical study or prospective study with a well-defined control group, defined diagnosis and endpoints, diagnostic reliability tests and reproducibility tests described
Grade B (Moderate level of evidence)Cohort study or retrospective case series with defined control or reference group, defined diagnosis and endpoints, diagnostic reliability tests and reproducibility tests described
Grade C (Low level of evidence)Large attrition, unclear diagnosis and endpoints, poorly defined patient material

Definitions of evidence level.

Level Evidence Definition
1 Strong At least two studies assessed with level “A”
2 Moderate One study with level “A” and at least two studies with level “B”
3 Limited At least two studies with level “B”
4 Inconclusive Fewer than two studies with level “B”
Data synthesis

Due to the lack of homogeneity in the study setting (study design, sample site, sample collection time and methods), only a systematic review could be conducted rather than a meta-analysis.

Results
Study selection

The initial search identified 533 articles from Pubmed, Scopus and Web of Knowledge. After eliminating duplicates and ineligible studies by title and abstract, a total of 157 full texts were screened. Finally, a total of sixteen papers were identified according to the eligibility criteria.

The flow chart of the selection of eligible studies for this review is summarised in Figure 1.

Figure 1

Flow diagram of the included studies according to the PRISMA.

Assessment of methodological quality

According to the SBU tool, the quality of evidence for nine studies was moderate (grade B) and for seven studies was low (grade C). As a result, the level of evidence for the conclusions of this review was considered limited (level 3).

Study characteristics

The characteristics of the studies are presented in Table IV. Of the 16 included studies, all were prospective in nature and included four reports which described the changes in Candida in patients treated using a ROA13,17,20,26 and nine studies which described those treated with FOA.8,14,15,16,21,22,23,24,27 Three studies analysed and compared treated and non-treated patients, two of which involved a ROA17,18 and one used FOA25. An additional untreated group served as a control. Only one study compared the changes in candida between ROA and FOA therapies.19

Characteristics of the studies.

No. Study ID/ Design Patients (M/F) Agea Appliance Sample site Timing Analysis method Outcome Additional measures Quality of the study
1 Arendorf 198513 Prospective Exp: 33 (15/18) 8–17 y ROA Six mucosal site (ant and post palate, ant and post tongue, r and l cheek) T0 = before AppInsT1 = during therapyT2 = after AppRem (after average 9 mos) Imprint Culture (Arendorf and Walker technique) Prevalence (%) Density PI + saliv pH C
2 Hägg 200414 Prospective Exp: 27 (13/14) 15.5 + 2.3 y FOA Rinse Dorsum of the tongue Supra and subgingival plaque T0=before AppInsT1 = 1 mos after T0T2 = 2 mos after T0T3 = 3 mos after T0 Oral Rinse (Samaranayake technique) Imprint Culture (Arendorf and Walker technique) (SDA, Gram stain, germ tube test, API 20 C AUX) Pooled Plaque Prevalence (%)Density (CFU)Species composition PI + count of Enterobacteriaceae + total bacterial count B
3 Arslan 200815 Prospective Exp 1: 72Exp 2: 42 (19/23) Candida carriers out of 72 subjects, that were treated 19.8 y FOA (metal brackets) Dorsum of the tongue (only for T0)Mid-palate (only for T0)SalivaU5/L5U1/L1 T0 = before AppInsT1 = 1 mos after T0T2 = 6 mos after T0T3 = 12 mos after T0 Swab Culture (Kleinegger method, SDA)Salivary culture (SDA, Gram staining, germ-tube test, chlamydospore, API 20C AUX system))Pooled plaque (SDA) Prevalence (%)Density (CFU)Species composition None B
4 Lee 200816 Prospective Exp: 97 (38/59) 17.7 y FOA Rinse From T0 = before AppIns to T10 = 12 mos after T0 Oral rinse technique (Samaranayake technique, SDA)Phenotypic methods (germ-tube test; API ID 32C)Genotypic methods (RAPD analysis)Dendogram analysis Prevalence (%)Species composition None C
5 Mahmoudadabi 200917 Prospective Exp 1: 34Exp 2: 34 13 y (Exp 1)12.5 y (Exp 2) ROA (upper) Cr Saliva Surface of upper appliance (not considered) T0 = before AppInsT1 = over 8 mos after T0 Culture (Arendorf and Walker, Davenport techiques) (CHROMagar; germ-tube test) Prevalence (%)Count (CFU)Species composition None C
6 Gonçalves e Silva 201418 Prospective Exp 1: 30Exp 2: 30 9.1+−1.7 (Exp 1)7.7+−1.5 (Exp 2) ROA Cr Cheek and lateral surface of the tongue Saliva T0 = before AppInsT1 = at least 6 mos after T0 Culture (SDA; CHROMagar) Phenotypic methods Exfoliative cytology Prevalence (%)Count (CFU)Species composition Counts of Anti-C.albicansIgA B
7 Arab 20168 Prospective Exp 1: 30 (6/24) 12–18 y FOA Saliva T0 = before AppInsT1 = 6 we after T0T2 = 12 we after T0T3 = 18 we after T0 Culture (SDA) Count (CFU) Salivary flow and pH Microbial counts (S. mutans/L. acidophilus) C
8 Khanpayeh 201419 Prospective Exp 1: 40Exp 2: 40 (35/45) 7–18 y FOA (metal) ROA Unstimulated saliva T0 = before AppInsT1 = 6 mos after T0 Culture (SDA; Germ-tube test; corn meal agar)Biochemical tests (API 20C method) Frequency (%)Species composition None B
9 Kundu 201620 Prospective Exp 1: 10Exp 2: 10 (not considered) 6–15 y ROA Fixed space maintainers (nc) Unstimulated saliva T0 = before AppInsT1 = 1 mo after T0T2 = 3 mos after T0T3 = 6 mos after T0 Culture (SDA) Count (CFU) Bacterial count (S. mutans and Lactobacillussp.) B
10 Zheng 201621 Prospective Exp 1: 50 (23/27) 10–18 (13.6 y) FOA Gargle T0 = before AppInsT1 = 1 mo after T0T2 = 2 mos after T0T3 = 3 mos after T0T4 = 6 mos after T0 Culture (CHROMagar)PCR (Tiangen Biotech) Incidence (%)Count (CFU)Species composition None B
11 Shukla 201722 Prospective Exp 1: 60 16–18 y FOA Buccal and labial Plaque of anterior teeth and U6 + L6 T0 = before AppInsT1 = 2 mo after T0T2 = 3 mos after T0 Swab Culture (SDA; Gram stain; germ tube test, counts in CFU) Count (CFU) S. mutans B
12 Grzegocka 202023 Prospective Exp 1: 17 (6M/11) 17+−7 y FOA Oral rinse Elastomeric rings (nc) T0 = before AppInsT1 = 2 we after T0T2 = 6 we after T0T3 = 12 we after T0 Culture (Dalmau plate technique)Biochemical tests (API 20C AUX) Prevalence (%)Count(CFU) Species composition APIGBIBiofilm formation C
13 Sanz-Orrio-Soler 202024 Prospective Controlled Trial Exp 1: 124 (43/80) 19.5 y FOA (metal or ceramic) U and L vestibule T0 = before AppInsT1 = 1 mo after T0T2 = 6 mos after T0T3 = 12 mos after T0T4 = 6 mos after Swab Culture (CHROMagar plates, Becton Dickinson) Frequency (%)Species composition Questionnaire about hygiene habits B
14 Pellissari 202125 Prospective Exp 1: 23 (7/10)Exp 2: 6 (2/4) 20.7+− 8.7 y (Exp 1)19.6+−1.3 y (Exp 2) FOACr Biofilm around bck From 3 to 6 mos after AppIns Culture Biochemical tests (VITEK 2 compact system) Prevalence (%)Species composition Fungal strains and resistance to Antifungals Bacterial strains and resistance to Antimicrobials B
15 Rodríguez Rentería 202126 Prospective Exp 1: 55 (34/21) 8.4 y ROA Support oral mucosa Surface of ROA (not considered) T0 = before AppInsT1 = 4 we after T0 Chromogenic culture (ID 32 C AUX system) Frequency (%)Species composition Microbial species (Str.aureus, P.aeruginosa) C
16 Kouvelis 202127 Prospective Exp 1: 30 (17/13) 13.97 +− 2.07 FOA Saliva T0 = before AppInsT1 = 4 we after T0T1 = 12 we after T0 Culture Count Salivary pH, flow rate, buffering capacityOther microbial species C

