Rogério Gleiser

Orthodontic treatment need in a group of 9-12-year-old Brazilian schoolchildren

The present study aimed to evaluate the need for orthodontic treatment in Brazilian schoolchildren presenting both late mixed dentition and early permanent dentition as well as to determine the possible factors associated with this necessity. Our randomly selected sample consisted of 407 schoolchildren aged between 9 and 12 years from Nova Friburgo (State of Rio de Janeiro), Brazil. All the children were evaluated according to the two components of the Index of Orthodontic Treatment Need (IOTN), namely, the Dental Health Component (DHC) and the Aesthetic Component (AC). Data analysis involved multiple logistic regression. Definite need for orthodontic treatment was found in 34.2% and 11.3% of the children according to, respectively, DHC and AC. The most prevalent malocclusions included the following: contact point displacement (crowding), crossbite, and increased overjet. Male gender, permanent dentition and aesthetic reasons were factors associated with a great need for orthodontic treatment. It was concluded that about one-third of the children evaluated had a definite need for orthodontic treatment. This necessity was greater in the permanent dentition, thus emphasizing the importance of an early identification of malocclusions and a timely referral of patients for treatment. The correlation between AC and DHC was considered important since they involve distinctive characteristics.

Prevalência de más oclusões em crianças de 9 a 12 anos de idade da cidade de Nova Friburgo (Rio de Janeiro)

INTRODUCTION: Knowledge of a populations epidemiological situation is important in the planning and provision of dental services. OBJECTIVES: Assess the prevalence of malocclusion in children aged 9 to 12 years old from public schools in the city of Nova Friburgo, Rio de Janeiro State, Brazil. METHODS: A randomly selected sample consisting of 407 children (53.1% female) who were evaluated by a trained professional, after parental consent. RESULTS: The most prevalent malocclusions were crowding (45.5%), excessive overjet (29.7%), posterior crossbite (19.2%), anterior diastema (16.2%), partially erupted teeth (12.0%) and excessive overbite (10.8%). Class I molar relationship prevailed (76.7%). The presence of diastemas was higher in females and excessive overbite was more prevalent in males, both in mixed dentition. Negative overjet and the presence of partially erupted teeth had a higher prevalence in permanent dentition. CONCLUSION: It was observed that the mere evaluation of malocclusion prevalence does not reveal case severity or treatment need, both of which are important factors in public health planning.

Inhibitory activity of root canal irrigants against Candida albicans, Enterococcus faecalis and Staphylococcus aureus

The present study evaluated the antimicrobial activity of three root canal irrigants against Enterococcus faecalis, Candida albicans, and Staphylococcus aureus. These microorganisms were incubated in the presence of citric acid (6 and 10%), EDTA (17%), and NaOCl (0.5, 1.0, 2.5, and 5.25%). Agar diffusion tests were performed and redox indicator resazurin was used to evaluate the inhibitory effect of the irrigants on the metabolic activity of these microorganisms. The mean diameters of the inhibition zones for the C. albicans cultures were 11.6 mm (17% EDTA), 5.5 mm (0.5% NaOCl), 12.9 mm (1% NaOCl), 22.1 mm (2.5% NaOCl), and 28.5 mm (5.25% NaOCl). The mean diameters of the inhibition zones for E. faecalis were 2.8 mm (1% NaOCl), 5.4 mm (2.5% NaOCl), and 8.3 mm (5.25% NaOCl). For S. aureus, the mean values were 8.0 mm (17% EDTA), 3.0 mm (1% NaOCl), 8.8 mm (2.5% NaOCl), and 10.0 mm (5.25% NaOCl). Most of the irrigant solutions presented effective antimicrobial activity against C. albicans. A high inhibitory effect on the metabolic activity of E. faecalis was detected when the microorganisms were incubated with 17% EDTA. The same result was reached when S. aureus was incubated in the presence of > 2.5% NaOCl. Altogether, these results indicate that 2.5% and 5.25% NaOCl are microbicides against S. aureus while 0.5% and 1% NaOCl are only microbiostatic against the tested bacteria. The 6% and 10% citric acid as well as 17% EDTA did not affect the viability of any of the assayed microorganisms.

Preventive effect of fluoridated orthodontic resins subjected to high cariogenic challenges.

