Calcitonin as a Pharmacological Anchorage in Orthodontics

Objective: This study aimed to evaluate the effects of salmon calcitonin administration as a pharmacological anchoring agent in orthodontics and to determine the influence of locally applied calcitonin on serum calcium levels. The secondary aim was to observe the response of dental and periodontal tissues using light microscopy. Methods: Fourteen healthy male adult Wistar rats with an average weight of 250 g had their teeth moved, seven of which received a local injection of salmon calcitonin in the furcation region of the left upper first molar. Concurrently, the remaining seven were used as controls. In the control group, saline solution was injected in the bifurcation region of tooth 26 to subject these animals to the same stress level as those of the experimental group. After 14 days, a 6 mm diameter orthodontic elastic band was inserted between teeth 26 and 27 in all animals to induce the movement of these teeth. The rats were anaesthetised and exsanguinated on day 21. In both groups, tooth movement and serum calcium levels were measured. The jaws were dissected with straight scissors, and tissue blocks containing gingiva, bone and teeth were identified, fixed and demineralised. Then, the pieces were cut into semi?serial slices, stained with hematoxylin, eosin, and Mallory’s trichrome, and analysed under an Axiophot light microscope. Results: There was significantly less tooth movement in the experimental group ( ±X DP ; 0,150 mm ± 0,037) than in the control group (0,236 mm ± 0,044; P = 0,003), while there was no significant difference in serum calcium levels between the two groups (control ±X DP ; 9,53 mg/dl ± 1,53; experimental 10,81 mg/dl ± 1,47; P = 0,15). Conclusion: While calcitonin did not completely inhibit osteoclast activity, it promoted orthodontic anchorage, apparently, by local action.

Obstructive sleep apnea in adults

ABSTRACT Introduction: Obstructive Sleep Apnea and Hypopnea Syndrome (OSAS) is a highly prevalent disease with serious consequences for the patients' lives. The treatment of the condition is mandatory for the improvement of the quality of life, as well as the life expectancy of the affected individuals. The most frequent treatments provided by dentistry are mandibular advancement devices (MAD) and orthognathic surgery with maxillomandibular advancement (MMA). This is possibly the only treatment option which offers high probability of cure. Objective: The present article provides a narrative review of OSAS from the perspective of 25 years of OSAS treatment clinical experience. Conclusion: MADs are a solid treatment option for primary snoring and mild or moderate OSAS. Patients with severe apnea who are non-adherent to CPAP may also be treated with MADs. Maxillomandibular advancement surgery is a safe and very effective treatment option to OSAS.

RESUMO Introdução: a Síndrome da Apneia e Hipopneia Obstrutiva do Sono (SAOS) é uma doença muito prevalente e que traz importantes consequências para a vida dos seus portadores. O tratamento da condição é relevante para a melhora do bem-estar geral e da expectativa de vida dos afetados. Os tratamentos odontológicos mais frequentes para a SAOS são os dispositivos de avanço mandibular (DAMs) e a cirurgia ortognática de avanço maxilomandibular (AMM) - essa última, possivelmente, é a única opção de tratamento com alta probabilidade de cura do problema. Objetivo: o presente artigo faz uma revisão narrativa da SAOS sob a perspectiva de 25 anos de experiência clínica no tratamento da doença. Conclusão: os DAMs são uma sólida opção de tratamento para o ronco primário e apneias leves ou moderadas. Apneias graves, em pacientes que não se adaptam ou se recusam a usar o CPAP, também podem ser tratadas com os DAMs. A cirurgia ortognática de AMM é uma alternativa segura e muito eficaz de solução da SAOS.

Writing scientific manuscripts: most common mistakes

ABSTRACT I have had the privilege of serving as editor-in-chief for 11 years of two scientific journals: The Dental Press Journal of Orthodontics and the Journal of the World Federation of Orthodontists. I had the opportunity to read and correct thousands of manuscripts. This experience was greatly enriching, because reading a text professionally completely differs from the perspective of readers in general. The routine practice of correcting manuscripts has made me realize that some errors recur frequently. To help authors to improve their manuscripts before submission, these problems are discussed here in the order that they appear in conventional manuscript sections.

RESUMO Ao longo dos 11 anos em que atuei como editor-chefe de revistas científicas (Dental Press Journal of Orthodontics e Journal of the World Federation of Orthodontists), tive a oportunidade de ler e corrigir milhares de manuscritos - manuscrito, no jargão editorial, é o trabalho submetido para publicação ainda não editado e publicado. Essa experiência foi muito enriquecedora, pois a leitura profissional de um texto difere totalmente daquela realizada pelos leitores em geral. O lidar corriqueiro com as correções de manuscritos me fez perceber que alguns erros são muito recorrentes. Eles serão discutidos na ordem das seções apresentadas nos trabalhos, com o objetivo de ajudar os autores a melhorar seus manuscritos antes da submissão.