Note:

Patient ages are reported as means (one value) or if no mean is available as range (two values in parentheses). Exp, experimental group; Cr, control group; ROA, removable orthodontic appliance; FOA, fixed orthodontic; nc, not considered in this study; %, percentage; CFU, colony forming unit; PI, plaque index; saliv pH, salivary pH; API, Approximal Plaque Index; GBI, Gingival Bleeding Index; We, week; mo, month; y, years; AppIns, appliance insertion; AppRem, appliance removal; bck, brackets; Ant, anterior; post, posterior; r, right; l, left; U, upper; L, lower; U5, upper second premolar; L5, lower second premolar; U1, upper central incisors, L1, lower central incisors; U6, upper first molars; L6, lower first molars; SDA, Sabouraud's dextrose agar; PCR, Polimerase Chain Reaction; RAPD, Random Amplification of Polymorphic DNA.

Results of individual studies

The results are summarised in Figure 1.

Primary outcome
Short-term (<3 months) Candida changes

Two studies20,26 described the short-term changes occurring during ROA treatment; eight studies8,14,15,21,22,23,24,27 analysed the effects related to FOA therapy. From baseline to one month of ROA therapy, a significant increase (p < 0.001) in the number of Candida albicans counts was observed in saliva20 and on the oral mucosa.26 During the early stages of FOA, Hägg et al.14 found a significant Candida increase on the dorsum of the tongue (p < 0.001), but not in saliva and plaque samples. Arslan et al.15 reported an increase in the number of colony-forming units (CFU) was statistically significant (p < 0.001) both in saliva and on tooth surfaces. This was confirmed by the salivary results (p < 0.001) of Arab et al.8 and by a plaque analysis (p < 0.05) conducted by Shukla et al.22 Zheng et al.21 also reported a significant increase of Candida counts (p < 0.001) in gargled samples, finding a higher (p < 0.05) percentage of Candida carriers after 2 months of FOA, compared to pre-treatment. Different results were reported by Lee et al.16 and Grzegocka et al.,23 who determined a non-significant increase of Candida, after analysing saliva samples. In addition, Soler et al.24 found no significant differences at the vestibular level, while Kouvelis et al.27 reported that Candida was not identified in any sample before and after 4 weeks of FOA.

Mid-term (3–6 months) Candida changes

One study20 reported the mid-term effects of ROA treatment and found a significant increase (p < 0.001) in the Candida counts in saliva after 3 months. Seven studies8,14,16,21,22,23,27 analysed the mid-term effects after FOA placement. Hägg et al.14 found a significant increase in candida on the dorsum of the tongue, but not in saliva and plaque samples. However, Lee et al.16 reported a significant increase in the presence of candida in saliva. Zheng et al.21 also showed that the presence of Candida was significantly higher after 3 months of FOA treatment compared to baseline, finding a significant increase (p < 0.05) of Candida counts in a gargled sample. The increase was confirmed by Arab et al.8 and Shukla et al.22 who analysed saliva and dental plaque, respectively. Grzegocka et al.23 showed a non-significant upward trend of yeast numbers in saliva after 12 weeks of FOA treatment. Only one study25 analysed the differences in candida between FOA and untreated patients suggesting that, 3–6 months after FOA placement, Candida was a frequently isolated species (12%) in orthodontic patients compared to a control group, and that, in the mid-term, the frequency of Candida significantly increased in FOA patients, compared to untreated cases.

