A preliminary study of healing of superpulsed carbon dioxide laser incisions in the hard palate of monkeys

Background and Objective: Prior studies of laser wound healing using differ ent animal models have shown a delay ed tissue response after carbon dioxid e (CO,) laser application. This article reports on the preliminary findings of healing of superpulsed CO2 laser and scalpel incisions in the hard pala te of monkeys. Study design/Materials and Methods: Twelve parallel incisions using a super pulsed, continuous wave CO, laser and a scalpel were performed in the hard palate of each of two adult monkeys at 3, 7, and 14 days time schedules. Po wer levels of 2.0, 4.0, and 6.0 Watts were used for the laser incisions. Wo unds were harvested, fixed in 10% formalsaline for at least 48 hours and pr ocessed routinely. Each specimen was embedded in paraffin wax at 90 degrees to the surface epithelium and 5 mu m thick sections prepared for staining with haematoxylin and eosin, Periodic acid Schiff and Masson-trichrome at a step-serial interval of 100 mu m. Sections were evaluated independently. Results: According to the clinical findings we showed a wound closure in al l of the wounds (laser and scalpel incisions) at 3, 7, and 14 days of heali ng. Histologically, we showed that laser incisions at three and seven days demonstrated an increased, power setting-dependent tissue necrosis and mark ed inflammatory response with minimal organization compared to scalpel inci sions. At 14 days both types of incisions exhibited complete wound healing of the epithelium and connective tissue. Discussion and Conclusions: According to these preliminary results, superpulsed CO, laser tends to produce more pronounced changes (due to tissue thermal damage) wit h corresponding greater inflammatory reaction and delay in tissue organizat ion only initially. (C) 1999 Wiley-Liss, Inc.