OOOO ABSTRACTS

Volume 117, Number 5 Abstracts e389

areas of bony necrosis and sequestra. Also noted were punched-out lesions along the mandibular rami bilaterally.

Conclusions: The importance of developing a completemedical history and obtaining a medical consultation with rele-vant practitioners cannot be overemphasized. In addition, properpatient education and dental evaluation before and duringbisphosphonate use should be considered as one of the importantprotocols in patient treatment.

OI0430 DIFFUSE REFLECTANCE SPECTROSCOPY FORMAPPING ORAL MUCOSAL TISSUE Omar Hamadah,Razan Hafez, Wesam Bachir, Oral Medicine department,Dental Faculty and Higher Institute for Laser Research andApplications, Damascus, Syria

Objectives: To evaluate the ability of diffuse reflectancespectroscopy (DRS) to differentiate between normal oral mucosalregions according to their histologic nature in the oral cavity.

Methods: A total of 21 healthy patients aged 21 to 75years were diagnosed as healthy and probed with a portableDRS system. Diffuse reflectance spectra were recorded in vivoin the range of 450-650 nm. In this study, 3 oral mucosal areaswere considered, including the masticatory mucosa, liningmucosa, and specialized mucosa. Spectral features based onspectral intensity ratios were determined at 5 specific wave-lengths (512, 540, 558, 575, and 620 nm). The 3 studied groupsrepresenting different anatomic regions in the oral cavity werecompared using analysis of variance and post hoc Bonferronitest.

Results: There was a significant difference in mean diffusespectral ratios (512/540, 512/558, 512/575, 54/575, 558/620, 575/620) between groups (P < .05). The post hoc Bonferroni testdetected significant difference in the aforementioned spectral ra-tios between the masticatory mucosa group and the lining mucosagroup (P < .05) and between the masticatory mucosa group andthe specialized mucosa group (P ¼ .024 at ratio 558/620 and P ¼.024 at ratio 575/620). Significant difference in mean spectralratios was also found between the lining mucosa group and thespecialized mucosa group (P ¼ .022 at ratio 512/558 and P ¼.038 at ratio 512/575).

Conclusions: The results indicated the feasibility of DRS asan optical tool for differentiation of oral epithelial tissue. Thestudy enabled the creation of a DRS databank of normal oralmucosal tissue with specific spectral features that may be mappedto enhance the discrimination of oral tissue. The findings could beused for guiding the examiner on the histologic nature of oralmucosa and identifying early changes in oral tissues.

OI0309 NEW FRONTIERS FOR RADIOTHERAPY-INDUCED ORAL MUCOSITIS AND RADIODERMATITISMANAGEMENT Margherita Gobbo, Giulia Ottaviani,Serena Zacchigna, Roberto Di Lenarda, Matteo Biasotto,Dental Science Department, Division of Oral Medicine andPathology, Trieste, Italy

Objectives: Oral mucositis (OM) and radiodermatitis(RD) are serious side effects of radiotherapy (RT), often lead-ing to RT suspension, need for analgesics, and enteral/paren-teral nutrition. Laser therapy is a novel therapy used forprevention and management of OM. This prospective studyaimed to explore the beneficial effect of class IV high-powerlaser therapy (HPLT) on RT-induced OM, but it also proposedan innovative strategy to manage RD in patients with breastcancer.

Methods: A group of 53 patients with cancer affected byOM, during or after RT with or without chemotherapy, weretreated with HPLT during 4 consecutive days (970 nm, 5 W(50%), 35-6000 Hz, 230 s). Assessment of OM (World HealthOrganization [WHO] scale), pain (visual analog scale [VAS]),functional ability, subjective parameters, site/severity of ulcera-tions, and erythema were recorded on days 1 to 4 and at follow-upvisits on days 7, 14, and 21. Friedmann, McNemar, and Wilcoxontests (SPSS, version 13.0) were used appropriately. 17 patientswith breast cancer affected by RD were treated by HPLT (6sessions during 2 weeks) and monitored during 3 weeks (days 19,26, 33) for OM grade, discomfort, and itching.

Results: Progressive improvement of WHO score from day7 onward, and of VAS from day 2 onward (P < .001), wasregistered. All patients’ functional capacity improved on day 4 (P< .05). All subjective parameters improved on day 14 (P < .001),and voice improved on day 21 (P < .001). Ulceration dimensionsand erythema severity significantly decreased over time in all oralsites examined (P < .05). In the same way, HPLT provedbeneficial in the amelioration of RD for all the parametersconsidered (P < .001).

Conclusions: Regardless of OM grade/site and of kind/siteof tumor, HPLT seemed effective in healing OM. Remarkably,we can hypothesize its beneficial role in the management of RD.In both cases, effective treatment could improve quality of lifethrough a safe, easy, innovative approach.

OI0311 CLASS IV LASER BIOSTIMULATION AND TU-MOR ANGIOGENESIS Giulia Ottaviani, Margherita Gobbo,Rossana Bussani, Serena Zacchigna, Roberto Di Lenarda,Biasotto Matteo, Division of Oral Medicine and Pathology,Dental Science Department, University of Trieste, Trieste, Italy

Objectives: Given that angiogenesis is considered one ofthe main effects of laser biostimulation, although it mayrepresent an undesired risk for patients bearing a tumor of theoral cavity, we used a murine carcinogenesis model to verifyits effect on tumor-associated angiogenesis, and subsequenttumor growth.

Methods: In vivo study: Oral cancerous lesions wereinduced in a total of 40 mice through 4-nitroquinoline 1-oxide(4-NQO) diluted in drinking water. After 16 weeks, all ani-mals’ cages were reverted to regular water. Mucosal changeswere documented twice a week and oral cavity examinationwas performed until week 22. During the 17th week, the tumorarea was directly irradiated with class IV diode laser in 20animals for 4 consecutive days. Animals were euthanized fortissue retrieval. Histopathologic examinations were performed.Subsequently, the role of laser therapy on tumor angiogenesiswas evaluated by perfusing tumors with fluorescent NanoFluo-spheres, followed by quantitative evaluation of the fluorescenceand 3-dimensional reconstruction of the vascular network byconfocal microscopy. In vitro study: Human coronary arterysmooth muscle cells were cultured in SmcGM medium andirradiated with the same class IV diode laser, specificallydesigned to provide a uniform irradiation to a multiwell plate(96 wells). Cultured cells were exposed to different laser pro-tocols. At 2, 6, and 24 hours after laser irradiation, the ATPcontent was measured using the ATPlite Luminescence AssaySystem.

Results: Neither tumor growth nor tumor angiogenesisincreased in the laser-treated group; laser seemed to isolate tu-mors, decreasing dysplastic areas, instead. Moreover, laser-