Class II subdivision treatment and stability with asymmetric Herbst appliance: A case report.

Non-surgical treatment of Class II subdivision may involve complex mechanics or asymmetric tooth extraction in its resolution. This report demonstrates the result and the short-term stability of Class II subdivision treated with asymmetrically installed Herbst appliance followed by conventional fixed orthodontic appliance. The approach allowed the correction of the unilateral Class II molar relationship and increased overjet, as well as the deviation of dental midlines, with improvement in lip posture and facial profile. The results remained stable two years after treatment, confirming the treatment success.

Redirection of palatally ectopic maxillary canines: Case report and proposition of an interceptive sequential guideline.

The eruptive deviation of the permanent maxillary canine must be identified early, at the beginning of the second transitional period of the mixed dentition. Acting at this moment is fundamental for its spontaneous redirection and eruption. The aim of the paper is to present a case where the extraction of the deciduous canines was the choice for redirecting the maxillary permanent canines with eruptive palatal deviation, as well as to suggest a sequence of procedures for diagnosis and choice of treatment. The success of deciduous canine extraction in redirecting the ectopic permanent canines is discussed in this case, as well as aspects that might lead to failure. Still, it highlights the importance of computed tomography for choosing conservative treatment or traction, including it in the sequential guideline for acting in these cases.

Pain perception and expectation related to interradicular mini-implants insertion: a systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review was to compare the expectation and perception of pain reported by patients before and after the installation of interradicular mini-implants. MATERIALS AND METHODS: Electronic search was performed in six databases. Inclusion criteria were randomized controlled trials (RCTs) or non-randomized controlled clinical trials (nRCTs); studies using mini-implants in the interradicular region; assessment of pain intensity by visual analogue or numerical scale. The risk of bias assessment was based on the Rob 2 tool and Robins-I. RESULTS: A total of 1566 articles were retrieved, and 21 met the eligibility criteria. Six were classified as high risk, one as critical and the other one as uncertain, according to the Robins-I tool. In articles evaluated by the Rob2 tool, ten were classified as serious risk and three as moderate risk. A meta-analysis was also performed. Weighted means were calculated among the studies using the random-effects model and forest plots were generated. Heterogeneity was assessed through the Q test and I2 statistics. It was observed, with moderate evidence, that on a scale of 0 to 10, the pain expectation (effect size 4.75) is higher than that effectively pain generated by the procedure (effect size 1.94). CONCLUSION: Pain expectation was greater than that actually generated by the procedure, being almost non-existent 7 days postoperatively. CLINICAL RELEVANCE: This study may help the clinician to reassure the patient regarding the sensations that could be experienced during and after the installation.

Users' perceptions and preferences towards maxillary removable orthodontic retainers: a crossover randomized clinical trial.

The aim of this study was to assess, correlate, and compare users' perceptions and preference related to maxillary removable retainers. Volunteers were recruited to use four retainer types: conventional wrap-around (CWA), wrap-around with an anterior opening (OWA), "U" wrap-around (UWA), and clear thermoplastic retainer (CT). The main outcomes were the volunteers' perceptions, evaluated with a 100-mm visual analogue scale, and their preferred retainer. The retainers were used for 21 days each (washout intervals of 7 days). Nineteen volunteers (27 ± 4.53 years) were randomly divided into four groups that used the four retainers, but with a different sequence. Perceptions were evaluated immediately after the use of each retainer and the preference at the end of the research. Repeated measures ANOVA and Friedman tests with post-hoc Tukey's test (intergroup comparisons), and Pearson and Spearman analyses (correlations between perceptions) were applied. The WA retainers did not significantly differ among themselves. The CT was rated significantly worse in speech (p ≤ 0.001), discomfort (p < 0.001), and occlusal interference (p < 0.001), and did not significantly differ from the others in esthetics. Users preferred significant more the WA retainers in comparison with the CT retainers. The occlusal interference caused by the CT was positively correlated to other perceptions, such as changes in speech and discomfort. WA retainers presented similar preference and perceptions, but were significantly better than the CT. The CT occlusal coverage appeared to be the primary cause of its rejection.