Long-term (> = 6 months) Candida changes

One study20 investigated the long-term Candida changes in patients treated with ROA, and observed a significant increase of Candida counts (p < 0.001) in saliva after 6 months. Two studies17,18 compared Candida counts between ROA and control groups, and found conflicting results. Mahmoudababi et al.17 reported the prevalence of the salivary colonisation of Candida spp. was significantly higher (p < 0.001) in ROA patients, compared to untreated subjects. Gonçalves et al.18 observed no statistically significant differences in saliva yeast counts between the ROA and a control group. A further study19 compared the differences between two orthodontic groups, one treated with ROA and one with FOA, through an analysis of the salivary samples of 80 subjects (40 for each group). A statistical significance (p < 0.001) was found in an increased colonisation of Candida in patients treated using FOA, compared to those treated with a ROA.19 Four studies15,16,21,24 analysed the alteration in candida counts in patients treated with FOA. In comparing pre-treatment and long-term values, Arslan et al.15 found a significant increase (p < 0.001) of Candida in saliva and tooth samples, although the increase was not significant during the 6 to 12 month period. Lee et al.16 also observed significant differences (p < 0.005) in the presence of oral Candida in the saliva of FOA patients, at long-term follow-up. Alternative results were reported by Zheng et al.21 in which, after 6 months, the candida levels were comparable with those prior to treatment. In addition, Sanz-Orrio-Soler et al.24 observed no statistical difference in the frequency of Candida over the long-term.

Candida changes after orthodontic appliance removal

Two studies evaluated the differences in Candida counts before and after ROA13 and FOA24 treatment. Arendorf et al.13 observed a significant decrease in candida (p < 0.001) to baseline levels after ROA removal, although a transient significant increase (p < 0.001) occurred during therapy, especially on the posterior (63.6%) and anterior palate (60.6%). Sanz-Orrio-Soler et al.23, reported no statistically significant increase in Candida colonisation during FOA treatment. The slight increase in Candida levels from pre-treatment (T0 = 3.2%) to post-treatment (T4 = 4.8%) was not significant. Moreover, no significant differences in the presence of Candida were found between the two different analysed fixed appliances (metal or ceramic brackets).24

Candida species changes during orthodontic treatment

Eleven studies described the changes in the frequency of the different candida strains during orthodontic treatment using a ROA17,18,19,26 and FOA.14,15,16,21,23,24,25 Mahmoudabi et al.17 observed that C. albicans was the most prevalent species isolated from saliva in ROA patients (35.3%) and in control patients (26.5%), but a wider variety of Candida species were associated with ROA (30.8%), compared to controls (9.1%). Six yeast species (C. parapsilosis, famata, sake, glabrata, dubliniensis, S. cerevisiae, P. etchellsii) were isolated only in the ROA group. Gonçalves et al.18 also found a higher incidence of non-albicans Candida in the ROA group (55.2%) compared to a control group (42.9%), such as C. Iusitaniae (10.3%/4.8%), C. krusei (10.3%/0), C. Tropicalis (13.3%/9.5%), C. parapsilosis (6.9%/4.8%). Rodríguez-Rentería et al.26 noted that, after 4 weeks of ROA treatment, C. albicans and C. glabrata were the most prevalent species. Hägg et al.14 found that the predominant Candida species isolated during the first stages of FOA treatment was C. albicans (83–87%), while C. parapsilosis, C. tropicalis and C. guillermondii were less common. Arslan et al.15 found that the 58.5% (42 of the 72 patients) of an initial FOA group were Candida carriers and the most common species identified was Candida albicans (73.8%), followed by C. tropicalis, C. krusei and C. kefyr (7.14%) and by C. parapsilosis (4.76%). No long-term qualitative evaluation was carried out. Lee et al.16 observed that C. albicans was the most isolated species, while the non-albicans species identified were: C. tropicalis (4 isolates), C. parapsilosis (2 isolates), S. cerevisiae (2 isolates), C. globosa (1 isolate). Zheng et al.21 evaluated the Candida strains in a long-term follow-up, and determined that the presence of C. albicans was 85.7% of that at T0, which subsequently further decreased during treatment in favour of an increase in other strains, specifically C. parapsilosis, C. krusei and C. tropicalis. Grzegocka et al.23 identified that 58.8% of subjects were Candida-carriers (two were colonised after bracket placement), with a predominant colonisation of C. albicans (91.1%), followed by C. tropicalis (4.5%) and C. guillermondii (4.5%). Soler et al.24 reported that the most isolated candida strains in FOA patients were C. albicans, while C. glabrata and C. krusei were each found in one patient out of 124, respectively. Pellisari et al.25 observed that, in patients treated with FOA, the isolated fungal strains were C. albicans and C. krusei, compared to untreated subjects. Khanpayeh et al.19 noted a higher frequency of salivary Candida carriers (p = 0.0001) and a higher colonisation of non-albicans Candida species (p = 0.001) in a FOA group compared to a ROA sample (p = 0.0001). The negative saliva culture was 22.5% in ROA patients but only 5% in FOA patients. The most frequent species in the ROA group was C. albicans (62.5%), while in the FOA group, the frequency of C. albicans was lower (45%). The frequencies of other species were also higher in the FOA than the ROA group (C. tropicalis (FOA/ROA = 20%/7.5%), C. parapsilosis (15%/5%), C. Krusei (10%/2.5%), C. Kefyr (5%/0%)).

Discussion

Candida yeasts are able to form a biofilm on abiotic surfaces, such as the brackets of FOA or the acrylic surfaces of ROA, leading to an increased oral Candida presence to produce pathogenic oral mycoses, especially in immunodeficient patients.23 A recent review28 revealed a strong relationship between orthodontic treatment and the oral colonisation of Candida species.

Candida counts and orthodontic treatment: summary of evidence

Arendorf et al.13 suggested that ROA may initiate a Candida carrier state by inducing a significant, although transient, increase in Candida colonisation, especially on the palate. According to several studies, an incremental change was found in the Candida counts during ROA therapy, from short20,26 to a long-term period.20 These results agree with previous studies confirming that ROA wear alters oral microbiological homeostasis due to the presence of new retentive surfaces, the ROA design, and the duration of ROA use, all of which favour bacterial adhesion and biofilm formation.26,29,30 Mahmoudabi et al.17 also reported a significant increase in the prevalence of oral colonisation by Candida spp. at a long-term period in ROA patients, compared to untreated controls. Alternative results were reported by Gonçalves et al.18 who suggested that, although orthodontic treatment may favour the adherence of Candida to epithelial cells, ROA did not influence the presence of yeasts in saliva.

