Marcela Cristina Damião Andrucioli

Comparison of two cleansing pastes for the removal of biofilm from dentures and palatal lesions in patients with atrophic chronic candidiasis

The efficacy of 2 oral hygiene products, an experimental toothpaste specific for complete denture cleansing and a regular standard toothpaste, was compared in terms of denture biofilm removal and cure of palatal lesions in patients with atrophic chronic candidiasis. The degree of correlation between presence of biofilm and mucosa erythema was also evaluated. Twenty-four complete denture wearers (45-80 years old) were divided into 2 groups: experimental paste and standard toothpaste (Sorriso-Kolynos, Brazil). Both groups received soft toothbrushes. The internal surfaces of upper dentures were stained using 1% sodium fluorescein and photographed at a 45 masculine angle at 0, 15, 30 and 60 days. The slides were scanned and the areas of interest (denture total area and biofilm area) were measured (Image Tool software). The degree of erythema was evaluated on slides according to the Prosthesis Tissue Index. There was a significant reduction (1%) in the degree of biofilm (ANOVA/Tukey) between the two initial visits (0 and 15 days) and the two final visits (30 and 60 days), and in the average erythema scores (Kruskal-Wallis) between 0 and 60 days, in both groups. The Mann-Whitney test showed a significant difference (1%) between pastes in terms of biofilm degree, but no difference was found for the erythema score. Correlation values between biofilm and erythema degree were 0.3801 (experimental paste) and (0.3678 (standard toothpaste). We may therefore conclude that the experimental product was efficient for the removal of denture plaque biofilm.

Gram-negative periodontal pathogens and bacterial endotoxin in metallic orthodontic brackets with or without an antimicrobial agent: An in-vivo study

INTRODUCTION High levels of periodontal pathogens can cause periodontal alterations. The presence of endotoxin might be responsible for the occurrence and progression of tissue inflammation and bone resorption. The aims of this study were to use checkerboard DNA-DNA hybridization and limulus amebocyte lysate assay to evaluate in metallic orthodontic brackets (1) the presence of 16 gram-negative periodontal pathogenic microorganisms of the orange complex and red complex +Treponema socranskii, (2) the amount of bacterial endotoxin, and (3) the efficacy of 0.12% chlorhexidine gluconate mouthwash in reducing bacterial contamination and endotoxin amount. METHODS Thirty-three patients (ages, 11-33 years) under orthodontic treatment with fixed appliances had 3 new metallic brackets bonded to 3 different premolars. Sixteen patients used a 0.12% chlorhexidine gluconate mouthwash (Periogard, Colgate-Palmolive, São Bernardo do Campo, São Paulo, Brazil) (experimental group), and 17 patients used a placebo mouthwash (control group) twice a week. After 30 days, the brackets were removed, and the samples were obtained. The data were analyzed statistically by Mann-Whitney, Kruskal-Wallis, and Dunn tests (α = 0.05). RESULTS The 0.12% chlorhexidine gluconate group accumulated significantly lower levels of microorganisms than did the placebo group (P = 0.01). When each microbial complex was analyzed separately, a statistically significant difference between the experimental and control groups was found for the orange complex (P = 0.04). A greater amount of bacterial endotoxin was detected in the 0.12% chlorhexidine gluconate group than in the control group (P = 0.02). CONCLUSIONS The 0.12% chlorhexidine gluconate oral rinses can be useful to reduce the levels of gram-negative periodontal pathogenic microorganisms in patients with fixed orthodontic appliances. Considering the increased amount of bacterial endotoxin after chlorhexidine gluconate use, further research is necessary to develop clinical procedures or antimicrobial agents with action against bacterial endotoxin adhering to metallic brackets.

Use of the checkerboard DNA–DNA hybridisation technique for in vivo detection of cariogenic microorganisms on metallic brackets, with or without use of an antimicrobial agent

