Henrique Pretti

Association of functional gene polymorphism IL-1β in patients with external apical root resorption

INTRODUCTION External apical root resorption (EARR) is a frequent complication of orthodontic treatment. Interleukin 1beta (IL-1beta) is a potent stimulus for bone resorption and osteoclastic cell recruitment during orthodontic tooth movement. The purpose of this study was to assess the association between a polymorphism in the IL-1beta genes and EARR during orthodontic treatment. METHODS The sample included 61 Brazilian orthodontic patients, divided into 2 groups according to the presence (affected group, n = 23) or absence (control group, n = 38) of EARR in the central and lateral maxillary incisors in the posttreatment period. DNA was obtained from buccal swab cells. The polymorphism was analyzed by the polymerase chain reaction followed by digestion with restriction enzyme. The polymerase chain reaction products were analyzed in 10% polyacrylamide gel and stained with silver. RESULTS There were significant statistical differences (P <0.05) among the frequencies of the alleles and genotypes of the IL-1beta gene polymorphism between the affected and unaffected groups, suggesting that allele 1 predisposed the subjects to EARR (odds ratio = 4.0). CONCLUSIONS The polymorphism of the IL-1beta gene is associated with root resorption in the studied population.

The Dental Aesthetic Index and Dental Health Component of the Index of Orthodontic Treatment Need as Tools in Epidemiological Studies

The present study assesses the validity and reproducibility of two occlusal indices for epidemiological studies—the Dental Aesthetic Index (DAI) and the Dental Health Component of the Index of Orthodontic Treatment Need (DHC-IOTN) for the identification of orthodontic treatment needs. The total of 131 study models was examined by an examiner (orthodontic specialist) for the determination of the DAI and DHC-IOTN. Thirty days later, further assessment was performed to determine the reproducibility. The duration of each exam was measured in seconds with a stopwatch. The indices were compared by a panel of three experts in orthodontics to evaluate validity. The intra-examiner reliability evaluation resulted in an intraclass correlation coefficient of 0.89 for the DAI (95% CI = 0.64 to 1.0) and 0.87 for the DHC-IOTN (95% CI = 0.56 to 0.96). The time spent on the evaluation of the DHC-IOTN was less than the time spent on that of the DAI (P < 0.001). The accuracy of the indices, as reflected by the area under the receiver-operating characteristic curve, was 61% for the DAI (95% CI = 51 to 70; p = 0.037) and 67% for the DHC-IOTN (95% CI = 58 to 77; p = 0.001). Both indices presented good reproducibility and validity.

Kinetics of interleukin-6 and chemokine ligands 2 and 3 expression of periodontal tissues during orthodontic tooth movement.

INTRODUCTION Mechanical loading induces remodeling of the periodontal ligament and the alveolar bone and is mediated by cytokines and chemokines. In this study, we investigated the kinetics of interleukin-6 and chemokine ligands 2 and 3 levels in periodontal ligaments subjected to orthodontic forces. METHODS We used 64 premolars in this split-mouth design study. The experimental group consisted of premolars subjected to a force of 0.980 N in the apical direction for 3 hours, 15 hours, 3 days, 12 days, or 21 days with a 0.017 × 0.025-in beta-titanium alloy cantilever. The contralateral teeth, without orthodontic appliances, were used as controls. The premolars were extracted for orthodontic reasons, and the periodontal ligaments were scraped for analysis of cytokine levels by ELISA. RESULTS Compared with the control group, an increase in chemokine ligand 2 was observed on days 3 and 12, and increases in interleukin-6 and chemokine ligand 3 were observed on day 12 in the experimental group. CONCLUSIONS Our data demonstrated differential expressions of interleukin-6 and chemokine ligands 2 and 3 in periodontal ligaments after mechanical loading; this might reflect the distinct roles of these molecules in the bone remodeling process.

