Mechanical evaluation of the influence of low-level laser therapy in secondary stability of implants in mice shinbones

Abstract

The present work evaluates mechanically the bone-implant attachment submitted or not to low-level laser therapy, with wavelength of 795 nm, in a continuous way, with power of 120 mW. The implant was placed in one of the shinbones of 24 mice, randomly distributed into two groups. The experimental group was submitted to six laser applications, divided into four points previously established, two lateral and two longitudinal, six times 8 J/cm2 with an interval of 2 days, totaling the dose of 48 J/cm2. The control group did not receive laser therapy. The interval between applications was 48 h and the irradiations began immediately after the end of the implant surgeries. The two groups were killed on the 14th day and a bone block of the area was removed where the implant was inserted. A torque machine was used to measure the torque needed for loosening the implants. A statistically significant difference was observed between the two groups. The experimental group presented larger difficulty for breaking up the implant interface with the bone block than the control group. It can be concluded that with the animal model and the protocol of irradiation present in this study, the laser therapy demonstrated capacity to increase the attachment bone implant.

Histomorphometric Assessment of the Influence of Low-Level Laser Therapy on Peri-Implant Tissue Healing in the Rabbit Mandible

“…Similar to findings described in previous studies, [8][9][10]13,14,18 our results showed enhanced bone growth around implants in all irradiated animals, although without significant difference from baseline values in all groups except E-20. This can certainly be attributed to the photobiomodulation action of LLLT.…”

“…[4][5][6][7] Experimental studies on the effect of LLLT on peri-implant bone healing have shown improved osseointegration and a shorter implant rehabilitation period. [8][9][10][11][12][13][14][15][16][17] The rabbit has been the preferred species for research on the process of osseointegration after LLLT. An advantage of rabbits over other animal models is that they are less aggressive, relatively inexpensive to purchase, and easy to house and maintain.…”

Effect of Three Different Protocols of Low-Level Laser Therapy on Thyroid Hormone Production After Dental Implant Placement in an Experimental Rabbit Model

“…These procedures would not be possible in rats or mice. 9,10,13,40 In accordance with the most recent literature, LLLT was delivered by an infrared laser [7][8][9][10][11][12][13][14][15][26][27][28]35,38 of 830 nm wavelength 7,10,[12][13][14][15] and 50 mW output power in two sites near the mandibular implant, in seven sessions 7,11,12,15 every 48 h, using three different doses. The use of a sham surgery and sham LLLT control group (C-I), as well as a baseline surgery but sham LLLT group (C-II), enabled us to isolate both the influence of baseline surgery and the systemic effects of LLLT.…”

“…Previous studies have evaluated the irradiation of extraction sockets, 3 modulation of skin wound healing, [4][5][6] regeneration of nervous tissue, 5 enhancement of peri-implant tissue repair after implant placement, 2,[7][8][9][10][11][12][13][14][15][16] and modulation of postoperative pain. 2,7,[17][18][19][20][21][22][23][24] Other in vivo and in vitro studies have reported the positive effects of LLLT on the repair process in animal models and tissue cultures.…”

“…2,7,[17][18][19][20][21][22][23][24] Other in vivo and in vitro studies have reported the positive effects of LLLT on the repair process in animal models and tissue cultures. 4,22,25 However, there are large variations in laser doses, [7][8][9][10][11][12][13][14][15]26 even though dose is considered an important parameter in laser therapy, 27 especially when some specific biomodulatory effects are expected.…”