Patient perception of orthodontists with different stereotypes: development, psychometric properties, and application of an assessment instrument.

INTRODUCTION: This research aimed to develop and validate a questionnaire that considers social judgments and, through its application, assesses whether the presence of piercings, tattoos, beards, and loose hair visible in the face and neck region reflect on the patient perception regarding characteristics of the orthodontist's professional scope. METHODS: The developed questionnaire had its psychometric properties evaluated and was applied to 220 young people and adults, aged 18-70 years, who responded according to their perception of 12 manipulated images of orthodontists with different stereotypes, considering the following items: hygiene, care, punctuality, experience and knowledge in orthodontics. RESULTS: The developed questionnaire showed high acceptability, confirmed reliability and validity of the construct, and satisfactory internal consistency. The stereotype interfered with the perception of professionalism (P <0.01), in which the orthodontist with combined characteristics (beard/loose hair, piercing, earrings, and tattoo) obtained the lowest mean scores, both for each item of the questionnaire individually (P <0.01) and in total (P <0.01). Health professional (P = 0.427) and educational level (P = 0.285) status did not influence the perception; however, there was a significant difference for the age groups (P = 0.041). CONCLUSIONS: The developed questionnaire proved to be valid and reliable for application. Orthodontists with piercings and tattoos on the face and neck were considered less professional. Being a health professional and educational level status did not influence the perception. However, older subjects (aged 51-70 years) were more critical in judging stereotypes than younger subjects (aged 18-30 years).

Emoji as promising tools for emotional evaluation in orthodontics.

BACKGROUND: Emoji are pictograms frequently used in social networks capable of expressing emotions. These tools can provide insights into people's behavior that could not be obtained with the use of textual communication. Recently, emoji have been introduced to various research fields as successful alternatives to word-based questionnaires for measure emotional responses. The objective of this study was to preliminarily evaluate the discriminating ability and relationship of these tools with different occlusal conditions/malocclusions. METHODS: Online surveys were applied to adult individuals (n = 201; mean age = 27.4 ± 5.7; 37.3% males, 62.7% females). Subjects issued acceptance scores (10-point scale) and expressed their emotional status using a 30-emoji list in relation to nine occlusal conditions: C1-crowding, C2-anterior open bite, C3-interincisal diastema, C4-increased overjet + deep bite (Class II div. 1), C5-anterior crossbite (Class III), C6-ideal occlusion, C7-unilateral posterior crossbite, C8-anterior open bite plus bilateral posterior crossbite plus crowding, and C9-deep bite (Class II div. 2). Cochran's Q and McNemar tests were used to compare the frequencies of choice of emoji between conditions. Correspondence analyses were applied to assess the association between occlusal conditions and emoji. Kendall's correlation coefficient was calculated to evaluate the relationship between mean acceptance scores and frequency counts of each emoji. RESULTS: The frequency of choice between conditions showed a significant difference for 25 of the 30 emoji (P < 0.05), indicating an adequate discriminating ability of these tools. Emoji were grouped predominantly based on their emotional valence (positive/negative) and arousal/activation (high/low). Positive emoji were associated with the most accepted conditions (i.e., C6, C3), while negative emoji with the most rejected ones (i.e., C8, C1, C2). Although only weak, positive correlations between acceptance and positively valenced emoji, and negative correlations between acceptance and negatively valenced emoji were observed (P < 0.05). CONCLUSIONS: Emoji have an adequate discriminatory ability and would allow determining emotional profiles in the face of different occlusal conditions. Further research is necessary to consolidate the use of these tools in an instrument that allows measuring emotional responses.

Collagen membrane and distraction osteogenesis for correcting alveolar bone defects: An animal pilot study.

BACKGROUND: The objective of this study was to evaluate the applicability of distraction osteogenesis with or without collagen membrane coverage to approximate the bone surfaces surrounding alveolar defects in pigs. METHODS: The sample comprised six pigs. One animal was control, and in the other five, alveolar bone defects were created and distraction osteogenesis was carried out to approximate adjacent bone surfaces in the defect site. Resorbable membranes were placed to cover the alveolar defects on one palatal side of the experimental animals. Radiographs were taken, and the histology was studied in each bone defect site at the 2nd, 9th, 16th, 23rd, and 46th days of healing. RESULTS: The radiographs showed that the alveolar bone defects were successfully corrected. Initial osteogenesis was delayed, but bone bridge formation was complete in the membrane-covered samples at the 46th day of healing. In the other group, bone bridge formation was incomplete at the end of the study. CONCLUSIONS: Distraction osteogenesis was effective in approximating transported bones to host bones. The resorbable membranes produced complete bone bridges in the approximation sites.