Users' perceptions and preferences towards maxillary removable orthodontic retainers: a crossover randomized clinical trial

Abstract The aim of this study was to assess, correlate, and compare users' perceptions and preference related to maxillary removable retainers. Volunteers were recruited to use four retainer types: conventional wrap-around (CWA), wrap-around with an anterior opening (OWA), "U" wrap-around (UWA), and clear thermoplastic retainer (CT). The main outcomes were the volunteers' perceptions, evaluated with a 100-mm visual analogue scale, and their preferred retainer. The retainers were used for 21 days each (washout intervals of 7 days). Nineteen volunteers (27 ± 4.53 years) were randomly divided into four groups that used the four retainers, but with a different sequence. Perceptions were evaluated immediately after the use of each retainer and the preference at the end of the research. Repeated measures ANOVA and Friedman tests with post-hoc Tukey's test (intergroup comparisons), and Pearson and Spearman analyses (correlations between perceptions) were applied. The WA retainers did not significantly differ among themselves. The CT was rated significantly worse in speech (p ≤ 0.001), discomfort (p < 0.001), and occlusal interference (p < 0.001), and did not significantly differ from the others in esthetics. Users preferred significant more the WA retainers in comparison with the CT retainers. The occlusal interference caused by the CT was positively correlated to other perceptions, such as changes in speech and discomfort. WA retainers presented similar preference and perceptions, but were significantly better than the CT. The CT occlusal coverage appeared to be the primary cause of its rejection.

Nonsurgical treatment and stability of an adult with a severe anterior open-bite malocclusion.

OBJECTIVES: A skeletal anterior open-bite is a challenging malocclusion for the orthodontist due to the difficulty and instability of correction. Treatment options for the adult patient include extractions, anterior extrusion with intermaxillary elastics, posterior intrusion using skeletal anchorage, occlusal adjustment, and orthognathic surgery. Patient compliance plays a key role in posttreatment stability. The present case report demonstrates the orthodontic treatment of an adult patient who presented with a complex open-bite malocclusion. MATERIALS AND METHODS: Treatment involved the placement of four miniscrews to assist intrusion of maxillary molars by applying posterior vertical maxillary elastics and extrusion of the anterior segments using anterior vertical interarch elastics. RESULTS: Ideal intercuspation was successfully achieved and good stability was maintained during 3 years following treatment. CONCLUSION: The intrusion of the maxillary molars with miniscrews is an interesting option in selected cases of skeletal anterior open bite. The retention protocol should be specific in these cases.

Changes consequent to maxillary molar distalization with the bone-anchored pendulum appliance.

OBJECTIVES: This retrospective study aimed to evaluate the dentoalveolar, skeletal, and soft tissue effects obtained with bone-anchored pendulum appliance in patients with Class II malocclusion. MATERIALS AND METHODS: A total of 18 patients (4 male, 14 female) at a mean pretreatment age of 14.0 years (+1.08) were enrolled in this study. All patients were treated with the bone-anchored pendulum appliance for an average duration of 4.8 months. Only the active distalization period was evaluated with predistalization and postdistalization lateral cephalograms. Skeletal, dentoalveolar, and soft tissue variables were obtained. Based on these variables, the treatment effects were evaluated with dependent t-test. RESULTS: Correction of Class II molar relationship resulted from distal movement of 3.45 mm and tipping of 11.24° of the first maxillary molars. The premolars were distalized accompanying the molars. CONCLUSIONS: The bone-anchored pendulum appliance proved to be an effective method for distalization of maxillary molars in cases that require maximum anchorage, avoiding reciprocal mesial movement of premolars and incisors.

Subjective facial analysis and its correlation with dental relationships.

