Two-layer film as a laser soldering biomaterial.

BACKGROUND AND OBJECTIVES: A two-layer solder was developed to weld at low laser intensity and to provide a new method of measuring solder-tissue temperature. STUDY DESIGN/MATERIALS AND METHODS: A film solder consisted of a white layer (bovine serum albumin (BSA) and distilled water) and a black layer (BSA, carbon black (CB), and distilled water). This two-layer solder was used with a diode laser to weld sections of dog small intestine (lambda = 810 nm, power = 200 +/- 20 mW, radiation dose = 18 +/- 1 J/mg). Sections of intestine were welded only with one-layer black solders as control group. The temperature difference between the external solder surface and the tissue-solder interface was evaluated during welding. RESULTS: The two-layer solder performed welds as strong as the one-layer solder ( approximately 0.12 N) but with less laser intensity on the black layer. The temperature difference between the external surface of the solder and the solder-tissue interface was significantly less for the two-layer solder than for the one-layer solder ( approximately 6 degrees C and approximately 15 degrees C, respectively; P < 0.05). CONCLUSIONS: The two-layer solder appeared to be more efficient at soldering biomaterials than the one-layer solder. Furthermore, the heat diffusion from the black midplane of the two-layer solder decreased the difference in temperature recorded on the solder external surface and on the solder-tissue interface.     

Inhibitory effects of low-level laser therapy on skin-flap survival in a rat model

BACKGROUND:Although several studies have demonstrated the effects of low-level laser therapy (LLLT) on skin flap viability, the role of higher doses has been poorly investigated.OBJECTIVE:To investigate the inhibitory effect of the LLLT (λ=670 nm) on the viability of random skin flaps in a rat model using an irradiation energy of 2.79 J at each point.METHODS:Sixteen Wistar rats were randomly assigned into two groups: sham laser irradiation (n=8); and active laser irradiation (n=8). Animals in the active laser irradiation group were irradiated with a 670 nm diode laser with an energy of 2.79 J/point, a power output 30 mW, a beam area of 0.028 cm², an energy density of 100 J/cm², an irradiance of 1.07 W/cm² for 93 s/point. Irradiation was performed in 12 points in the cranial skin flap portion. The total energy irradiated on the tissue was 33.48 J. The necrotic area was evaluated on postoperative day 7.RESULTS:The sham laser irradiation group presented a mean (± SD) necrotic area of 47.96±3.81%, whereas the active laser irradiation group presented 62.24±7.28%. There was a significant difference in skin-flap necrosis areas between groups (P=0.0002).CONCLUSION:LLLT (λ=670 nm) increased the necrotic area of random skin flaps in rats when irradiated with an energy of 2.79 J (100 J/cm²).     

Laser phototherapy effect on protein metabolism parameters of rat salivary glands

The aim of this study was to evaluate the effects of infrared diode laser phototherapy (LP) on tissues of the submandibular gland (SMG) and parotid gland (PG). Wistar rats were randomly divided into experimental (A and B) and control (C) groups. A diode laser, 808 nm wavelength, in continuous wave mode, was applied to the PG, SMG and sublingual gland in the experimental groups on two consecutive days. The doses were 4 J/cm² and 8 J/cm², and total energy was 7 J and 14 J, respectively. The power output (500 mW) and power density (277 mW/cm²) were the same for both experimental groups. In order to visualize the area irradiated by the infrared laser, we used a red pilot beam (650 nm) with 3 mW maximum power for the experimental groups. For the control group, the red pilot beam was the only device used. The SMG and PG were removed after 1 week of the first irradiation. Total protein concentration, amylase, peroxidase, catalase and lactate dehydrogenase assays were performed, as well as histological analysis. Statistical tests revealed significant increase in the total protein concentration for groups A and B in the parotid glands (P < 0.05). Based on the results of this study, LP altered the total protein concentration in rats’ parotid glands.     

