Cultivatable bacteria in dentine after caries excavation using rose-bur or carisolv

To measure the amount of viable bacteria after excavation using conventional rose-bur or the chemo-mechanical Carisolv method, a total of 22 lesions were analyzed (one vital tooth per patient) in this open, controlled and randomized study. Two samples per lesion were taken under aseptic conditions using a rose-bur, one superficially in the caries lesion and one after completed excavation. In in vitro tests more material was collected from the hard caries free dentine as compared to the carious dentine. The samples were incubated on blood agar (aerobically and anaerobically), Rogosa (SL) agar and mitis salivarius (MS) agar. For blood agar (aerobic) both methods resulted in a significant decrease in CFU, for blood agar (anaerobic) and MS agar only the Carisolv method resulted in a significant decrease in CFU and for SL agar neither method resulted in a significant decrease in CFU. Comparing CFU before and after excavation, a considerable reduction of CFU was seen ranging from 10(1) to 10(4). Comparing the excavation methods, there were no significant differences, except in the case of blood agar (aerobic), which showed that Carisolv excavation was more effective in reducing CFU. This study indicated that bacterial sampling collected more material from hard dentine as compared from soft. Remaining bacteria after excavation were low in both groups. The Carisolv method seemed to remove bacteria at least up to and possibly beyond the extent of conventional drilling.