Aim: The aim of this study was to detect the effect of dressing period of calcium
hydroxide medicament on the apical marginal leakage after obturation of root canal
system.
Materials and Methods: 80 freshly extracted single rooted human teeth were
selected ,all the root canals were hand-instrumented. They were randomly divided into four
groups of 20 teeth each. Group A has no intracanal medicament , groups (B,C,D) were
dressed with Ca(OH)2 paste for a different periods of time (7,14,30) days respectively,
groups (B,C,D) were divided into subgroups of 10 teeth according to removing of dressing
. The removal of ca(OH)2was done by two ways, 1- By irrigating with distilled water and
drying with paper points . 2- Size 40 k-file was used in slightly filing motion up to the
working length then irrigated with distilled water and drying with paper points. After that
all groups were obturated with lateral compaction technique using gutta-percha points and
zinc oxide-eugenol cement. Then the access was sealed with GIC cement. The teeth were
immersed into 2% mythylene blue solution ,The specimens were placed in an incubator at
37 C ,with moisture at 100%, for 7 days .After that the roots were sectioned
longitudinally and examined with stereomicroscope and liner leakage was measured.
Aim of Study: The antimicrobial intracanal medication was used widely, and the most common was calcium hydroxide dressing, which must be removed from the root canal before obturation, hence this study aimed to comparative efficacy of EndoVac and Navi
Tip 30 G irrigation Needles with Naocl and CHX 2% in removing calcium hydroxide dressing from the apical third of root canal. Materials &Methods: Forty single root and canal teeth were decoronated to the length of 16 mm. Each root was prepared to the apical foramen using ProTaper Universal Hand System to size 40. Each tooth was embedded in silicone putty to create a set matrix, which allowed reassembly of the tooth for irrigation tests after splitting longitudinally. Then each tooth was split into two halves and an artificial groove (L:4, W:0,2 , D:0,5 ) was cut in one half of the root canal wall 1 mm from the apex ,which was then filled with a Ca(OH)2 paste. Digital images were taken before reassembling under stereomicroscope X40. Subsequently the two halves of roots were reassemble with wax , and remounted in their silicone matrixes, then divided into 2 groups.