A study on the change of root surface irradiated by Er:YAG laser

Er:YAG laser를 조사한 치근면의 변화에 관한 연구

  • Lee, Sang-Hyun (Dept. of Periodontology, College of Dentistry. Dental Science Research Institute, Chonnam National University) ;
  • Kim, Young-Jun (Dept. of Periodontology, College of Dentistry. Dental Science Research Institute, Chonnam National University) ;
  • Chung, Hyun-Ju (Dept. of Periodontology, College of Dentistry. Dental Science Research Institute, Chonnam National University)
  • 이상현 (전남대학교 치과대학 치주과학교실, 치의학 연구소) ;
  • 김영준 (전남대학교 치과대학 치주과학교실, 치의학 연구소) ;
  • 정현주 (전남대학교 치과대학 치주과학교실, 치의학 연구소)
  • Published : 2002.06.30

Abstract

This study was performed to evaluate the usability of Er:YAG laser for periodontal therapy. Forty dental root slabs ($5{\times}5{\times}2mm^3$) were prepared from human periodontally diseased extracted teeth and grouped into 4 groups: 1) control (root planing only), 2) root planing and irradiated with laser at 30mJ, 3) root planing and irradiated with laser at 60mJ, and 4) root planing and irradiated with laser at 100mJ. The root slabs were embedded in resin block before laser treatment. Er:YAG laser was irradiated under water irrigation with the tip held perpendicular to the root surface in contact mode. After Er:YAG laser irradiation or planing on the root surface, morphological changes have been observed under SEM, and the micro-hardness and Ca/P ratio were compared. 1. In the Control group, the root surface showed the directional change caused by root planing instrumentation, and the presence of smear layer, and no exposure of dentinal tubule was observed. Laser irradiated group showed surface changes with rough dentin surface of niche and depression and dentinal tubule exposure by the elimination of smear layer. 2. The micro-hardness of root surface in the laser irradiated group was higher than the control group. The higher energy output was applied, the higher micro-hardness on root surface was resulted. 3. The higher energy output was applied, the higher Ca/P ratio was observed. The higher Ca/P ratio in 60mJ group and 100mJ group was statistically significantly compared to the control group and the 30mJ group. These results suggest that Er:YAG laser irradiation on the periodontally diseased root surface could remove smear layer and increase the micro-hardness on root surface and Ca/P ratio which contribute to enhance the acid resistance of periodontally treated root surface.

Keywords

References

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