The aim of the present study was to evaluate the in vitro caries preventive effect of fluoridated orthodontic resins under pH cycling with two types of acid demineralizing saliva. Brackets were bonded to 60 bovine incisors, using either Transbond Plus Color Change (n=30) or Orthodontic Fill Magic (n=30) orthodontic resins. Each group of resin was divided into 3 subgroups (n=10): immersion in remineralizing artificial saliva for 14 days, pH cycling with high cariogenic challenge in acid saliva with pH 5.5, and acid saliva with pH 4.5. After 14 days of pH cycling, the caries preventive effect on the development of white spot lesion was evaluated considering the presence of inhibition zones to white spot lesions using two scores: 0= absence and 1= presence. Kruskal Wallis and Mann-Whitney tests (a=0.05) were used. Formation of white spot lesions was observed only under pH cycling using acid saliva with pH 4.5; with Transbond Plus Color Change being significantly more effective (p<0.05) in preventing the appearance of white spot lesions effect than Orthodontic Fill Magic. The acidity of the demineralizing solution influenced the formation of white spot lesions around orthodontic brackets under highly cariogenic conditions. Transbond Plus Color Change resin presented higher caries preventive effect than Orthodontic Fill Magic.

Histopathologic and SEM analysis of primary teeth with pulpectomy failure

OBJECTIVE The objective of this study was to identify the probable factors associated with pulpectomy failure of primary teeth through qualitative analysis by histopathology (HIST) and scanning electron microscopy (SEM). STUDY DESIGN A longitudinal clinical investigation of the efficacy of pulpectomy in primary teeth with irreversible pulp changes was carried out with 133 teeth (66 children) evaluated up to 48 months. The overall success was 86.1% during follow-up. Of the 18 teeth extracted as a result of treatment failure, 8 presented sufficiently undamaged roots to be randomly selected for HIST (n = 4) and SEM (n = 4) analysis. RESULTS Necrotic tissue and chronic inflammatory cells were observed in all specimens submitted to HIST as external radicular resorption associated with Howships lacunae. SEM analysis showed apical and furcation areas heavily infected with microorganisms and Howships lacunae. CONCLUSION These findings suggest that the main factors responsible for pulpectomy failure were technique limitations associated with the morphological irregularities created by external/inflammatory resorption.

Antimicrobial effects of the combination of chlorhexidine and xylitol

Aims To assess the effect of combining 1% chlorhexidine varnish (CHX) with xylitol chewing gum (XYL) on Streptococcus mutans and biofilm levels in 6-8-year-old children.Design Randomised controlled study.Subjects and methods Eighty-two 6-8-year-old children were randomly divided into groups as follows: G1 (n = 20): xylitol chewing gum twice a day after breakfast and lunch; G2 (n = 20): xylitol gum as G1 plus chlorhexidine varnish application at the start of the study and after one and two months; G3 (n = 20): chlorhexidine varnish as G2; and G4 (n = 22): fluoride gel application at the start of the study and after one and two months. Microbiological tests were performed to assess Streptococcus mutans colony forming units (CFU) and the teeth of those children with moderate or higher CFU scores were examined for visible biofilm. CFU scores were categorised as follows: 0 = absence of S. mutans, 1 = low level (1-10 CFU), 2 = moderate level (11-100 CFU), 3 = high level (101-250 CFU), 4 = very high level (>250 CFU). Biofilm scores based on a scale from 0 (absence of biofilm) to 5 (thick biofilm firmly adhered to posterior and anterior teeth) were obtained.Results The biofilm reduction was greater in G2 and G3, with mean values of 3.38 and 3.17 to 1.79 and 1.88, respectively (p <0.05). All groups presented a reduction in the S. mutans levels. XYL + CHX showed the largest reduction throughout the study period, with 58.3% in the first month, 84.2% in the second and 92.9% at the end of the study.Conclusions The XYL + CHX combination was efficient and superior to single treatments in controlling biofilm and suppressing S. mutans.

