1,721,082 research outputs found
Clinicopathological Features Associated with Fluorescence Alteration: Analysis of 108 Oral Malignant and Potentially Malignant Lesions
No full textBackground: Several noninvasive diagnostic tools have been developed to aid the early detection of oral cancer and for evaluation before definitive biopsy. Among these, devices evaluating a tissues autofluorescence (AF) are emerging. In particular, the most well known of these is the VELscope® system (LED Medical Diagnostics, Inc., Barnaby, Canada), which emits a light of 400-460 nm. This study has been developed to describe the most relevant clinicopathological features associated with AF alterations in a set of patients with oral squamous cell carcinoma and potentially malignant disorders (PMDs). Materials and methods: Overall, 108 lesions from 60 patients with clinical diagnoses of potentially malignant oral disorders and carcinomas were included in the study. For each case, the following variables were recorded and compared with the AF pattern: (1) clinical appearance (white, red, and white/red); (2) histological diagnosis (no dysplasia, mild/moderate dysplasia, severe dysplasia/in situ carcinoma, invasive carcinoma, and verrucous carcinoma); and (3) clinicopathological diagnosis. Binomial logistic regression was performed to investigate whether clinical appearance and/or histological diagnosis were significant in determining the degree of AF. Results: Among the white lesions, 66% resulted in hyper-fluorescence, whereas the red lesions appeared hypo-fluorescent in 95.2% of cases. The AF was altered (both hypo-fluorescent and hyper-fluorescent) in 36% of lesions without dysplasia; in 75.9% of lesions with mild or moderate dysplasia and in the totality of the in situ, invasive, and verrucous carcinomas (p < 0.0001). With regard to the binomial logistic regression, variables were separately considered and both were extremely significant in determining the degree of AF. Conclusions: Promising evidence for the use of AF as an adjunctive tool to conventional oral examinations (COEs) has been demonstrated. However, although the sensitivity of AF examination associated with COE is very high, both the literature and this study agree to indicate a low specificity
The bleaching efficiency of KTP and diode 810 nm lasers on teeth stained with different substances: An in vitro study
No full textBackground and aims: The purpose of this study was to evaluate the bleaching efficiency of two different lasers (KTP and diode 810 nm) on teeth, randomly divided by means an Excel function (Microsoft Excel 2010 "Fx causale") and stored in physiological solution, that were previously stained with different substances commonly considered as a cause of tooth discoloration, such as coffee, tea and red fruits and to investigate the role of laser irradiation in an experimental model, during the dental bleaching process. Methods: Three groups of 45 bovine teeth were created and immersed for one week in a solution of tea, coffee or red fruits respectively. Each group was divided into three sub-groups of fifteen teeth. One was bleached with a 30% hydrogen peroxide gel for 30 min only as control, another 15 teeth group was bleached with the gel plus 810 nm diode laser irradiation and the last group was bleached with the gel plus KTP irradiation. The lasers were applied in three cycles of 30 sec each with a power of 1.5 W localized on a 10 mm spot on the teeth. The temperature of the gel was checked during the bleaching procedure using a thermometer and the colour of each tooth was measured by a spectrophotometer. Results: Statistical analysis of the collected data was performed using Graph Pad Prism, version 6.01 software, Kruskal-Wallis test and Dunn's multiple comparison test and Mann-Whitney test. P value 0.05 not significant (ns). By these tests diode laser was effective only at bleaching teeth stained with coffee meanwhile the KTP laser was efficient at bleaching teeth with coffee, tea and red fruits stains. Conclusion: This study suggests that a relation between the laser wavelength and the type of staining on the dental enamel and the efficacy of the whitening treatment exists. © 2014 JMLL, Tokyo, Japan
Low-Level Laser Therapy in odontostomatologia: istruzioni per l'uso
No full textObjectives. The purpose of this paper is to demonstrate the advantages of using Low-Level Laser Therapy (LLLT) in dentistry. Materials and methods. This work describes mechanisms of action, optimal parameters, possible contraindications to this type of treatment and its main indications. Results. In vitro and in vivo studies on animals and humans have shown the efficacy of LLLT mainly in stimulating healing processes, fostering anti-inflammatory mechanisms and controlling pain: these three effects have validated the application of LLLT in different fields of dentistry. Conclusions. LLLT is an undoubtedly great opportunity for applications in dentistry, as, due to its limited contraindications, it may be considered free of side effects: in fact, thanks to the low parameters used, there are neither tissue destruction, nor other possible dangers linked to higher powers
Laser Applications and Autofluorescence
No full textThe diagnostic pathway for oral suspicious lesions usually starts with the clinical examination based on inspection and palpation of the oral mucosa. Such a phase is strongly related to the experience of the operator. Moreover, oral epithelial dysplasia and early oral carcinomas may already be present within areas of macroscopically intact oral mucosa. A great interest for techniques potentially improving the diagnostic accuracy has developed in several fields of surgical oncology in order to increase the specificity and sensitivity of the conventional diagnostic pathway. The development of noninvasive methods for real-time screening of neoplastic changes in oral cavity may be associated with the improvement of patients' quality of life and survival rate. The analysis of tissue autofluorescence (AF) for improving sensitivity and specificity in cancer diagnosis has been proposed for different organs, including colon, lung, cervix, and esophagus. Particularly, there are several evidences supporting the effectiveness of this technique in head and neck cancer diagnosis. Autofluorescence shows high specificity and sensitivity for oral cancer and precancerous lesions: 72.4% and 63.79%, respectively. It can also provide valuable information for diagnosis, for planning of margin resection in surgical excision, and for monitoring the therapeutic response during follow-up. Direct visual fluorescence examination (DVFE) is based on the action of irradiation of specific wavelengths, between 375 and 440 nm, which excites some natural fluorochromes which show fluorescence in the range of the green color. The analysis of the lesions with AF tools must be performed in a dark environment to avoid the interference of white light wavelengths and to improve the quality of recorded images. Healthy oral mucosa emits fluorescence, detectable as green light. Cell and tissues within dysplastic and malignant lesions display modifications of the amount, distribution, and chemical-physical properties of the endogenous fluorophores. This results in an autofluorescence pattern variation that can be potentially used at diagnostic level. Loss of autofluorescence (LAF) seems to increase in correspondence to the progression of dysplasia, and altered tissue appears dark (brown to black). LAF in dysplasia and carcinoma seems to be connected to different mechanisms, such as altered metabolic activity of dysplastic keratinocytes, altered structure of subepithelial collagen, and absorbance of light by increased blood circulation due to inflammatory phenomena in dysplastic tissue and cancer. AF can be used for guiding incisional biopsy and in the excision to identify the resection margins
COVID-19 diffusion and its impact on dental practice in distant countries with similar ethnic background
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