Pulp response and cytotoxicity evaluation of 2 dentin bonding agents.
OBJECTIVE
This study evaluated the biocompatibility of two dentin bonding agents (Clearfil Liner Bond 2 and Scotchbond Multi-Purpose) applied in human dental pulps and cell cultures.


METHODS
In vivo: Twenty human third molars that were scheduled for extraction were used. After cavity preparation, pulp exposure was achieved with a carbide bur. Hemorrhage control was obtained with saline solution. In 16 teeth, adhesive pulp capping was performed and the cavities were sealed with resin composite. In the control group (n = 4), pulps were capped with Ca(OH)2 and the cavities were sealed with IRM. Teeth were extracted 30 or 90 days following treatment and prepared for histological examination and bacterial detection. In vitro: materials were applied in Petri dishes, where NIH-3T3 cells were plated. The cells were counted 2, 4, and 6 days after plating to obtain the growth curves and to determine cell viability. All data were submitted to statistical analysis.


RESULTS
In vivo: Dentin bridge formation was seen in all teeth capped with Ca(OH)2, without an inflammatory response. Mild inflammatory responses and dentin bridge formation after 90 days were observed in 50% of specimens treated with Liner Bond 2. Pulps treated with Scotchbond Multi-Purpose presented mild to severe inflammatory response, and no mineralized tissue formation was detected. Bacteria were not disclosed in any specimen. In vitro: The cytotoxicity was similar between the two bonding agents, and both had statistically higher cytotoxic effects (P < 0.002) than Ca(OH)2.


CONCLUSIONS
Ca(OH)2 produced pulp healing in all teeth and exhibited lower cytotoxic effects than both adhesive systems; however, pulp healing was also observed under Liner Bond 2.
Demarco
F F
FF
Department of Operative Dentistry, Federal University of Pelotas, School of Dentistry, Rua Gonçalves Chaves 457, Pelotas, Rio Grande do Sul, Brazil 96015-560. sancha@uol.com.br
Tarquinio
S B
SB
Jaeger
M M
MM
de Araújo
V C
VC
Matson
E
E
D016475:3T3 Cells / Q000187:drug effects; D000328:Adult; D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials / Q000633:toxicity; D002126:Calcium Hydroxide / Q000627:therapeutic use; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003188:Composite Resins; D003737:Dental Cavity Preparation; D003782:Dental Pulp / Q000187:drug effects*; D003785:Dental Pulp Capping; D003793:Dental Restoration, Permanent; D003809:Dentin, Secondary / Q000033:anatomy & histology; D017220:Dentin-Bonding Agents / Q000627:therapeutic use* / Q000633:toxicity; D005500:Follow-Up Studies; D006801:Humans; D008689:Methacrylates / Q000627:therapeutic use / Q000633:toxicity; D008768:Methylmethacrylates / Q000627:therapeutic use; D051379:Mice; D008964:Molar, Third; D011671:Pulpitis / Q000209:etiology; D019279:Resin Cements / Q000627:therapeutic use / Q000633:toxicity; D013223:Statistics as Topic; D014945:Wound Healing; D015035:Zinc Oxide-Eugenol Cement / Q000627:therapeutic use
D001672:Biocompatible Materials; C112274:Clearfil Liner Bond 2; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D008768:Methylmethacrylates; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D015035:Zinc Oxide-Eugenol Cement; C031667:IRM cement; D002126:Calcium Hydroxide