Photobiomodulation, photomedicine, and laser surgery最新文献

Objective: This study provided clinical findings supporting the use of combination techniques/products and Nd:YAP 1340 nm fractional laser therapy, for soft-tissue augmentation in light- and darker-skin phototypes. Background: The face's aging process is complex and involves skin alterations, connective tissues, bone, and fat layers of the face. Methods: A total of 17 female patients were treated for wrinkles and for scars with the use of Nd:YAP 1340 nm fractional laser combined with other cosmetic therapies. The mean of 4.6(±1.9) laser treatment sessions every 1 month were performed. The combined therapy was administered every 3 months during the total course of the laser treatments. Results: The total mean improvement was 3.64(±0.49). Clinical images showed a visible aesthetic improvement. No adverse events have been reported. Conclusion: The combination therapies used have shown promise in maintaining safety and tolerability while improving patient results for the management of skin aging.

Objective: Diabetes mellitus is increasing worldwide. Photobiomodulation (PBM) is proposed as a therapeutic method in various medical concerns. This study aimed to compare the effects of PBM at the wavelengths of 660, 808, or 660 + 808 nm on alveolar bone healing in diabetic rats. Methods: Bilateral maxillary first molars were extracted from diabetic Wistar rats (n = 36). Right-sided sockets were treated by an In-Ga-Al-P laser at 660 nm (7.2 J/cm², 24 s; DM660), Ga-Al-As laser at 808 nm (7 J/cm², 14 s; DM808), or a combination of these two sets (DM-dual) (n = 12). Left sides served as controls. On days 7 or 14, specimens were assigned for histomorphometric or real-time PCR analysis of runt-related transcription factor 2, osteocalcin, collagen I, and vascular endothelial growth factor expression. Results: Irradiated sockets of groups DM-808 and DM-dual showed a significant increase in bone tissue and blood vessel establishment as compared to DM-660. Further, group DM-dual exhibited the least amount of fibrotic tissue as compared to the other groups. Conclusions: Within our study limits, the present experiment suggested PBM at 808 nm, alone or combined with 660 nm irradiation, could promote alveolar bone healing, along with minimal fibrosis induction, in diabetic rats.

Objective: Rheumatoid arthritis causes inflammation, pain, and joint degradation, necessitating treatment with anti-inflammatory drugs and corticosteroids, posing various challenges. We aimed to evaluate the effects of photobiomodulation (PBM) at two different doses associated to platelet-rich plasma (PRP) in an in vivo model of induced acute arthritis in Wistar rats' knee. Methods: Eighty-four Wistar rats were assigned into seven groups, including animals treated with PBM and/or PRP. On day 0, arthritis was induced in sham and treated groups through the intra-articular injection of zymosan (200 μg). Twenty-four hours after induction, the PBM groups were treated with an AsGaAl laser, whereas the PRP-treated groups received intra-articular injections with a concentration of 8 × 10⁵ platelets obtained from another four animals. After 3 days, the animals were euthanized, and the interleukin (IL)-6 and complement C3 gene and protein expression levels were analyzed. Statistical analysis was performed using the mean ± SD with analysis of variance and Tukey's posttest, with a significance level set at 5% (p < 0.05). Results: Synovial inflammation decreased in PBM-treated groups; however, PRP alone showed no significant difference. Gene expression analysis revealed a significant difference in IL-6 and C3 levels in the PBM and PBM+PRP-treated groups. Meanwhile, the PRP alone group exhibited significance for IL-6. Moreover, the PBM and PBM+PRP-treated groups showed a significant difference in C3 protein expression levels, whereas the PRP alone group showed no difference. Conclusion: The increase in cellular activity in the synovial membrane and the decrease protein expression levels are owing to the reduction in proinflammatory mediators following PBM therapy.

Objective: The purpose of this study was to demonstrate heat transfer within oral soft tissues using different lasers under the effect of local anesthetics (LA). Methods: Bovine tongue slices were placed in between two glass slides and at a distance from a thermographic camera. In total, 2-cm-long 240 incisions were made along the surface of the tissue parallel to glass slides and the camera capture field. Incisions were performed using 445-nm and infrared (IR) lasers (970 nm and 980 nm on a continuous wave at 2 W) with 320 µm-initiated (concentrated energy at the tip provided by a blue articulated paper and laser irradiation) and noninitiated (defused energy) fiber (30-sec irradiation period). LA was injected into the specimens before irradiation. The temperature changes in °C (ΔT) and vertical and lateral heat transfer (in mm) were recorded at 10-sec intervals for 30 sec, using thermographic images. The amount of lateral and vertical heat transfer was measured. A repeated analysis of variance statistical comparison test was used to analyze differences between the lateral (width) and the vertical (height) heat transfer for initiated and noninitiated lasers and different lasers. Results: The maximum ΔT in °C utilizing initiated tips of 970, 980, or 445 nm were 11.82 ± 3.46, 7.66 ± 3.24, and 18.94 ± 7.01 and using noninitiated tips were 8.27 ± 1.69, 8.87 ± 2.40, and 12.31 ± 8.65, respectively. Heat transfers (height/width) for initiated were 40.65 ± 10.40/90.65 ± 10.77 mm, 41.50 ± 11.83/83.95 ± 11.20 mm, and 33.70 ± 9.10/95.10 ± 11.17 mm and for noninitiated lasers were 52.95 ± 6.89/96.10 ± 11.17 mm, 47.75 ± 7.41/93.75 ± 14.96 mm, and 31.35 ± 11.40/75.20 ± 19.68 mm, respectively. A statistically significant difference was found between all lasers (p < 0.05) for initiated and noninitiated lasers (except for 970/980 nm for noninitiated lasers). Lower penetration depth (p < 0.05) at 445-nm diode and greater lateral heat spreading (p < 0.05) were identified under LA especially utilizing noninitiated tips without significant difference in IR lasers. Conclusions: LA might negatively influence soft tissues creating scattering when noninitiated tips are used and IR diode laser technology.

