Histologic evaluation of thermal damage produced on soft tissues by CO2, Er,Cr:YSGG and diode lasers.
OBJECTIVE
The aim of this in vitro experimental study was to perform histological evaluation of the thermal effect produced on soft tissue irradiated with CO2, Er,Cr:YSGG or diode lasers.


METHODS
Porcine oral mucosa samples were irradiated with Er,Cr:YSGG laser at 1 W with and without water / air spray, at 2 W with and without water / air spray, and at 4 W with water / air spray, with CO2 laser at 1 W, 2 W, 10 W, 20 W continuous mode and 20 W pulsed mode and diode laser at 2 W, 5 W, and 10 W pulsed mode. The thermal effect was evaluated measuring the width of damaged tissue adjacent to the incision, stained positively for hyalinized tissue with Hematoxylin-Eosin and Masson Trichrome stains. Besides, histological changes in the irradiated tissue were described using subjective grading scales.


RESULTS
The evaluated lasers developed a wide range of thermal damage with significant differences between groups. The samples with lowest thermal effect were those irradiated with Er,Cr:YSGG laser using water / air spray, followed by CO2 and diode lasers.


CONCLUSIONS
Emission parameters of each laser system may influence the thermal damage inflicted on the soft tissue, however, the wave length of each laser determines the absorption rate characteristics of every tissue and the thermal effect.
Cercadillo-Ibarguren
Iñaki
I
University of Barcelona Dental School, Centro Médico Teknon, Instituto de Investigación IDIBELL, C/ Vilana 12, 08022-Barcelona, Spain.
España-Tost
Antonio
A
Arnabat-Domínguez
Josep
J
Valmaseda-Castellón
Eduard
E
Berini-Aytés
Leonardo
L
Gay-Escoda
Cosme
C
D000818:Animals; D002056:Burns / Q000473:pathology*; D054020:Lasers, Gas / Q000009:adverse effects*; D053844:Lasers, Solid-State / Q000009:adverse effects*; D009061:Mouth Mucosa / Q000293:injuries* / Q000473:pathology; D017695:Soft Tissue Injuries / Q000209:etiology* / Q000473:pathology; D013552:Swine