Marina Consuelo Vitale

Morphological, Histochemical, and Immunocytochemical Study of CO2 and Er:YAG Laser Effect on Oral Soft Tissues

OBJECTIVE The purpose of this study was to investigate the morphological, histochemical, and immunocytochemical changes of the oral mucosa after CO(2) or Er:YAG laser irradiation. BACKGROUND DATA There have been no comparative reports on CO(2) and Er:YAG laser effects on human oral soft tissues. MATERIALS AND METHODS Tissue preservation was studied in 40 oral biopsies of young patients obtained by CO(2) and Er:YAG laser surgery. Hematoxylin-eosin and Giemsa stains, PAS/diastase treatment, AE1 and AE2 cytokeratins, MiB1/Ki67, and bcl-2 immunoreactions were performed on the laser cut edges on formalin fixed, paraffin embedded biopsies. RESULTS CO(2) laser biopsies show blisters, clefts and erosions of the epithelium. Intracellular edema and lengthened nuclei were also seen. The glycogen content results decreased in CO(2) laser biopsies. Good expression for cytokeratins and cell-cycle proliferation markers were found in Er:YAG biopsies, on the contrary the apoptosis marker was better expressed in CO(2) laser biopsies. CONCLUSION The results suggest that Er:YAG laser may be routinely used in surgery, because of its minimal damage of the epithelial tissue, its low inflammatory reaction, its quicker healing process and its lower risk of scarring.

SEM Analysis of Dentin Treated with the Er:YAG Laser: A Pilot Study of the Consequences Resulting from Laser Use on Adhesion Mechanisms

OBJECTIVES The purpose of this study was to compare the morphological characteristics of lased dentinal surfaces obtained by chemical etching, which was applied either before or after laser treatment. The adhesive interface after the application of an adhesive-composite system on the above mentioned dentinal surfaces was also evaluated. MATERIALS AND METHODS Eighteen caries-free permanent molars were transversally cut to obtain the dentinal surfaces. Ten of these surfaces were divided into three main groups according to their preparation modality: laser only, laser followed by chemical etching, and chemical etching before laser. The Er:YAG laser was used with two different energy outputs: 200 and 400 mJ at 1 Hz. The eight remaining surfaces were divided into two groups and followed the same preparation as the first three groups. The only difference was a change in frequency: 4 Hz was used for treating these surfaces. An adhesive system (Scotchbond 1, 3M), a thin layer of flowable composite (Tetric Flow, Vivadent), and a regular composite (Z250, 3M) were applied to each dentinal surface and then separately light cured. In order to evaluate the dentine-restoration interface, the samples were cut longitudinally and prepared for SEM observation. RESULTS The dentinal surfaces that were etched by the laser treatment did not demonstrate the characteristics necessary for guaranteeing a good bond with the adhesive materials. A closer observation of the dentine-restoration interface revealed some micro-fractures located just below the lased dentinal surface. CONCLUSION The decision to use the Er:YAG laser as an alternative to conventional techniques of acid etching is currently arguable. Given that the available adhesive systems require acid conditioning, it would not be advisable to skip this operative step.

Diode laser irradiation and fluoride uptake in human teeth.

AIM: To evaluate chemically the effects of diode laser on fluoride uptake before and after laser irradiation of enamel surfaces. METHODS: Crowns of 20 sound human teeth were halved and a 3x3mm acid-resistant varnish uncovered window left for: A) no treatment; B) fluoride (Elmex gel); C) diode (fluoride + diode laser); D) diode (diode laser + fluoride). The dental surfaces were analysed using a fluoride ion-selective electrode, in order to evaluate the fluoride treatment in combination with a diode laser. Also, to investigate laser-induced compositional changes (contents in F-) in enamel before/after laser irradiation and topical fluoride application. RESULTS: The mean ±SD of fluoride uptake of teeth of group A was 1.55 ± 0.89 mg/l. Mean fluoride uptake increased sevenfold after fluoride gel treatment: 10.51 ± 3.38 mg/l for group B, up to 15 times after gel and laser treatment: 23.62 ± 3.58 mg/l for group C and was 22.7 ± 4.60 mg/l for group D (diode laser before fluoride application). The Kruskal Wallis test indicated a statistically significant effect of fluoride uptake for all three treatments (p<0.001). The Student-Newman-Keuls multiple comparison test indicated a statistically significant increase of fluoride uptake before and after all treatments, and also a statistically significant difference for laser treatment versus fluoride gel. However, there was no statistically significance difference between laser groups. CONCLUSIONS: There is an enhanced capability of lasers to increase fluoride uptake of enamel and providing. protection to enamel surface from acid attack.

