Tooth discolouration and internal bleaching after the use of triple antibiotic paste

Abstract

AimTo assess the discolouration of teeth with closed and open apices after placement of triple antibiotic paste (TAP, ciprofloxacin, metronidazole and minocycline) in the pulp chamber and whether discolouration could be reversed by internal bleaching procedures. MethodologyTwenty extracted human mandibular premolars were divided into 2 groups (n=10): teeth with closed apices (CA) and teeth with open apices (OA). After conventional access, the TAP was sealed in the pulp chamber for 3weeks. The paste was removed by a rinse with sodium hypochlorite (NaOCl) and a mixture of sodium perborate and distilled water was sealed in the pulp chamber for 1, 2 and 3weeks. The shade was measured by a spectrophotometer at six time periods: baseline (T0), after 3weeks of placement of TAP (T1), after removal of TAP with a NaOCl rinse (T2) and after 1 (T3), 2 (T4) and 3 (T5) weeks of internal bleaching with sodium perborate paste. Data were collected based on the CIELAB-CIE1976 (L*a*b*) system and analysed using t-tests and anova. ResultsA significant decrease in the mean values of L* (lightness) was observed after treatment with TAP (T1, P<0.05). Considerable increases in these values after bleaching with sodium perborate (T3<T4<T5) were found in both groups. The only significant difference in the intergroup analysis was between T1 and T2, in which E values in the OA group were higher (P=0.04). ConclusionsTAP discoloured the tooth structure, but discolouration could be reversed with sodium perborate paste. In general, teeth with closed and open apices had the same rates of discolouration and bleaching.