Use of checkerboard DNA-DNA hybridization to evaluate the internal contamination of dental implants and comparison of bacterial leakage with cast or pre-machined abutments

• Published in: Clinical oral implants research 2009-06, Vol.20 (6), p.571-577
• Main Authors: Do Nascimento, Cássio, Barbosa, Rodrigo Edson Santos, Issa, João Paulo Mardegan, Watanabe, Evandro, Ito, Izabel Yoko, De Albuquerque Junior, Rubens Ferreira
• Format: Article
• Language: English
• Subjects: Bacteria; bacterial leakage; Bacterial Typing Techniques - methods; checkerboard DNA-DNA hybridization; Dental Abutments - microbiology; Dental Implants - microbiology; Dental Leakage - microbiology; Dental Prosthesis Design; Dentistry; DNA Probes; DNA, Bacterial - analysis; Equipment Contamination; Humans; implant-abutment interface; microbiology/pathogenesis; Sensitivity and Specificity; Statistics, Nonparametric; Streptococcus sobrinus; Streptococcus sobrinus - genetics; Streptococcus sobrinus - isolation & purification; Surface Properties
• ISSN: 0905-7161; 1600-0501
• DOI: 10.1111/j.1600-0501.2008.01663.x

Aims: To evaluate the checkerboard DNA–DNA hybridization method for detection and quantitation of bacteria from the internal parts of dental implants and to compare bacterial leakage from implants connected either to cast or to pre‐machined abutments. Materials and methods: Nine plastic abutments cast in a Ni–Cr alloy and nine pre‐machined Co–Cr alloy abutments with plastic sleeves cast in Ni–Cr were connected to Branemark‐compatible implants. A group of nine implants was used as control. The implants were inoculated with 3 μl of a solution containing 108 cells/ml of Streptococcus sobrinus. Bacterial samples were immediately collected from the control implants while assemblies were completely immersed in 5 ml of sterile Tripty Soy Broth (TSB) medium. After 14 days of anaerobic incubation, occurrence of leakage at the implant–abutment interface was evaluated by assessing contamination of the TSB medium. Internal contamination of the implants was evaluated with the checkerboard DNA–DNA hybridization method. Results: DNA–DNA hybridization was sensitive enough to detect and quantify the microorganism from the internal parts of the implants. No differences in leakage and in internal contamination were found between cast and pre‐machined abutments. Bacterial scores in the control group were significantly higher than in the other groups (P