title: Potential surface alteration effects of laser-assisted periodontal surgery on existing dental restorations.
abstract: OBJECTIVE
  Laser-assisted gingivectomies are performed in proximity to teeth, existing restorations, and implants. In case of accidental exposures, a detrimental surface defect may cause failure. Surface interactions should be evaluated for safety margin determination of certain laser-material combinations. The purpose of this in vitro study was to assess the microscopic and visible effects of CO2, Nd:YAG, and 810-nm diode laser irradiations on various dental materials and tooth tissue.
  
  
  METHODS
  Study samples were fabricated (10 x 7.5 mm irradiation surface area, 1 mm thickness) from eight material groups (amalgam, base metal, gold, palladium-silver, composite, ceramic, titanium, and extracted tooth slices). Laser irradiations were performed with CO2, Nd:YAG, and 810-nm diode lasers using the manufacturer's recommended settings for gingivectomy at a 45-degree angle for 30 seconds. Irradiated surfaces were evaluated under SEM at 200x and 1,000x magnifications. Standardized photographs were obtained using a camera mount system (10x high-definition macro lens). The SEM images and photographs were correlated to determine surface interactions.
  
  
  RESULTS
  Nd:YAG detrimentally affected all metallic materials and tooth structures. CO2 altered amalgam, gold, and palladium-silver slightly, whereas composite, ceramic, and tooth surfaces were detrimentally altered. The 810-nm diode altered amalgam, gold, titanium, palladium-silver, and composite but only gold and palladium-silver surfaces were barely traceable.
  
  
  CONCLUSIONS
  Within the limitations of this in vitro study, surface effects were all instant; therefore, even a short accidental exposure may be destructive in some laser-material combinations. During gingivectomies, CO2 near tooth-colored restorations and Nd:YAG near metallic restorations and implants should be used carefully. The 810-nm diode was found to be safer due to its reversible alterations in only some materials. Further in vivo studies are necessary to clinically apply the outcomes of this study.
authors.affiliation: Department of Cariology and Restorative Dentistry, Nova Southeastern University, Fort Lauderdale, Florida 33328, USA. kilinc@nova.edu
authors.forename: Evren
authors.initials: E
authors.lastname: Kilinc
authors.forename: James
authors.initials: J
authors.lastname: Rothrock
authors.forename: Erica
authors.initials: E
authors.lastname: Migliorati
authors.forename: Saulius
authors.initials: S
authors.lastname: Drukteinis
authors.forename: David M
authors.initials: DM
authors.lastname: Roshkind
authors.forename: Paul
authors.initials: P
authors.lastname: Bradley
mesh_terms: D003188:Composite Resins / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D003793:Dental Restoration, Permanent; D005890:Gingivectomy / Q000295:instrumentation*; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D053685:Laser Therapy / Q000295:instrumentation*; D007834:Lasers; D054020:Lasers, Gas / Q000627:therapeutic use; D054023:Lasers, Semiconductor / Q000627:therapeutic use; D053844:Lasers, Solid-State / Q000627:therapeutic use; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010165:Palladium / Q000737:chemistry; D010781:Photography; D012449:Safety; D012834:Silver / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D014070:Tooth / Q000473:pathology
chemical_list: D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials; D006047:Gold Alloys; D003776:Dental Porcelain; D012834:Silver; D010165:Palladium; D003723:Dental Amalgam; D014025:Titanium