J Oral Laser Applications 8 (2008), No. 4 (12.01.2009)
Effect on Pulp Healing of CO2 Laser Irradiation and Direct Pulp Capping with Experimentally Developed Adhesive Resin Systems Containing Reparative Dentin-promoting Agents
Ogisu, Takahito / Suzuki, Masaya / Shinkai, Koichi / Katoh, Yoshiroh
Purpose: The purpose of this study was to examine the reaction and hard tissue derivation of rat pulp directly capped with experimentally developed adhesive resin systems after CO2 laser irradiation.
Materials and Methods: The experimentally developed bonding agents used for direct pulp capping contained four kinds of calcium phosphate: hydroxyapatite, dicalcium phosphate dehydrate, ß-tricalcium phosphate, and octacalcium phosphate, as well as Mega Bond (MB) primer (MBP) used for adhesive treatment. The intensities of irradiation of the CO2 laser were set at three stages: low, medium (standard) with LLLT action, and high. The 12 experimental groups were formed by combining the three laser groups with four kinds of experimentally developed bonding agents. MBP was applied to the control group after direct pulp capping with Dycal without laser irradiation. In all groups, the cavities were filled with Clearfil AP-X and photopolymerized. Histopathological and immunohistochemical examinations were undertaken 3, 7, and 14 days after direct pulp capping.
Results: There was no significant difference in the wound healing of exposed pulp among the laser-irradiated experimental groups. However, the group irradiated with the low-intensity laser showed faster pulp healing and dentin bridge formation than the other laser groups.
Conclusion: There was no significant difference in wound healing of exposed pulp between each experimental group and the control group. It was suggested that low irradiation condition of CO2 laser and direct pulp capping with experimentally developed bonding agents containing calcium phosphate were comparable to the preparation of calcium hydroxide DY. The thickness of irritative dentin formed on the pulpal wall showed a tendency to increase as the intensity of irradiation was raised.
Keywords: direct pulp capping, experimental adhesive resin system, reparative dentin-promoting agent, CO2 laser, rat pulp, dentin bridge