Mk. Caliskan et al., EFFECT OF CALCIUM HYDROXIDE AS AN INTRACANAL DRESSING ON APICAL LEAKAGE, International endodontic journal, 31(3), 1998, pp. 173-177
In this in vitro study, we investigated the effects of the use of two
different calcium hydroxide (Ca(OH2)) preparations as an intracanal dr
essing on the sealing ability of two different sealers were investigat
ed. Eighty-eight freshly extracted, single-rooted maxillary anterior t
eeth were used. After the root canals were hand-instrumented, they wer
e divided into six groups of 10 each. The root canals were dressed wit
h Ca(OH)(2) paste, either mixed with sterile water (in groups 1 and 2)
or with glycerine (in groups 3 and 4). The dressed root canals were i
ncubated in 100% humidity at 37 degrees C for 7 days. In groups 5 and
6, the root canals were not dressed. After the root canal dressings we
re removed by irrigation with 5.25% NaOCl and remaining with a K-type
file, all canals of the experimental groups were obturated with sealer
ant gutta-percha using a cold lateral condensation technique. Calciob
iotric Root Canal Sealer, (CRCS), (in groups 1, 3 and 5) and Diaket (i
n groups 2,4 and 6) were used as sealers. All specimens were placed in
India ink for 7 days, and the amount of apical leakage was scored. Ei
ght further prepared specimens were dressed with Ca(OH)(2) plus water
or Ca(OH)(2) plus glycerine and examined with scanning electron micros
copy (SEM) following the removal of dressings. There was a statistical
difference in the leakage patterns amongst the 6 experimental groups
(P < 0.05). Specimens in group 2 exhibited less leakage than the other
experimental groups, except group 4 (P < 0.05). There were no other s
ignificant interactions. SEM examination revealed that Ca(OH)(2) cryst
als were present on the surface of smear layer in both groups where Ca
(OH)(2) paste had been placed, but they did not penetrate into the den
tinal tubules.