Pathomorphological distinction between Er:YAG and diode lasers on the excisional biopsy of the oral mucosa

Abstract

Background -In oral pathology, laser devices can provide important advantages, especially in the treatment of certain lesions. However, there is controversy about the use of some wavelengths in the analysis of suspected dysplastic or neoplastic lesions, raising doubt about the laser's suitability for use in biopsy procedures. The present pilot study evaluates the pathomorphological characteristics and suitability of Er:YAG and diode lasers for performing excisional biopsies in the oral mucosa with special emphasis on the extent of the thermal damage zone created. Material and Methods -10 patients were randomly assigned to one diode or one Er:YAG laser groups. The Er:YAG laser(2940nm) was used in a pulsed wave mode 200mJ/35Hz with a power of 7 W. Power settings for the diode laser(810 nm) were 3 W in a pulsed mode. The thermal damage zone of the two lasers and intraoperative and postoperative complications were assessed and compared.All biopsy specimens were evaluated by optical microscopy by threeblinded pathologists. After establishing the pathomorphological diagnosis of the lesion assessed, the pathologists measured the maximal width of the peripheral thermal damage zone in the specimen in μm and classified it using appropriate index. Results -The peripheral thermal damage zone on the borders of the excisional biopsies was significantly smaller with the Er:YAG laser compared to the diode laser regarding values in μm or pathomorphological index scores. No postoperative complications occurred in any of the two groups. Conclusions -The Er:YAG laser seems to be appropriate for excisional biopsies of benign oral mucosal lesions. The Er:YAG laser offers clear advantages in terms of smaller thermal damage zones over the diode laser. Although in some samples thermal damage was minimally visible, in all samples histological evaluation was clearly possible. The study demonstrated that the Er:YAG laser can be safely used in oral biopsy investigations while ensuring a successful histological evaluation, which is fundamental to correct clinical management.

Er:YAG Laser Assisted Vestibuloplasty: A Case Report

“…Water is the dominant target chromophore for Er:YAG laser energy which currently has the highest absorption peak in water among any commercially available, FDA-approved dental lasers. These unique characteristics of the Er:YAG laser allow performing of very narrow layers of thermal mechanical tissue ablation with minimal collateral thermal consequences [8].…”

“…This can be accomplished because of the unique characteristics and photobiology of the Er:YAG laser tissue interaction. In contrast to other laser systems the Er:YAG does not have haemostatic properties, but the healing process after Er:YAG laser surgery is faster, without thermal damages and necrosis [8]. With the addition of the Er:YAG laser, the general dentist is presented with a less stressful and more beneficial treatment protocol for soft-tissue excisional procedures than previously available with the older continuous wave diode or pulsed CO 2 lasers alone [9].…”

Comparison of the Coagulation Effect of Different Types of Laser Crown Lengthening

“…The main plus compared to the other instruments is the water cooling, which makes the manipulations more gentle, the reactions (pain, edema and erythema)vague and the healing processfaster (3,5,7,8,9,10,12). The diode laser has a lot of advantages as well, although its results compared to the others are poor (3,4,6,7,12). The coagulation and hemostasis in-depth are well defined, which from the clinical point of view equals lack of bleeding.…”

Advanced Applications of the Er:YAG Laser in Oral and Maxillofacial Surgery

“…Er: YAG lasers are not well absorbed in hemoglobin as the soft tissue diode lasers are, so hemostasis can be an issue with these wavelengths. Some studies [18][19][20][21][22][23] compared the efficacy of diode and Er: YAG lasers in soft tissue oral surgery. Some studies showed that the Er:YAG laser induced deeper gingival tissue injury than diode laser, as judged by bleeding at surgery, delayed healing and deformed specimen for histopathological analysis [23].…”

“…Some studies [18][19][20][21][22][23] compared the efficacy of diode and Er: YAG lasers in soft tissue oral surgery. Some studies showed that the Er:YAG laser induced deeper gingival tissue injury than diode laser, as judged by bleeding at surgery, delayed healing and deformed specimen for histopathological analysis [23]. In some studies the use of diode laser showed additional advantages over Er: YAG in terms of less postoperative discomfort and pain, but some studies show no difference between these two lasers [3].…”