Evaluation of thermal damage in dental implants after irradiation with 980nm diode laser. An in vitro study

Abstract

Purpose: The aim of this study was to analyze the thermal damage in dental implants after irradiations with a 980nm diode laser,
normally used for the decontamination.
Material and Methods: Five Titanium Plasma Sprayed dental implants were irradiated with a 980nm diode laser at different
parameters. Temperature increase on implant surface was evaluated by a Mid-Wavelength Infrared thermal-camera (Merlin®, FLIR,
USA). Temperature increase (ΔT) was compared to environmental temperature (27°C) and recorded in three points: “A” (laser
spot), “B” (3mm apically to the laser spot) and “C” (2mm horizontally to the laser spot). Finally, a morphological evaluation at
optical stereomicroscopy was performed.
Results: When 0.6W power was applied, a moderate increase of temperature in point A (5.5°C-15.0°C), a slight increase in point
B (0.1°C-6.2°C) and point C (0.1°C-5.7°C), were registered after 30” of irradiation. In the samples treated at 6W, in “point A”
an impressive ΔT increase was immediately recorded (over 70°C). In “point B” was recorded a slight ΔT after 2 sec. irradiation
(range 2.3°C-6.0°C), a moderate ΔT after 4 sec. irradiation (16.4°C) and a consistent ΔT after 8-10 sec. irradiation (range
36.6°C-46.2°C). In “point C” ΔT values were very similar to those collected in “point B”. Optical stereomicroscopy examination
at a magnification of 32x did not show any surface alteration or damage after whichever laser irradiation independently from
irradiation time and power output .
Conclusions: 980nm diode laser, used at controlled parameters, can be used in the decontamination of dental implants, without
causing any thermal damage or increase.