INTRODUCTION:: Subjective facial analysis is a diagnostic method that provides morphological analysis of the face. Thus, the aim of the present study was to compare the facial and dental diagnoses and investigate their relationship. METHODS:: This sample consisted of 151 children (7 to 13 years old), without previous orthodontic treatment, analyzed by an orthodontist. Standardized extraoral and intraoral photographs were taken for the subjective facial classification according to Facial Pattern classification and occlusal analyses. It has been researched the occurrence of different Facial Patterns, the relationship between Facial Pattern classification in frontal and profile views, the relationship between Facial Patterns and Angle classification, and between anterior open bite and Long Face Pattern. RESULTS:: Facial Pattern I was verified in 64.24% of the children, Pattern II in 21.29%, Pattern III in 6.62%, Long Face Pattern in 5.96% and Short Face Pattern in 1.99%. A substantial strength of agreement of approximately 84% between frontal and profile classification of Facial Pattern was observed (Kappa = 0.69). Agreement between the Angle classification and the Facial Pattern was seen in approximately 63% of the cases (Kappa = 0.27). Long Face Pattern did not present more open bite prevalence. CONCLUSION:: Facial Patterns I and II were the most prevalent in children and the less prevalent was the Short Face Pattern. A significant concordance was observed between profile and frontal subjective facial analysis. There was slight concordance between the Facial Pattern and the sagittal dental relationships. The anterior open bite (AOB) was not significantly prevalent in any Facial Pattern.

Subjective facial analysis and its correlation with dental relationships

ABSTRACT INTRODUCTION: Subjective facial analysis is a diagnostic method that provides morphological analysis of the face. Thus, the aim of the present study was to compare the facial and dental diagnoses and investigate their relationship. METHODS: This sample consisted of 151 children (7 to 13 years old), without previous orthodontic treatment, analyzed by an orthodontist. Standardized extraoral and intraoral photographs were taken for the subjective facial classification according to Facial Pattern classification and occlusal analyses. It has been researched the occurrence of different Facial Patterns, the relationship between Facial Pattern classification in frontal and profile views, the relationship between Facial Patterns and Angle classification, and between anterior open bite and Long Face Pattern. RESULTS: Facial Pattern I was verified in 64.24% of the children, Pattern II in 21.29%, Pattern III in 6.62%, Long Face Pattern in 5.96% and Short Face Pattern in 1.99%. A substantial strength of agreement of approximately 84% between frontal and profile classification of Facial Pattern was observed (Kappa = 0.69). Agreement between the Angle classification and the Facial Pattern was seen in approximately 63% of the cases (Kappa = 0.27). Long Face Pattern did not present more open bite prevalence. CONCLUSION: Facial Patterns I and II were the most prevalent in children and the less prevalent was the Short Face Pattern. A significant concordance was observed between profile and frontal subjective facial analysis. There was slight concordance between the Facial Pattern and the sagittal dental relationships. The anterior open bite (AOB) was not significantly prevalent in any Facial Pattern.

RESUMO INTRODUÇÃO: a análise facial subjetiva é um método diagnóstico que privilegia a avaliação morfológica da face; assim, o principal objetivo do presente trabalho foi comparar os diagnósticos faciais e dentários e investigar a correlação entre eles. MÉTODOS: a amostra consistiu de 151 crianças (7 a 13 anos de idade), sem nenhum tratamento ortodôntico prévio, analisadas por um ortodontista. Foram realizadas fotografias padronizadas extrabucais e intrabucais, para a classificação subjetiva dos Padrões Faciais e das relações dentárias segundo a classificação de Angle. Investigou-se a ocorrência de diferentes tipos de Padrões Faciais, em vistas frontal e de perfil; a relação entre os Padrões Faciais e as relações dentárias de Classe e, também, entre a má oclusão de mordida aberta anterior e o Padrão Face Longa. RESULTADOS: o Padrão Facial I (PF I) esteve presente em 64,24% das crianças; o PF II, em 21,29%; o PF III, em 6,62%; o PF Face Longa, em 5,96% e o PF Face Curta, em 1,99%. Observou-se concordância substancial entre a avaliação do PF na vista frontal e na de perfil, igual a 84% (Kappa = 0,69). Houve concordância entre a avaliação da relação dentária de Classe e do PF em 63% da amostra (Kappa = 0,27). O PF Face Longa não demonstrou maior prevalência da má oclusão de mordida aberta. CONCLUSÃO: os Padrões Faciais I e II foram os mais prevalentes em crianças, enquanto o menos prevalente foi o Padrão Face Curta. Verificou-se concordância significativa entre as análises faciais frontal e de perfil. Existe uma ligeira concordância entre o Padrão Facial e a relação sagital dentária. A mordida aberta anterior não se apresentou mais prevalente em nenhum tipo de Padrão Facial.

