In vitro osteogenic potential of an experimental calcium silicate-based root canal sealer.
OBJECTIVE
This in vitro study compared the cytotoxicity and osteogenic potential of an experimental calcium silicate-based sealer with an epoxy resin-based sealer (AH Plus; Dentsply Caulk, Milford, DE) and a zinc oxide-eugenol-based sealer (Pulp Canal Sealer; SybronEndo, Orange, CA).


METHODS
Disks prepared from the respective sealer and from Teflon (negative control) were placed in direct contact with a MC3T3-E1 osteogenic cell line at 6 weekly intervals after immersion in a culture medium. Succinic dehydrogenase activities were evaluated using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Extracts from these sealers after the 6-week immersion period were investigated also by MTT assay. Aged sealers were then switched to an osteogenic medium for examination of the alkaline phosphatase activity and mineralization of extracellular matrices produced by the differentiated cells.


RESULTS
All sealers exhibited severe toxicity after 24 hours, after which toxicity decreased gradually over the experimental period except for Pulp Canal Sealer, which remained severely toxic. Toxicity of the extracts derived from the sealers was concentration dependent, with those derived from the experimental sealer being the least cytotoxic at a 1:10 dilution. Minimal alkaline phosphatase activity and no bone formation were seen with Pulp Canal Sealer. The production of alkaline phosphatase was less intense for the experimental sealer at 7 days. However, both AH Plus and the experimental sealer did not inhibit mineralization of the extracellular matrix after 28 days.


CONCLUSIONS
The experimental calcium silicate-based sealer may be regarded as minimally tissue irritating and does not interfere with bone regeneration even when it is inadvertently extruded through the apical constriction.
Bryan
Thomas E
TE
Department of Endodontics, School of Dentistry, Medical College of Georgia, Augusta, GA 30912-1129, USA.
Khechen
Khaled
K
Brackett
Martha G
MG
Messer
Regina L W
RL
El-Awady
Ahmed
A
Primus
Carolyn M
CM
Gutmann
James L
JL
Tay
Franklin R
FR
D016475:3T3 Cells; D000469:Alkaline Phosphatase / Q000032:analysis; D017607:Aluminum Compounds / Q000494:pharmacology / Q000633:toxicity; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology* / Q000633:toxicity; D017610:Calcium Compounds / Q000494:pharmacology* / Q000633:toxicity; D002470:Cell Survival; D004396:Coloring Agents; D017077:Culture Media, Conditioned; D004338:Drug Combinations; D004853:Epoxy Resins / Q000494:pharmacology / Q000633:toxicity; D005109:Extracellular Matrix / Q000187:drug effects; D008422:Materials Testing; D051379:Mice; D046529:Microscopy, Electron, Transmission; D008903:Minerals / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects*; D010087:Oxides / Q000494:pharmacology / Q000633:toxicity; D012387:Root Canal Filling Materials / Q000494:pharmacology* / Q000633:toxicity; D017640:Silicates / Q000494:pharmacology* / Q000633:toxicity; D016622:Silver Staining; D013385:Succinate Dehydrogenase / Q000032:analysis; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D015035:Zinc Oxide-Eugenol Cement / Q000494:pharmacology / Q000633:toxicity
D017607:Aluminum Compounds; D001672:Biocompatible Materials; D017610:Calcium Compounds; D004396:Coloring Agents; D017077:Culture Media, Conditioned; D004338:Drug Combinations; D004853:Epoxy Resins; D008903:Minerals; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; D013778:Tetrazolium Salts; D013844:Thiazoles; D015035:Zinc Oxide-Eugenol Cement; C534916:epoxy resin-based root canal sealer; C086631:mineral trioxide aggregate; D013385:Succinate Dehydrogenase; D000469:Alkaline Phosphatase; C022616:thiazolyl blue; C031293:calcium silicate