Several studies8,15,21,22 reported a significant increase in candida colonies during the early stages of FOA treatment, compared to pre-treatment levels. However, contrasting results were reported by earlier studies16,23,24 in which FOA did not increase the number of Candida carriers during the first few months, while Kouvelis et al.27 failed to identify Candida albicans during FOA therapy. Hägg et al.14 reported a considerable individual variation in candida counts during the short and the mid-time periods after FOA insertion. A significant increase in candida density on the dorsum of the tongue was found when an imprint culture was used, although the overall prevalence rates of candida obtained using oral saliva and pooled plaque techniques did not demonstrate a change. In contrast, Lee et al.16 found a significant increase in Candida counts in oral saliva after 5 months of FOA. In a mid-term follow-up, a statistical increase in Candida counts was found in patients with FOA in gargled samples21 and dental plaque,22,25 although Grzegocka et al.23 reported a non-significant upward trend. Limited studies reported the long-term effect of FOA on Candida density in contrast with two studies which reported a significant increase15,16 and two other studies reporting non-significant changes.15,16,21,24 Only one study by Soler et al.24 investigated the candida effects after FOA removal, finding that FOA (both metal and ceramic appliances) did not influence the presence of Candida albicans. Khanpayeh et al.19 compared the salivary sample of 80 orthodontic subjects, treated with ROA and FOA by dividing subjects into two groups matched by gender and age. A higher frequency of Candida colonisation was found in the FOA group, compared to the ROA group.

Candida species and orthodontic treatment: summary of evidence

It is accepted that the most common aetiological contributor of oral candidiasis is Candida albicans, which causes 45–75% of the total incidence of candidiasis, whereas C. tropicalis, C. glabrata, C. parapsilosis, C. krusei account for about 7% of all cases.21

The assessment of candida colonies in orthodontic patients compared to untreated controls showed that Candida albicans was the most prevalent species isolated in both groups, although the method of sampling and analysis differed.17,18,25

The analysis of the Candida species showed that the most prevalent species in orthodontic patients was C. albicans, while other yeast species were less common during ROA26 and FOA14,15,16,21,23,24 treatment. Varying levels of Candida strains were reported among the analysed studies, likely due to individual variability and to the different collection methods.

Furthermore, differences in the oral yeasts of patients with or without orthodontic appliances have demonstrated a higher Candida diversity in the orthodontic group. The wearing of orthodontic appliances significantly increased the tendency for colonisation by multiple yeast species, especially non-albicans species (as C. parapsilosis, C. famata, C. sake, C. glabrata).14,15,16,17,18,19,21,23,24,25,26

A higher colonisation of non-albicans Candida species was also seen in FOA subjects compared with ROA subjects (P = 0.001).19 The most frequent species in the ROA group was C. albicans (62.5%), while in the FOA group, the frequency of C. albicans was lower (45%) and the frequencies of other species (C. tropicalis, C. parapsilosis, C. Krusei, C. Kefyr) was higher than in the ROA group. Therefore, FOA seemed to promote an increase in the presence of salivary Candida, particularly non-albicans Candida species compared to ROA patients.19 All of these yeast species have a great ability to form biofilms23,28 in patients undergoing orthodontic therapy,6 mainly in FOA cases.19,28 Candida strains aggregate or adhere more easily to orthodontic fixed appliances.16

The increase in Candida species other than C. albicans in FOA patients, may be due to the different environmental conditions of non-albicans Candida strains. After FOA placement, the pH of plaque, the strains and number of micro-organisms in the oral cavity are altered,8,14,22,23,27 which allows non-albicans strains to proliferate and adhere more easily to FOA.16 Moreover, the increased risk of Candida colonisation in orthodontic patients could be attributed to a varying degree of gingival inflammation and mucosal damage that is often seen during orthodontic therapy, and which could have decreased the local defense mechanisms.20,21 Recent literature28 reported that other local factors, such as mucosal barriers, contributed to the formation of Candida colonies. The first line of defense against the Candida species is an intact mucosa,28 and therefore, there will be an increased risk of infection if there are oral lesions due to local trauma associated with orthodontic appliances.3,24 It is important to consider that the presence of oral appliances does not appear to increase the clinical signs of candida in individuals who are healthy carriers.31 However, Goncalves et al.18 and Zheng et al.21, respectively, reported that the presence of microtrauma of the oral mucosa in orthodontic patients, did not produce candidiasis in the studied patients, despite Candida colonisation.

This situation may be explained by the opportunistic pathogenic character of these micro-organisms, that may cause infection in cases of immuno-suppression. Therefore, clinicians should be cautious when providing orthodontic treatment in immuno-compromised children because of an increased risk of candida infection. This is especially valid during FOA treatment because traumatic mucositis often occurs to the oral mucosa due to FOA irritation throughout treatment.15

Additional host-dependent variables, such as sialometric variations,8,13 immuno-deficiency, a diet rich in sugar and deficient oral hygiene,14,23 should also be considered as contributors to the formation of a Candida spp. biofilm.28

The oral prevention, correct hygiene habits and a greater awareness of children under orthodontic treatment and their parents, not only guarantees the success of treatment, but can also decrease the risk of systemic and/or local diseases, especially in immuno-compromised patients.14,19,21,22,23,24,26

Limitations

Considering the clinical heterogeneity of the reviewed studies, as well as the differences between the sample sites, the analytical methods and, in the quantitative assessment (the number composition was expressed as counts of CFU or as a percentage of frequency), the present review reflects only the changing trend in the colonisation of oral Candida during orthodontic treatment. Further high-quality randomised clinical trials are needed to increase the quality of evidence regarding the changes in the candida population during orthodontic treatment.

Conclusions

According to the SBU tool, the present review may draw conclusions reflecting a limited level of evidence.

ROA induced a temporary increase of Candida counts from an early stage of treatment, back to a pre-treatment level after ROA removal.

Contrasting and conflicting results have been reported for FOA treatment.

FOA therapy seemed to increase the frequency of Candida carriers, compared to ROA.

