Effect of Citric Acid and Chlorhexidine on the Implant Surface-an Invitro Experiment

Objectives: To find out and compare the effect of citric acid and chlorhexidine on the surface roughness and elemental composition of dental implants and to find out the effect of duration and concentration of citric acid and chlorhexidine treatment on the surface of dental implants.Material and Methods: 135 specimens were prepared by sectioning 15 dental implants and abutments.These were embedded in polyvinylsiloxane putty blocks such that the sectioned surface was exposed.The specimens were subjected to the various surface treatments viz; immersion in 30%, 40%, 50% and 60% citric acid and 0.2% chlorhexidine for different durations viz; 40 sec, 60 sec and 80 sec.Surface roughness and elemental composition of the specimens were analysed using profilometer, scanning electron microscope and energy dispersive spectroscopy respectively, before and after immersion in different solutions.Data obtained was statistically analysed using factorial ANOVA. Results:The highest mean surface roughness on implant specimens was obtained with 50% citric acid and the least roughness was observed with 30% citric acid.On the abutment specimens, the highest mean surface roughness was observed with a concentration of 40% citric acid and the least roughness was with 30% citric acid.Chlorhexidine showed lower roughness both in implant and abutment specimens.The elemental analysis for implants as well as abutments showed decrease in elemental titanium with increase in surface roughness.The greatest concentration of elemental titanium was present at 30% citric acid for 40 sec and 0.2% chlorhexidine at 40 sec for implants, and 30% citric acid for 60 sec and 0.2% chlorhexidine at 40 sec for abutments. Conclusion:Surface treatment of dental implants and abutments with citric acid and chlorhexidine increased the surface roughness.The surface roughness of implants and abutments increased along with an increase in the duration of immersion in Citric acid and Chlorhexidine.Increase in surface roughness of implants and abutments caused a decrease in elemental titanium concentration.Titanium concentration is maintained when implants and abutments are treated with 30% citric acid.The clinically acceptable concentration of citric acid is 30% for 40 sec and 0.2% chlorhexidine for 40 sec to be used in surface conditioning decontamination of failing implants.