Difference in maxillary sinus volumes of patients with cleft lip and palate

BACKGROUND AND OBJECTIVE Sinus disease is noted to be common in patients with cleft lip and palate. Many have wondered if anatomic differences are a cause or at least a contributor of this. In this sense, comparisons of sinus volumes of patients with different craniofacial clefts may be helpful to determine possible differences from normal. Thus, the present study aimed to evaluate and compare the maxillary sinus volume of patients with unilateral (UCLP) and bilateral (BCLP) cleft lip and palate to control, i.e. non-cleft patients, using cone beam computed tomography (CBCT) images. METHODS The sample consisted of 30 subjects with UCLP, 15 with BCLP and 15 control individuals (non-cleft). Each maxillary sinus was assessed three-dimensionally, segmented and its volume was calculated. The comparison between right and left sinus was performed by Student t-test, and the differences between the control and cleft groups were calculated using ANOVA. RESULTS No statistical differences were found when the sides were compared (p>0.05). In relation to the assessment among groups, all comparisons had statistically significant differences (p<0.05), with the UCLP group presenting the lowest sinus volume. CONCLUSION UCLP individuals present maxillary sinuses with smaller volumes, without differences found between the cleft and non-cleft side. BCLP subjects also present a reduction in the volume when compared to a control sample, but the average sinus volume is larger than in UCLP patients.

GAND classification and volumetric assessment of unilateral cleft lip and palate malformations using cone beam computed tomography

The aim of this study was to propose a classification for unilateral cleft lip and palate (UCLP) malformations based on cone beam computed tomography (CBCT) images, as well as to estimate the amount of bone necessary for grafting, and to evaluate the relationship of this volume with scores obtained using the classification. CBCT images of 33 subjects with UCLP were evaluated according to gap, arch, nasal, and dental parameters (GAND classification). Additionally, these defects were segmented and the amount of graft needed for alveolar bone grafting was estimated. The reproducibility of GAND classification was analyzed by weighted kappa test. The association of volume assessment with the classification (gap and nasal parameters) was verified using analysis of variance, while the intra-observer agreement was analyzed using the intra-class correlation coefficient. The intra-observer reproducibility of the classification ranged from 0.29 to 0.92 and the inter-observer agreement ranged from 0.29 to 0.91. There were no statistically significant values when evaluating the association of the volume with the classification (P>0.05). The GAND classification is a novel system that allows the quick estimation of the extent and complexity of the cleft. It is not possible to estimate the amount of bone needed for alveolar bone grafting based on the classification; individualized surgical planning should be done for each patient specifically.

Three-dimensional evaluation of nasopharyngeal airways of unilateral cleft lip and palate patients.

The aim of this study was to compare the volume of nasopharyngeal airways of patients with unilateral cleft lip and palate (UCLP) with a control (noncleft) group of subjects.

Cytokine measurements in gingival crevicular fluid and periodontal ligament: Are they correlated?

INTRODUCTION Mechanical stress can induce molecular changes in gingival crevicular fluid (GCF) and the periodontal ligament (PDL). It is still not clear whether changes in the PDL and GCF are linked. In this study, we aimed to analyze the expression of cytokines in GCF and PDL after mechanical stress. METHODS Twenty-three healthy patients were included. The experimental group consisted of premolars subjected to a force of 0.980 N for 1, 3, 7, 14, 21, or 28 days. The contralateral teeth were the controls. GCF and PDL samples were collected at the same time points for analysis of cytokines using the cytometric bead array. RESULTS Interleukin (IL)-6 (IL-6) production was significantly elevated in the PDL on day 1 after force application. Significantly strong positive correlations between GCF and PDL in experimental group were seen on days 3 (interferon-gamma), 7 (IL-10), 14 (IL-17A), and 28 (IL-17A, tumor necrosis factor-alpha), and significantly strong negative correlation were seen on days 14 (interferon-gamma) and 21 (IL-2, IL-10). CONCLUSIONS Different patterns of IL-6 expression were seen in the PDL and GCF after mechanical stress. Despite occasional correlations between GCF and PDL, the molecular contributions of the PDL to the GCF changes could not be clearly defined by our model.

