A Pilot Study Of Treating Dentine Hypersensitivity By Er.Cr:YSGG Laser

ObjectiveTo explore the effect of sealing dentinal tubules by Er.Cr:YSGG, and to try to discuss the mechanics of sealing dentinal tubules and evaluate the laser' s application for desensitizing dentine hypersensitivity .Methods1 35 freshly extracted human premolars and molars were selected. Their dentin was exposed and made into 70 dentin cubics with high-speed hand piece .whose dimenshion was 2 × 2 × 2 mm~3. Thesedentin cubics were randomly divided into timly group and wearing-out group after being prepared for hypersensitivity model by 5% acetic acid.Each group included 35 dentin cubics , five of which selected as negative control dentin cubics without being treated , the others were treated with Gluma desensitizer or Er. Cr:YSGG laser with the energy of 0. 5, 1. 5, 2. 5, 3. 5 or 4. 5W. Then, the timely group was observed by means of a scanning electron microscope, while, the wearing-out group have been yet treated through the imitation of brushing tooth before did that.2 15 freshly extracted human premolars and molars were selected. Their dentin was exposed and made into 30 dentin cubics with high-speed hand piece , whose dimenshion was 2×2×2 mm~3. These dentin cubics were randomly divided into a control group and a study group after being prepared for hypersensitivity model by 5% acetic acid. The former group included 5 dentin cubics , which have been selected as negative control dentin cubics without being treated , the others belonging to the study group, which were irradiated by Er. Cr:YSGG laser with the energy of 0.5,1.5,2.5,3.5 or 4. 5W. Then, the both groups were observed by means of horiba EX350 to test the changing of composed elements.3 30 freshly extracted human molars were selected. Their dentin was exposed and made into 30 dentin cubics with high-speed hand piece .whose dimenshion was 6X5X0. 5 mm~3. These dentin cubics were randomly divided into a control group and a study group after being prepared for hypersensitivity model by 5% acetic acid, the former group included 5 dentin cubics , which have been selected as negative control dentin cubics without being treated , the others were irradiated by Er. Cr:YSGG with the energy of 0.5,1.5,2.5,3.5 or4. 5W. Then, the both groups were observed by means of D / max - 2500 Pc.Result1 Er. Cr:YSGG laser could seal dentinal tubules well. More high the export energy, more obvious the result, dentin tubules could not be observed after irradiation by Er. Cr:YSGG laser with 4.5W.2 Dentin tubules of groups treated with Er. Cr:YSGG laser keep original appearance, while, dentin tubules of groups treated with Gluma appear again after the brushing-test.3 Weight percentages of calcium and phosphorus rise in groups treated with Er. Cr:YSGG laser and rising tendency keeps the pace with the export energy of Er. Cr:YSGG laser.4 No signifcant difference between the two groups could be observed through the D / max - 2500 Pc.Conclusion1 The effect of sealing dentin tubules by Er. Cr:YSGG laser is superior to that by Gluma, permanently and durably.2 The higher export energy of Er. Cr:YSGG laser, the more effectively sealing dentin tubules.3 Er. Cr:YSGG laser should be applicated deeply, for it has many advantages and operates easily.4 The possible mechanics of sealing dentin tubules by Er. Cr:YSGG laser could be through melting the dentin, or,that the dentin debris stuff dentin tubules.