In vitro study of the soft tissue effects of microsecond-pulsed CO(2) laser parameters during soft tissue incision and sulcular debridement.

Background And Objectives: Carbon dioxide (CO(2)) lasers are an important part of dental treatment. Advances in laser technology have produced microsecond pulse durations and small beam sizes. The histological effects of porcine intraoral soft tissue with a range of microsecond-pulsed CO(2) laser parameters used for incision and sulcular debridement were evaluated in vitro and compared with historical histologic data.

Study Design/materials And Methods: Fresh pig mandibles were used to perform incision and sulcular debridement using a microsecond-pulsed CO(2) laser. lambda = 10,600 nm, articulated arm delivered non-contact with spot size 200 microm, 500 microm, and 1 mm, and focal distance of 1 mm. For sulcular debridement, epithelium within periodontal pocket (6 mm x 6 mm) was removed. Laser parameters for incision were from 30 Hz, 350 microseconds, 28 mJ and energy density of 143 J/cm(2) to 90 Hz, 1,000 microseconds, 60 mJ, and 1,911 J/cm(2). Width and depth of tissue removed, as well as coagulation effects of the tissue treated were measured. These were compared to historical histologic database. Laser-treated surfaces were observed qualitatively using scanning electron microscopy (SEM).

Results: All laser parameters studied were able to reach the defined simulation objectives in reasonable amounts of time, less than a minute for incision and <20 seconds for sulcular debridement. The depth of the cut was significantly greater than the historical 95% confidence interval, but equivalent for width, lateral, and deep coagulation to the historical database. Sulcular debridement was achieved with minimal coagulation, <100 microm. SEM analysis did not identify any alteration to enamel, dentin, or bone during sulcular debridement.

Conclusion: The treatment objectives of incision and sulcular debridement were achieved with minimal lateral and deep coagulation in reasonable amount of time. Microsecond-pulsed CO(2) lasers can be safely and effectively used for incision and sulcular debridement.