Could formaldehyde induce mutagenic and cytotoxic effects in buccal epithelial cells during anatomy classes?

BACKGROUND: Due to increased formaldehyde exposure, carcinogenic to humans, several researches have been studying the potential toxicity and the safe levels for human beings. The aim of this study was to investigate mutagenicity and cytotoxicity in buccal epithelial exfoliated cells (BEC) of students subjected to formaldehyde (FA) during anatomy classes. MATERIAL AND METHODS: BEC were collected periodically from 17 volunteers of undergraduate programs, who had participated in practical anatomy classes, before and after FA exposure. Cells were stained according to Feulgen method and then micronucleus test was applied. A total of 1,500 cells were assessed per individual in this study for the micronucleus frequency and other parameters of cytotoxicity. RESULTS: There was statistically significant increase in number of micronucleated BEC after FA exposure (after 1 month p=.034 and after 3.5 months p=.017). However, FA exposure caused no significant increase in other nuclear alterations closely related to cytotoxicity (p≥.05). CONCLUSIONS: FA induced mutagenicity during anatomy classes. Cell death increased, but it was not statistically significant. Efforts have to be made to improve air quality and reduce exposures during anatomy classes

Evaluation of secondary alveolar bone grafting outcomes performed after canine eruption in complete unilateral cleft lip and palate.

OBJECTIVES: Evaluate the results of secondary alveolar bone grafting (SABG) in patients with complete unilateral cleft lip and palate (UCLP), operated after permanent canine eruption (CE). MATERIALS AND METHODS: Seventy-four periapical radiographs from patients with complete UCLP (mean age 14 years) submitted to SABG were retrospectively analyzed for the amount of bone in the cleft site through the Bergland and Chelsea scales. RESULTS: Of the cases, 47.3 % was classified as Bergland type I and Chelsea type A, 35.2 % as type II/C, 6.7 % as type III/D, and 10.8 % as type IV/failure. When the canine was moved into the grafted area, the success rate (type I/A) was 56.8 %; for cases in which the space was maintained for an implant or prosthetic finishing, the index was 45.8 %; however, this difference was not statistically significant. CONCLUSION: Even in advanced ages, after permanent canine eruption, SABG can be considered a highly successful procedure. CLINICAL RELEVANCE: This research shows good results of secondary alveolar bone grafting performed in patients with unilateral complete cleft lip and palate, even when it was performed after eruption of the permanent canine in the cleft area.

Nuclear alterations in nasal mucosa epithelial cells of students exposed to formaldehyde / Alteraciones en los núcleos de las células epiteliales de la mucosa nasal de los estudiantes expuestos a formaldehído

INTRODUCTION: Formaldehyde is a compound with a wide range and is commonly used in anatomy and pathology laboratories. At room temperature is quickly volatilized to a pungent and suffocating gas and its inhalation has been correlated to nuclear alterations in different tissues. We aimed to investigate whether exposure to this compound was correlated with the appearance of cytotoxic and genotoxic features in the nasal epithelial cells of students enrolled in a human anatomy course. MATERIAL AND METHODS: This prospective study collected periodically nasal cells from mucosa of 17 volunteers from two different undergraduate programs with different workloads of practical lessons in an anatomy laboratory, 30 and 90 hours per semester. Cells were staining according to Feulgen method and nuclear morphology was analyzed to detect possible damage. Dunn's post hoc test was used in the statistical analysis. Pearson's correlation was performed for gender, age and questionnaire responses. RESULTS: Epithelial cells showed indicators of cytotoxicity and mutagenicity. Students with a more extensive workload in anatomy laboratory displayed a more severe profile with an increase in karyorrhexis (p 0.05). CONCLUSION: Individuals exposed for short periods of time to formaldehyde are subject to the toxic action of this gas. Karyorrhexis was the most frequently observed cytotoxic feature and micronucleus showed an increase between the first time point. The patterns observed between the student's groups suggest a negative effect due to exposure time

