Root Caries Preventive Effect of Varnishes Containing Fluoride or Fluoride + Chlorhexidine/Cetylpyridinium Chloride In Vitro.

Gerd Göstemeyer,Helen Woike,Sebastian Schlafer,Sebastian Paris,Falk Schwendicke

doi:10.3390/microorganisms9040737

Abstract

Caries preventive varnishes containing only fluoride might differ from those containing a combination of fluoride and antimicrobial components in terms of mineralization properties and their impact on the cariogenic biofilm. We compared a fluoride and a fluoride + chlorhexidine (CHX)/cetylpyridinium chloride (CPC) varnish on root caries formation in vitro. One hundred bovine root dentin samples were allocated to five groups (n = 20/group): (1) 7700 ppm fluoride varnish (Fluorprotector S (F)), (2) experimental placebo varnish for F (F-P), (3) 1400 ppm fluoride + 0.3% CHX/0.5% CPC varnish (Cervitec F (CF)), (4) experimental placebo varnish for CF (CF-P), (5) untreated control. Cariogenic challenge was provided using a multi-station, continuous-culture 3-species (Streptococcus mutans (SM), Lactobacillus rhamnosus (LR), Actinomyces naeslundii (AN)) biofilm model for 10 days. Mineral loss (ΔZ) was evaluated using transversal microradiography and bacterial counts in the biofilm assessed as colony-forming units. Fluorescence in situ hybridization (FISH) and confocal microscopy were performed to assess the three-dimensional biofilm architecture. Mean ± SD (vol% × μm) ΔZ was significantly lower for F (9133 ± 758) and CF (9835 ± 1677) compared to control (11362 ± 919) (p < 0.05), without significant differences between F and CF. SM counts were significantly lower and LR counts significantly higher in F- and CF-biofilms compared to control. AN counts were significantly higher in the F-biofilms than in all other groups. According to FISH, SM and LR invaded dentinal tubules only in the control-group. In the CF-group, the basal biofilm layer did not contain SM and AN. Both F and CF varnishes had similar caries-preventive effects and a considerable impact on biofilm structure and composition.

Highlights

In most industrialized countries, there is a general trend that individuals retain more teeth into higher ages [1,2]
The root caries prevalence is high in older individuals and the demand for root caries management strategies can be expected to increase in the near future [4,5]
Given the high prevalence of root caries in the older population, there is a high demand for effective root caries preventive agents

Summary

Introduction

There is a general trend that individuals retain more teeth into higher ages [1,2]. As gingival recessions often occur during aging, the root surfaces of these retained teeth are often exposed to the oral cavity, which increases the risk for caries development [3]. The root caries prevalence is high in older individuals and the demand for root caries management strategies can be expected to increase in the near future [4,5]. Cognitive decline and reduced mobility further limit the access to and provision of regular dental care for many older patients [9,10,11]. The application of effective preventive measures is important in the management of patients at risk for root caries [12]

Objectives

Methods

Conclusion