Stress and displacement of mini-implants and appliance in Mini-implant Assisted Rapid Palatal Expansion: analysis by finite element method.

OBJECTIVE: In this study, simulations were performed by the finite element method (FEM) to determine the tension and displacement in mini-implants and in expander appliance during rapid maxillary expansion, by varying the number and location of the mini-implants. METHODS: For the computational simulation, a three-dimensional mesh was used for the maxilla, mini-implants and expander appliance. Comparisons were made on six different Mini-implant Assisted Rapid Palatal Expander (MARPE) configurations, by varying the amount and location of mini-implants. A closed suture was design and received two activations of 0.25 mm, and an open suture had a 0.5-mm aperture that received 20 activations, also of 0.25 mm. RESULTS: For the closed suture, the maximum displacement values in the mini-implants were between 0.253 and 0.280 mm, and stress was between 1,348.9 and 2,948.2 MPa; in the expander appliance, the displacement values were between 0.256 and 0.281 mm, and stress was between 738.52 and 1,207.6 MPa. For the open suture, the maximum displacement values in the mini-implants were between 2.57 and 2.79 mm, and stress was between 5,765.3 and 10,366 MPa; in the appliance, the maximum displacements was between 2.53 and 2.89 mm, and stress was between 4,859.7 and 9,157.4 MPa. CONCLUSIONS: There were higher stress concentrations in the mini-implant than in the expander arm. In the simulations with a configuration of three mini-implants, stress overload was observed in the isolated mini-implant. Displacements of the mini-implants and arms of the appliance were similar in all simulations.

Orthodontic camouflage as a treatment alternative for skeletal Class III.

INTRODUCTION: Skeletal Class III malocclusion is a deformity of complex treatment, with few intervention alternatives, which are further limited in nongrowing patients. In most cases, orthognathic surgery is the ideal treatment for adults, an option often refused by patients. Mild to moderate skeletal Class III malocclusions and acceptable facial esthetics can benefit from a course of treatment in which dental movements are used to compensate for the skeletal discrepancy. OBJECTIVE: This study aimed to discuss orthodontic camouflage as an option for adult patients with Class III malocclusion, emphasizing its indications, implications and expected results.

Chromatic analysis of orthodontic resin bonding agents exposed to different antiseptic mouthrinses.

OBJECTIVE: To assess the color of different orthodontic resin bonding agents exposed to three antiseptic mouthrinses for a prolonged time interval (10-year aging simulation). METHODS: 160 specimens were distributed into four groups, according to the orthodontic resin bond agent (Concise, Transbond XT, Transbond Plus Color Change, and Natural Ortho). Each group was exposed to different antiseptic mouthrinses: alcohol-based (Listerine®), alcohol-free (Oral-B®), chlorhexidine (Periogard®) and distilled water as the control. Specimens were submitted to two cycles of staining and artificial aging. Color was evaluated by means of a digital spectrophotometer at the beginning of the experiment and after every cycle. The system used to assess color changes was the CIE L*a*b*. Data was analyzed using the ANOVA and Tukey post-hoc test. RESULTS: After simulation of 10 years of aging, Transbond XT and Natural Ortho composites presented no statistically significant differences in ∆E when exposed to different mouthrinses. The Concise composite specimens exposed to alcohol-free mouthrinse presented a significant difference when compared with specimens from the same group exposed to other antiseptic mouthrinses. Transbond Plus Color Change specimens exposed to chlorhexidine mouthrinse and to alcohol-containing mouthrinse presented a significant difference when compared with the specimens from the group exposed to water and alcohol-free antiseptic. CONCLUSION: All orthodontic resin bonding agents tested presented clinically perceptible color changes when exposed to at least one of the mouthrinses, except for the Natural Ortho composite. The Concise composite exposed to the alcohol-free solution was the resin that presented the highest color change values.

