In vivo Cariostatic Effect of Resin Modified Glass lonomer Cement and Amalgam on Dentine

Abstract

Fluoride-releasing materials have been reported to be bactericidal in vitro. This may be of benefit to modern dentistry, which is directed to the preservation of tooth tissue during restorative treatment. Little is known about in vivo effects. The aim is to investigate the influence of a resin-modified glass ionomer cement (RM-GIC) on carious dentine that remains under restorations, compared to amalgam. Using a split mouth design, 40 molar pairs in 40 patients (mean age 14.9 years) were selected, based on clinically and radiographically diagnosed occlusal dentine caries. Under aseptic conditions, the enamel was removed and the carious dentine was sampled just beneath the dentino-enamel junction using a round bur. Without further removal of carious dentine, the molars of a pair were alternately restored with RM-GIC or amalgam. The colour and the consistency of the carious dentine were assessed. The samples were processed for microbiological determination of total viable counts (TVC), mutans streptococci (MS), and lactobacilli (LB). After 6 months the molars were reopened, similarly sampled and evaluated, and then permanently restored after complete caries removal. For both materials a substantial decrease in the numbers of TVC, MS and LB was found after the 6-month period. Also a positive effect was observed on the colour and the consistency of the remaining carious dentine, which was comparable for the two materials. RM-GIC showed a significantly larger decrease in counts of MS and LB than amalgam, but not for TVC. Since in only few cavities the number of bacteria decreased under the level of detection, it is still considered essential to remove all carious dentine during restorative treatment.

Evaluation of Therapeutic Decision for Treatment of Carious Lesions by Dental Students

“…This finding reinforces the idea that some students continue to follow the basic principle that has regulated operative dentistry for centuries: namely, the removal of all tissue affected by a carious lesion, without considering its extent or depth [26][27][28]. Complete removal of carious dentine is not considered a prerequisite for halting lesion progression [29].…”

Adhesive restorative materials: A review

“…Many laboratory studies using, for example bacterial and demineralization-remineralization models, have suggested that GIC will prevent secondary caries. [36][37][38][39][40][41][42] Clinical studies have shown an effect of GIC on salivary fluoride levels, 43 acidogenic bacteria 44 and on demineralized dentine restored with GIC and worn in removable appliances. 45 There is anecdotal clinical evidence that secondary caries in association with GIC is at a very low level.…”

Indirect pulp treatment without re-entry in a permanent tooth: 36 months of follow-up

“…Some in vivo studies have shown less cariogenic plaque adjacent to GIC restorations 19 and other studies have demonstrated that enamel lesions can be easier remineralized as a result of fluoride release 20 and consequently diminish the risk for recurrent caries at cavity enamel margins 21 . Kreulen et al 22 affirmed that if enamel as well as dentine could benefit from material constituents of glass-ionomer cement, the use of GIC could be a first step towards a new caries therapy. The caries preventive effect of GIC is most likely related to its fluoride release, otherwise it has been shown that an initially high fluoride release decreases after 2-3 months 20 .…”