Albumin-genipin solder for laser tissue repair

BACKGROUND: Laser tissue soldering (LTS) is an alternative technique to suturing for tissue repair that avoids foreign body reaction and provides immediate sealing of the wound. One of the major drawbacks of LTS, however, is the weak tensile strength of the solder welds when compared to sutures. In this study, a crosslinking agent of low cytotoxicity was investigated for its ability to enhance the bond strength of albumin solders with sheep intestine. STUDY DESIGN/MATERIALS AND METHODS: Solder strips were welded onto rectangular sections of sheep small intestine using a diode laser. The laser delivered in continuous mode a power of 170 +/- 10 mW at lambda = 808 nm, through a multimode optical fiber (core size = 200 microm) to achieve a dose of 10.8 +/- 0.5 J/mg. The solder thickness and surface area were kept constant throughout the experiment (thickness = 0.15 +/- 0.01 mm, area = 12 +/- 1.2 mm2). The solder was composed of 62% bovine serum albumin (BSA), 0.38% genipin, 0.25% indocyanin green dye (IG), and water. Tissue welding was also performed with a BSA solder without genipin, as a control group. The repaired tissue was tested for tensile strength by a calibrated tensiometer. Murine fibroblasts were also cultured in extracted media from heat-denatured genipin solder to assess cell growth inhibition in a 48 hours period. RESULTS: The tensile strength of the genipin solder was doubled that of the BSA solder (0.21 +/- 0.04 N and 0.11 +/- 0.04 N, respectively; P = 10(-15) unpaired t-test, N = 30). Media extracted from crosslinked genipin solder showed negligible toxicity to fibroblast cells under the culture conditions examined here. CONCLUSION: Addition of a chemical crosslinking agent, such as genipin, significantly increased the tensile strength of adhesive-tissue bonds. A proposed mechanism for this enhanced bond strength is the synergistic action of mechanical adhesion with chemical crosslinking by genipin.     

In vitro analysis of human tooth pulp chamber temperature after low-intensity laser therapy at different power outputs

In vitro studies have provided conflicting evidence of temperature changes in the tooth pulp chamber after low-level laser irradiation of the tooth surface. The present study was an in vitro evaluation of temperature increases in the human tooth pulp chamber after diode laser irradiation (GaAlAs, λ = 808 nm) using different power densities. Twelve human teeth (three incisors, three canines, three premolars and three molars) were sectioned in the cervical third of the root and enlarged for the introduction of a thermocouple into the pulp chamber. The teeth were irradiated with 417 mW, 207 mW and 78 mW power outputs for 30 s on the vestibular surface approximately 2 mm from the cervical line of the crown. The highest average increase in temperature (5.6°C) was observed in incisors irradiated with 417 mW. None of the teeth (incisors, canines, premolars or molars) irradiated with 207 mW showed temperature increases higher than 5.5°C that could potentially be harmful to pulp tissue. Teeth irradiated with 78 mW showed lower temperature increases. The study showed that diode laser irradiation with a wavelength of 808 nm at 417 mW power output increased the pulp chamber temperature of certain groups of teeth, especially incisors and premolars, to critical threshold values for the dental pulp (5.5°C). Thus, this study serves as a warning to clinicians that “more” is not necessarily “better”.     

Power density and exposure time of He-Ne laser irradiation are more important than total energy dose in photo-biomodulation of human fibroblasts in vitro.

The absorption spectrum of human fibroblast monolayers showed several absorption peaks, among them one at a wave-length of 630 nm. Cultures of these fibroblasts were subjected to He-Ne laser (632.8 nm) irradiation of various energy doses by varying power density and exposure time. On three consecutive days the cell monolayers were irradiated for periods between 0.5 and 10 min. Laser power varied from 0.55 to 5.98 mW. Both cell number and collagen type I production were determined for each irradiation condition within one experiment. Results show that laser power below 2.91 mW could enhance cell proliferation (as determined by cell counting), whereas higher laser power (5.98 mW) had no effect. Stimulatory effects were most pronounced at irradiation times between 0.5 and 2 min. Collagen type I production (as determined by an ELISA) was affected in the opposite direction to cell proliferation: when the cell proliferation was increased, collagen type I production was decreased. From these experiments it is clear that exposure time and power density determine the effects of laser irradiation. Both stimulation and inhibition of the observed cell properties can be obtained with the same laser on the same cells.     

GaAs (904-nm) laser radiation does not affect muscle regeneration in mouse skeletal muscle.

BACKGROUND AND OBJECTIVE: We evaluated the effect of GaAs (904-nm) laser, applied directly to the skin of injured muscle, in muscle regeneration. STUDY DESIGN/MATERIAL AND METHODS: Muscle injury was induced in the Tibialis anterior (TA) muscle by ACL myotoxin (5 mg/kg). Two groups were irradiated with doses of 3 (n = 8) and 10 J/cm(2)(n = 8). GaAs laser (power 1.5 mW, intensity 7.5 mW/cm(2), spot 0.2 cm(2)) was applied daily for five days. Contralateral TA received a sham procedure. RESULTS: Similar morphological aspects were found in both laser irradiated and sham muscles. No differences were found in the muscle weight, but animals irradiated with 10 J/cm(2) showed a significant gain of body weight (P = 0.002). CONCLUSIONS: Doses of 3 and 10 J/cm(2) of GaAs laser were not efficient to promote significant morphological changes in the regenerated skeletal muscle, but the dose of 10 J/cm(2) promoted significant gain of body weight.     