Caries risk assessment in schoolchildren - a form based on Cariogram® software

Identifying caries risk factors is an important measure which contributes to best understanding of the cariogenic profile of the patient. The Cariogram® software provides this analysis, and protocols simplifying the method were suggested. Objectives: The aim of this study was to determine whether a newly developed Caries Risk Assessment (CRA) form based on the Cariogram® software could classify schoolchildren according to their caries risk and to evaluate relationships between caries risk and the variables in the form. Material and Methods: 150 schoolchildren aged 5 to 7 years old were included in this survey. Caries prevalence was obtained according to International Caries Detection and Assessment System (ICDAS) II. Information for filling in the form based on Cariogram® was collected clinically and from questionnaires sent to parents. Linear regression and a forward stepwise multiple regression model were applied to correlate the variables included in the form with the caries risk. Results: Caries prevalence, in primary dentition, including enamel and dentine carious lesions was 98.6%, and 77.3% when only dentine lesions were considered. Eighty-six percent of the children were classified as at moderate caries risk. The forward stepwise multiple regression model result was significant (R2=0.904; p<0.00001), showing that the most significant factors influencing caries risk were caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources. Conclusion: The use of the form based on the Cariogram® software enabled classification of the schoolchildren at low, moderate and high caries risk. Caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources are the variables that were shown to be highly correlated with caries risk. .

How sample size influences research outcomes

Sample size calculation is part of the early stages of conducting an epidemiological, clinical or lab study. In preparing a scientific paper, there are ethical and methodological indications for its use. Two investigations conducted with the same methodology and achieving equivalent results, but different only in terms of sample size, may point the researcher in different directions when it comes to making clinical decisions. Therefore, ideally, samples should not be small and, contrary to what one might think, should not be excessive. The aim of this paper is to discuss in clinical language the main implications of the sample size when interpreting a study.

O cálculo amostral faz parte dos estágios iniciais de realização de um estudo epidemiológico, clínico ou laboratorial. Há indicações éticas e metodológicas para o seu emprego na elaboração de um trabalho científico. Duas pesquisas, realizadas com a mesma metodologia obtendo resultados equivalentes, e que diferem apenas no tamanho da amostra, podem apontar para diferentes direções no processo de tomada de decisão clínica. Portanto, as amostras estudadas idealmente não devem ser pequenas e, ao contrário do que pode-se pensar, não devem ser excessivas. O objetivo desse artigo é discutir, numa linguagem clínica, as principais implicações do tamanho das amostras na interpretação de um estudo.

Analysis of Factors Associated with Orthodontic Microscrew Failure

The objective of this study was to examine whether factors such as insertion site, patient's facial pattern, microscrew features, type of tooth movement desired, level of experience handling orthodontic microscrews and operator expertise were associated with failure of microscrews. After the approval of an ethics committee, 166 patients of one practice signed an informed consent and received 293 microscrews randomly distributed by 3 operators with different levels of practical experience and expertise in handling microscrews. The microscrews were observed in a period of 365 days or as long as orthodontic forces had to be applied and independent variables were recorded. Analysis by the chi-square test did not produce enough evidence as to allow the assertion that there was an association between the variable "failure" and the variables "maxilla" (p=0.4775), "face" (p=0.1081), "facial pattern" (p=0.7522), "microscrew length" (p=0.9113), "desired movement" (p=0.0584), and "operator" (p=0.5785). The variable "insertion side" was significantly associated with "failure" (p=0.0022). In a 365-day survival analysis, the Log Rank test yielded a p-value of 0.00178 for the curve of variable "insertion side," and showed no significant differences for other variables. With a total success rate of 87.38%, the only variable found to be significant was "insertion side" (p=0.0022), with 3.088 more likelihood of a microscrew failing if placed on the left side than on the right side. The procedure of inserting microscrews involved a rapid learning curve for an inexperienced operator, which justifies their placement by orthodontists.

O objetivo deste estudo foi examinar se fatores como sítio de inserção, padrão facial do paciente, características do microparafuso, tipo de movimento dental desejado, nível de experiência com microparafusos e expertise do operador têm associação com o insucesso de microparafusos. Após a aprovação em um comitê de ética, 166 pacientes de uma clínica assinaram um consentimento informado e receberam 293 microparafusos aleatoriamente distribuídos entre 3 operadores com diferentes níveis de experiência prática e expertise no manuseio de microparafusos. Os microparafusos foram observados por um período de 365 dias ou pelo tempo necessário de aplicação de forças ortodônticas e as variáveis independentes foram registradas. Análise do teste de qui-quadrado não produziu evidência suficiente para afirmar que existe associação entre a variável "insucesso" e as variáveis "maxila" (p=0,4775), "face" (p=0,1081), "padrão facial" (p=0,7522), "comprimento do microparafuso" (p=0,9113), "movimento desejado" (p=0,0584), e "operator" (p=0,5785). A variável "lado de inserção" foi significantemente associada a "insucesso" (p=0,0022). Em uma análise de sobrevivência de 365 dias, o teste Log Rank resultou em um p-valor de 0,00178 para a curva da variável "lado de inserção" e não mostrou evidência suficiente para as outras variáveis. Com um sucesso total de 87,38%, a única variável significante encontrada foi "lado de inserção" (p=0,0022), com uma chance 3,088 vezes maior de se perder o microparafuso instalado do lado esquerdo do que do lado direito. O procedimento de inserção dos microparafusos envolveu uma rápida curva de aprendizado para um operador inexperiente, o que justifica sua instalação pelos ortodontistas.