OBJECTIVE Using checkerboard DNA-DNA hybridisation (CDDH) assay, this randomised clinical study evaluated the contamination of metallic brackets by four cariogenic bacterial strains (Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei and Lactobacillus acidophilus) and the efficacy of 0.12% chlorhexidine gluconate (CHX) mouthwashes in reducing bacterial contamination. METHODS Thirty-nine 11-33-year-old patients under treatment with fixed orthodontic appliances were enrolled in the study and had 2 new metallic brackets bonded to premolars. Nineteen patients used a 0.12% CHX mouthwash (Periogard) and 20 patients used a placebo mouthwash (control) twice a week. After 30 days, the brackets were removed and samples were obtained for analysis by CDDH. Data were analysed statistically by the Kruskal-Wallis test (α=0.05) using the SAS software. RESULTS S. mutans, S. sobrinus, L. casei and L. acidophilus were detected in 100% of the samples from both groups. However, brackets of the control group were more heavily contaminated by S. mutans and S. sobrinus (P<0.01). In the experimental group, although all counts decreased after rinsing with the chlorhexidine solution, there was significant difference only for S. mutans (P=0.03). CONCLUSIONS The use of 0.12% chlorhexidine gluconate mouthwashes can be useful in clinical practice to reduce the levels of cariogenic microorganisms in patients under treatment with fixed orthodontic appliances.

Orthodontic-surgical treatment of class III malocclusion with mandibular asymmetry

Class III skeletal malocclusion may present several etiologies, among which maxillary deficiency is the most frequent. Bone discrepancy may have an unfavorable impact on esthetics, which is frequently aggravated by the presence of accentuated facial asymmetries. This type of malocclusion is usually treated with association of Orthodontics and orthognathic surgery for correction of occlusion and facial esthetics. This report presents the treatment of a patient aged 15 years and 1 month with Class III skeletal malocclusion, having narrow maxilla, posterior open bite on the left side, anterior crossbite and unilateral posterior crossbite, accentuated negative dentoalveolar discrepancy in the maxillary arch, and maxillary and mandibular midline shift. Clinical examination also revealed maxillary hypoplasia, increased lower one third of the face, concave bone and facial profiles and facial asymmetry with mandibular deviation to the left side. The treatment was performed in three phases: presurgical orthodontic preparation, orthognathic surgery and orthodontic finishing. In reviewing the patients final records, the major goals set at the beginning of treatment were successfully achieved, providing the patient with adequate masticatory function and pleasant facial esthetics.

Corrosion in Haas expanders with and without use of an antimicrobial agent: an in situ study

Objectives The purpose of this study was to evaluate in situ the occurrence of corrosion in the soldering point areas between the wire, silver brazing and band in Haas expanders. Material and Methods Thirty-four 7-12-year-old patients who needed maxillary expansion with a Haas expander were randomly assigned to two groups of 17 individuals each, according to the oral hygiene protocol adopted during the orthodontic treatment: Group I (control), toothbrushing with a fluoride dentifrice and Group II (experimental), toothbrushing with the same dentifrice plus 0.12% chlorhexidine gluconate (Periogard®) mouthrinses twice a week. The appliances were removed after approximately 4 months. Fragments of the appliances containing a metallic band with a soldered wire were sectioned at random for examination by stereomicroscopy, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS). Data were analyzed statistically by Fishers test at 5% significance level. Results The analysis by optical microscopy revealed areas with color change suggestive of corrosion in the soldering point areas joining the band and the wire in all specimens of both groups, with no statistically significant difference between the groups (p=1). The peaks of chemical elements (Ni, Fe, Cr, O, C and P) revealed by EDS were also similar in both groups. Conclusion: Color changes and peaks of chemical elements suggestive of corrosion were observed in the soldering point areas between the wire, silver brazing and band in both control and experimental groups, which indicate that the 0.12% chlorhexidine gluconate mouthrinses did not influence the occurrence of corrosion in situ.

Bacterial biofilm on successful and failed orthodontic mini-implants—a scanning electron microscopy study

Mini‐implants have been extensively used in Orthodontics as temporary bone anchorage devices. However, early failure of mini‐implants due to mobility might occur and the colonization of their surfaces by pathogenic bacteria has been referred to as one of the contributing factors. In this study, scanning electron microscopy (SEM) was used to assess the presence of microorganisms adhered to the surface of mini‐implants that failed due to loss of stability. Twelve self‐drilling titanium mini‐implants (1.6 mm diameter × 9.0 mm long) were collected from 12 patients undergoing orthodontic treatment—7 successful and 5 failed mini‐implants. The mean time of permanence in the mouth was 15.8 and 2.4 months for successful and failed mini‐implants, respectively. The devices were placed in the maxilla and/or mandible and removed by the same surgeon and were processed for SEM analysis of the presence of microorganisms on their surfaces (head, transmucosal profile, and body). Extensive bacterial colonization on mini‐implant head and transmucosal profile was observed in all successful and failed mini‐implants. None of the failed mini‐implants exhibited bacteria on its body and only one mini‐implant belonging to the successful (stable) group exhibited bacteria on its body. The results did not suggest a relationship between failure and presence of bacterial colonies on mini‐implant surfaces. Microsc. Res. Tech. 78:1112–1116, 2015.

Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin

Abstract Objectives Using two groups of mini-implants (successful and failed) the objectives of this in vivo study were: to evaluate the microbial contamination by the checkerboard DNA-DNA hybridization technique and to quantify the bacterial endotoxin by the limulus amebocyte lysate assay. Material and Methods The 15 successful and 10 failed mini-implants (1.6 mm diameter × 7.0 or 9.0 mm long), placed in the maxilla and/or mandible, were obtained from 15 patients undergoing orthodontic treatment. Data were analyzed statistically by the Wilcoxon rank-sum test using the SAS software (a=0.05). Results All 40 microbial species were detected in both groups of mini-implants, with different frequencies. No differences were observed between the groups with respect to microbial complexes (blue, purple, yellow, green, orange, red and other species) and endotoxin quantification (p>0.05). Conclusion Neither microbial contamination nor endotoxin quantification was determinant for the early loss of stability of the mini-implants.

Cytokine profile changes in gingival crevicular fluid after placement different brackets types

OBJECTIVE The aim of this study was to examine the relationship between bracket design and ratio of five proinflammatory cytokine, in gingival crevicular fluid (GCF), and bacterial adhesion without tooth movement influence. DESIGN The sample was comprised of 20 participants, aged 11 to 15 years old (mean age: 13.3 years±1.03). A conventional Gemini™ metallic bracket and two self-ligating brackets, In-Ovation®R and SmartClip™, were bonded to the maxillary incisors and canines. GCF was collected using a standard filter paper strip before and 60days after bonding. The cytokine levels (IL-12, IL-1α, IL-1β, IL-6 and TNF-α) were performed by the LUMINEX assay. The levels of the red and orange bacterial complexes were analyzed by the Checkerboard DNA-DNA hybridization. The data of cytokine and bacterial complexes were carried out using the non-parametric tests at 5% of significance level. RESULTS Increased cytokine levels were observed. However, only the SmartClip™ group showed a significantly increased level of TNF-α (p=0.046). The SmartClip™ brackets group presented higher levels of red complex bacteria. CONCLUSIONS The bracket design affected cytokine levels and bacterial adhesion since it was observed that the proinflammatory cytokines released in GCF to the SmartClip™ group showed an increase in the TNF-α levels associated with higher bacterial levels, which possibly represents greater inflammatory potential. Thereby, the bracket design should be considered in patients with risk of periodontal disease and root resorption.

Influence of resin-modified glass ionomer and topical fluoride on levels of Streptococcus mutans in saliva and biofilm adjacent to metallic brackets

Abstract Decalcification of enamel during fixed orthodontic appliance treatment remains a problem. White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. The use of fluoride-containing orthodontic materials has shown inconclusive results on their ability to reduce decalcification. The aims of this investigation were to compare the levels of Streptococcus mutans (SM) in saliva and biofilm adjacent to orthodontic brackets retained with a resin-modified glass ionomer cement (RMGIC) (Fuji ORTHO LC) and a light cured composite resin (Transbond XT), and to analyze the influence of topical application of the 1.23% acidulated phosphate fluoride (APF) on SM counts. In a parallel study design, two groups (n=14/15) were used with random allocation and high salivary SM counts before treatment. Biofilm was collected from areas adjacent to the brackets on teeth 13, 22, 33, and 41. Both saliva and biofilm were collected on the 7th, 21st, 35th, and 49th days after appliance placement. Topical fluoride application was carried out on the 35th day. Bonding with RMGIC did not alter SM counts in saliva or biofilm adjacent to the brackets. On the other hand, the biofilm adjacent to brackets retained with composite resin showed a significant increase in SM counts along the trial period. Topical application of 1.23% APF did not reduce salivary or biofilm SM counts regardless of the bonding material. In conclusion, fluoride topical application did not show efficacy in reducing SM. The use of RMGIC as bonding materials allowed a better control of SM cfu counts in dental biofilm hindering the significant increase of these microorganisms along the trial period, which was observed in the biofilm adjacent to the composite material.