Adherence of Streptococcus mutans and Adsorption of Salivary Protein to Resin Composites Containing S-PRG Fillers

The purpose of this study was to measure the amount of adsorption of various salivary proteins to a resin composite having various amounts of surface pre-reacted glass-ionomer (S-PRG) fillers, and to make a comparative study of the adherence of S. mutans to the resin composite covered by various salivary proteins. We experimentally produced resin composites (S-PRG resin) having the basic composition of Bis-GMA/TEGDMA and various amount of the S-PRG fillers ranging between 0 60 wt%. Each S-PRG resin block was soaked in 5 kinds of components found in salivary fluid (Mucin 1, Lactoferrin, IgA, Cystatin C, and Lysozyme), and the amount of adsorption was measured by use of a spectrophotometer. The amount of the adsorption of salivary Mucin 1 was higher than that of any other salivary component tested regardless of the percentage of the S-PRG filler. In the case of salivary Lysoxyme used for coating, the amount of its adsorption increased with an increase in the percentage of the S-PRG filler. In addition, resin blocks coated with various salivary proteins were incubated at 37 ̊C for 2 hours with radio-labeled S. mutans for a quantitative adherence test. Labeled bacteria that adhered to the resin blocks were collected by using an automatic sample combustion system and a liquid scintillation counter. The absorbed salivary components, especially Mucin 1 and Lysozyme, inhibited the adhesion of S. mutans to the S-PRG resin; however, these changes were generally directional rather than statistically significant.