Reasons influencing the preferences of prospective patients and orthodontists for different orthodontic appliances.

OBJECTIVE: To evaluate the reasons influencing the preferences for a certain type of orthodontic appliance over another among prospective patients (PP) and orthodontists. METHODS: A total of 49 PP and 51 orthodontists were asked about their preferences for the following appliances: clear aligners (CA), lingual metallic brackets (LMB), polycrystalline and monocrystalline ceramic brackets, and buccal metallic brackets (BMB). The participants rated the importance of 17 potential reasons that would explain their choices. The reasons that contributed most to these preferences were identified. Non-parametric tests (Fisher's exact, χ2 and Mann-Whitney tests) and multivariate analyses (regression and discriminant analysis) were used to assess the data (α = 0.05). RESULTS: CA and BMB were the most chosen appliances by PP and orthodontists, respectively. LMB was the most rejected option among both groups of participants (p < 0.001). Rates of the importance of pain/discomfort, smile esthetics, finishing details, and feeding/speech impairment showed the highest differences between PP and orthodontists (p < 0.0005). Discriminant analyses showed that individuals who considered treatment time and smile esthetics as more important were more likely to prefer CA, while those who prioritized finishing details and cost were more likely to choose BMB (p < 0.05). CONCLUSIONS: Reasons related to comfort and quality of life during use were considered as more important by PP, while those related to the results and clinical performance of the appliances were considered as more relevant by orthodontists.

FGF10 and FGF13 genetic variation and tooth-size discrepancies.

OBJECTIVES: To explore whether variations in odontogenesis-related genes are associated with tooth-size discrepancies. MATERIALS AND METHODS: Measurements of the width of permanent teeth were obtained from dental casts of 62 orthodontic patients (age 15.65 ± 6.82 years; 29 males and 33 females). Participants were classified according to the anterior and overall Bolton ratios as without tooth-size discrepancy or with maxillary or mandibular tooth-size excess. Genomic DNA extracted from buccal cells was used, and 13 single nucleotide polymorphisms (SNPs) across nine genes were genotyped by polymerase chain reaction using TaqMan chemistry. χ2 or Fisher exact tests were applied to determine the overrepresentation of genotypes/alleles depending on the type of tooth-size discrepancy (α = .05; corrected P value: P < 5.556 × 10-3). Odds ratios (ORs) and their correspondent 95% confidence intervals (CIs) were also calculated to investigate the risk of this phenotype for the SNPs having significant association. RESULTS: Individuals carrying the FGF10 rs900379 T allele were more likely to have larger mandibular teeth (OR = 3.74; 95% CI: 1.65-8.47; P = .002). This effect appeared to be stronger when two copies of the risk allele (TT) were found (recessive model, OR = 6.16; 95% CI: 1.71-22.16; P = .006). On the other hand, FGF13 rs5931572 rare homozygotes (AA, or male A hemizygotes) had increased risk of displaying tooth-size discrepancies when compared with the common homozygotes (GG, or male G hemizygotes; OR = 10.32; 95% CI: 2.20-48.26; P = .003). CONCLUSIONS: The results suggest that FGF10 and FGF13 may contribute to the presence of tooth-size discrepancies.

Orthodontic camouflage as a treatment alternative for skeletal Class III

ABSTRACT Introduction: Skeletal Class III malocclusion is a deformity of complex treatment, with few intervention alternatives, which are further limited in nongrowing patients. In most cases, orthognathic surgery is the ideal treatment for adults, an option often refused by patients. Mild to moderate skeletal Class III malocclusions and acceptable facial esthetics can benefit from a course of treatment in which dental movements are used to compensate for the skeletal discrepancy. Objective: This study aimed to discuss orthodontic camouflage as an option for adult patients with Class III malocclusion, emphasizing its indications, implications and expected results.