Risk variables of external apical root resorption during orthodontic treatment

INTRODUCTION: External apical root resorption (EARR) is an adverse outcome of the orthodontic treatment. So far, no single or associated factor has been identified as responsible for EARR due to tooth movement. OBJECTIVE: This study investigated the association of risk variables (age, gender, extraction for orthodontic treatment and Angle classification) with EARR and orthodontic treatment. METHOD: The sample (n=72) was divided into two groups according to presence (n=32) or absence (n=40) of EARR in maxillary central and lateral incisors after orthodontic treatment. RESULTS: There were no statistically significant differences in EARR according to age, gender, extraction or type of malocclusion (p>0.05). CONCLUSION: The risk variables examined were not associated with EARR in the study population.

Impact of malocclusion on the quality of life of children aged 8 to 10 years

ABSTRACT Objective: The aim of the present cross-sectional study was to assess the impact of malocclusion on the quality of life of children aged 8 to 10 years attending public elementary schools in Belo Horizonte, State of Minas Gerais, Brazil. Methods: The Brazilian version of the Child Perceptions Questionnaire 8-10 (CPQ8-10) was used to evaluate oral health-related quality of life. The children were examined for the diagnosis of malocclusion using the Dental Aesthetic Index (DAI). The data were analyzed by bivariate and multivariate descriptive statistics using Poisson regression at a 5% significance level. A total of 270 children participated in the study. Results: Children with normal occlusion or mild malocclusion (DAI ≤ 25) were 56% less likely (95%CI: 0.258-0.758; p= 0.003) to have their quality of life affected compared with children diagnosed with extremely severe malocclusion (DAI ≥ 36). Children with a maxillary anterior overjet ≥ 3 mm had higher CPQ8-10 mean scores (19.4; SD = 17.1) than those with an overjet < 3 mm (13.6; SD = 11.7; p= 0.038). Conclusions: Extremely severe malocclusion and pronounced maxillary anterior overjet were associated with a negative impact on quality of life.

Mini-implante como estratégia de tratamento para reabilitação protética temporária – relato de caso

A avulsao de incisivos permanentes gera um problema estetico e funcional para o paciente, e seu manejo clinico representa um desafio na odontologia. O sucesso do tratamento depende de varios fatores como a idade do paciente, a quantidade e qualidade ossea da regiao edentula, a discrepância ossea e o tipo de maloclusao encontrada. Ressalta-se a importância de minimizar efeitos colaterais nas unidades de ancoragem, garantindo ao mesmo tempo funcao e estetica ao longo dos tratamentos ortodontico e protetico, requeridos na maioria dos casos. O objetivo desse trabalho e apresentar atraves de um relato de caso clinico a versatilidade dos mini-implantes na reabilitacao temporaria de incisivos permanentes em individuos em fase de crescimento e desenvolvimento facial. Um menino de 9 anos que apresentava relacao de molar em classe I e mesializacao dos incisivos laterais, caninos e pre-molares superiores devido a ausencia dos elementos 11 e 21, que foram avulsionados, foi tratado; e ao final de 1 ano e 8 meses de tratamento, pode-se estabelecer uma intercuspidacao dentaria aceitavel e espaco adequado para confeccao das coroas provisorias sobre os parafusos. O acompanhamento radiografico foi realizado atraves de radiografias periapicais e panorâmicas. Na literatura os estudos mostram que os mini-implantes contribuem para a manutencao da quantidade e qualidade ossea do processo alveolar, reduzindo a necessidade de futuras cirurgias de enxerto antes da fixacao dos implantes osseointegrados. Dessa forma, esse caso mostrou que a ancoragem esqueletica com mini-implantes ortodonticos autorosqueaveis auxilia na reabilitacao de pacientes que ainda nao possuem uma idade ossea suficiente para receberem implantes dentarios osseointegrados.