Course calendar

The beneficial effects of low energy laser irradiation on rheumatoid arthritis (RA) joints have been reported, but the mechanisms of action of low energy lasers in RA are unclear. The synovial membrane in cases of RA was studied histologically to observe the effects of low energy laser irradiation. Fourteen knee joints of RA cases, which had been scheduled for arthroplasty, were irradiated with a gallium-aluminium-arsenide (Ga-Al-As) laser (790 nm in wavelength and 10 mW of output power) prior to the surgical operation, at six points of the external aspect of the knee joint for 80 seconds at each points once a day for 6 days. On the day following the last irradiation, pieces of synovial membrane from the lateral irradiated area and from the median nonirradiated area as a control were resected during the arthroplasty. The histological findings of the irradiated synovial membrane showed flattening of epithelial cells, decreased villous proliferation, narrowed vascular lumen, and less infiltration of inflammatory cells compared with those of nonirradiated synovia. The evaluation of slides was done in a blinded manner, and significant differences was seen by Wilcoxon's t-test (P < 0.01). Histological findings suggested that the low energy laser irradiation induced suppression of inflammation in the synovial membrane of RA. © 1994 Wiley-Liss, Inc.     

Low-level laser therapy and light-emitting diode effects in the secretion of neuropeptides SP and CGRP in rat skin

The phototherapy effects in the skin are related to biomodulation, usually to accelerate wound healing. However, there is no direct proof of the interrelation between the effects of low-level laser therapy (LLLT) and light-emitting diode (LED) in neuropeptide secretion, these substances being prematurely involved in the neurogenic inflammation phase of wound healing. This study therefore focused on investigating LLLT and LED in Calcitonin gene-related peptide (CGRP) and substance P (SP) secretion in healthy rat skin. Forty rats were randomly distributed into five groups with eight rats each: Control Group, Blue LED Group (470 nm, 350 mW power), Red LED Group (660 nm, 350 mW power), Red Laser Group (660 nm, 100 mW power), and Infrared Laser Group (808 nm, 100 mW power) (DMC® Equipamentos Ltda., São Carlos, São Paulo, Brazil). The skin of the animals in the experimental groups was irradiated using the punctual contact technique, with a total energy of 40 J, single dose, standardized at one point in the dorsal region. After 14 min of irradiation, the skin samples were collected for CGRP and SP quantification using western blot analysis. SP was released in Infrared Laser Group (p?=?0.01); there was no difference in the CGRP secretion among groups. Infrared (808 nm) LLLT enhances neuropeptide SP secretion in healthy rat skin.     

Effect of the ArF excimer laser on human enamel.

Human enamel surface was irradiated with ArF excimer laser and examined under light microscopy and scanning electron microscopy (SEM). Enamel surface was irradiated at three different areas with different energy fluences. It is demonstrated that the ArF excimer laser causes ablation of the calcified hard enamel tissue. Ablation curves were measured. There was no significant difference found in the etch depth between the three different areas of enamel surface. The morphology of the irradiated areas seen under the SEM was found to be dependent on energy fluence. It changed with increase in energy fluence from being etched to forming a smooth, fused, glaze-like surface and then at very high energy fluences producing a rough surface. The influence of the laser irradiation was confined to the irradiated area only, with no visible heat damage to the surroundings. These results suggest that excimer laser could be applied in a controlled and defined manner for tooth enamel treatments in dentistry.     

Efficiency of low-level laser therapy in reducing pain induced by orthodontic forces

