Journal of lasers in medical sciences最新文献

Introduction: This study assessed the effect of low-level laser therapy (LLLT) on the osseointegration of immediately loaded implants with a connective tissue graft (CTG). Methods: This clinical trial was conducted on patients with buccal bone dehiscence requiring dental implants. A CTG was harvested from the palate and placed in the labial side by considering the 2 mm distance between the implant thread and bone. Autogenous bone was harvested from the tuberosity, mixed with the allograft, and implanted at the site. After sufficient torquing of the implant, a customized abutment was fabricated and placed. The patients were randomly assigned to two groups (n=5) of intervention and control. The patients in the intervention group received LLLT with a 940 nm gallium-aluminum-arsenide laser while those in the control group received placebo irradiation. The primary implant stability was measured before the delivery of customized abutment while the secondary implant stability was measured after 12 weeks by Osstell® and reported as the implant stability quotient (ISQ). Results: No significant difference was found in secondary ISQ between the laser and control groups (P>0.05). In the intervention group, a significant difference was found between the primary and secondary ISQ in the buccolingual dimension (P<0.05) but not in the mesiodistal dimension (P>0.05). The two groups had no significant difference in gingival thickness or vertical bone gain (P>0.05). All implants were successful with no complications. Conclusion: LLLT had a significant positive efficacy for the enhancement of secondary stability of implants in the buccolingual dimension. CTG showed optimal efficacy for the treatment of buccal bone dehiscence.

Introduction: Diabetes is associated with several debilitating complications, including the development of diabetic foot ulcers (DFUs), which can have serious consequences. This study emphasizes a multidisciplinary approach, providing a thorough overview of DFU pathogenesis and available treatments. Methods: An extensive literature review, covering studies published between 2000 and 2023, was conducted to gather data on DFU pathophysiology and treatments, including wound dressings, photobiomodulation, off-loading devices, adjunct medicines, and stem cell therapy. Results: DFUs are complicated due to infection, ischemia, and neuropathy. Sufficient wound dressings maintain a moist environment, promoting autolytic debridement and facilitating the healing process. Through cellular mechanisms, photobiomodulation therapy (PBM) was observed to expedite the healing process. Additionally, off-loading devices were invented to reduce ulcer pressure and promote healing. Adjunct therapies such as negative pressure wound therapy and hyperbaric oxygen therapy were identified as valuable tools for enhancing healing outcomes. Furthermore, autologous and allogeneic stem cell treatments exhibited the potential for promoting tissue regeneration and expediting the healing process. Conclusion: The complex pathophysiology of DFUs necessitates a multimodal treatment approach. Essential components include PBM, wound dressings, off-loading devices, adjunct treatments, and stem cell therapy.

Introduction: The adhesion ability of mesenchymal stem cells can significantly affect their viability and is considered a prerequisite for cell therapy. The current study sought to evaluate the effect of fibroblast growth factor 2 (FGF2) and low-level laser therapy (LLLT), either individually or in conjunction, on the adhesion and proliferation of periodontal ligament stem cells (PDLSCs) when applied on the first day of cell seeding. Methods: The experimental groups of this study comprised a control group and different combinations of adjunctive FGF2 (50 ng/mL) and LLLT with an 808 nm diode laser in one (LLLT-1) or two sessions (LLLT-2) of irradiation. The proliferation and adhesion of cells were evaluated by using the methylthiazolyl tetrazolium (MTT) assay and 4',6-diamidino-2-phenylindole (DAPI) staining. All experiments were done in triplicates on the first, third, and fifth days after cell seeding. Two-way ANOVA and post hoc Tukey tests were used to analyze the data of the MTT assay. P<0.05 was considered statistically significant. Results: One-day post-culture, only significant differences were found between the control group and the FGF2 (P=0.04) and FGF2+LLLT-2 application (P=0.04) groups. After three days post-cell culture, only a significantly higher proliferation rate was found in the control group than in the FGF2 group (P=0.01). After five days, the control group and LLLT-2 groups showed significantly higher amounts of proliferation compared to the other groups (P<0.05). DAPI staining qualitatively confirmed the results of the MTT assay. Conclusion: The LLLT can be applied to PDLSCs on the day of seeding without causing a notable decrease in their viability and adhesion. Conversely, the administration of FGF2 should be restricted on the seeding day and postponed to subsequent days as it may have adverse effects on their adhesion and proliferation.