INTRODUCCIÓN: El formaldehído es un compuesto con una amplia variedad y se utiliza comúnmente en los laboratorios de anatomía y patología. En la temperatura ambiente se volatiliza rápidamente en un gas acre sofocante. Su inhalación se ha correlacionado con la aparición de alteraciones nucleares en diferentes tejidos. El objetivo fue investigar si la exposición a este compuesto podría estar relacionado con la aparición de aspectos citotóxicos y genotóxicos en las células epiteliales nasales de los estudiantes del curso de anatomía humana. MATERIAL Y MÉTODOS: En este estudio las células nasales proclives se recogieron periódicamente de la mucosa de los 17 voluntarios de las carreras universitarias con diferentes cargas de clases prácticas en el laboratorio de anatomía, 30 y 90 horas semestrales. Las células fueron teñidas por el método de Feulgen y la morfología nuclear fue evaluada para la detección de posibles daños. Prueba post hoc de Dunn fue utilizada para el análisis estadístico. Correlación de Pearson fue realizada con los datos de sexo, edad y las respuestas del cuestionario. RESULTADOS: Las células epiteliales mostraron indicadores de citotoxicidad, mutagenicidad. Los estudiantes con una carga de trabajo más extensa en el laboratorio de anatomía mostraron perfil más grave con el aumento de cariorrexis (p 0,05). CONCLUSIÓN: Individuos expuestos durante cortos períodos de tiempo a formaldehído están sujetos a la acción tóxica de gas. Cariorrexis fue la característica citotóxica observada con mayor frecuencia y micronúcleos mostraron un aumento entre el primer punto de tiempo. Los diferentes patrones de daños observados entre los grupos de estudiantes sugieren que el efecto negativo de gas puede está relacionado con el tiempo de exposición

Alterações produzidas na fala por contenções superiores ortodônticas - ensaio clínico randomizado prospectivo / Alterations produced in speech due to upper orthodontic restraints - prospective randomizes clinical trial

Objetivo: Avaliar e comparar a influência das diferentes contenções ortodônticas superiores na fala e as percepções dos voluntários às diferentes condições provocadas pela sua utilização. Correlacionar as percepções entre si e com as dimensões do arco superior. Material e Métodos: Selecionou-se 21 (n) voluntários para utilizar 4 tipos de contenções removíveis superiores (Placa wrap-around convencional, em U e com orifício anterior e contenção termoplástica transparente-CTT) por 21 dias cada, com intervalos de 7 dias sem utilização entre elas. Durante a pesquisa, alguns voluntários desistiram ou não compareceram às avaliações, sendo excluídos. As percepções dos pacientes aos aparelhos foram avaliadas com a Escala Visual Analógica de 100 mm (n final=19), e correlacionou-se estas entre si. A avaliação da fala (n final=18) foi realizada em gravações de trechos vocais realizadas antes e imediatamente após a instalação das 4 contenções, assim como após 21 dias de uso destas. Para isto empregou-se a Análise Perceptiva Auditiva da fala e a Análise Acústica da frequência dos formantes F1 e F2 das vogais. Aplicou-se a ANOVA para dados repetidos e teste de Friedman com post hoc de Tukey, além das Correlações de Pearson e de Spearman para as avaliações. O nível de significância estatística estabelecido foi de 5%. Resultados: Os variados desenhos das contenções wrap-around não diferiram de forma significante em nenhuma das percepções e a CTT recebeu notas estatisticamente piores em todos os quesitos, com exceção da estética onde não diferiu estatisticamente das demais. Correlações positivas importantes foram encontradas entre alterações na fala e desconforto em todos os aparelhos. A interferência oclusal na CTT correlacionou-se muito positivamente a outras percepções, como alterações na fala e desconforto. Na avaliação perceptivo-auditiva, as alterações na fala aumentaram significantemente no momento imediato após a instalação do wrap-around com orifício e da CTT, e continuaram significantemente elevadas após 3 semanas. A frequência dos formantes das vogais foi prejudicada no momento inicial da instalação e as Alterações mantiveram-se presentes no wrap-around convencional, em U e na CTT após 3 semanas. Conclusões: A CTT prejudicou mais a fala que os wrap-around. Entre estes, os wrap-around convencional e em U interferiram menos na fala. O período de 3 semanas de uso dos aparelhos não foi totalmente suficiente para a readaptação da fala. A CTT foi pior classificada que as placas wrap-around em todas percepções avaliadas, exceto na estética, onde não diferiram significantemente. A cobertura oclusal da CTT pareceu ser a causadora da sua reprovação e das maiores alterações à fala nesta contenção. As dimensões do arco superior pouco influenciaram as percepções. Considerando as alterações na fala e as percepções dos pacientes, as contenções wrap-around apresentaram melhor desempenho e devem ser a primeira escolha quando a opção de contenção do arco superior for um aparelho removível.(AU)

