The purpose of this study was to determine the ability of long shelf-life milk to serve as a temporary storage medium for the maintenance of periodontal ligament (PDL) cell viability on avulsed teeth. PDL cells were plated onto 24-well culture plates and allowed to attach for 24 h. Minimal Essential Medium was replaced with regular pasteurized milk (refrigerated milk), long shelf-life milk (Parmalat), or Save-A-Tooth. Tap water served as the negative control, and Minimal Essential Medium served as the positive control. The tissue culture plates were incubated at 37 degrees C for 1, 2, 4, or 8 h. Cell viability was determined using a cell proliferation assay (CellTiter 96 AQ Assay) and absorbance read at 490 nm. ANOVA indicated that all media performed significantly better than tap water at all time periods. At 8 h, PDL cell viability in regular pasteurized milk and long shelf-life milk were significantly greater than in Save-A-Tooth (p < or = 0.001). There was no significant difference between regular pasteurized milk and long shelf-life milk at any time period. These results suggest that long shelf-life milk, which has the advantage of not requiring refrigeration, is as effective a storage medium for avulsed teeth as regular pasteurized milk and more effective than Save-A-Tooth.

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Bisphosphonates conjugated to fluoroquinolone antibacterials through an intermediate carbon had better activity than conjugates lacking the carbon. Virtually all molar-based activity of these esterified bisphosphonate derivatives was identical to that of its parent. De-esterified free-acid forms retained good activity against most Gram-negative bacteria, but not against Gram-positives. A free-acid derivative remained bound to washed bone and completely inhibited Staphylococcus aureus growth. The more potent parent, ciprofloxacin, failed to bind significantly, and bacterial growth occurred.

The purpose of this study was to evaluate the antimicrobial activity of several medication preparations in root canal dentin infected with Enterococcus faecalis. Roots of extracted bovine incisors were prepared to standardized cylindrical test specimens, 5 mm in height. The smear layer was removed and the samples were autoclaved and then incubated at 37 degrees C/5% CO2 for 24 h in brain-heart infusion (BHI) broth containing 7.0 x 10(4) colony forming units per ml of E. faecalis. The samples were washed in phosphate buffered saline and mounted to individual culture wells with sticky wax. Test medications were applied to fill the canal lumina; medication groups were: (a) sterile H2O (positive control); (b) a 10% mixture of 1.0 g Ca(OH)2 USP in 10 ml sterile H2O; (c) 10% Ca(OH)2 in 0.12% chlorhexidine gluconate (Peridex); (d) Peridex; and (e) uninoculated BHI (negative control). The samples were incubated at 37 degrees C/5% CO2 for 24 h. Dentin samples for quantitative microbiology were then obtained with consecutive sterile burs (ISO 029, 035, 042). All three experimental groups demonstrated significantly greater antimicrobial activity than the positive control (p < 0.001). Group 2 demonstrated significantly greater antimicrobial activity than Group 3 or Group 4 at all dentin depths (p < 0.05). These results suggest that 10% Ca(OH)2 may be more effective than Peridex or 10% Ca(OH)2 in Peridex for the elimination of E. faecalis from dentin tubules.

The purpose of this study was to evaluate the antimicrobial activity of several calcium hydroxide (Ca(OH)2) preparations in root canal dentin infected with Enterococcus faecalis. Roots of extracted bovine incisors were prepared to standardized cylindrical test specimens of 5 mm in height; the smear layer was removed, and the specimens were incubated for 24 h at 37 degrees C in bacteriological culture medium that contained 7.0 x 10(4) colony forming units per milliliter of E. faecalis. The specimens were mounted in individual 4-mm diameter culture wells, and the test material was applied to fill the canal lumen. There were five treatment groups: group 1, a thick mixture of Ca(OH)2 USP (1.0 g/ml H2O); group 2, a thin mixture of Ca(OH)2 USP (0.1 g/ml H2O); group 3, Pulpdent TempCanal paste; group 4, sterile H2O (positive control); and group 5, 25 dentin specimens in sterile, uninoculated brain-heart infusion broth that were included as negative controls. Quantitative microbiological analysis of dentin at various depths was completed after 24 h. All groups showed a significant (p < 0.001) decrease in numbers of E. faecalis in all depths of dentin compared with the control. Groups 2 and 3 demonstrated significantly greater antimicrobial activity (73%-86% reduction) at all depths of dentin tested compared with group 1 (13%-26%) (p < 0.05). These results suggest that Ca(OH)2 can decrease the numbers of E. faecalis at all depths of dentinal tubules within 24 h and that thin preparations of Ca(OH)2 may be more effective in the elimination of E. faecalis from dentinal tubules than thick preparations.