title: Antibacterial and physical properties of resin modified glass-ionomers combined with chlorhexidine.
abstract: The purpose of this study was to determine the effect on mechanical properties and antimicrobial activity of the addition of chlorhexidine (CHX) to a resin modified glass-ionomer (Photac-fil, ESPE, Norristown, PA, USA). Chlorhexidine diacetate was combined with a resin modified glass-ionomer material at a concentration of 5%. The samples were tested for hardness, tensile strength and erosion at 24 h and 6-week intervals and for elution of CHX and antimicrobial activity weekly for 6 weeks. At 24 h there was no significant difference in hardness between the two groups, but at 6 weeks the resin modified glass-ionomer group was significantly harder than the CHX groups (P < 0.05). The diametral tensile strength test indicated no difference between the control and CHX groups at 24 h or at 6 weeks. The jet erosion test demonstrated significantly less erosion with the CHX group at 24 h but at 6 weeks the CHX group showed significantly more erosion than the control group. The chemical assay data demonstrated a peak elution of CHX at week 1 with residual amounts at weeks 2 and 3. The microbial data demonstrated that the CHX group had a significant reduction in Streptococcus mutans numbers for weeks 1-3, but after week 4 there was no difference between the glass-ionomer with and without CHX. The addition of CHX to resin modified glass-ionomer altered hardness and erosion of the resin-modified glass-ionomer, but because there are no material specifications, it is difficult to determine clinical implications. Chlorhexidine did significantly improve the antimicrobial effect of the glass-ionomer which was consistent with the chemical assay data. The results indicated that the addition of CHX to resin modified glass-ionomer material (Photac-fil) did not seriously degrade the physical properties during the time period tested and that the addition of CHX resulted in a greater reduction in S. mutans when compared with glass-ionomer alone.
authors.affiliation: Department of Oral Facial Development, Indiana University School of Dentistry, Indianapolis 46202-5200, USA. bjsander@iupui.edu
authors.forename: B J
authors.initials: BJ
authors.lastname: Sanders
authors.forename: R L
authors.initials: RL
authors.lastname: Gregory
authors.forename: K
authors.initials: K
authors.lastname: Moore
authors.forename: D R
authors.initials: DR
authors.lastname: Avery
mesh_terms: D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000737:chemistry* / Q000494:pharmacology*; D002710:Chlorhexidine / Q000737:chemistry* / Q000494:pharmacology*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006244:Hardness; D008422:Materials Testing; D012117:Resins, Synthetic / Q000737:chemistry*; D013295:Streptococcus mutans / Q000187:drug effects; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D000891:Anti-Infective Agents, Local; D005899:Glass Ionomer Cements; C081144:Photac-Fil; D012117:Resins, Synthetic; D002710:Chlorhexidine