Cytotoxicity of substances leached or dissolved from pulp capping materials.
OBJECTIVE
To evaluate the cytotoxic effects of substances leached or dissolved from pulp capping materials on human pulp fibroblasts.


METHODS
The substances were applied to cell cultures in conditioned media. The experimental groups were: GI (control; n = 24)--cultures treated with fresh medium; GII (n = 24)--cultures treated with calcium hydroxide cement; GIII (n = 24)--cultures treated with adhesive resin and GIV (n = 24)--cultures treated with 37% orthophosphoric acid. The media were conditioned by placing the crude materials in contact with fresh culture medium for 1 h. The cytotoxicity analysis was performed using the Trypan blue dye exclusion assay at times of 0, 6, 12 and 24 h for cell viability assay, and at 1, 3, 5 and 7 days for survival assay. Data were treated by anova (P < 0.05) and Tukey's test (P < 0.05).


RESULTS
GI and II presented similar cell viability and cell growth. GIII and IV exhibited statistically significant lower percentages of cell viability: GIV only at the 0 h experimental time, whereas in GIII this viability markedly diminished reaching values of 10% by 12 h. Cell growth was impaired only in cultures of GIII.


CONCLUSIONS
Substances dissolved from the adhesive system tested were cytotoxic for human dental pulp fibroblasts in culture, whilst substances leached from calcium hydroxide were biocompatible.
Cavalcanti
B N
BN
Department of Endodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil. bncavalcanti@uol.com.br
Rode
S M
SM
Marques
M M
MM
D000134:Acid Etching, Dental; D001672:Biocompatible Materials / Q000633:toxicity; D017438:Bisphenol A-Glycidyl Methacrylate / Q000633:toxicity; D002126:Calcium Hydroxide / Q000633:toxicity; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004396:Coloring Agents; D017077:Culture Media, Conditioned; D003738:Dental Cements / Q000633:toxicity; D003764:Dental Materials / Q000737:chemistry / Q000633:toxicity*; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects; D003785:Dental Pulp Capping; D017220:Dentin-Bonding Agents / Q000633:toxicity; D005347:Fibroblasts / Q000187:drug effects; D006801:Humans; D008422:Materials Testing; D010756:Phosphoric Acids / Q000633:toxicity; D012995:Solubility; D013997:Time Factors; D014343:Trypan Blue
D001672:Biocompatible Materials; D004396:Coloring Agents; D017077:Culture Media, Conditioned; D003738:Dental Cements; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D010756:Phosphoric Acids; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; C030242:phosphoric acid; D014343:Trypan Blue; D002126:Calcium Hydroxide