Introduction: Fiber-reinforced composite posts (FRCP) have become popular due to their multiple advantages in teeth with extensive crown destruction. Proper disinfection is essential for the successful bonding of these posts. Commonly used solutions for cleaning and disinfecting the root canals adversely affect the bond strength (BS). Photodynamic therapy is an alternative method for irrigating the root canal and disinfecting the post space.This study was designed to evaluate the impact of photodynamic therapy on the BS of fiber posts to root canal dentin. Methods: Human maxillary canines were recruited for this study. The tooth crowns were removed at the cervical line and endodontically treated. After fiber post spaces were prepared, the teeth were assigned to five groups based on the light-sensitive material: deionized water, indocyanine green and 810-nm laser, methylene blue and 660-nm laser, toluidine blue and 635-nm laser, curcumin and LED. The posts were cemented after photodynamic therapy. Cervical, middle, and apical samples were prepared by transverse sectioning. Push-out bond strength (PBS) values were measured in a universal testing machine. Finally, the data underwent statistical analyses with ANOVA and Howell-Games tests. Results: One-way ANOVA revealed no significant differences between the groups (P<0.001). The Games-Howell test showed that curcumin (7.23±3.75) and the control group (5.92±4.04) had a similar BS (P>0.005). The BS was lower in the methylene blue (3.34±2.15), indocyanine green (2.59±3.16), and toluidine blue (2.45±1.73) groups than in the control group (P<0.005). Conclusion: Unlike other light-sensitive materials, curcumin did not adversely affect the BS.

Introduction: Numerous strategies have been investigated for addressing recurrent implantation failure (RIF) and enhancing endometrial receptivity, yet agreement on the optimal intervention remains elusive. Our investigation endeavors to assess the effect of low-level laser therapy (LLLT) on pregnancy outcomes in individuals who have undergone a minimum of three unsuccessful embryo transfer cycles (ET). Methods: In our randomized single-blinded clinical trial, we enrolled thirty females with a medical history of RIF who were eligible for frozen-thawed embryo transfer (FET). Through a random allocation sequence, the participants were divided into two groups. The LLLT was performed one cycle before blastocyst transfer in 15 cases using a New Age BIOLASER device (New Age Co., Italy) with a 900-milliwatt power output and an 850-nm wavelength. The irradiation sessions were conducted transabdominal on the hypogastric area. The considered outcomes were biochemical pregnancy, identified by a positive blood pregnancy test, and clinical pregnancy, confirmed through visualization of the gestational sac using ultrasonography. Results: The mean age of the subjects was 34.17 years, and they had undergone three to seven previous embryo transfers. There was no significant difference in basic characteristics between the group undergoing laser treatment and the control group. However, the laser-treated group exhibited elevated rates of both biochemical and clinical pregnancies compared to the control group (46.7% vs. 33.3%; P==0.710 and 33.3% vs. 20.0%; P=0.682 respectively). Conclusion: To our knowledge, this study represents the first single-blinded randomized clinical trial to assess the effectiveness of LLLT pretreatment in individuals with RIF. The findings propose that LLLT may potentially enhance biochemical and clinical pregnancy rates among RIF patients.

Introduction: Photothermal therapy (PTT) by using a near-infrared (NIR) laser, as a successful treatment of cancer, has attracted extensive attention of researchers. Its advantages as a noninvasive and suitable method have been confirmed. Discovery of the NIR laser molecular mechanism at the cellular level via system biology assessment to identify the crucial targeted genes is the aim of this study. Methods: RNA-seq series of six samples were retrieved from Gene Expression Omnibus (GEO) and pre-evaluated by the GEO2R program for more analysis. The significant differentially expressed genes (DEGs) were determined and studied via gene expression analysis, protein-protein interaction (PPI) network assessment, action map evaluation, and gene ontology enrichment. Results: HSPA5, DDIT3, TRIB3, PTGS2, HMOX1, ASNS, GDF15, SLC7A11, and SQSTM1 were identified as central genes. Comparing the central genes and the determined crucial genes via gene expression analysis, actin map results, and gene ontology enrichment led to the introduction of HSPA5, DDIT3, PTGS2, HMOX1, and GDF15 as critical genes in response to the NIR laser. Conclusion: The results indicated that the principle biological process "Endoplasmic reticulum unfolded protein response" and HSPA5, DDIT3, PTGS2, HMOX1, and GDF15 are the crucial targets of the NIR laser. The results also showed that the NIR laser induces stress conditions in the irradiated cells.

Introduction: This study was carried out to assess and compare the efficacies of transcutaneous electrical nerve stimulation (TENS) and low-level laser therapy (LLLT) applied to sciatic Valleix points to reduce sciatica in patients with chronic lumbar radiculopathy. Methods: The study population consisted of 164 patients with chronic radicular pain caused by LDH. The remaining 75 patients were studied in three groups. TENS and hotpack were applied to the lower back region of all patients. In addition, group 1 (n=24), group 2 (n=25), and group 3 (n=26) received LLLT (4 J/cm² for each point), TENS, and sham LLLT, respectively, on sciatic Valleix points five days a week, for three weeks (15 sessions). Outcomes were assessed at the beginning of the treatment, after completion of 3 weeks of treatment, and after three months (follow-up). Results: Post-treatment assessments indicated that all parameters investigated within the scope of the study improved in all three groups, except for the VAS leg pain (VASLP) score in group 3. Post-treatment VASLP and DN4 scores of group 1 were significantly superior to those of group 2 (P˂0.001). Follow-up assessments revealed an improvement only in the VASLP score and in group 1. The VASLP, DN-4, and ODI scores of groups 1 and 2 were significantly superior to those of group 3. There was no significant difference between the groups in the PSQI score and lumbar ROM value. Conclusion: Both LLLT and TENS were found to be effective in treating the sciatic nerve associated with lumbar disk herniation with radiculopathy. LLLT was found to be more effective than TENS in reducing leg and neuropathic pains. Follow-up assessments revealed that the only lasting effect of the treatments, which continued into the third month, was the improvement in leg pain.

