Mini-implants: microbiological evaluation, proinflammatory cytokines, bacterial endotoxin and osteoclastogenesis marker proteins quantification in cases of success and failure

• Grant number: 11/23822-0
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2012
• End date: March 31, 2014
• Field of knowledge: Health Sciences - Dentistry - Orthodontics
• Principal Investigator: Paulo Nelson Filho
• Grantee: Paulo Nelson Filho
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated researchers: Carlos Arterio Sorgi ; Lúcia Helena Faccioli ; Mírian Aiko Nakane Matsumoto ; Sandra Yasuyo Fukada Alves

Abstract

Mini-implants have been widely used in orthodontics as anchorage devices, but their early loss may occur during the treatment. Several aspects have been investigated in order to identify the possible causes of failure, but they are not yet completely elucidated. Therefore, the purposes of this in vivo study will be: 1) to evaluate the contamination of stable and unstable/loose orthodontic mini-implants by 16 Gram-negative periodontopathogenic bacterial species using whole genomic DNA probes by the Checkerboard DNA-DNA Hybridization (CDDH) biomolecular technique; 2) to quantify the bacterial endotoxin present in the mini-implants by the Limulus Amebocyte Lysate (LAL) assay; and 3) to quantify the proinflammatory cytokines IL-1±, IL-6, IL-17 and TNF-± and the osteoclastogenesis marker proteins (RANK, RANL and OPG) by real-time polymerase chain reaction (RT-PCR). Patients of both sexes (15 to 25 years old) under orthodontic treatment with corrective appliance and mini-implants will be selected to obtain 15 stable mini-implants (success) and unstable/loose 15 mini-implants (failure). The mean time of permanence in the mouth will be 1 year for stable mini-implants and 2 months for unstable/loose mini-implants. The mini-implants (1.6 mm diameter x 7.0-9.0 mm long) of the commercial brand 'Neodent' (Curitiba, PR, Brazil) will be placed in the maxilla and/or mandible. All mini-implants will be placed and removed by the same surgeon. At the moment of removal, the mini-implants will be collected and processed for microbial detection by CDDH, quantification of bacterial endotoxina by the LAL assay, and quantification of proinflammatory cytokines and osteoclastogenesis markers by RT-PCR. The results from detection of Gram-negative periodontopathogenic microorganisms and quantification of endotoxin will be subjected to nonparametric statistical analysis using the Mann-Whitney test, Kruskal-Wallis test and Dunn's post-test. The results from detection of proinflammatory cytokines and the osteoclastogenesis marker proteins be tabulated and subjected to analysis of variance, using SAS and GraphPad Prism softwares. A significance level of 5% will be adopted for all analyses. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MARCELA CRISTINA DAMIÃO ANDRUCIOLI; MÍRIAN AIKO NAKANE MATSUMOTO; SANDRA YASUYO FUKADA; MARIA CONCEIÇÃO PEREIRA SARAIVA; ANA ZILDA NAZAR BERGAMO; FÁBIO LOURENÇO ROMANO; RAQUEL ASSED BEZERRA DA SILVA; LEA ASSED BEZERRA DA SILVA; PAULO NELSON-FILHO. Quantification of pro-inflammatory cytokines and osteoclastogenesis markers in successful and failed orthodontic mini-implants. Journal of Applied Oral Science, v. 27, 2019-10-07. (11/23822-0)

DAMIAO ANDRUCIOLI, MARCELA CRISTINA; NAKANE MATSUMOTO, MIRIAN AIKO; PEREIRA SARAIVA, MARIA CONCEICAO; FERES, MAGDA; DE FIGUEIREDO, LUCIENE CRISTINA; SORGI, CARLOS ARTERIO; FACCIOLI, LUCIA HELENA; BEZERRA DA SILVA, RAQUEL ASSED; BEZERRA DA SILVA, LEA ASSED; NELSON-FILHO, PAULO. Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin. Journal of Applied Oral Science, v. 26, 2018. (11/23822-0)