Influence of repeated screw tightening on bacterial leakage along the implant-abutment interface

Autor(es)

do Nascimento, Cassio ^[1] ; Pedrazzi, Vinicius ^[1] ; Miani, Paola Kirsten ^[1] ; Moreira, Larissa Daher ^[1] ; de Albuquerque Junior, Rubens Ferreira ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Dent Mat & Prosthodont, Fac Dent Ribeira Preto, BR-14040904 Sao Paulo - Brazil

^[2] McGill Univ, Fac Dent, Quebec City, PQ - Canada

• Tipo de documento: Artigo Científico
• Fonte: Clinical Oral Implants Research; v. 20, n. 12, p. 1394-1397, DEC 2009.
• Citações Web of Science: 30

Resumo

Objectives Bacterial penetration along the implant-abutment interface as a consequence of abutment screw loosening has been reported in a number of recent studies. The aim of this in vitro study was to investigate the influence of repeated tightening of the abutment screw on leakage of Streptococcus mutans along the interface between implants and pre-machined abutments. Materials and methods Twenty pre-machined abutments with a plastic sleeve were used. The abutment screws were tightened to 32 N cm in group 1 (n=10 - control) and to 32 N cm, loosened and re-tightened with the same torque twice in group 2 (n=10). The assemblies were completely immersed in 5 ml of Tryptic Soy Broth medium inoculated with S. mutans and incubated for 14 days. After this period, contamination of the implant internal threaded chamber was evaluated using the DNA Checkerboard method. Results Microorganisms were found on the internal surfaces of both groups evaluated. However, bacterial counts in group 2 were significantly higher than that in the control group (P < 0.05). Conclusion These results suggest that bacterial leakage between implants and abutments occurs even under unloaded conditions and at a higher intensity when the abutment screw is tightened and loosened repeatedly. To cite this article:do Nascimento C, Pedrazzi V, Kirsten Miani P, Daher Moreira L, de Albuquerque Junior RF. Influence of repeated screw tightening on bacterial leakage along the implant-abutment interface.Clin. Oral Impl. Res. 20, 2009; 1394-1397.doi: 10.1111/j.1600-0501.2009.01769.x. (AU)

• Processo FAPESP: 03/04585-1 - Avaliacao da contaminacao peri e intra-implantar e de proteses rosqueadas sobre implantes dentarios.
• Beneficiário: Rubens Ferreira de Albuquerque Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular