Low level laser treatment (LLLT) is known for its photobiostimulatory and photobiomodulatory characteristics, which stimulate cell proliferation, increase cellular metabolism, and improve cellular ...regeneration. The objective of the present research was to assess the possible influence of infrared diode laser irradiation on the behaviour, attachment, and osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) seeded on different types of dental implants. Two distinct types of implants, one subjected to laser surface treatment and the other treated with acid etching, were longitudinally divided into two halves and submerged in six wells culture plates. Both implants were subjected to infrared diode laser treatment, and subsequently, the morphology and attachment of cells were examined using scanning electron microscopy (SEM) after 14 and 21 days. The behaviour of (hPDLSCs) towards two types of implants, when exposed to osteogenic medium and low-level laser therapy (LLLT), was assessed using quantitative real-time polymerase chain reaction to measure the expression of stemness markers and osteogenic markers. The scanning electron microscopy (SEM) demonstrated that the application of infrared diode laser irradiation substantially improved the attachment of cells to both types of implants. The stemness gene markers were significantly down regulated in cells seeded on both surfaces when challenged with osteogenic media in relation to control. At 14 days, early osteogenic markers, were upregulated, while late osteogenic markers, were downregulated in both challenged groups. At the 21-day mark, hPDLSCs seeded on an acid-etched implant exhibited increased expression of all osteogenic markers in response to stimulation with osteogenic media and infra-red diode laser, in contrast to hPDLSCs seeded on a laser surface treated implant under the same conditions. Finally, the findings of our research revealed that when subjected to infrared diode laser, human periodontal ligament stem cells cultured on both types of implants demonstrated improved cellular attachment and differentiation. This suggested that infrared diode laser enhanced the activity of the cells surrounding the implants. Hence, the use of infrared diode laser could be pivotal in improving and expediting the clinical osseointegration process around dental implants.
Background
The field of laser-based photochemical reactions receives a great promising for additional applications especially for targeting cells, pathogens, or molecules. Limited studies have ...investigated the impact of light-emitting diode on stem cell behavior. Thus, the aim of the present study was to assess the effect of diode laser irradiations on the proliferation of stem cells isolated from the human dental pulp. Isolation procedures were according to previously developed protocols for dental pulp stem cells (DPSCs). Low-level laser therapy irradiation (LLLT) was applied in two doses (0.5 J/cm
2
and 1 J/cm
2
for 20 s) into 96-well plates by the diode laser device (970 nm) through the fiber optic (SiroLaser fibers 320) at a distance from the opening of the wells to be accurate for equal distribution of the laser irradiation. To assess the proliferation capacity of the isolated stem cells, MTT assay was performed 24 h, 48 h, and 72 h.
Results
There was no significant difference among the different groups (gp 1 control, gp II dose 0.5 J/cm
2
, gp III dose 1 J/cm
2
) on day 1. While on day 2, the optical density of DPSCs subjected to dose 1 was found to be significantly higher than that of those subjected to dose 2. This was also demonstrated on day 3. It was also demonstrated that the proliferation of DPSCs subjected to dose 1 increased compared to that of DPSCs subjected to dose 2 from day 1 to day 2. There was a significant decrease in the cell number in both groups by 72 h.
Conclusion
In conclusion, the use of LLLT as a stimulatory factor for enhancing and proliferation of the stem cells is very promising.
Background: Titanium alloys are widely used in dental applications as they have good mechanical and biological properties. Implant failure is more likely to occur in inflammatory diseases related to ...acidic pH. The aim of the present study was to assess the effect of erbium chromium-doped yttrium-scandium-gallium-garnet 2780 nm laser surface treatment on the electrochemical behavior of titanium alloy (Ti-6Al-4V) at acidic pH.
Materials and Methods: In this in vitro study, a total of 20 discs of titanium alloy (Ti-6Al-4V) were used. First group, ten discs were irradiated with Er, Cr: YSGG laser which was operating in a normal room atmosphere and temperature at power 2W for 20 s at a constant distance of 0.5-1 mm with the laser system. The second group, ten discs untreated. The electrochemical behavior for both groups was investigated in simulated body fluid at pH 5.20 for up to 864 h at 192, 360, 696, and 864 h intervals using potentiodynamic polarization test and electrochemical impedance spectroscopy to evaluate the corrosion resistance.
Results: Laser-treated Ti-6Al-4V showed higher corrosion resistance at pH 5.20 compared to the untreated alloy. Immersion time affected the electrochemical behavior.
Conclusion: Er, Cr: YSGG laser could improve the corrosion resistance of Ti-6Al-4V at acidic pH.
Enamel demineralisation is an initial step of the serious dental problem including dental caries, white spot lesions and dental erosion.
Compare the effect of Er, Cr: YSGG (λ = 2780 nm) and ...nanosecond Nd: YAG (λ = 1064 nm) laser on enamel acid resistance.
