Chlorhexidine gluconate is currently the most effective oral antimicrobial agent against microorganisms, but discoloration of the teeth prevents its long-term use and can reduce patient cooperation. In this study, the effect of chlorhexidine and a diluted chlorhexidine-based, fluoride, cetylpyridinium and vitamin added mouth rinse (Orthokin) on stain index in fixed orthodontic patients was compared.

This study was performed as a double blind randomized controlled trial on 50 patients undergoing fixed orthodontic treatment in the age group of 14-30 years. The patients were categorized as two groups of chlorhexidine and Orthokin mouth rinses and were asked to use mouthwash for eight weeks. Groups were matched according to colouring food consumption. Extrinsic staining index was assessed by modified Loben technique. Data was analysed by SPSS software. P value was set to be 0.05.

In the chlorhexidine group, the stain extent index and overall stain index were increased significantly at 8 weeks (P<0.001 and P=0.002, respectively). However, the increase in stain intensity index was insignificant (P=0.07). In Orthokin group, the changes in stain extent, stain intensity and overall stain were insignificant (P=0.66, P=1.000, P=0.47, respectively).

According to the results of the present study, chlorhexidine mouthwash causes more staining of teeth compared to Orthokin mouthwash. It seems that lower concentrations of chlorhexidine can be prescribed to orthodontic patients. Although these compounds are effective in sense of oral hygiene, they do not cause significant discoloration.