Aim: The study aims to assess the efficacy of rose bengal (RB)-mediated antimicrobial photodynamic therapy (a-PDT) as an adjunct to scaling and root planing in the management of chronic periodontitis patients in terms of clinical parameters like gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL), and microbiological parameters like total microbial count, total red complex organism count, Porphyromonas gingivalis count, Treponema denticola count, and Tannerella forsythia count. Materials and Methods: In this randomized controlled clinical trial, a total of 30 patients were recruited who met the inclusion criteria. The participants were randomly allocated into group A with scaling and root planning (SRP) alone and group B with SRP + a-PDT. The clinical and microbiological parameters were measured at baseline and at 3-month follow-up. Intergroup and intragroup comparisons were performed using independent t test and paired t test, respectively. Value of p < 0.05 was considered as statistically significant. Results: At 3-month follow-up, group B treated with SRP + a-PDT showed statistically significant reduction in GI (0.58 ± 0.20) and PPD (1.81 ± 0.32 mm), gain in CAL (0.73 ± 0.04 mm), and reduction in total microbial count [2.80 ± 0.08 × 10⁴ colony forming unit (CFU)], total red complex count (0.29 ± 0.14 × 10² CFU), P. gingivalis count (0.43 ± 0.13 × 10² CFU), T. denticola count (0.61 ± 0.04 × 10² CFU), and T. forsythia count (0.59 ± 0.04 × 10² CFU) as compared with group A (p < 0.05). Conclusion: RB-mediated a-PDT as an adjunct to SRP was significantly more effective in improving GI, PPD, and CAL and in reducing microbial count as compared with SRP alone in the management of chronic periodontitis.

Objective: This study aims to enhance the precision of implant cavity preparation, addressing a notable challenge in the current state of the field by utilizing femtosecond lasers. Background: The application of femtosecond lasers in implant cavity preparation heralds a noninvasive and efficient technique, characterized by diminished thermal damage and high biocompatibility. Despite these promising attributes, the realization of precise cavity preparation remains a significant challenge in the contemporary domain. Materials and Methods: Our research group devised a specialized femtosecond laser microsurgery robotic system tailored for sophisticated implant cavity preparation. This system facilitated the meticulous analysis of sheep shank bone samples, enabling precise three-dimensional cutting. The analysis included an extensive examination of ablation effects, using a laser scanning microscope and VK Analyzer software. This investigation spanned the phases of laser flux calibration and experimental validation, offering a critical evaluation of the automated preparation process. Results: The study delineated that at the focus position of our custom-made oral clinical femtosecond laser microsurgery robotic system, the laser spot diameter is 75.69 μm, and ascertained the ablation threshold for sheep shank cortical bone to be 1.47 J/cm². Utilizing low laser flux with minimal ablation craters overlap compromised the sidewall precision of the implant cavity, whereas employing high laser flux with extensive ablation craters overlap resulted in an enlarged ablation angle. At a laser energy setting of 2.2362 J/cm² and a 50% ablation crater overlap, an implant cavity was successfully crafted featuring a top diameter of 4.41 mm, a bottom diameter of 3.98 mm, and a depth of 3 mm, devoid of any adverse thermal effects such as cracking or carbonization. Conclusions: The oral clinical femtosecond laser microsurgery robotic system can achieve automated and precise implant cavity preparation. This advancement promotes the broader application of femtosecond lasers in the field of orthopedics.

Objective: To investigate the effects of photobiomodulation therapy (PBMT) at 660 and 810 nm on amyloid-beta (Aβ)42-induced toxicity in differentiated SH-SY5Y cells and to assess its impact on Aβ42 accumulation and cholinergic neurotransmission. Background: Alzheimer's disease (AD) is characterized by the accumulation of Aβ peptides, leading to neurodegeneration, cholinergic deficit, and cognitive decline. PBMT has emerged as a potential therapeutic approach to mitigate Aβ-induced toxicity and enhance cholinergic function. Methods: Differentiated neurons were treated with 1 μM Aβ42 for 1 day, followed by daily PBMT at wavelengths of 660 and 810 nm for 7 days. Treatments used LEDs emitting continuous wave light at a power density of 5 mW/cm² for 10 min daily to achieve an energy density of 3 J/cm². Results: Differentiated SH-SY5Y cells exhibited increased Aβ42 aggregation, neurite retraction, and reduced cell viability. PBMT at 810 nm significantly mitigated the Aβ42-induced toxicity in these cells, as evidenced by reduced Aβ42 aggregation, neurite retraction, and improved cell viability and neuronal morphology. Notably, this treatment also restored acetylcholine levels in the neurons exposed to Aβ42. Conclusions: PBMT at 810 nm effectively reduces Aβ42-induced toxicity and supports neuronal survival, highlighting its neuroprotective effects on cholinergic neurons. By shedding light on the impact of low-level light therapy on Aβ42 accumulation and cellular processes. These findings advocate for further research to elucidate the mechanisms of PBMT and validate its clinical relevance in AD management.