Objective: To evaluate and compare the influence of different upper removable orthodontic retainers on speech and volunteers' perceptions to different conditions caused by their use. To correlate perceptions with each other and with upper arch dimensions. Material and Methods: 21 (n) volunteers were selected to use four types of upper removable retainers (conventional wrap-around, horseshoe-shaped wrap-around, wrap-around with an anterior "hole" and transparent thermoplastic retainer - TTR) for 21 days each, with intervals of 7 days without use between them. During the search, some volunteers dropped out or did not attend the evaluations and were excluded. Patients perceptions (final n=19) were evaluated with a visual analogue scale of 100 mm, and these were correlated with each other. Speech evaluation (final n=18) was performed in vocal excerpts recordings made before, immediately after and 21 days after the installation of each appliance, with Perceptual Auditory Analysis Auditory and Acoustic Analysis of formant frequencies F1 and F2 of the vowels. ANOVA for repeated measures and Friedman test with post hoc Tukey, in addition to Pearson and Spearman correlation for the evaluations were applied for statistics evaluation. The level of statistical significance was set at 5%. Results: Different designs of wrap-around retainers did not differ significantly in any of the perceptions and TTR received significantly worse grades in all aspects, except for esthetics, which did not statistically differ from the others. Significant positive correlations were observed between changes in speech and discomfort on all appliances. Occlusal interference in TTR was very positively correlated to other perceptions, such as changes in speech and discomfort. Speech changes, evaluated by Perceptual Auditory Analysis, increased immediately after conventional wraparound and TTR installation, and reduced after 3 weeks of use, but not back to normal levels observed without device. However, this increase was statistically significant only for the conventional wrap-around and TTR, remaining significant high after 3 weeks. Formant frequencies of vowels were altered at initial time and the changes remained present in conventional, horseshoe-shaped and TTR appliances after 3 weeks. Conclusions: TTR was more harmful to speech than the wrap-around appliances. Among these, conventional and horseshoe-shaped has interfered less in speech. The 3-week period with retainers was not fully sufficient for speech adaptation. TTR was worse classified than the wrap-around retainers in all evaluated perceptions, except in esthetics, which did not differ significantly. Occlusal coverage of TTR seems to be the cause of its rejection and its major changes to speech. Upper arch dimensions little influence volunteers perceptions. Considering speech changes and volunteers perceptions, the wrap-around retainers had better performance and should be the first choice when retainer option is a removable device in the upper arch.(AU)

Mutagenicity and cytotoxicity in patients submitted to ionizing radiation.

