Evaluation of bone healing following Er:YAG laser ablation in rat calvaria compared with bur drilling. Issue 3 (9th December 2018)

• Record Type: Journal Article
• Authors: Ohsugi, Yujin; Aoki, Akira; Mizutani, Koji; Katagiri, Sayaka; Komaki, Motohiro; Noda, Masahiro; Takagi, Toru; Kakizaki, Sho; Meinzer, Walter; Izumi, Yuichi
• Is Part Of: Journal of biophotonics. Volume 12:Issue 3(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-12-09
• Subjects: bone -- bone ablation -- Er:YAG laser -- microarray -- micro‐CT -- wound healing; Photonics -- Periodicals; Optical materials -- Periodicals; Optics -- Periodicals; Medical instruments and apparatus -- Periodicals; 621.3605
• DOI: 10.1002/jbio.201800245
• Languages: English
• ISSNs: 1864-063X

Abstract

Abstract : The Er:YAG laser is currently used for bone ablation. However, the effect of Er:YAG laser irradiation on bone healing remains unclear. The aim of this study was to investigate bone healing following ablation by laser irradiation as compared with bur drilling. Rat calvarial bone was ablated using Er:YAG laser or bur with water coolant. Er:YAG laser effectively ablated bone without major thermal changes. In vivo micro‐computed tomography analysis revealed that laser irradiation showed significantly higher bone repair ratios than bur drilling. Scanning electron microscope analysis showed more fibrin deposition on laser‐ablated bone surfaces. Microarray analysis followed by gene set enrichment analysis revealed that IL6/JAK/STAT3 signaling and inflammatory response gene sets were enriched in bur‐drilled bone at 6 hours, whereas the E2F targets gene set was enriched in laser‐irradiated bone. Additionally, Hspa1a and Dmp1 expressions were increased and Sost expression was decreased in laser‐irradiated bone compared with bur‐drilled bone. In granulation tissue formed after laser ablation, Alpl and Gblap expressions increased compared to bur‐drilled site. Immunohistochemistry showed that osteocalcin‐positive area was increased in the laser‐ablated site. These results suggest that Er:YAG laser might accelerate early new bone formation with advantageous surface changes and cellular responses for wound healing, compared with bur‐drilling. Abstract : Erbium lasers, as well as conventional burs, are currently being used for bone ablation. In this study, Er:YAG laser ablation sites showed significantly higher bone repair ratios than bur‐drilled sites. A heatmap demonstrates that gene expressions related to heat shock proteins ( Hspa1a and Hsph1 ), inflammation ( Cxcl6 and Mmp3 ) and osteocytes ( Dmp1 and Sost ) are dramatically different between laser‐irradiated and bur‐drilled bone.