title: Chemical analysis and surface morphology of enamel and dentin following 9.6mu CO2 laser irradiation versus high speed drilling.
abstract: OBJECTIVE
  The purpose of the present in vitro study was to determine whether there is a change in the chemical composition and surface morphology of enamel and dentin following 9.6mu CO2 laser irradiation and high-speed drilling.
  
  
  METHODS
  Ten permanent, non-carious, young premolars, extracted for orthodontic reasons, were selected. The crowns were separated longitudinally into two equal parts at their mesiodistal axis. Two areas on the inner enamel surface of each specimen and two on the dentinal surface were selected. A high-speed drill and 9.6mu CO2 laser irradiation were applied to the selected enamel and dentinal areas. A random area on the unlased enamel and on the unlased dentin of each specimen served as controls. The morphology of the specimens was evaluated using scanning electron microscopy. Calcium, phosphorus and oxygen levels were measured using an energy dispersive spectrometer.
  
  
  RESULTS
  Mineral analysis revealed no significant difference in the mineral content of the enamel and dentin after laser irradiation or high speed drilling versus the control. Use of the high-speed drill on enamel and dentin resulted in very clear cavity margins, with characteristic grooves, whereas laser irradiation of enamel and dentin did not produce clear margins and the floor of the cavity displayed an irregular surface.
  
  
  CONCLUSIONS
  The 9.6mu CO2 laser appears to be a promising tool in the clinical setting. However, further investigation is indicated to ensure maximum effectiveness.
authors.affiliation: Department of Endodontics, Hebrew University-Hadassah School of Dental Medicine, Israel.
authors.forename: Joshua
authors.initials: J
authors.lastname: Moshonov
authors.forename: Adam
authors.initials: A
authors.lastname: Stabholz
authors.forename: Rita
authors.initials: R
authors.lastname: Bar-Hilel
authors.forename: Benjamin
authors.initials: B
authors.lastname: Peretz
mesh_terms: D000704:Analysis of Variance; D002118:Calcium / Q000032:analysis; D003737:Dental Cavity Preparation / Q000295:instrumentation / Q000379:methods*; D003743:Dental Enamel / Q000737:chemistry; D003755:Dental High-Speed Technique; D003804:Dentin / Q000737:chemistry; D006801:Humans; D007834:Lasers; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D013052:Spectrometry, X-Ray Emission; D018709:Statistics, Nonparametric; D013499:Surface Properties
chemical_list: D010758:Phosphorus; D010100:Oxygen; D002118:Calcium