Abstract Objective: The aim of this study was to investigate the effect of low-level laser therapy (LLLT) on reducing post-adjustment orthodontic pain via evaluation of gingival crevicular fluid (GCF) composition changes at the level of prostaglandin-E(2) (PGE(2)) and visual analogue scale (VAS). Background data: LLLT has been found to be effective in pain relief. PGE(2) has the greatest impact on the process of pain signals and can be detected in GCF in order to investigate the response of dental and periodontal tissues in a biochemical manner. Materials and methods: Nineteen patients (11 females and 8 males; mean age 13.9 years) were included in this study. Maxillary first molars were banded and then a randomly selected first molar at one side was irradiated (λ820?nm; continuous wave; output power: 50?mW; focal spot: 0.0314?cm(2); exposure duration: 5?sec; power density: 1.59?W/cm(2); energy dose: 0.25?J; energy density: 7.96?J/cm(2) for each shot), while the molar at the other side was served as placebo control. The GCF was collected from the gingival crevice of each molar to evaluate PGE(2) levels, before band placement, 1 and 24?h after laser irradiation. Pain intensity was analyzed at 5?min, 1?h, and 24?h after band placement by using VAS. Results: Although no difference was found in pain perception at 5?min and 1?h, significant reduction was observed with laser treatment 24?h after application (p<0.05). The mean PGE(2) levels were significantly elevated in control group, whereas a gradual decrease occurred in laser group. The difference in PGE(2) levels at both 1 and 24?h were statistically significant between two groups (p<0.05). Conclusions: The significant reductions in both pain intensity and PGE(2) levels revealed that LLLT was efficient in reducing orthodontic post-adjustment pain.     

Concentrated autologous plasma protein: a biochemically neutral solder for tissue welding.

BACKGROUND AND OBJECTIVE: Xenographic or allographic serum protein solders used for laser welding may have immunologic and/or pathogenic complications. The objective of these studies was to develop a safe, autologous solder. STUDY DESIGN/MATERIALS AND METHODS: Five methods of preparing concentrated autologous plasma protein solder (CAPPS) were evaluated. Next, the CAPPS was evaluated via (1) thermal denaturation studies using differential scanning calorimetry, (2) tissue welding studies to characterize both acute and healing properties. RESULTS: The optimal concentration method to produce CAPPS rapidly was a dialysis method using chemical (osmotic) forces. The CAPPS showed similar denaturation profiles to serum albumin (SA) solders. Acutely, CAPPS provided comparable breaking strengths to SA solders. At 7 days, there was no significant difference in breaking strength or histology between 50% human SA solder and CAPPS (using a porcine skin model). CONCLUSIONS: These studies demonstrate that the CAPPS system provides acceptable acute and chronic properties for laser welding.     

Biodegradable polymer film reinforcement of an indocyanine green-doped liquid albumin solder for laser-assisted incision closure

BACKGROUND AND OBJECTIVE: The purpose of this study was to determine whether solid material reinforcement of a liquid albumin solder coagulum could improve the cohesive strength of the solder and, thus, the ultimate breaking strength of the incision repair in vitro. STUDY DESIGN/MATERIALS AND METHODS: A 50%(w/v) bovine serum albumin solder with 0.5 or 2.5 mg/ml indocyanine green (ICG) dye was used to repair an incision in bovine aorta. The solder was coagulated with an 806-nm continuous wave diode laser. A 50-micrometer-thick poly(DL-lactic-co-glycolic acid) film was used to reinforce the solder (the controls had solder but no reinforcement). Acute breaking strengths were measured, and the data were analyzed by Student's t-test. RESULTS: Observations of the failure modes indicate cohesive strength reinforcement of the test specimens vs. the controls. The 2.5 mg/ml ICG reinforced solder was stronger than the controls without reinforcement (P < 0.05) for all laser powers tested. There was no difference between the test specimens and the controls with 0.5 mg/ml ICG solder for low laser powers, but at higher laser powers, the reinforced solder was stronger than the controls (P < 0.05). CONCLUSION: Reinforcement of liquid albumin solders in laser-assisted incision repair seems to have advantages in terms of acute breaking strength over conventional methods that do not reinforce the cohesive strength of the solder.     

Preliminary study of laser welding for aortic dissection in a porcine model using a diode laser with indocyanine green

BACKGROUND AND OBJECTIVES: The objective of this study was to determine whether a dissected aorta could be welded by a diode laser with a solder using an in vitro porcine aortic dissection model. STUDY DESIGN/MATERIALS AND METHODS: Porcine aortic strips were dissected into two flaps and the dissected faces were immersed in a solution of indocyanine green. The two flaps were pressed at 0.2 kg/cm2 with contact between the two immersed faces. The pressed flaps were irradiated with a diode laser (810 nm) at intensities of 170-425 W/cm2 for 8 seconds. The welded flaps were studied by light microscopy and the adhesive strengths were measured. RESULTS: The irradiated flaps were successfully welded. The breaking stress, the maximum stress recorded in a stress-strain curve, increased with increase in irradiation intensity up to 396 W/cm2 (2.7 x 10(2) mmHg) and decreased when the intensity reached 425 W/cm2. In the specimen irradiated at 396 W/cm2, the welded faces showed continuous fusion of elastin layers, while some voids were seen between the welded faces in the specimen irradiated at 425 W/cm2. CONCLUSIONS: The dissected porcine aortas were successfully welded using a laser with solder. The results suggest that the welded aorta can bear physiological blood pressure.     

