Methods: Three different antibiotic pastes: tigecycline, minocycline and ciprofloxacin; were mixed with sterile water. The final concentrations required to achieve adequate thick consistency were 0.55mg/µl; 0.34mg/µl; and 0.42mg/µl respectively. Twenty-eight extracted anterior teeth were sterilized and divided into three groups. The root canal of each tooth was prepared and filled with one of the antibiotic pastes. The tooth color changes were analyzed with a spectrophotometer (VITA Easyshade) before and after treatment: at 0, 2, 7, 10, 14, 21 and 28 days to generate a tooth color value according to the CIE L*a*b* system. The change in color was determined as ΔL, Δa, Δb (the difference in the value of the color) and ΔE (color difference between two samples).
Results: Both tigecycline and minocycline groups had significantly greater discoloration in comparison with the control ciprofloxacin group (p<0.01). The discoloration increased every week, with visibly darker crowns seen at the end of 4 weeks. Tigecycline showed a non-significantly different ΔL*, Δa*, Δb* and ΔE* values compared with the minocycline group. However, after adjusting for concentration, the minocycline group had significantly darker discoloration compared with the tigecycline group (p<0.01).
Conclusions: Both tigecycline and minocycline may cause tooth discoloration. However, based upon these initial results, it appears that tigecycline might be less discoloring than minocycline.
Keywords: Endodontics, Regeneration, Stain, Teeth and Tigecycline