Orthodontic treatment (especially with FOA) promoted oral Candida colonisation of non-albicans species, although the most prevalent species was Candida albicans in both groups.

Figure 1.

Flow diagram of the included studies according to the PRISMA.
Flow diagram of the included studies according to the PRISMA.

Characteristics of the studies.

No. Study ID/ Design Patients (M/F) Agea Appliance Sample site Timing Analysis method Outcome Additional measures Quality of the study
1 Arendorf 198513 Prospective Exp: 33 (15/18) 8–17 y ROA Six mucosal site (ant and post palate, ant and post tongue, r and l cheek) T0 = before AppInsT1 = during therapyT2 = after AppRem (after average 9 mos) Imprint Culture (Arendorf and Walker technique) Prevalence (%) Density PI + saliv pH C
2 Hägg 200414 Prospective Exp: 27 (13/14) 15.5 + 2.3 y FOA Rinse Dorsum of the tongue Supra and subgingival plaque T0=before AppInsT1 = 1 mos after T0T2 = 2 mos after T0T3 = 3 mos after T0 Oral Rinse (Samaranayake technique) Imprint Culture (Arendorf and Walker technique) (SDA, Gram stain, germ tube test, API 20 C AUX) Pooled Plaque Prevalence (%)Density (CFU)Species composition PI + count of Enterobacteriaceae + total bacterial count B
3 Arslan 200815 Prospective Exp 1: 72Exp 2: 42 (19/23) Candida carriers out of 72 subjects, that were treated 19.8 y FOA (metal brackets) Dorsum of the tongue (only for T0)Mid-palate (only for T0)SalivaU5/L5U1/L1 T0 = before AppInsT1 = 1 mos after T0T2 = 6 mos after T0T3 = 12 mos after T0 Swab Culture (Kleinegger method, SDA)Salivary culture (SDA, Gram staining, germ-tube test, chlamydospore, API 20C AUX system))Pooled plaque (SDA) Prevalence (%)Density (CFU)Species composition None B
4 Lee 200816 Prospective Exp: 97 (38/59) 17.7 y FOA Rinse From T0 = before AppIns to T10 = 12 mos after T0 Oral rinse technique (Samaranayake technique, SDA)Phenotypic methods (germ-tube test; API ID 32C)Genotypic methods (RAPD analysis)Dendogram analysis Prevalence (%)Species composition None C
5 Mahmoudadabi 200917 Prospective Exp 1: 34Exp 2: 34 13 y (Exp 1)12.5 y (Exp 2) ROA (upper) Cr Saliva Surface of upper appliance (not considered) T0 = before AppInsT1 = over 8 mos after T0 Culture (Arendorf and Walker, Davenport techiques) (CHROMagar; germ-tube test) Prevalence (%)Count (CFU)Species composition None C
6 Gonçalves e Silva 201418 Prospective Exp 1: 30Exp 2: 30 9.1+−1.7 (Exp 1)7.7+−1.5 (Exp 2) ROA Cr Cheek and lateral surface of the tongue Saliva T0 = before AppInsT1 = at least 6 mos after T0 Culture (SDA; CHROMagar) Phenotypic methods Exfoliative cytology Prevalence (%)Count (CFU)Species composition Counts of Anti-C.albicansIgA B
7 Arab 20168 Prospective Exp 1: 30 (6/24) 12–18 y FOA Saliva T0 = before AppInsT1 = 6 we after T0T2 = 12 we after T0T3 = 18 we after T0 Culture (SDA) Count (CFU) Salivary flow and pH Microbial counts (S. mutans/L. acidophilus) C
8 Khanpayeh 201419 Prospective Exp 1: 40Exp 2: 40 (35/45) 7–18 y FOA (metal) ROA Unstimulated saliva T0 = before AppInsT1 = 6 mos after T0 Culture (SDA; Germ-tube test; corn meal agar)Biochemical tests (API 20C method) Frequency (%)Species composition None B
9 Kundu 201620 Prospective Exp 1: 10Exp 2: 10 (not considered) 6–15 y ROA Fixed space maintainers (nc) Unstimulated saliva T0 = before AppInsT1 = 1 mo after T0T2 = 3 mos after T0T3 = 6 mos after T0 Culture (SDA) Count (CFU) Bacterial count (S. mutans and Lactobacillussp.) B
10 Zheng 201621 Prospective Exp 1: 50 (23/27) 10–18 (13.6 y) FOA Gargle T0 = before AppInsT1 = 1 mo after T0T2 = 2 mos after T0T3 = 3 mos after T0T4 = 6 mos after T0 Culture (CHROMagar)PCR (Tiangen Biotech) Incidence (%)Count (CFU)Species composition None B
11 Shukla 201722 Prospective Exp 1: 60 16–18 y FOA Buccal and labial Plaque of anterior teeth and U6 + L6 T0 = before AppInsT1 = 2 mo after T0T2 = 3 mos after T0 Swab Culture (SDA; Gram stain; germ tube test, counts in CFU) Count (CFU) S. mutans B
12 Grzegocka 202023 Prospective Exp 1: 17 (6M/11) 17+−7 y FOA Oral rinse Elastomeric rings (nc) T0 = before AppInsT1 = 2 we after T0T2 = 6 we after T0T3 = 12 we after T0 Culture (Dalmau plate technique)Biochemical tests (API 20C AUX) Prevalence (%)Count(CFU) Species composition APIGBIBiofilm formation C
13 Sanz-Orrio-Soler 202024 Prospective Controlled Trial Exp 1: 124 (43/80) 19.5 y FOA (metal or ceramic) U and L vestibule T0 = before AppInsT1 = 1 mo after T0T2 = 6 mos after T0T3 = 12 mos after T0T4 = 6 mos after Swab Culture (CHROMagar plates, Becton Dickinson) Frequency (%)Species composition Questionnaire about hygiene habits B
14 Pellissari 202125 Prospective Exp 1: 23 (7/10)Exp 2: 6 (2/4) 20.7+− 8.7 y (Exp 1)19.6+−1.3 y (Exp 2) FOACr Biofilm around bck From 3 to 6 mos after AppIns Culture Biochemical tests (VITEK 2 compact system) Prevalence (%)Species composition Fungal strains and resistance to Antifungals Bacterial strains and resistance to Antimicrobials B
15 Rodríguez Rentería 202126 Prospective Exp 1: 55 (34/21) 8.4 y ROA Support oral mucosa Surface of ROA (not considered) T0 = before AppInsT1 = 4 we after T0 Chromogenic culture (ID 32 C AUX system) Frequency (%)Species composition Microbial species (Str.aureus, P.aeruginosa) C
16 Kouvelis 202127 Prospective Exp 1: 30 (17/13) 13.97 +− 2.07 FOA Saliva T0 = before AppInsT1 = 4 we after T0T1 = 12 we after T0 Culture Count Salivary pH, flow rate, buffering capacityOther microbial species C

List of inclusion and exclusion criteria.