Laser Light May Improve the Symptoms of Oral Lesions of Cicatricial Pemphigoid: A Case Report

OBJECTIVE The aim of this work is to report the handling of a patient suffering from cicatricial pemphigoid (CP) treated with laser phototherapy (LPT) and systemic steroids. BACKGROUND DATA CP is a group of rare chronic autoimmune blistering diseases that predominately affect the mucous membranes and occasionally the skin. The gingiva is most commonly involved, followed by the palate and the buccal mucosa. High-dosage systemic steroids are widely used for its treatment. LPT has been shown to improve wound healing and relieve pain. Its efficacy depends on the amount of energy delivered to the tissue, exposure time, and delivery method. MATERIALS AND METHODS A white 47-y-old man with CP who used systemic steroids for the previous 5 y was examined at our clinic. Extra- and intraoral examination revealed classic signs of the condition. LPT (GaAlAs diode laser, 660 nm wavelength, 30 mW, continuous wave, diameter approximately 3 mm, 60 J/cm(2) per session) was used in association with the steroids. LPT was performed in a punctual contact manner every other day on the oral mucosa. Maintenance of the treatment was carried out weekly because interruption of the LPT resulted in the recurrence of the lesions. At the time that this report was written, the patient had been undergoing twice weekly treatments for 6 months without signs of lesion recurrence. CONCLUSION Concomitant use of systemic steroids and LPT showed a positive effect on controlling oral CP lesions and on improving both oral health and the quality of life of the patient.

CO 2 -laser biopsies of oral mucosa: an immunocytological and histological comparative study.

The relationship between bioptic technique and tissue preservation has been studied in 18 oral biopsies of young patients obtained by electro surgery or CO2 laser surgery. Biopsies were formalin fixed, paraffin embedded and histologically, histochemically and immunocytochemically treated. All the biopsies show inflammatory cell infiltration, epithelial spongiosis, trichocariosis, supra basal small blisters, and epithelial clefts with lamina detaching from the corium. Histochemistry shows both the presence of edema and acid mucopolysaccharides inside the corium, and variable glycogen content in epithelial cells. Trichocariotic cells show a positive MiB1/Ki67 expression, when they are present. Nevertheless, laser biopsies show a lower amount of basophilic fibrous tissue and of bc12 bodies detection, connected with a higher amount of glycogen, Cytokeratin and MiB1/Ki67 expression in epithelial cells, compared to bovie biopsies. The result show a higher degree of damages in particular at the epithelial level, in electro surgery biopsies rather than laser biopsies. The best epithelial and corium preservation showed by laser biopsies suggest a chance of reversible condition, which can lead to a complete recovery due to its higher capability of restoring tissues.

Multicenter randomized, double-blind controlled trial to evaluate the efficacy of laser therapy for the treatment of severe oral mucositis induced by chemotherapy in children: LaMPO RCT

To demonstrate the efficacy of laser photobiomodulation (PBM) compared to that of placebo on severe oral mucositis (OM) in pediatric oncology patients. The primary objective was the reduction of OM grade (World Health Organization [WHO] scale) 7 days after starting PBM. Secondary objectives were reduction of pain, analgesic consumption, and incidence of side effects.

Diode Laser-assisted surgical therapy for early treatment of oral mucocele in a newborn patient: case report and procedures checklist.

Mucocele (also known as ranula or salivary gland mucous cyst) of the newborn is a lesion present on the intraoral cavity, with the potential to interfere with respiration and feeding. In the present report, a case of mucocele in a 4-month female patient has been described. As conventional surgery can be followed by several complications such as intraoperative bleeding, difficulties in wound healing, and maintenance of sterility during surgery, in the present case, the use of diode laser has been planned. A topic anesthesia with lidocaine gel was performed. A diode laser (810 nm wavelength, continuous wave mode, power output of 3 watt, and 0.4 mm diameter fiber optic) was set for excising the lesion. The tip was directed at an angle of 10 to 15°, moving around the base of the lesion with a circular motion. The procedure was completed in 3 minutes. The patient was visited with a follow-up of 2 weeks and 4 months after excision. The intraoral wound healed without complications, and no signs of infection or mass recurrence were noted. The histopathological examination confirmed the diagnosis of mucocele. On the basis of the results of the present case report, the use of diode laser can be easily performed also in a noncompliant newborn patient for successful excision of mucocele lesions, and checklist of clinical procedures has been described.

Combination of an optic system and Er:YAG laser in root canal preparation: study in vivo and in vitro

The effect of Er:YAG laser in debris removing after conventional root preparation was tested by optical system in vivo and scanning electron microscope in vitro. The root canal of fifty permanent molars was cleaned in vivo and Er:YAG laser treated. Flexiscope system was used to evaluate the efficacy of laser cleansing at the different stages of endodontic therapy. Forty permanent teeth, extracted for orthodontic or periodontal purposes, were treated in vitro using the same technique an instruments. The in vitro treated teeth were also examined under the SEM. The result of our investigation show an effective improvement of the cleansing of the endodontic surface from pulpal remaining and a smear layer after laser irradiation in vivo and in vitro. The use of Er:YAG laser in organic debris removing and the consequent optical system analysis of the quality of root preparation in vivo seem to be a reliable technique particularly useful in clinical application.