Genetic polymorphism in RANK is associated with mandibular size.

OBJECTIVE: The aim of this study was to evaluate the association between genetic polymorphisms in RANK, RANKL and OPG with maxillary and mandibular dimensions in humans. DESIGN: DNA extracted from saliva and the rs3826620, rs9594738 and rs2073618 polymorphisms in RANK, RANKL and OPG, respectively, were analysed by real-time PCR. Four linear measurements (Co-Gn, GoPg, Co-Go and PTM-A) from lateral cephalograms were examined for the evaluation of craniofacial measurements. ANOVA testing and a multivariate linear regression analysis, adjusted for age and gender, were used for statistical analysis, with an alpha of 5%. Hardy-Weinberg equilibrium was also evaluated using the chi-square test within each polymorphism. SETTING: School of Dentistry of Ribeirão Preto, University of São Paulo. PARTICIPANTS: A total of 100 unrelated non-syndromic Brazilian Caucasian subjects were included in this study. RESULTS: The polymorphism in RANK was associated with a higher Go-Pg measurement (p = .039). In the multivariate analysis, adjusted for age and gender, the polymorphism in RANK was associated with Go-Pg (p = .017) and Co-Gn (p = .043). CONCLUSION: The polymorphism rs3826620 in RANK is associated with the mandibular size.

Relationship between tooth loss, nutritional status and consumption of macro and micronutrients in elderly people from southern Brazil

Maintaining a functional natural dentition plays an important role in keeping a satisfactory nutritional status. The aim of this study was to evaluate the relationship between oral health conditions determined by the presence of edentulism and the number of missing teeth, nutritional status and consumption of nutrients by the elderly. This cross-sectional study comprised 494 independent elderly of both genders, over 60 years of age, registered at the Brazilian public health service in Londrina, southern Brazil. The data collection included: oral examinations; anthropometric measurements by calculating the Body Mass Index (BMI); analysis of food consumption based on a multiple pass 24-hour dietary recall and a food intake frequency questionnaire; and structured interviews to obtain sociodemographic information. Multiple linear regression, the Fisher's Exact test, chi-square and Mann-Whitney tests, were applied at a 5% significance level. The prevalence of edentulism was 47.3%; this predominated in females, age group from 65 to 74 years, low education level and low/medium economic classification. A larger numberof underweight and fewer number of overweight elderly were recorded among the edentulous versus dentate participants (< 0.0001). Significantly lower consumption of several nutrients, as well as fruit, was recorded among the edentulous group. In particular, carbohydrates, vitamins (B1, B9 and C), and the majority of the minerals studied were associated with a larger number of missing teeth. In conclusion, tooth loss was associated with the food consumption pattern of some macro-and micronutrients and the nutritional status of the Brazilian elderly.

Association between P561T polymorphism in growth hormone receptor gene and mandibular prognathism: systematic review and metaanalysis

Objective: Through a systematic review and meta-analysis, the aim this study was evaluating the association between the P561T polymorphism in GHR (rs6184) with skeletal Class III malocclusion in different populations. Methods: A broad search for studies was conducted using the databases: PubMed, Web of Science, Scopus, Cochrane, Google Scholar and Open Grey until December 2018. The study design according to PECOS was: P-Orthodontic patients; E- polymorphism P561T in GHR; C- absence of polymorphism P561T in GHR; O- linear dimension alterations in maxilla and mandibular measurements; S- Cross-sectional studies. The selected studies were qualified by 10-point scoring sheet methodological quality. The subgroups evaluation was performd according to the linear measurements evaluated in two or more studies, as follows: body height, N-S, A'-PTM', Gn-Go, Pog'-Go, and Co-Go.A fixed effect model was used and the mean differences were performed using the inverse-variance meta-analysis. The I2 (95%) was used to measure statistical heterogeneity between studies, where I2 values of 25%, 50%, and 75% signified low, medium, and high heterogeneity, respectively. Results: The initial search identified 146 studies. After excluding duplicate abstracts, 138 were selected. Seven studies were included in the systematic review. Only one study was classified as having low methodological quality. Three studies were included in the meta-analysis. The meta-analysis demonstrated an association between the Co-Go linear measure and CC genotype (p<0.0001), with a mean difference and confidence interval of 3.79 [2.06, 5.52]. CC was associated with greater mandibular height. Conclusion: The polymorphism P561T in GHR is associated with Co-Go measurement in Asians, with low level of evidence.

Objetivo: Por meio de uma revisão sistemática e meta-análise, o objetivo deste estudo foi avaliar a associação entre o polimorfismo P561T em GHR (rs6184) com a maloclusão de Classe III esquelética em diferentes populações. Métodos: Uma ampla pesquisa de estudos foi realizada utilizando os bancos de dados PubMed, Web of Science, Scopus, Cochrane, Google Scholar e Open Grey até dezembro de 2018. O desenho do estudo de acordo com o PECOS foi: P-Pacientes ortodônticos; Polimorfismo P561T em GHR; Causência de polimorfismo P561T em GHR ; O-alterações na dimensão linear das medidas maxilares e mandibulares; S- Estudos transversais. Os estudos selecionados foram qualificados pela qualidade metodológica em uma escala de 10 pontos. A avaliação emsubgrupos. O subgrupo foi realizada de acordo com as medidas lineares avaliadas em dois ou mais estudos, como a seguir: altura corporal, N-S, A'-PTM ', Gn-Go, Pog'-Go. Foi utilizado o modelo de efeito fixo e as diferenças médias foram realizada usando a metanálise de variância inversa. O I2 (95%) foi utilizado para medir heterogeneidade estatística entre estudos, em que valores de I2 de 25%, 50% e 75% significaram baixa, média e alta heterogeneidade, respectivamente. Resultados: A pesquisa inicial identificou 146 estudos. Após excluir resumos duplicados, 138 foram selecionados. Sete estudos foram incluídos na revisão sistemática. Apenas 1 estudo foi classificado como de baixa qualidade metodológica. Três estudos foram incluídos na meta-análise. A metaanálise demonstrou uma associação entre a medida linear Co-Go e o genótipo CC (p<0,0001), com diferença média e intervalo de confiança de 3,79 [2,06; 5,52]. CC foi associado com maior altura mandibular. Conclusão: O polimorfismo P561T em GHR está associado à medida Co-Go em asiáticos, com baixo nível de evidência.