Morphological alterations of radicular dentine pretreated with different irrigating solutions and irradiated with 980‐nm diode laser

Abstract

The tested parameters of 980-nm diode laser promoted similar alterations on dentine morphology, dependent to the type of surface pretreatment.

Microhardness of Radicular Dentin Treated with 980-nm Diode Laser and Different Irrigant Solutions

“…This can be attributed to the thermal effect caused by laser energy, which changes the dentin structure. 9,10,14,15 The action mechanism of the 980-nm diode laser is likely to be similar to that of the 1064-nm Nd:YAG laser, because both are located in the nearinfrared region of the electromagnetic spectrum. 11 In these wavelength bands, some energy is absorbed by dentin mineral content, such as carbonate and phosphate, resulting in crystalline arrangement and melting.…”

“…11 In these wavelength bands, some energy is absorbed by dentin mineral content, such as carbonate and phosphate, resulting in crystalline arrangement and melting. 10 Diode lasers could cause damage to the root surface, and some of its effects have not yet been completely determined, making it relevant to determine parameters in vitro before using it in clinical practice. The parameters of this study were selected based on the study of Alfredo et al 7 These authors verified that the application of 980-nm diode laser in root canal, for 20 sec, at 1.5 and 3.0 W with 100 Hz did not result in temperature rises > 10°C 16 , which makes it feasible to use safely in endodontic therapy.…”

“…3 The 980-nm diode laser transmits energy through thin flexible fibers, compatible with the dimensions and curved shapes of root canals. [3][4][5][6][7][8][9][10] Diode laser wavelengths have good penetration potential, high absorption peaks in melanin and hemoglobin, and low interaction with water and hydroxyapatite. 5,6 The penetration capability of diode lasers (810-980 nm) is 10,000 times greater than that of Er:YAG, 11 and may reduce the number of microorganisms up to 500 lm in depth within the dentinal tubules.…”

“…Morphological alterations in dentin irradiated with diode laser can be observed by scanning electron microscope, 5,8,10 and depend mainly on the parameters of the lasers such as output power, frequency, and application mode. This is because these parameters are directly related to the increase in temperature in the dental tissues.…”

Investigations of radicular dentin permeability and ultrastructural changes after irradiation with Er,Cr:YSGG laser and dual wavelength (2780 and 940 nm) laser

“…This fact would explain the confinement of Er,Cr:YSGG laser in the main channel. On the contrary, 940 nm diode laser is predominantly scattered through the inhomogeneous dentin structure rather than absorption which is neither happened in water nor in hydroxyapatite [26,12]. Consequently, a high degree of decontamination can be expected, even in deep layers of dentin [11].…”