OBJECTIVES: To evaluate and compare mutagenicity (micronucleus) and cytotoxicity (karyorrhexis, pyknosis, and karyolysis) in exfoliated buccal mucosa cells of children following cone beam computed tomography (CBCT) or conventional radiograph exposure necessary for orthodontic planning. MATERIALS AND METHODS: A total of 49 healthy children were submitted to CBCT or a conventional orthodontic radiographic protocol; they were divided into two groups based on exam: CBCT (n  =  24) and Radiographic Set (n  =  25) groups. The micronucleus test in the exfoliated buccal mucosa cells was applied. RESULTS: There was not a statistically significant difference (P > .05) found between the number of micronucleated buccal mucosa cells (MNC) before and after exposure to radiation in either group, showing that neither group experienced a mutagenic effect. However, radiation did cause other nuclear alterations closely related to cytotoxicity, including karyorrhexis, pyknosis, and karyolysis, in both groups (P < .05). The CBCT group presented a greater increase in cell death than was noted in the Radiographic Set group (P < .044). CONCLUSION: According to the micronucleus test, mutagenicity was not induced by the CBCT or the conventional radiographs, but cytotoxicity was verified after these exams, especially after CBCT. That might have happened once the CBCT group received a greater radiation dose than the Radiographic Set group as a result of the protocols used in orthodontic planning for this study.

Cone-beam computed tomography and radiographs in dentistry: aspects related to radiation dose.

Introduction. The aim of this study was to discuss the radiation doses associated with plain radiographs, cone-beam computed tomography (CBCT), and conventional computed tomography (CT) in dentistry, with a special focus on orthodontics. Methods. A systematic search for articles was realized by MEDLINE from 1997-March 2011. Results. Twenty-seven articles met the established criteria. The data of these papers were grouped in a table and discussed. Conclusions. Increases in kV, mA, exposure time, and field of view (FOV) increase the radiation dose. The dose for CT is greater than other modalities. When the full-mouth series (FMX) is performed with round collimation, the orthodontic radiographs transmit higher dose than most of the large FOV CBCT, but it can be reduced if used rectangular collimation, showing lower effective dose than large FOV CBCT. Despite the image quality, the CBCT does not replace the FMX. In addition to the radiation dose, image quality and diagnostic needs should be strongly taken into account.

Cytogenetic biomonitoring in children submitting to a complete set of radiographs for orthodontic planning.

OBJECTIVES: To evaluate the DNA damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated buccal mucosa cells from children undergoing orthodontic radiographs. MATERIALS AND METHODS: A total of 25 healthy children undergoing orthodontic therapy partook in a complete set of orthodontic radiographs (lateral cephalographic, posteroanterior cephalographic, panoramic, full periapical exam, and bitewing). The micronucleus test in the buccal exfoliated cells was applied. The paired-samples t-test and the Wilcoxon test were used to compare the frequencies of alterations before and after X-ray exposure. RESULTS: We found no statistically significant differences (P > .05) between micronucleated buccal mucosa cells before and after exposure to radiation. However, radiation did cause other nuclear alterations closely related to cytotoxicity (P  =  .007). CONCLUSION: According to the micronucleus test, the complete set of radiographs requested in the orthodontic planning may not be a factor that induces chromosomal damage, but it is able to promote cytotoxicity.

Facial profile evaluation of isolated Pierre Robin sequence.

OBJECTIVE: To evaluate numerically the facial profile of children with isolated Pierre Robin sequence (PRS) and to compare them with a control group that has no pathologies and exhibits regular and balanced facial growth, with no skeletal alterations. PATIENTS: Eighty-three children aged 5 to 10 years (PRS group, n  =  60; control group, n  =  23) were selected. SETTING: Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC-USP). Children from the control group were taken from the program of Interceptive Orthodontics at HRAC-USP. DESIGN: Angular and ratio analyses of the facial profiles in both groups were realized through digital photographs. The PRS group was subdivided into two groups--complete and incomplete--according to the sagittal extension of the cleft palate, to investigate the possible influence of cleft extension on the face. RESULTS: The facial convexity angle and the facial inferior third angle were considerably higher in the PRS groups than in the control group and were not significantly different between PRS groups. Nasolabial angle did not differ between groups. CONCLUSION: The facial profile was more convex in individuals with PRS than in those with regular facial growth and with no pathology. The mandible was responsible for the convexity of the profile in PRS because of its lack off anterior projection. An important relationship between the extension of the cleft palate and alterations in facial profile in PRS was not observed.