Influence of Selected Restorative Materials on the Environmental pH: In Vitro Comparative Study

Anna Lehmann,Maria Misiaszek,Kacper Nijakowski,Anna Surdacka,Michalina Nowakowska,Patryk Woś

doi:10.3390/app112411975

Abstract

In dental caries treatment, it is worth using such restorative materials that may limit plaque accumulation. The pH of the filling seems to be an important factor affecting the potential bacterial colonisation. Our study aimed to assess how selected restorative materials influence the environmental pH. A total of 150 specimens (30 of each: Ketac Molar, Riva LC, Riva SC, Filtek Bulk Fill, and Evetric) were placed in 100 sterile hermetic polyethene containers with saline and stored in 37 °C. The pH of each sample was measured using the electrode Halo HI13302 (Hanna Instruments, Poland) at specific points in time for 15 days. The initial pH levels were significantly lower for glass ionomer cements (3.9–4.7) compared to composites (5.9–6.0). With time, the pH increased for samples with glass ionomer cements (by nearly 1.5), whereas it decreased for samples with composites (maximally by 0.8). In the end, all materials were in the pH range between 5.3 and 6.0. The highest final pH was obtained with Ketac Molar at about 5.9. Double samples had lower pH values than single samples, irrespective of the type of material. In conclusion, immediately after application, restorative materials decreased the environmental pH, especially light-cured glass ionomer cements. For glass ionomers, within two weeks, the pH increased to levels comparable with composites.

Highlights

Acid demineralisation of enamel due to the metabolic activity of bacterial plaque is the first stage of the caries process, leading to the formation of a cavity [1,2,3]
Numerous in vitro studies show that at acidic pH, the surface of the composite material is more stable than the surface of glass ionomer cement [4,5,6]
For Evetric composite material, significant differences were observed in pH level depending on the number of samples during the first three days

Summary

Introduction

Acid demineralisation of enamel due to the metabolic activity of bacterial plaque is the first stage of the caries process, leading to the formation of a cavity [1,2,3]. The destructed dental tissues are restored with various materials; on the contact surface of the tooth and the filling, there is usually a niche that favours the plaque accumulation and may increase the risk of secondary caries. It is worth using such restorative materials that may prevent bacterial adhesion or limit the development of bacterial plaque. Numerous in vitro studies show that at acidic pH, the surface of the composite material is more stable than the surface of glass ionomer cement [4,5,6]. Conventional glass ionomer cements (GICs) can buffer lactic acid and release fluoride, which appears to be very beneficial in a clinical approach [7,8,9]

Methods

Results

Discussion

Conclusion