Field Inclusion Exclusion
Patients Children, adolescents or young adults (<25 years) of any sex, ethnicity and malocclusion, in general good health Adults (>25 years)In vitro studiesAnimal studies
Intervention (exposure) Orthodontic treatment with any vestibular fixed appliance (metal or ceramic, conventionally-ligated or self-ligated) or any removable appliances Patients not receiving orthodontic treatmentPatients receiving orthodontic treatment without specific descriptions of the materials and applied techniquePatients receiving partial appliancesPatients receiving or having received systemic antibiotic treatment less than a month before or during orthodontic treatmentSmoking patients
Comparison A. No comparison (For the descriptive analysis of Candida changes in treated patients)B. Ortho-tx vs no-tx (Comparison between treated and non treated patients)C. Ortho-tx vs ortho-tx (Comparison between ROA and FOA)
Outcome Quantitative and qualitative analysis of Candida colonies, from intra-oral mucosal sites, saliva or supra/sub-gingival plaque.All available time-points will be included and categorized into pre-treatment, short-term (< 3 months) treatment, mid-term (3–6 months) treatment and long-term (< 6 months) treatment, post-treatment No clear mention of the analysis or time-point
Study design Randomized clinical trials or non-randomized, prospective or retrospective, cohort studies

Swedish council on technology assessment in health-care (SBU) criteria for grading assessed studies.

SBU criteria for grading assessed studies
Grade A (High level of evidence)Randomized clinical study or prospective study with a well-defined control group, defined diagnosis and endpoints, diagnostic reliability tests and reproducibility tests described
Grade B (Moderate level of evidence)Cohort study or retrospective case series with defined control or reference group, defined diagnosis and endpoints, diagnostic reliability tests and reproducibility tests described
Grade C (Low level of evidence)Large attrition, unclear diagnosis and endpoints, poorly defined patient material

Definitions of evidence level.

Level Evidence Definition
1 Strong At least two studies assessed with level “A”
2 Moderate One study with level “A” and at least two studies with level “B”
3 Limited At least two studies with level “B”
4 Inconclusive Fewer than two studies with level “B”

Dar-Odeh N, Shehabi A, Al-bitar Z, Al-Omari I, Badran S, Al-Omiri M, et al. Oral Candida colonization in patients with fixed orthodontic appliances: the importance of some nutritional and salivary factors. Afric J Microbio Res 2011;5:2150–4. Dar-OdehN ShehabiA Al-bitarZ Al-OmariI BadranS Al-OmiriM Oral Candida colonization in patients with fixed orthodontic appliances: the importance of some nutritional and salivary factors Afric J Microbio Res 2011 5 2150 4 Search in Google Scholar

Akpan A, Morgan R. Oral candidiasis. Postgrad Med J 2002;78:455–9. AkpanA MorganR Oral candidiasis Postgrad Med J 2002 78 455 9 10.1136/pmj.78.922.455174246712185216 Search in Google Scholar

Hibino K, Wong RW, Hägg U, Samaranayake LP. The effects of orthodontic appliances on Candida in the human mouth. Int J Paediatr Dent 2009;19:301–8. HibinoK WongRW HäggU SamaranayakeLP The effects of orthodontic appliances on Candida in the human mouth Int J Paediatr Dent 2009 19 301 8 10.1111/j.1365-263X.2009.00988.x19486368 Search in Google Scholar

Reedijk AMJ, Kremer LC, Visser O, Lemmens V, Pieters R, Coebergh JWW, et al. Increasing incidence of cancer and stage migration towards advanced disease in children and young adolescents in the Netherlands, 1990–2017. Eur J Cancer 2020;134:115–26. ReedijkAMJ KremerLC VisserO LemmensV PietersR CoeberghJWW Increasing incidence of cancer and stage migration towards advanced disease in children and young adolescents in the Netherlands, 1990–2017 Eur J Cancer 2020 134 115 26 10.1016/j.ejca.2020.04.01132521425 Search in Google Scholar

Mitus-Kenig M, Derwich M, Czochrowska E, Pawlowska E. Cancer survivors present significantly lower long-term stability of orthodontic treatment: a prospective case-control study. Eur J Orthod 2021;43:631–8. Mitus-KenigM DerwichM CzochrowskaE PawlowskaE Cancer survivors present significantly lower long-term stability of orthodontic treatment: a prospective case-control study Eur J Orthod 2021 43 631 8 10.1093/ejo/cjaa083864340033432985 Search in Google Scholar

Lucchese A, Bondemark L, Marcolina M, Manuelli M. Changes in oral microbiota due to orthodontic appliances: a systematic review. J Oral Microbiol 2018;10:1476645. LuccheseA BondemarkL MarcolinaM ManuelliM Changes in oral microbiota due to orthodontic appliances: a systematic review J Oral Microbiol 2018 10 1476645 10.1080/20002297.2018.1476645603202029988826 Search in Google Scholar

Jiang Q, Li J, Mei L, Du J, Levrini L, Abbate GM, et al. Periodontal health during orthodontic treatment with clear aligners and fixed appliances: a meta-analysis. J Am Dent Assoc 2018;149:712–20; e12. JiangQ LiJ MeiL DuJ LevriniL AbbateGM Periodontal health during orthodontic treatment with clear aligners and fixed appliances: a meta-analysis J Am Dent Assoc 2018 149 712 20 e12 10.1016/j.adaj.2018.04.01029921415 Search in Google Scholar