Thirty non-carious human premolars, extracted for orthodontic reasons, were used. The experimental groups (n = 10 each group) were: Group I, untreated (control); Group II, Er, Cr: YSGG laser irradiation (0.75 W, 20 Hz, 140 μs, 10 s); Group III, nanosecond pulsed Nd: YAG laser irradiation (0.8 W, 10 Hz, 7 ns, 10 s). Scanning electron microscope and Energy Dispersive X-ray Spectroscopy (EDX) were used to assess acquired enamel resistance to PH cycling.
After subjecting the three experimental groups to PH cycling, scanning electron microscopic examination revealed irregular porous dissoluted enamel surface in group I. However, groups II and III demonstrated partially dissoluted enamel surface. EDX analysis demonstrated the lowest mean percentage decrease in calcium and phosphorus content in group II followed by group III, then the highest mean percentage decrease was observed in untreated group I. One-way ANOVA revealed significant differences (p < 0.0001) between the tested groups.
Both Er, Cr: YSSG and nanosecond Nd: YAG laser irradiation were able to improve the acid resistance of enamel. However, enamel surface treated with Er, Cr: YSSG laser showed the lowest mean percentage decrease of calcium and phosphorus (highest acid resistance).
Recent studies have demonstrated that low-level laser therapy (LLLT) can accelerate orthodontic tooth movement. However, there is still controversy about the optimum parameters that can cause ...acceleration. The present study was designed to examine two different doses of LLLT in the acceleration of orthodontic tooth movement and their effect on relapse.
An orthodontic appliance was designed to induce tooth movement on lower incisors of rabbits. The in-al-as diode laser was used to radiate different groups of rabbits according to a specific protocol. The amount of tooth movement was measured for 21 days, and then the orthodontic appliance was removed, and the relapse was measured till day 28.
The amount of tooth movement was significantly greater in the group with irradiation of low dose in comparison with the high dose group and the control group. The relapse was greatest in the group of low dose irradiation and least in the control group.
The findings suggest that LLLT with a low dose accelerate the orthodontic tooth movement while LLLT with a high dose was not able to have the same effect. LLLT had a reverse effect on relapse tendency; an increase in the relapse tendency was seen with low dose irradiation.
Objective: To evaluate and compare the influence of fiber post surface treatments (Er,Cr:YSGG laser sandblasting, and 9% hydrofluoric acid ) on surface roughness and morphology. Materials and ...Methods: A total of sixty fiber posts were used in this study. They were randomly divided into 4 groups according to surface treatment method into: Group I: control (no pretreatment), Group II: sandblasting (Al2O3), Group III: etch 9% hydroflouric acid etching , Group IV: Er,Cr:YSGG laser iradiation (2790 nm) .Group IV was further subdivided according to laser power to; subgroup A: 0.5W, subgroup B: 1W, subgroup C: 1.5W. Surface roughness (Ra) of the posts before and after surface treatment was measured using surface profilometer. The posts were examined under SEM for assessment of surface morphology. One-way ANOVA followed by Tukey post hoc test was used to compare between more than two groups in non-related samples. Results: There was statistical significant difference in the Ra value between the control group and all the tested groups (p<0.001). Sandblasting showed the highest significant mean Ra value while hydrofluoric acid had the lowest significant values. Conclusion: All the tested surface treatments method increased the surface roughness, and changed the surface morphology of the tested fiber posts.
Cardiovascular and renal complications define the outcomes of diabetic kidney transplant recipients (KTRs). The new diabetes medications have changed the management of diabetes. However, transplant ...physicians are still reluctant to use sodium-glucose cotransporter 2 inhibitors (SGLT2i) and Glucagon-like peptide-1 receptor agonists (GLP-1RA) post kidney transplantation due to fear of drug related complications and lack of established guidelines.
We collected 1-year follow-up data from records of 98 diabetic KTRs on SGLT2I, 41 on GLP- 1RA and 70 on standard-of-care medicines. Patients were more than 3 months post-transplant with a minimum estimated glomerular filtration rate (eGFR) of 25 ml/min/1.73 m
. Demographic data were similar except for a slightly lower HbA1c in the control group and higher albuminuria in SGLT2i group.
HbA1c dropped significantly by .4% in both SGLT2i and GLP-1RA compared to .05% in the control group. A significant decrease in BMI by .32 in SGLT2i and .34 in GLP-1RA was observed compared to an increase by .015 in control group. A tendency for better eGFR in study groups was observed but was non-significant except for the SGLT2i group with an eGFR above 90 (p = .0135). The usual dip in eGFR was observed in the SGLT2i group at 1-3 months. Albuminuria was significantly reduced in both study groups. Adverse events were minimal with comparable safety in all groups.
The use of SGLT2i and GLP-1RA appears to be effective and safe in diabetic KTRs with good outcomes. Randomized control trials are required to confirm these findings and establish guidelines.
PDF
