Abstract
Various medicaments containing calcium hydroxide [Ca (OH) 2] have been used for root canal medication or temporary root canal filling. The aim of this study was to evaluate OH-diffusion through the root canal after Ca (OH) 2medicaments were dressed in the root canals of extracted human teeth.
Forty-five extracted human mandibular anterior teeth with a single root canal were used. After root canal preparation, they were divided into nine groups of five teeth each, and all of the root canals were filled with one of the following medicaments: a) soft-type Ca (OH) 2paste (powder: liquid= 1: 1.2), b) medium-type Ca (OH) 2paste (1: 1), c) hard-type Ca (OH) 2paste (1: 0.9), d) paper point dressed with b), e) Calkil, f) Calcipex, g) Calvital, h) Vitapex, and i) Ca (OH) 2point. In a), b), and c), sterilized saline was used as a liquid component. Then, all of the teeth were fixed in agar containing phenolphthalein, which turns red above pH 8.5. The color change of agar was considered to be the index of OH-diffusion. Photographs of them were taken at 1, 2, 3, 5, 10, 15, 30, 45, 60, 90, and 120 minutes later, and the results were statistically analyzed.
It was found that each group showed a different color change of agar. The red area was the largest in Group e) . In Groups f) and g), only a small red area was observed. Little color change was observed in Group h) . Groups d) and i) showed no color change. These results suggest that the powder-liquid ratio and the vehicles used for Ca (OH) 2medication in the root canal may influence the pH change of the periapical tissue.
