No abstract

Summary. Sealapex was compared with two other root canal sealers for leakage in gutta‐percha filled extracted teeth using a silver stain technique. The extent of leakage in vitro in the root canal systems over a 30‐day period between the three root canal sealers was not statistically different. However, each sealer group leaked significantly less than the control group filled with gutta‐percha only. The results support previous findings that a sealer with gutta‐percha prevents apical leakage of the root canal system.

Both length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis for replanted teeth. Numerous studies have examined various media in an attempt to determine the ideal material for storage of the avulsed tooth. The purpose of this study was to compare the number of viable periodontium ligament (PDL) cells in different storage media using a collagenase assay. Thirty-three freshly extracted human teeth were divided into four experimental and two control groups. The positive and negative controls corresponded to 0 min and an 8-h dry time, respectively. The experimental teeth were stored dry for 30 min and then immersed in one of four media (Hank's balanced salt solution (HBSS), milk, saline, water) for 45 min. The teeth were then treated with dispase grade II and collagenase for 30 min. The number of viable and nonviable PDL cells was counted with a hemocytometer and analyzed. An ANOVA demonstrated no statistically significant differences in the viability of PDL cells among saline, HBSS and milk. Within the parameters of this study, it appears that milk or saline is an equally viable alternative to HBSS for storage of avulsed teeth.

One of the key factors for obtaining a favourable long-term prognosis in avulsed teeth is maintenance of the vitality of the periodontal ligament (PDL) cells. Most studies which have examined PDL cell vitality have used neutral red or trypan blue as stains. However, these stains have certain inherent disadvantages. The purpose of this paper was to (i) evaluate the use of saline and milk as storage media for PDL cells and (ii) determine the value of using fluorescein diacetate (FDA) as a staining medium for vital PDL cells on the root surface of avulsed teeth. Thirty-two single-rooted premolars were utilized from patients aged 13 to 28 years. Following atraumatic extraction, the teeth in the experimental groups were air dried for 10 min and then placed in either milk or saline for 120 min. Both control and experimental teeth were subjected to trypsinization procedures, staining with FDA, and haemocytometer readings to determine the number of vital cells. There was no statistically significant difference in the number of viable cells on the root surfaces of teeth after 2 h of storage in either milk or in saline. Furthermore, staining with FDA provided an excellent method by which to determine PDL cell vitality.

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