RESUMO Introdução: A má oclusão esquelética de Classe III é uma deformidade de difícil tratamento e com poucas alternativas de intervenção, que ficam ainda mais limitadas em pacientes sem crescimento. Na maior parte dos casos, o tratamento ideal para adultos é a cirurgia ortognática, opção muitas vezes recusada pelo paciente. As más oclusões esqueléticas de Classe III leve a moderada e com estética facial aceitável podem se beneficiar de um plano de tratamento no qual movimentações dentárias são realizadas para compensar a discrepância esquelética. Objetivo: O objetivo do presente estudo foi discutir a camuflagem ortodôntica como opção para pacientes adultos com má oclusão de Classe III, ressaltando suas indicações, implicações e resultados esperados.

Chromatic analysis of orthodontic resin bonding agents exposed to different antiseptic mouthrinses

ABSTRACT Objective: To assess the color of different orthodontic resin bonding agents exposed to three antiseptic mouthrinses for a prolonged time interval (10-year aging simulation). Methods: 160 specimens were distributed into four groups, according to the orthodontic resin bond agent (Concise, Transbond XT, Transbond Plus Color Change, and Natural Ortho). Each group was exposed to different antiseptic mouthrinses: alcohol-based (Listerine®), alcohol-free (Oral-B®), chlorhexidine (Periogard®) and distilled water as the control. Specimens were submitted to two cycles of staining and artificial aging. Color was evaluated by means of a digital spectrophotometer at the beginning of the experiment and after every cycle. The system used to assess color changes was the CIE L*a*b*. Data was analyzed using the ANOVA and Tukey post-hoc test. Results: After simulation of 10 years of aging, Transbond XT and Natural Ortho composites presented no statistically significant differences in ∆E when exposed to different mouthrinses. The Concise composite specimens exposed to alcohol-free mouthrinse presented a significant difference when compared with specimens from the same group exposed to other antiseptic mouthrinses. Transbond Plus Color Change specimens exposed to chlorhexidine mouthrinse and to alcohol-containing mouthrinse presented a significant difference when compared with the specimens from the group exposed to water and alcohol-free antiseptic. Conclusion: All orthodontic resin bonding agents tested presented clinically perceptible color changes when exposed to at least one of the mouthrinses, except for the Natural Ortho composite. The Concise composite exposed to the alcohol-free solution was the resin that presented the highest color change values.

RESUMO Objetivo: Avaliar a cor de diferentes resinas ortodônticas expostas a três enxaguantes bucais, por um intervalo de tempo prolongado (simulação de 10 anos de envelhecimento). Métodos: 160 espécimes foram distribuídos em quatro grupos, de acordo com a resina de colagem ortodôntica (Concise, Transbond XT, Transbond Plus Color Change e Natural Ortho). Cada grupo foi exposto a diferentes tipos de enxaguantes bucais: à base de álcool (Listerine®), isento de álcool (Oral-B®), clorexidina (Periogard®) ou água destilada, como controle. Os espécimes foram submetidos a dois ciclos de manchamento e envelhecimento artificial. A cor foi avaliada por meio de um espectrofotômetro digital no início do experimento e após cada ciclo. O sistema utilizado para avaliar as alterações de cor foi o CIE L*a*b*. Os dados foram analisados utilizando-se o teste ANOVA e o teste post-hoc de Tukey. Resultados: Após a simulação de 10 anos de envelhecimento, as resinas Transbond XT e Natural Ortho não apresentaram diferenças estatisticamente significativas no ∆E, quando expostas a diferentes enxaguantes bucais. Os espécimes do grupo Concise expostos ao enxaguante bucal sem álcool apresentaram diferença significativa quando comparados aos espécimes do mesmo grupo expostos aos outros enxaguantes bucais. Os espécimes do grupo Transbond Plus Color Change expostos à clorexidina e ao enxaguante bucal à base de álcool apresentaram diferença significativa quando comparados aos espécimes dos grupos expostos à água e ao enxaguante bucal sem álcool. Conclusão: Todas as resinas ortodônticas avaliadas apresentaram alterações de cor clinicamente perceptíveis quando expostas a pelo menos um dos enxaguantes bucais, com exceção da resina ortodôntica Natural Ortho. A resina Concise exposta à solução isenta de álcool foi a que apresentou os maiores valores de alteração de cor.

