In vivo analysis of low-power laser effects irradiation at stimulation of reactive dentine

Abstract

Investigate and compare the amount of reactive dentine formation after application of two different flunkies of low level laser. Rapid formation of reparative dentine is convenient, mainly when pulp is almost exposed. Several studies have shown that the use of correct fluency of low level laser can enhance cellular proliferation and seems to stimulate the production of reactive dentine. Using 780 nm infrared laser, twelve swine were tried using 3 teeth each. Three treatments groups were classified: GI -control group: without irradiation; GII -irradiation using fluency of 12.8 J/cm 2 ; and, GIII -irradiation using fluency of 89.7 J/cm 2 . Laser irradiation was performed on dentine (class V standardized) of the upper and lower incisors and on the apex of each tooth for 3 consecutive times, with a 72 h break of time. Histological studies were conducted at 4 distinct periods of time (8, 14, 28, and 52 days). GII showed increase on the formation of reparative dentine with significant difference (p < 0.01) between GI and GIII. Comparison between GI and GIII shows that there was no significant difference at 4 periods of time. After 52 days, the amount of reparative dentine was similar between GI, GII, and GIII. The dentinal matrix formation equal primary dentine occurred earlier in the GIII, GII, and GI, respectively. Our results suggest that into a twenty eight days period, the 12.8 J/cm 2 laser group was able to positively stimulate it, accelerating the odontoblast process and after 52 days, the formation of reactive dentine seems stabilized. C OLHistological results from GIII, considering fourteen days of period of time to evaluation

Nutritional stress enhances cell viability of odontoblastlike cells subjected to low level laser irradiation

“…The LLL interacts with different types of tissues and LLL therapy (LLLT) is known to cause varied reactions and modulate several biological processes. It has been demonstrated that the photo-stimulation mediated by the LLLT, in addition to increase ATP synthesis [6], produces an analgesic effect [7][8][9] and stimulates cell division [10], accelerating tissue healing [11][12][13]. Some specific laser types also have the capacity to stimulate the synthesis and deposition of collagen matrix by fibroblasts [14][15][16], and the increase of mitochondrial activity and cell metabolism [8] and proliferation [12].…”

Red LED Photobiomodulates the Metabolic Activity of Odontoblast-Like Cells

“…The biostimulative effect induced by low level phototherapy on the repair capacity of the dentin-pulp complex has been demonstrated in vitro and in vivo (3,9,18,19). This effect is characterized by the increased cell proliferation and mineralized matrix production.…”

In vitro effect of Q-switched Nd:YAG laser exposure on morphology, hydroxyapatite composition and microhardness properties of human dentin

“…Laser has firmly established itself as an indispensable tool for various applications such as in micromachining and medical surgery. [1][2][3][4][5] Dental laser based on Nd:YAG laser is used in dentistry area for therapy supporting on soft tissues in 1980. Recently, laser development is used to save application for dental hard tissues therapy.…”

“…In dentistry, laser is used for supporting therapy on soft tissues and evaluating dental enamel, caries morphology, dentine resistance, and dental plaque composition. 1,[4][5][6] Among the most used laser systems in dentistry relies one Nd:YAG laser with a wavelength of 1064 nm assuring the specific characteristic of presenting affinity with pigmented tissues, which particularly makes it selective for carious tissues.…”

“…4,5 Nd:YAG laser irradiated was used to evaluate the dental enamel caries morphology through SEM images, 1 dental plaque composition of human enamel, 4 surface dentin modification, 8,9 phototermal and optical breakdown production. 10 The aim of this in vitro study was to investigate the effect of a Q-switched Nd:YAG laser irradiated to healthy human dentin (without caries and plaque) by regulating the voltage oscillator ranging from 660 to 740 Volt, with the variataion of power density are 13.9 J/cm 2 , 21.2 J/cm 2 and 41.7 J/cm 2 .…”