title: Scanning electron microscopy and Fourier transformed infrared spectroscopy analysis of bone removal using Er:YAG and CO2 lasers.
abstract: BACKGROUND
  A thorough analysis of laser-ablated bone tissue is required before applying the technique to osseous surgery. In this study, we examine the morphological features and chemical composition of the bone surface after Er:YAG and CO2 lasers ablation.
  
  
  METHODS
  Six Wistar rats were used. An Er:YAG laser was used for ablation at an output energy of 100 mJ/pulse and a pulse rate of 10 Hz (1 W). Continuous CO2 laser irradiation was performed at an output energy of 1 W. Sites drilled using a conventional micromotor were used as controls. Analysis using scanning electron microscopy (SEM) and Fourier transformed infrared (FTIR) spectroscopy was performed.
  
  
  RESULTS
  Er:YAG laser ablation produced a groove with similar dimensions to that produced by bur drilling, whereas the CO2 laser produced only a charred line with minimal tissue removal. SEM observations revealed that the groove produced by the Er:YAG laser had well-defined edges and a smear layer-free surface with a characteristically rough appearance and with entrapped fibrin-like tissue. The melting and carbonization produced by the CO2 laser were not observed on sites irradiated by the Er:YAG laser. FTIR spectroscopy revealed that the chemical composition of the bone surface after Er:YAG laser ablation was much the same as that following bur drilling. The production of toxic substances that occurred after CO2 laser irradiation was not observed following Er:YAG laser irradiation or bur drilling.
  
  
  CONCLUSIONS
  These results suggest that the use of Er:YAG laser ablation may become an alternative method for oral and periodontal osseous surgery.
authors.affiliation: Department of Hard Tissue Engineering, Graduate School, Tokyo Medical and Dental University, Japan. sasaki.peri@tmd.ac.jp
authors.forename: Katia M
authors.initials: KM
authors.lastname: Sasaki
authors.forename: Akira
authors.initials: A
authors.lastname: Aoki
authors.forename: Shizuko
authors.initials: S
authors.lastname: Ichinose
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Yoshino
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yamada
authors.forename: Isao
authors.initials: I
authors.lastname: Ishikawa
mesh_terms: D000818:Animals; D002245:Carbon Dioxide; D004871:Erbium; D053685:Laser Therapy; D007834:Lasers / Q000009:adverse effects; D008854:Microscopy, Electron; D019647:Oral Surgical Procedures / Q000295:instrumentation*; D010294:Parietal Bone / Q000293:injuries / Q000601:surgery; D051381:Rats; D017208:Rats, Wistar; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002245:Carbon Dioxide; D004871:Erbium