Influence of cigarette smoke on enamel color stability after orthodontic debonding: an in vitro study

Objective: The aim of this study was to evaluate the color stability of dental enamel exposed to cigarette smoke after orthodontic debonding. Methods: Thirty-two bovine incisors were allocated into control (C1 and C2) and experimental groups (n=8) according to distinct bonding protocols: with adhesive (B1) and without adhesive (B2) and exposure to cigarette smoke. Samples from B1, B2 and C2 were exposed to ten cycles of smoke in a specific and hermetic chamber while the C1 remained stored in artificial saliva. Color analysis was performed with a spectrophotometer according to the L*a*b* system. Intergroup comparisons and effect of time were estimated with ANOVA/Tukey and paired Student t tests, respectively (a=0.05). Results: Statistically significant color changes have not been observed in C1 (L*: -0.69 ± 0.80; a*: 0.36 ± 0.23; b*: 0.17 ± 0.50) and without adhesive (B2) (L*: -3.74 ± 2.85; a*: 0.93 ± 0,73; b*: 1.13 ± 1.16) through the study time (p>0,05). However, the group with adhesive (B1) presented significant color changes in L*:-5.55 ± 2.28, a*: 2.33 ± 0.77 and b*: 3.30 ± 1.37, what means, darker, greener and more yellow, respectively (p<0,05) and the control group that was exposed to the cigarette smoke (C2) presented significant color changes in L*: -1.72 ± 0.28 e b*: 1.82 ± 0.22, what means, darker and more yellow, respectively. Conclusion: Enamel color stability was affected by exposure to cigarette smoke after orthodontic debonding, especially when bonding protocolcomprised the application of primer adhesive.

Objetivo: O objetivo deste estudo foi avaliar a estabilidade da cor do esmalte dentário exposto à fumaça de cigarro após a descolagem ortodôntica. Métodos: Trinta e dois incisivos bovinos foram alocados nos grupos controle (C1 and C2) e experimental (n = 8) de acordo com protocolos de colagem ortodôntica distintos: com adesivo (B1) e sem adesivo (B2) e expostos à fumaça de cigarro. Amostras do B1, B2 e C2 foram expostas a dez ciclos de fumaça em uma câmara específica e hermética, enquanto o C1 permaneceu armazenado em saliva artificial. A análise da estabilidade de cor foi realizada com um espectrofotômetro de acordo com osistema L* a* b*. As comparações intergrupos e o efeito do tempo foram verificados com ANOVA / Tukey e testes t de Student, respectivamente (a=0,05). Resultados: Não foram observadas alterações de cor estatisticamente significativas no C1 (L*: -0,69 ± 0,80; a*: 0,36 ± 0,23; b*: 0,17 ± 0.50) e sem adesivo (B2) (L*: -3,74 ± 2,85; a*: 0,93 ± 0,73; b *: 1,13 ± 1,16) durante o tempo de estudo (p>0,05). No entanto, o grupo com adesivo (B1) apresentou alterações significativas de cor em L*: - 5,55 ± 2,28, a*: 2,33 ± 0,77 eb*: 3,30 ± 1,37, o que significa, mais escuro, mais verde e mais amarelo, respectivamente (p<0,05) e o grupo controle exposto à fumaça de cigarro (C2) apresentou alterações significativas de cor em L*: -1,72 ± 0,28 e b*: 1, 82 ± 0,22, o que significa, mais escuro e mais amarelo, respectivamente. Conclusão: A estabilidade da cor do esmalte foi afetada pela exposição à fumaça de cigarro após a descolagem ortodôntica, principalmente quando o protocolo de colagem incluía a aplicação de adesivo.

Impaction of mandibular canine associated with a dentigerous cyst: a 2. 5 - year follow-up report

Introduction: Dentigerous cyst is an odontogenic cyst lesion surrounding the crown of an unerupted or impacted tooth in the jaw. Objective: The aim of this case report is to describe the treatment planning and follow-up of a dentigerous cyst associated with the impaction of the permanent mandibular right canine tooth in an 11-year-old female. Case report: Radiographic assessment revealed a radiolucent unilocular round-shaped lesion localized in the mandibular symphysis. Enucleation was performed and the affected tooth was removed under general anesthesia. The patient is under follow-up due to orthodontic treatment. The affected area healed without complications. Conclusion: Two and a half years after the enucleation, the cyst had totally disappeared, and no recurrences were observed. Bone remodeling and neoformation were noticed.