Computer analysis of laser dosimetry data: a method of accurate energy density delivery

In the past, utilization of the laser in medicine has been limited by the lack of accurate quantification of the energies delivered to the tissue. Data obtained in the course of this investigation have demonstrated the relationships which exist between the energy delivered to the tissue and the optical system composed of the fiber and focusing lens. A continuous-wave multimode Nd:YAG laser (1,064 nm) was used in these experiments. Utilizing the beam scan technique previously described, we recorded over 100 beam profiles at various distances from the handpiece (fiber optic and lens). Computer analysis of our data established the mathematical correlation between the surface area of the irradiated spot and the distance of the handpiece to the target, thus allowing us to predict the surface area of the irradiated spot to any desired distance. By duplicating our methods with his particular optical system, the clinician or any laser user has the capacity to determine the energy delivered to the tissue (J/cm2) by knowing the power of the laser (watts), the time of exposure (seconds), and the distance of the handpiece to the treatment site (centimeters).     

Low power laser irradiation alters the rate of regeneration of the rat facial nerve

Low power laser irradiation has been reported to cause biological effects due to the photochemical and/or photophysical action of the radiation. This study determined quantitatively if transcu-taneous low power laser irradiation can affect the regeneration of the rat facial nerve. The facial nerve was crushed unilaterally in anesthetized rats and transcutaneously irradiated daily with a laser beam directed at the area of the crush injury. Laser treatment began on the day of the crush injury and was continued daily for 7, 8, or 9 days. Preliminary experiments determined the most effective wavelength, laser power, length of irradiation, and treatment schedule. The wavelengths examined were 361, 457, 514, 633, 720, and 1064. The laser powers and lengths of irradiation examined ranged from 8.5 to 40 mW and 13 to 120 min. Irradiation treatment was done daily, on alternating days and on the first 4 days postcrush. The most effective laser parameters for the low power treatment included daily irradiation with a helium-neon (HeNe) or argon pumped tunable dye laser a wavelength of 633 nm, with a power of 8.5 mW for 90 minutes (45.9 J, 162.4 J/cm²). The number of horseradish peroxidase (HRP) labeled neurons in the facial motor nucleus was used as an assay of the degree of regeneration. In rats in which the facial nerve was crushed but not irradiated, the average number of HRP labeled neurons in the facial nucleus was 22 on day 7 postcrush, 54 on day 8, 116 on day 9, and 1,149 on day 10. After HeNe or argon pumped tunable dye laser irradiation, the average number of HRP-labeled neurons increased to 34 on day 7 postcrush, 148 on day 8, and 1,725 on day 9. There was a statistically significant difference between the control and irradiated rats on day 9 post-crush (P < 0.01). These data indicate that transcutaneous low power irradiation with the lasers and parameters involved in this study increased the rate of regeneration of rat facial nerve following crush injury. © 1993 Wiley-Liss, Inc.     

Low-level laser irradiation,cyclooxygenase-2 (COX-2) expression and necrosis of random skin flaps in rats

Skin flaps are still a matter of concern among surgeons, as failures can occur leading to flap necrosis. However, low-level laser irradiation has been reported as an effective tool to improve the viability of ischemic flaps, yet its mechanisms of action remain unclear. We investigated the effect of low-level laser irradiation on the viability of random skin flaps in rats and determined COX-2 expression in the flap pedicle. The study animals comprised 24 EPM-1 Wistar rats which were randomly allocated into three equal groups. A cranially based dorsal random skin flap measuring 10 × 4 cm was created in all the animals. In one group, laser irradiation was simulated (sham group), and in the other two groups the animals were irradiated at 12 points with 0.29 J at 20 mW (energy density 10.36 J/cm², irradiance 0.71 W/cm²), or with 7.3 J at 100 mW (energy density 260.7 J/cm², irradiance 3.57 W/cm²). These procedures were applied to the cranial half of the flap immediately after surgery and were repeated on days 2 and 5 after surgery. The percentage necrotic area was determined on day 7 after surgery by the paper template method. The immunohistochemical expression of COX-2 in the samples was given scores from 0 to 3. The necrotic area was smaller in group irradiated at 7.3 J compared to sham-treated group and to the group irradiated at 0.29 J (P < 0.05); there was no difference between the sham-treated group and group irradiated at 0.29 J. COX-2 expression was lower in the group irradiated at 7.3 J than in the sham-treated group and the group irradiated at 0.29 J (P < 0.001). Low-level laser therapy was effective in decreasing random skin flap necrosis in rats using a laser energy of 7.30 J per point. Laser irradiation also decreased the expression of COX-2 in the flap pedicle.     

