[Bacterial contamination of bony particles from the bone collection trap]

Intraoral bony defects can be filled with bony particles that are collected in a titanium filter while drilling. The rinsing liquid is contaminated with blood and saliva which implies that the bony particles are also contaminated with bacteria. The aim of this study was to determine quantitatively and qualitatively the degree of this contamination. Over a period of three months bony particles were collected from 50 patients undergoing surgery. The bony particles were scraped off the filter, resuspended and incubated aerobically and anaerobically on human blood agar media. Colony forming units (CFU) were determined as well as the most common species of bacteria. All samples showed anaerobic and aerobic growth. After anaerobic incubation in 44 samples the number of bacteria was higher (38) or equal (six) to that after aerobic incubation. On average 435,000 CFU (aerobic) and 1,013,000 CFU (anaerobic) per sample were found. The most frequently identified bacteria belonged to Veillonella spp. in the anaerobic and to Streptococcus oralis in the aerobic cultures. In 43 samples black pigmented colonies were detected. There were only bacteria identified which are common in the oral cavity.