Introdução: O cisto dentígero é uma lesão odontogênica ao redor da coroa de um dente não irrompido ou impactado na mandíbula. Objetivo: O objetivo deste relato de caso é descrever o plano do tratamento e o acompanhamento de um cisto dentígero associado à impactação do canino permanente inferior direito em uma criança do gênero feminino de 11 anos de idade. Relato do caso: A avaliação radiográfica revelou lesão unilocular radiolúcida de forma arredondada, localizada na sínfise mandibular. A enucleação foi realizada e o dente afetado foi removido sob anestesia geral. A paciente encontra-se em acompanhamento devido o tratamento ortodôntico. A área afetada curou sem complicações. Conclusão: Dois anos e meio após a enucleação, o cisto desapareceu totalmente e não houve recidivas. Remodelação óssea e neoformação foram observadas.

Possible association between craniofacial dimensions and genetic markers in ESR1 and ESR2.

OBJECTIVE: To investigate the association of genetic markers in ESR1 and ESR2 with craniofacial measurements. DESIGN: Cross-sectional study. SETTING: School of Dentistry of Ribeirão Preto, University of São Paulo. PARTICIPANTS: A total of 146 biologically unrelated, self-reported Caucasian Brazilians with no syndromic conditions were included. METHODS: Sagittal and vertical measurements (ANB, S-N, Ptm'-A', Co-Gn, Go-Pg, N-Me, ANS-Me, S-Go and Co-Go) from lateral cephalograms were examined for craniofacial evaluation. DNA was extracted from saliva and genetic markers in ESR1 (rs2234693 and rs9340799) and in ESR2 (rs1256049 and rs4986938) were analysed by real-time polymerase chain reaction. Hardy-Weinberg equilibrium was evaluated using the Chi-square test within each marker. The associations between craniofacial dimensions and genotypes were analysed by linear regression and adjusted by sex and age. The established alpha was 5%. RESULTS: Individuals carrying CC in ESR1 rs2234693 had a decrease of -3.146 mm in ANS-Me (P = 0.044). In addition, rs4986938 in ESR2 was associated with S-N measurement (P = 0.009/ ß = -3.465). This marker was also associated with Go-Pg measurement, in which the CC genotype had a decrease of -3.925 mm in the length of the mandibular body (P = 0.043). CONCLUSION: The present study suggests that in ESR1 and ESR2 are markers for variations in the craniofacial dimensions. However, further research should confirm the results.

Analysis of the middle region of the pharynx in adolescents with different anteroposterior craniofacial skeletal patterns.

OBJECTIVE: To assess the volume and morphology of the middle region of the pharynx (MRP) in adolescents with different anteroposterior craniofacial skeletal patterns. METHODS: One hundred twenty-six patients (56 male and 70 female), who had cone-beam computed tomography (CBCT) within their records, were selected for this cross-sectional study. Participants were classified, according to their ANB angle value, in Class I (1o ≤ ANB ≤ 3o), Class II (ANB > 3o) and Class III (ANB < 1o). The total volume (tV), minimum axial area (AxMin) and morphology of the MRP and its subdivisions - velopharynx (VP) and oropharynx (OP) - were characterized by CBCT and 3-dimensional image reconstruction software. Intergroup comparisons were performed by ANOVA and Tukey post-hoc tests. Correlations between tV and Axmin with the ANB angle values were tested using linear regression analysis, considering sex as covariable. RESULTS: Statistically significant difference between groups were observed in tV only for the VP region; Class II individuals presented significantly lower tV (6863.75 ± 2627.20 mm3) than Class III subjects (9011.62 ± 3442.56 mm3) (p< 0.05). No significant differences were observed between groups for any other variable assessed, neither in MRP nor in the OP region (p> 0.05). A significant negative correlation was evidenced between tV and Axmin and the ANB angle values; sexual dimorphism was observed for some variables. CONCLUSIONS: Class II subjects have smaller tV in the VP region. tV and Axmin tend to decrease in all evaluated regions when the ANB angle values increase.