Arab S, Nouhzadeh Malekshah S, Abouei Mehrizi E, Ebrahimi Khanghah A, Naseh R, Imani MM. Effect of Fixed Orthodontic Treatment on Salivary Flow, pH and Microbial Count. J Dent (Tehran) 2016;13:18–22. ArabS Nouhzadeh MalekshahS Abouei MehriziE Ebrahimi KhanghahA NasehR ImaniMM Effect of Fixed Orthodontic Treatment on Salivary Flow, pH and Microbial Count J Dent (Tehran) 2016 13 18 22 Search in Google Scholar

Ghazal ARA, Idris G, Hajeer MY, Alawer K, Cannon RD. Efficacy of removing Candida albicans from orthodontic acrylic bases: an in vitro study. BMC Oral Health 2019;19:71. GhazalARA IdrisG HajeerMY AlawerK CannonRD Efficacy of removing Candida albicans from orthodontic acrylic bases: an in vitro study BMC Oral Health 2019 19 71 10.1186/s12903-019-0765-x649859031046747 Search in Google Scholar

Belibasakis GN, Bostanci N, Marsh PD, Zaura E. Applications of the oral microbiome in personalized dentistry. Arch Oral Biol 2019;104:7–12. BelibasakisGN BostanciN MarshPD ZauraE Applications of the oral microbiome in personalized dentistry Arch Oral Biol 2019 104 7 12 10.1016/j.archoralbio.2019.05.02331153099 Search in Google Scholar

Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gotzsche PC, Ioannidis JP, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. J Clin Epidemiol 2009;62:e1–e34. LiberatiA AltmanDG TetzlaffJ MulrowC GotzschePC IoannidisJP The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration J Clin Epidemiol 2009 62 e1 e34 10.1016/j.jclinepi.2009.06.00619631507 Search in Google Scholar

Bondemark L, Holm AK, Hansen K, Axelsson S, Mohlin B, Brattstrom V, et al. Long-term stability of orthodontic treatment and patient satisfaction. A systematic review. Angle Orthod 2007;77:181–91. BondemarkL HolmAK HansenK AxelssonS MohlinB BrattstromV Long-term stability of orthodontic treatment and patient satisfaction. A systematic review Angle Orthod 2007 77 181 91 10.2319/011006-16R.117029533 Search in Google Scholar

Arendorf T, Addy M. Candidal carriage and plaque distribution before, during and after removable orthodontic appliance therapy. J Clin Periodontol 1985;12:360–8. ArendorfT AddyM Candidal carriage and plaque distribution before, during and after removable orthodontic appliance therapy J Clin Periodontol 1985 12 360 8 10.1111/j.1600-051X.1985.tb00926.x3859496 Search in Google Scholar

Mahmoudabadi AZ, Drucker DB, Mandall N, O’Brien K, Johnson EM, Theaker ED. The oral yeast flora: Effect of upper removable orthodontic appliances. Microbial Ecol Health Dis 2002;14:149–52. MahmoudabadiAZ DruckerDB MandallN O’BrienK JohnsonEM TheakerED The oral yeast flora: Effect of upper removable orthodontic appliances Microbial Ecol Health Dis 2002 14 149 52 10.1080/089106002320644320 Search in Google Scholar

Kundu R, Tripathi AM, Jaiswal JN, Ghoshal U, Palit M, Khanduja S. Effect of fixed space maintainers and removable appliances on oral microflora in children: an in vivo study. J Indian Soc Pedodontics Preventive Dentistry 2016;34:3–9. KunduR TripathiAM JaiswalJN GhoshalU PalitM KhandujaS Effect of fixed space maintainers and removable appliances on oral microflora in children: an in vivo study J Indian Soc Pedodontics Preventive Dentistry 2016 34 3 9 10.4103/0970-4388.17549826838141 Search in Google Scholar

Rodríguez-Rentería M, Márquez-Preciado R, Ortiz-Magdaleno M, Bermeo-Escalona J, Sánchez-Vargas LO. Frequency of pathogenic microorganisms in removable orthodontic appliances and oral mucosa in children. J Clin Pediatric Dentistry 2021;45:135–9. Rodríguez-RenteríaM Márquez-PreciadoR Ortiz-MagdalenoM Bermeo-EscalonaJ Sánchez-VargasLO Frequency of pathogenic microorganisms in removable orthodontic appliances and oral mucosa in children J Clin Pediatric Dentistry 2021 45 135 9 10.17796/1053-4625-45.2.1133951170 Search in Google Scholar

Hägg U, Kaveewatcharanont P, Samaranayake YH, Samaranayake LP. The effect of fixed orthodontic appliances on the oral carriage of Candida species and Enterobacteriaceae. Eur J Orthodontics 2004;26:623–9. HäggU KaveewatcharanontP SamaranayakeYH SamaranayakeLP The effect of fixed orthodontic appliances on the oral carriage of Candida species and Enterobacteriaceae Eur J Orthodontics 2004 26 623 9 10.1093/ejo/26.6.62315650072 Search in Google Scholar

Arslan SG, Akpolat N, Kama JD, Ozer T, Hamamci O. One-year follow-up of the effect of fixed orthodontic treatment on colonization by oral Candida. J Oral Pathol Med 2008;37:26–9. ArslanSG AkpolatN KamaJD OzerT HamamciO One-year follow-up of the effect of fixed orthodontic treatment on colonization by oral Candida J Oral Pathol Med 2008 37 26 9 10.1111/j.1600-0714.2007.00574.x18154574 Search in Google Scholar

Lee W, Low BK, Samaranayake LP, Hagg U. Genotypic variation of Candida albicans during orthodontic therapy. Front Biosci 2008;13:3814–24. LeeW LowBK SamaranayakeLP HaggU Genotypic variation of Candida albicans during orthodontic therapy Front Biosci 2008 13 3814 24 10.2741/297018508476 Search in Google Scholar

Zheng Y, Li Z, He X. Influence of fixed orthodontic appliances on the change in oral Candida strains among adolescents. J Dental Sci 2016;11:17–22. ZhengY LiZ HeX Influence of fixed orthodontic appliances on the change in oral Candida strains among adolescents J Dental Sci 2016 11 17 22 10.1016/j.jds.2014.02.001639515530894940 Search in Google Scholar

Shukla C, Maurya R, Singh V, Tijare M. Evaluation of role of fixed orthodontics in changing oral ecological flora of opportunistic microbes in children and adolescent. J Indian Soc Pedodontics Preventive Dentistry 2017;35:34–40. ShuklaC MauryaR SinghV TijareM Evaluation of role of fixed orthodontics in changing oral ecological flora of opportunistic microbes in children and adolescent J Indian Soc Pedodontics Preventive Dentistry 2017 35 34 40 10.4103/0970-4388.19922628139480 Search in Google Scholar

Grzegocka K, Krzyściak P, Hille-Padalis A, Loster JE, Talaga-Ćwiertnia K, Loster BW. Candida prevalence and oral hygiene due to orthodontic therapy with conventional brackets. BMC Oral Health 2020;20:277. GrzegockaK KrzyściakP Hille-PadalisA LosterJE Talaga-ĆwiertniaK LosterBW Candida prevalence and oral hygiene due to orthodontic therapy with conventional brackets BMC Oral Health 2020 20 277 10.1186/s12903-020-01267-4754752633036600 Search in Google Scholar

Sanz-Orrio-Soler I, Arias de Luxán S, Sheth CC. Oral colonization by Candida species in orthodontic patients before, during and after treatment with fixed appliances: a prospective controlled trial. J Clin Exp Dent 2020;12:e1071–e7. Sanz-Orrio-SolerI Arias de LuxánS ShethCC Oral colonization by Candida species in orthodontic patients before, during and after treatment with fixed appliances: a prospective controlled trial J Clin Exp Dent 2020 12 e1071 e7 10.4317/jced.57565768056333262874 Search in Google Scholar

Kouvelis G, Papadimitriou A, Merakou K, Doulis I, Karapsias S, Kloukos D. A prospective cohort study assessing the impact of fixed orthodontic appliances on saliva properties and oral microbial flora. Oral Health Preventive Dentistry 2021;19:67–76. KouvelisG PapadimitriouA MerakouK DoulisI KarapsiasS KloukosD A prospective cohort study assessing the impact of fixed orthodontic appliances on saliva properties and oral microbial flora Oral Health Preventive Dentistry 2021 19 67 76 Search in Google Scholar

Gonçalves e Silva CR, Oliveira LD, Leão MV, Jorge AO. Candida spp. adherence to oral epithelial cells and levels of IgA in children with orthodontic appliances. Braz Oral Res 2014;28:28–32. Gonçalves e SilvaCR OliveiraLD LeãoMV JorgeAO Candida spp. adherence to oral epithelial cells and levels of IgA in children with orthodontic appliances Braz Oral Res 2014 28 28 32 10.1590/S1806-8324201300500003125000599 Search in Google Scholar

Pellissari BA, Sabino GSP, de Souza Lima RN, Motta RHL, Suzuki SS, Garcez AS, et al. Antimicrobial resistance of bacterial strains in patients undergoing orthodontic treatment with and without fixed appliances. Angle Orthod 2021;91:672–79. PellissariBA SabinoGSP de Souza LimaRN MottaRHL SuzukiSS GarcezAS Antimicrobial resistance of bacterial strains in patients undergoing orthodontic treatment with and without fixed appliances Angle Orthod 2021 91 672 79 10.2319/120720-990.1837615533901282 Search in Google Scholar

Khanpayeh E, Jafari AA, Tabatabaei Z. Comparison of salivary Candida profile in patients with fixed and removable orthodontic appliances therapy. Iranian J Microbiol 2014;6:263–8. KhanpayehE JafariAA TabatabaeiZ Comparison of salivary Candida profile in patients with fixed and removable orthodontic appliances therapy Iranian J Microbiol 2014 6 263 8 Search in Google Scholar

Khan I, Ahmad T, Manzoor N, Rizvi MA, Raza U, Premchandani S. Evaluating the role of local host factors in the candidal colonization of oral cavity: a review update. Natl J Maxillofac Surg 2020;11:169–75. KhanI AhmadT ManzoorN RizviMA RazaU PremchandaniS Evaluating the role of local host factors in the candidal colonization of oral cavity: a review update Natl J Maxillofac Surg 2020 11 169 75 10.4103/njms.NJMS_161_20805166833897176 Search in Google Scholar

Freitas AO, Marquezan M, Nojima Mda C, Alviano DS, Maia LC. The influence of orthodontic fixed appliances on the oral microbiota: a systematic review. Dental Press J Orthod 2014;19:46–55. FreitasAO MarquezanM Nojima MdaC AlvianoDS MaiaLC The influence of orthodontic fixed appliances on the oral microbiota: a systematic review Dental Press J Orthod 2014 19 46 55 10.1590/2176-9451.19.2.046-055.oar429660924945514 Search in Google Scholar

Guo R, Lin Y, Zheng Y, Li W. The microbial changes in subgingival plaques of orthodontic patients: a systematic review and meta-analysis of clinical trials. BMC Oral Health 2017;17:90. GuoR LinY ZhengY LiW The microbial changes in subgingival plaques of orthodontic patients: a systematic review and meta-analysis of clinical trials BMC Oral Health 2017 17 90 10.1186/s12903-017-0378-1545517428576147 Search in Google Scholar

Ronsani MM, Mores Rymovicz AU, Meira TM, Trindade Grégio AM, Guariza Filho O, Tanaka OM, et al. Virulence modulation of Candida albicans biofilms by metal ions commonly released from orthodontic devices. Microb Pathog 2011;51:421–5. RonsaniMM Mores RymoviczAU MeiraTM Trindade GrégioAM Guariza FilhoO TanakaOM Virulence modulation of Candida albicans biofilms by metal ions commonly released from orthodontic devices Microb Pathog 2011 51 421 5 10.1016/j.micpath.2011.08.00721925586 Search in Google Scholar

Recommended articles from Trend MD

Plan your remote conference with Sciendo