EFFEcts oF 980 nM HIGH-PoWEr dIodE LasEr IrradIatIon on EnaMEL MIcroHardnEss

Received for publication: Sep. 06, 2007. Revised: Sep. 21, 2007. rEZUMat 1 Department of Oral Rehabilitation and Dental Emergency, Faculty of Dentistry, Victor Babes University of Medicine and Pharmacy, Timisoara, 2 Department of Material Sciences and Thermal Treatments, Faculty of Mechanical Engineering, Polytechnic University, Timisoara, 3 Department of Dental Materials and Dental Technologies, Victor Babes University of Medicine and Pharmacy, Timisoara Correspondence to: Dr. Cosmin Balabuc, Department of Oral Rehabilitation & Dental Emergencies, 9 Revolutiei din 1989 Blvd, Timisoara, Tel. +40-256-221488 Email: [email protected] IntrodUctIon Although declining, dental caries are still the most prevalent disease during childhood and adolescence. Among artificial methods for the protection of EFFEcts oF 980 nM HIGH-PoWEr dIodE LasEr IrradIatIon on EnaMEL MIcroHardnEss Cosmin Balabuc1, Mariana Miron1, Camelia Demian2, Meda Negrutiu3, Laura Filip1, Carmen Todea1 Purpose: To evaluate the effects of high-power diode laser irradiation on enamel microhardness and to establish the best laser parameter settings in order to achieve an effective increase of microhardness. Materials and methods: 36 human single and multi-rooted teeth were used in this study. The roots were removed and the crowns were sectioned longitudinally in two halves, one representing the experimental sample and one the control sample. The samples were embedded in acrylic resin using cylindrical conformators in horizontal position leaving the flat surface outside. The flat surface of the experimental samples was irradiated using a 980 nm diode laser with an optical fiber diameter of 220 micrometers. The following parameters were used: power, ranging from 0.5 to 3 W; pulse width, ranging from 0.01 to 0.04 sec; exposure time of 5 seconds, resting time, ranging from 0.01 to 0.04 sec. Each microhardness measurement was performed three times on each sample. The enamel microhardness was measured using the Vickers method. The results were analyzed statistically using the MINITAB statistical software. Results: The statistical analysis demonstrated an increase of enamel microhardness in the experimental group, compared with the control group (p < 0.005) when using low energy densities. Moreover, the mathematical modeling allowed enamel microhardness computation when the parameters of the running system were known. Conclusion: The high-power diode laser is effective for increasing the enamel microhardness, preventing the occurrence of dental caries.