Analysis of the middle region of the pharynx in adolescents with different anteroposterior craniofacial skeletal patterns

ABSTRACT Objective: To assess the volume and morphology of the middle region of the pharynx (MRP) in adolescents with different anteroposterior craniofacial skeletal patterns. Methods: One hundred twenty-six patients (56 male and 70 female), who had cone-beam computed tomography (CBCT) within their records, were selected for this cross-sectional study. Participants were classified, according to their ANB angle value, in Class I (1o ≤ ANB ≤ 3o), Class II (ANB > 3o) and Class III (ANB < 1o). The total volume (tV), minimum axial area (AxMin) and morphology of the MRP and its subdivisions - velopharynx (VP) and oropharynx (OP) - were characterized by CBCT and 3-dimensional image reconstruction software. Intergroup comparisons were performed by ANOVA and Tukey post-hoc tests. Correlations between tV and Axmin with the ANB angle values were tested using linear regression analysis, considering sex as covariable. Results: Statistically significant difference between groups were observed in tV only for the VP region; Class II individuals presented significantly lower tV (6863.75 ± 2627.20 mm3) than Class III subjects (9011.62 ± 3442.56 mm3) (p< 0.05). No significant differences were observed between groups for any other variable assessed, neither in MRP nor in the OP region (p> 0.05). A significant negative correlation was evidenced between tV and Axmin and the ANB angle values; sexual dimorphism was observed for some variables. Conclusions: Class II subjects have smaller tV in the VP region. tV and Axmin tend to decrease in all evaluated regions when the ANB angle values increase.

RESUMO Objetivo: avaliar o volume e a morfologia da porção média da faringe (PMF) em adolescentes com diferentes padrões esqueléticos no sentido anteroposterior. Método: para esse estudo transversal, foram selecionados cento e vinte e seis pacientes (56 homens e 70 mulheres) que tinham tomografia computadorizada de feixe cônico (TCFC) em seus registros. Os participantes foram classificados de acordo com o valor do ângulo ANB, em Classe I (1o ≥ ANB ≤ 3o), Classe II (ANB > 3o) e Classe III (ANB < 1o). O volume total (Vt), a área axial mínima (AxMin) e a morfologia da PMF e de suas subdivisões - velofaringe (VF) e orofaringe (OF) - foram avaliados na TCFC e em software de reconstrução tridimensional (3D) de imagens. As comparações intergrupos foram realizadas por meio dos testes ANOVA e post-hoc de Tukey. As correlações entre os valores de Vt e Axmin das vias aéreas com os valores do ângulo ANB foram testadas por meio de análise de regressão linear, considerando-se o sexo como uma covariável. Resultados: diferença estatisticamente significativa entre os grupos foi observada apenas no Vt da VF; indivíduos Classe II apresentaram Vt significativamente menor (6.863,75 ± 2.627,20 mm3) do que indivíduos Classe III (9.011,62 ± 3.442,56 mm3) (p< 0,05). Não foram observadas diferenças significativas entre os grupos em nenhuma outra variável avaliada, nem na PMF, nem na OF (p> 0,05). Foi evidenciada uma correlação negativa significativa entre Vt e Axmin e os valores do ângulo ANB; dimorfismo sexual foi observado para algumas variáveis. Conclusões: indivíduos Classe II apresentam o menor Vt da VF. O Vt e a Axmin tenderam a diminuir quando os valores do ângulo ANB aumentaram, em todas as regiões avaliadas.

Genetic polymorphism in ESR2 and risk of tooth agenesis

Introduction: Tooth agenesis (TA) is the congenital absence of teeth. Several studies have proposed a strong genetic background for this condition. Aim: The present cross-sectional study aimed to evaluate whether genetic polymorphisms in the genes that code for estrogen receptors ( ESR1 and ESR2 ) are associated with the presence of isolated TA in a Brazilian sample. Methods: Panoramic radiographs of 142 orthodontic patients were assessed to determine TA of permanent teeth (excluding third molars). DNA of patients was extracted from buccal cells from saliva to evaluate genetic polymorphisms in ESR1 ( rs2234693 and rs9340799 ) and ESR2 ( rs1256049 and rs4986938 ) by genotyping using the real-time PCR technique. For statistical analyses, associations between the distributions of the alleles and genotypes, and the ocurrence of TA were assessed for each genetic polymorphism, with an established alpha of 5%. Results: Thirteen patients had at least 1 congenital missing tooth. The number of congenitally missing teeth ranged from 1 to 11. The genetic polymorphisms rs2234693 and rs9340799 in ESR1 and rs1256049 in ESR2 were not associated with TA ( p > 0.05) . For the genetic polymorphism rs4986938 in ESR2, the genotype and allele distributions were significantly different between the patients with and without TA ( p < 0.05). The CC genotype and the C allele were overrepresented in the TA patients. Conclusion: The genetic polymorphism rs4986938 in ESR2 was associated with the ocurrence o f TA.