The influence of smear layer removal on primary tooth pulpectomy outcome: a 24-month, double-blind, randomized, and controlled clinical trial evaluation

BACKGROUND The effect of smear layer (SL) removal on primary tooth pulpectomy outcome has not been well elucidated. AIM To determine the effect of SL removal on primary tooth pulpectomy outcome. METHODS This is a double-blind, randomized, and controlled clinical trial. Forty-eight patients were randomly divided into SL removal (G1 = 40 teeth) or smear layer nonremoval (G2 = 42 teeth) groups. Following the chemomechanical preparation with K-files and 2.5% sodium hypochlorite (NaOCl), teeth were irrigated with either 6% citric acid and 0.9% physiologic solution (G1) or only 0.9% physiologic solution (G2). Camphorated paramonochlorophenol was used as intracanal medication. At the second appointment, 1 week after, root canals were filled with zinc oxide-eugenol paste. Clinical and radiographical baseline criteria were stipulated equally for both groups. RESULTS The success rate (G1 = 91.2%; G2 = 70.0%) was statistically different (P = 0.04) between the groups. In G2, the outcome was affected significantly by pulpal necrosis (P = 0.02), pre-operatory symptoms (P = 0.02), and periapical/inter-radicular radiolucency (P = 0.04). CONCLUSION The pulpectomy outcome was improved by smear layer removal. The outcome for teeth with pulpal necrosis, pre-operatory symptoms, or periapical/inter-radicular radiolucency was significantly improved by removal of the smear layer.

Mechanical properties of one and two-step fluoridated orthodontic resins submitted to different pH cycling regimes

The aim of this study is to assess the in vitro shear bond strength and adhesive remnant index (ARI) of one and two-step fluoridated orthodontic resins under conditions that simulate high cariogenic challenge. Edgewise brackets for maxillary central incisors were randomly bonded to 80 bovine incisors, using either Transbond Plus Color Change orthodontic resin and a self-etching primer adhesive (G1; n = 40) or Orthodontic Fill Magic with a conventional acid-etch technique (G2; n = 40). Each group of resin (n = 10) was divided into: immediate shear (A- pre-cycling control), immersion in artificial remineralizing saliva (neutral saliva) for 14 days (B- post-cycling control) and pH cycling with high cariogenic challenge (C- acid saliva with pH 5.5 and D- acid saliva with pH 4.5). After 14 days of pH cycling, the shear bond strength and ARI were evaluated. Considering the shear bond strength, Transbond Plus Color Change resin was stronger than Orthodontic Fill Magic when it was submitted to high cariogenic challenge (p < 0.05). Also Transbond Plus Color Change resin showed better adhesion to enamel than Orthodontic Fill Magic, in all situations evaluated (p < 0.05). It could be concluded that Transbond Plus Color Change resin presented better shear bond strength and adhesive remnant index when submitted to high cariogenic challenge, in comparison with Orthodontic Fill Magic.

O índice de necessidade de tratamento ortodôntico como um método de avaliação em saúde pública

Malocclusions are considered public health problems, needing a uniform method of assessment that prioritizes the attendance of individuals with greater orthodontic treatment need. Among the several oclusal indices developed with this purpose, the Index of Orthodontic Treatment Need has been used in many countries. As the demand for this treatment in public services in Brazil exceeds the offers, there is a need to implement an adequate method of patients selection. Thus, the aim of this article is to elucidate this index methodology and its benefits, because it can be very useful in orthodontic treatment referrals and triages.

Can the Enterococcus faecalis identified in the root canals of primary teeth be a cause of failure of endodontic treatment

Abstract Objective: This study investigated the presence of Enterococcus faecalis in primary teeth with primary root canal infections and related to the possible failure of pulpectomy outcome after 36 months. Material and methods: Root canal samples were obtained from 25 out of 244 patients using the sterile paper cone method. The identification of E. faecalis was done with culture and molecular tests using species-specific 16S rRNA gene-based polymerase chain reaction (PCR). After 36 months, the pulpectomy outcome was evaluated. Results: Enterococcus faecalis was found in five (20%) samples, and dental caries were the cause of primary infection in all of them. Pulpectomy outcome was evaluated only in teeth that completed the entire clinical protocol and were followed up to 36 months (n = 8). From these, 75% (n = 6) were successful and 25% (n = 2) failed. E. faecalis was present in 50% of both successful and failed cases. Conclusions: Enterococcus faecalis was not related to the failure of endodontic treatment of primary teeth.