CO2 Laser nerve welding: Optimal laser parameters and the use of solders in vitro

To improve the welding strength, an in vitro study was performed to investigate the bonding strength of CO₂ laser nerve welding (LNW), with and without the use of human albumin solution, dried albumin solution, egg white, fibrinogen solution, fibrin glue, and red blood cells as a solder. Fifteen different combinations of laser power (50, 100, and 150 mW) and pulse duration (0.1 to 3 s) were used with a spot size of 320 μm. The results have been compared to suture, fibrin glue, and laser-assisted nerve repair (LANR). The strongest welds (associated with whitening and caramelization of tissue) were produced at 100 mW with pulses of 1.0 s and at 50 mW with pulses of 3 s. The use of a dried albumin solution as a solder at 100 mW with pulses of 1 s increased the bonding strength 9-fold as compared to LNW (bonding strength 21.0 ± 8.6 g and 2.4 ± 0.9 g, respectively). However, positioning the nerves between cottons soaked in saline for 20 minutes resulted in a decrease of the bonding strength (9.8 ± 4.5 g). The use of a 20% albumin solution and egg white, both at 50 mW with pulses of 3 s, resulted in a bonding strength of, respectively, 5.7 ± 2.1 g and 7.7 ± 2.4 g. Other solders did not increase the bonding strength in comparison to LNW. The substantial increase in bonding strength for some solders suggests that it is worthwhile to investigate the dehiscence rate and nerve regeneration of solder enhanced LNW in an in vivo study. © 1994 Wiley-Liss, Inc.     

Effect of low-power laser irradiation on protein synthesis and ultrastructure of human gingival fibroblasts

BACKGROUND AND OBJECTIVES: Low-power lasers improve wound healing. Cell proliferation and protein secretion are important steps of this process. The aim of this study was to analyze both protein synthesis and ultrastructural morphology of human gingival fibroblasts irradiated by a low-power laser. STUDY DESIGN/MATERIALS AND METHODS: The cell line FMM1 was grown in nutritional deficit. Laser irradiation was carried out with a gallium-aluminum-arsenate (Ga-Al-As) diode laser (904 nm, 120 mW, energy density of 3 J/cm(2)). The protein synthesis analysis and ultrastructural morphology of control (non-irradiated) and irradiated cultures were obtained. RESULTS: There were changes in the structure of cytoplasm organelles of treated cells. The procollagen was not altered by the laser irradiation; however, there were a significant reduction of the amount of protein in the DMEM conditioned by irradiated cells. CONCLUSIONS: Low-power laser irradiation causes ultrastructural changes in cultured fibroblasts. We suggest that these alterations may lead to disturbances in the collagen metabolism.     

Effects of Er,Cr:YSGG laser irradiation on the surface characteristics of titanium discs: An in vitro study

Lasers are used to modify the surfaces of dental implants or to decontaminate exposed implant surfaces. However, research is lacking on whether the laser causes any change on the surfaces of titanium implants. We aimed to determine the effects of laser treatment on the surface characteristics of titanium discs. Nine discs were fabricated using grade-V titanium with resorbable blast texturing surface characteristics. The discs were irradiated with an erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser under different experimental conditions (R1–9). Scanning electron microscopy was used to evaluate implant surface topography qualitatively, and a mechanical contact profilometer was used to evaluate surface roughness. The R3 and R5 parameters caused no measurable change. Minor cracks and grooves were observed in discs treated with the R1, R2, R4, R7 and R9 parameters. Major changes, such as melting, flattening and deep crack formation, were observed in discs subjected to R6 (2 W, 30 Hz, 2 mm. distance, 30 s) and R8 (3 W, 25 Hz, 2 mm. distance, 45 s) parameters. The lowest surface roughness value was obtained with the R8 parameter. Irradiation distance, duration, frequency and power were the most significant factors affecting surface roughness. Parameters such as wavelength, output power, energy, dose and duration should be considered during irradiation. The results of this study indicate that the distance between the laser tip and the irradiated surface should also be considered.