Introdução: A agenesia dentária (AD) é a ausência congênita de um ou mais dentes. Vários estudos vêm sugerindo o forte componente genético para essa condição. Objetivo: O presente estudo teve como objetivo avaliar se os polimorfismos genéticos nos genes que codificam os receptores de estrógeno ( ESR1 e ESR2 ) estão associados à ocorrrência de AD isolada em uma amostra brasileira. Métodos: Radiografias panorâmicas de 142 pacientes ortodônticos foram avaliadas para determinar AD de dentes permanentes (excluindo terceiros molares). O DNA dos pacientes foi extraído das células da mucosa bucal contidas na saliva para avaliar polimorfismos genéticos em ESR1 ( rs2234693 e rs9340799 ) e ESR2 ( rs1256049 e rs4986938 ) por genotipagem usando a técnica de PCR em tempo real. Para análises estatísticas, associações entre as distribuições dos alelos e genótipos e a ocorrrência de AD foram avaliadas para cada polimorfismo genético, com um alfa estabelecido de 5%. Resultados: Treze pacientes tiveram pelo menos 1 dente congenitamente ausente. O número de dentes congenitamente ausentes variou de 1 a 11. Os polimorfismos genéticos rs2234693 e rs9340799 no ESR1 e rs1256049 no ESR2 não foram associados à AD ( p > 0,05). Para o polimorfismo genético rs4986938 no ESR2 , as distribuições dos genótipos e dos alelos foram estatisticamente diferentes entre os pacientes com e sem AD ( p < 0,05). O genótipo CC e o alelo C estavam super-representados nos pacientes com AD. Conclusão: Houve associação entre o polimorfismo genético rs4986938 no ESR2 e a ocorrrência de AD.

High-intensity laser application in Orthodontics

ABSTRACT Introduction: In dental practice, low-level laser therapy (LLLT) and high-intensity laser therapy (HILT) are mainly used for dental surgery and biostimulation therapy. Within the Orthodontic specialty, while LLLT has been widely used to treat pain associated with orthodontic movement, accelerate bone regeneration after rapid maxillary expansion, and enhance orthodontic tooth movement, HILT, in turn, has been seen as an alternative for addressing soft tissue complications associated to orthodontic treatment. Objective: The aim of this study is to discuss HILT applications in orthodontic treatment. Methods: This study describes the use of HILT in surgical treatments such as gingivectomy, ulotomy, ulectomy, fiberotomy, labial and lingual frenectomies, as well as hard tissue and other dental restorative materials applications. Conclusion: Despite the many applications for lasers in Orthodontics, they are still underused by Brazilian practitioners. However, it is quite likely that this demand will increase over the next years - following the trend in the USA, where laser therapies are more widely used.

High-intensity laser application in Orthodontics.

INTRODUCTION: In dental practice, low-level laser therapy (LLLT) and high-intensity laser therapy (HILT) are mainly used for dental surgery and biostimulation therapy. Within the Orthodontic specialty, while LLLT has been widely used to treat pain associated with orthodontic movement, accelerate bone regeneration after rapid maxillary expansion, and enhance orthodontic tooth movement, HILT, in turn, has been seen as an alternative for addressing soft tissue complications associated to orthodontic treatment. OBJECTIVE: The aim of this study is to discuss HILT applications in orthodontic treatment. METHODS: This study describes the use of HILT in surgical treatments such as gingivectomy, ulotomy, ulectomy, fiberotomy, labial and lingual frenectomies, as well as hard tissue and other dental restorative materials applications. CONCLUSION: Despite the many applications for lasers in Orthodontics, they are still underused by Brazilian practitioners. However, it is quite likely that this demand will increase over the next years - following the trend in the USA, where laser therapies are more widely used.