Introduction: Diabetes is a highly prevalent disease worldwide. Despite routine treatments, there is no effective treatment approach for patients with diabetic foot ulcers (DFUs). A new approach to reduce complications and control DFU is low-level laser therapy (LLLT). In the present study, we evaluated the therapeutic effects of LLLT on the symptoms of DFU patients. Methods: Sixty diabetic patients with DFU were included in this randomized clinical trial and were randomly allocated into two groups of laser (n=30) and control (n=30) with signed written consent. The LLLT group underwent visible and infra-red laser therapy and conventional medical treatment, while the control group received only conventional medical treatment. The total laser irradiation sessions of the patients were 20 sessions, (three sessions a week) and each session lasted for 30 minutes over the entire surface of the wound. The power density per session for each laser was calculated to be 35.65 mW/cm² with an energy density of 64.17 J/cm². Results: The mean area of ulcers in the LLLT group reduced significantly (P<0.001) from 441.7±365.5 mm² before LLLT to 163.9±213.9 mm² from the baseline up to the last session of LLLT, indicating a 62.99% reduction in mean ulcer area. In the control group, the mean ulcer area did not change significantly. Wagner's classification of the patients in the LLLT group reduced to lower grades significantly (P<0.01), while the classification moved towards higher grades in the control group (P<0.08). Conclusion: In this study, we showed the effectiveness of LLLT in the reduction of the surface and depth of DFUs. The results documented that patients experienced significant improvements in the healing of their foot ulcers after laser therapy. It is recommended that the LLLT be considered as a non-invasive method for the treatment of DFU patients.

Introduction: Studies on head and neck cancer (HNC) patients undergoing radiotherapy have revealed increased numbers of Candida spp., leading to oral candidiasis and oral mucositis. The effects of laser therapy on Candida spp. have been studied with varied results. This study aimed to investigate the effect of low-level laser therapy (LLLT) on C. albicans colonies isolated from HNC patients undergoing radiotherapy. Methods: This study included a treated group, wherein 11 C. albicans isolates were obtained from the saliva of HNC patients undergoing radiotherapy at a dose exceeding 30 Gy. The control groups consisted of an untreated negative control and a positive control treated with nystatin. The treatment groups were subjected to LLLT in continuous mode for 50 seconds at a wavelength of 976 nm, 0.1 W at a dose of 5 J/cm² for Laser 1 (L1) group and 0.2 W at a dose of 10 J/cm² for Laser 2 (L2) group. The tests were conducted using C. albicans inoculum equivalent to a 0.5-McFarland suspension on 96-well plates. All test group inoculums were then cultured on Sabouraud dextrose agar (SDA), and the colony count was assessed at 10⁴ CFU/mL. Results: LLLT at 5 and 10 J/ cm² reduced C. albicans colonies by 7.01% and 10.94%, respectively, but the reductions were not statistically significant (P>0.05). Nystatin eliminated all the colonies. Conclusion: LLLT shows potential for reducing C. albicans colonies in HNC patients undergoing radiotherapy. However, further studies with varied parameters and methods are necessary.

Introduction: Polycystic ovary syndrome (PCOS) is a complex condition that can have various symptoms and complications, one of which is infertility. Dysregulation of miRNA has been associated with the pathogenesis of numerous illnesses such as PCOS. In this study, we evaluated the effect of photobiomodulation therapy (PBMT) and exosome therapy (EXO) on the regulation of miRNA and nucleus acetylation in a PCOS oocyte. Methods: In this research, 36 oocytes divided into three groups: control, EXO, and PBM (Wavelength of 640 nm). Subsequently, in-vitro maturation (IVM) was evaluated. Real-time PCR was used to evaluate miRNA-21,16,19,24,30,106,155 and GAPDH. Afterward, oocyte glutathione (GSH) and nucleus acetylation were measured by H4K12. Results: The expression of the miR-16, miRNA-19, miRNA-24, miRNA-106 and miRNA-155 genes in the EXO and PBMT groups was significantly down-regulated in comparison to the control group, but the expression of miRNA-21 and miR-30 significantly increased in the EXO and PBMT groups in comparison to the control group. The EXO and PBMT significantly increased GSH and nucleus acetylation (P<0.0001). Conclusion: The results of this study showed that the use of EXO and PBMT can improve GSH and nucleus acetylation in the PCOS oocyte and also change the expression of miRNAs.