Bacterial Counts in Carious Dentine under Restorations: 2–Year in vivo Effects

Abstract

Little is known about the long–term effects of fluoride–releasing materials on carious dentine in vivo. The aim was to investigate the 2–year influence of a resin–modified glass ionomer cement (RM–GIC) and amalgam on the bacteriological counts of carious dentine that remained under class I restorations. To enable a split–mouth design, 33 molar pairs in 33 patients (mean age 15.1 years, SD 1.4) were selected, based on clinically and radiographically diagnosed occlusal dentine caries. The enamel of the carious molars was removed, and the carious dentine was sampled under aseptic conditions just beneath the dentinoenamel junction. The molars were alternately restored with RM–GIC or amalgam without further removal of carious dentine. The samples were processed for microbiological determination of total viable counts (TVC), mutans streptococci (MS), and lactobacilli (LB). The molar pairs of 25 patients were reevaluated after 2 years using the same clinical techniques and were permanently restored after complete caries removal. Both materials showed a substantial decrease in numbers of TVC and LB of the carious dentine after the 2–year period. Compared to amalgam, the decrease in the numbers of LB was significantly more pronounced for RM–GIC. No microorganisms were detected in only 11 molars (6 RM–GIC and 5 amalgam) after the 2–year period. Based on this study, we suggest that complete removal of carious dentine is still the best conservative treatment, irrespective of the restorative material used.

A randomized clinical trial on the sealing of occlusal carious lesions: 3–4-year results

“…Since cavity preparation usually involves some loss of healthy dental tissue, alternative approaches have been proposed to preserve tooth structure, such as the sealing of carious tissue beneath sealants or restorations. These approaches may even reduce or completely eliminate the population of viable microorganisms, 1,2,3,4,5,6,7,8 thus controlling caries progression.…”

Quantity of Remaining Bacteria and Cavity Size After Excavation with FACE, Caries Detector Dye and Conventional Excavation In Vitro

“…2 At the same time, removal of carious dentin is necessary prior to restoring the tooth. 3 Although there still is no definitive guideline as to how much infected dentin may be allowed to remain in the cavity, it is generally accepted that heavily infected dentin needs to be removed and minimal quantities of bacteria may be left in the cavity in order to preserve dentin. [4][5] A clinically relevant method for assessing new caries excavation methods should both quantify the infected dentin remaining in the cavity after excavation and assess the amount of dentin that has been removed.…”

Antimicrobial activity of alexidine, chlorhexidine and cetrimide against Streptococcus mutans biofilm

“…These techniques show success in clinical studies and microbiological reports examining bacterial presence after such procedures have demonstrated that the number of microorganisms is reduced after incomplete carious dentin removal and tooth sealing [5][6][7][8][9]. However, the persistence of viable bacteria in dentin after these techniques has raised doubts regarding the long-term effectiveness of treatment [31]. Streptococcus mutans are cariogenic bacteria that may be found on sealed carious dentin [2,[6][7][8][9].…”