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The removal of porcelain veneers using Er:YAG lasers has not been previously described in the scientific literature. This
study was designed to systematically investigate the efficacy of an Er:YAG laser on veneer debonding without damaging
the underlying tooth structure, as well as preserving a new or misplaced veneer.
Initially, Fourier Transform Infrared Spectroscopy (FTIR) was used on flat porcelain veneer samples (IPS Empress
Esthetic; Ivoclar Vivadent, Amherst, NY) to assess which infrared laser wavelengths are transmitted through the veneer.
Additionally, FTIR spectra from a veneer bonding cement (RelyX Veneer Cement A1; 3M ESPE, St. Paul, MN) were
obtained. While the veneer material showed no characteristic water absorption bands in the FTIR, the bonding cement
has a broad H2O/OH absorption band coinciding with the ER:YAG laser emission wavelength. Consequently Er:YAG
laser energy transmission through different veneer thicknesses was measured. The porcelain veneers transmitted
11 - 18 % of the incident Er:YAG laser energy depending on their thicknesses (Er:YAG laser: LiteTouch by Syneron;
wavelength 2,940 nm, 10 Hz repetition rate, pulse duration 100 μs at 133 mJ/pulse; straight sapphire tip 1,100 μm
diameter; Syneron, Yokneam, Israel). Initial signs of cement ablation occurred at approximately 1.8 - 4.0 J/cm2. This can be achieved by irradiating through the veneer with the fiber tip positioned at a distance of 3-6 mm from the veneer
surface, and operating the Er:YAG laser with 133 mJ output energy.
All eleven veneers bonded on extracted anterior incisor teeth were easily removed using the Er:YAG laser. The removal
occurred without damaging underlying tooth structure as verified by light microscopic investigation (Incident Light
Microscope Olympus B 50, Micropublisher RTV 3.3 MP, Image Pro software, Olympus). The debonding mainly
occurred at the cement/veneer interface. When the samples were stored in saline solution for 5 days and/or an air-waterspray
was used during irradiation, there was a high chance that the veneer would fractured during debonding. However if
samples were not stored in water and only air spray was used, 75% of the veneers could be removed without any
fracture.
The use of an Er:YAG laser can be effective in not only debonding porcelain veneers and preserving tooth structure, but
also in maintaining veneer integrity.
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