Photobiomodulation, photomedicine, and laser surgery最新文献

Objectives: This study evaluated in vitro the antimicrobial efficacy and penetration depth of acai as a photosensitizer (PS) using or not using passive ultrasonic irrigation (PUI). Background: Acai extracts have attracted attention as potential photosensitizing molecules, especially because of their natural origin. Methods: A total of 150 mandibular molars were instrumented with the ProTaper Next system. Ninety canals were inoculated with standard strains of Enterococcus faecalis for 21 days and randomly divided into six groups (n = 15): AC: acai; MB: methylene blue; BL: blue laser irradiation; RL: red laser irradiation; AC+BL: acai irradiated with blue laser; and MB+RL: methylene blue irradiated with red laser. Microbiological samples were collected from the canals before (no treatment group) and after the procedures described for each group. Dentinal tubule penetration was assessed in the remaining 60 canals, randomly divided into four groups (n = 15): MB; MB+PUI; AC; and AC+PUI. The PSs MB and acai were placed into the canals and agitated or not with an ultrasonic tip. The roots were sectioned and analyzed under a stereomicroscope. The results were analyzed using the Kruskal-Wallis test and analysis of variance (Tukey's test). Results: The greatest reduction in microbial counts occurred in the MB+RL, AC+BL, and AC groups (p < 0.0001). The amount of bacteria after the procedures in log colony forming units (CFU)/mL was MB+RL: 3.59, AC+BL: 5.32, and AC: 5.24. There was no significant difference in penetration depth between MB and acai, using or not using PUI, in the coronal, middle, or apical thirds (p > 0.05). Conclusion: Acai can be used as an antimicrobial agent for disinfection of the root canal, showing similar results when photoactivated or not.

Objective: Sciatic nerve injury (SNI) is a complex neurological disease, and its occurrence and development are closely related to the apoptosis signaling pathway. The mechanism of platelet-rich plasma (PRP) combined with a low-frequency pulsed electromagnetic field (LFPEMF) regulating apoptosis has not been fully elucidated. Materials and Methods: The SNI gene chip dataset GSE172064 and data from sham (n = 3) and SNI (n = 3) rats were downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) in the SNI and sham groups were identified with the online tool GEO2R. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to analyze the functional and pathway enrichment of genes in the most important modules. A SNI rat model induced by sciatic nerve crush treatment was established. PRP was injected into the severed end of nerve sutures combined with LFPEMF treatment in SNI rats for 8 weeks. Neuronal regeneration was determined via hematoxylin-eosin (HE) and Nissl staining. The protein levels of the adenosine monophosphate-activated protein (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway and apoptosis markers were detected through quantitative real-time-PCR and immunohistochemistry. Results: This study identified 255 DEGs, including 119 upregulated genes and 136 downregulated genes. GO enrichment and KEGG analyses were performed on the DEGs and revealed functional enrichment mainly in the AMPK/mTOR signaling pathway. Further, the number of Nissl bodies was significantly greater in SNI rats treated with PRP+LFPEMFs than in control rats. The immunohistochemistry results revealed significantly decreased levels of Bax and caspase-3 in the sciatic nerve regions of SNI rats treated with PRP+LFPEMFs. In addition, the Bcl-2 level was increased in SNI rats stimulated with PRP+LFPEMFs. Conclusions: Therefore, this study suggests that PRP combined with LFPEMF treatment inhibits apoptosis in the sciatic nerve during the onset of crush injury by regulating the AMPK/mTOR signaling pathway, thereby promoting neuronal regeneration and potentially serving as a therapeutic strategy for SNI.

Background: First responders are often exposed to many physically and mentally stressful events throughout their careers, and common complaints include poor sleep quality, chronic pain, post-traumatic stress symptoms, mood dysregulation, and cognitive impairments. Objective: We performed an open protocol, active treatment-only study with a small sample of male firefighters (n = 16) to examine the effects of transcranial photobiomodulation (PBM) on self-reported symptom measures and objective measures of cognitive function. Methods/Materials and Methods: The treatment consisted of 810 nm near-infrared light to the head using four transcranial LEDs and one intranasal LED. Treatment duration was 20 min per session, 3-4 sessions per week for 8 weeks. Results: We found significant pre-/post-treatment improvements with moderate-to-large effect sizes in mood and post-traumatic stress symptoms, pain interference, and readiness for social reintegration, and across all measures of fluid cognition. Conclusions: This proof-of-concept study also demonstrated no significant side effects, good compliance, and feasibility of use in a first responder population. Though additional research is required, PBM may present a relatively cost-effective, well-tolerated, low-risk, and easy-to-use treatment to enhance both specific symptoms and general wellness.

Objective: To critically assess the preventive and rehabilitative effects of photobiomodulation (PBM) on orthodontically induced root resorption (OIRR). Methods: Six databases (PubMed, Embase, Cochrane, Web of Science, Scopus and OpenGrey) were electronically searched up to September 12, 2024 to retrieve animal studies about PBM and OIRR. The risk of bias (ROB) of included studies was assessed by the SYRCLE's tool. The effects of PBM on OIRR are regarded as OIRR prevention and OIRR rehabilitation by irradiation during or after orthodontic tooth movement. The PBM protocols for reducing and rehabilitating OIRR were summarized separately. Results: A total of 15 studies were ultimately included in this review. Regarding OIRR rehabilitation, all 4 relevant studies confirmed that laser significantly reduced root resorption degree, root resorption area (RRA) and root resorption volume, respectively. As for 13 studies investigating OIRR prevention, 9 studies (5 involving laser and 4 involving light-emitting diode [LED]) supported the positive effects of PBM, 3 studies (2 involving laser and 1 involving LED) showed no effects, 1 study reported that laser irradiation increased RRA and LED did no effect. 10 studies ranked unclear ROB and 5 studies presented high ROB. Due to considerable clinical and statistical heterogeneity among included studies, the meta-analysis was not performed. Conclusion: Within current evidence of animal studies, laser-based PBM might be promising to rehabilitate OIRR. Considerable controversy still exists on the preventive effect of PBM on OIRR. Further study is needed to detect effective dose and irradiation methods of PBM on OIRR prevention.

Background: There has been an increase in interest in using in-office cosmetic treatments to promote collagen in the skin and deeper tissues. Aim: The current study assesses the safety and efficacy of the combination of a 675 nm laser wavelength and the injection of soft tissue fillers based on hyaluronic acid (HA) during facial rejuvenation treatments. Materials and methods: A total of 16 patients treated for facial skin rejuvenation and reduction of facial laxity were divided into two groups: Group 1 underwent three sessions of a 675 nm laser system combined with three sessions of HA filler and Group 2 received three sessions of the 675 nm laser system alone. One treatment every 30 days for 3 months was performed. Images were acquired at baseline (T₀), after the second session (T_m), and 1 month after the last treatment (T_f). A dermal analysis system was employed for skin analysis. The 10-point visual analog scale and the 5-point Global Aesthetic Improvement Scale (GAIS) were used. Results: In both groups, but more promisingly in Group 1, the skin showed an improvement in its elasticity reported with an increase in Young's modulus, a decrease in retraction time, and an increase in viscoelasticity. Qualitative analysis of high-frequency dermal ultrasound images showed significant increases in new collagen density and dermal thickness. These results were confirmed with the GAIS. No side effects were recorded. Conclusion: The findings indicate that the combination of 675 nm laser and HA filler was well-tolerated and safe and has shown promising results for treating skin aging.

Background: Melasma is a cutaneous pigmentary condition, difficult to treat due to its multifactorial chronic nature and high recurrence rates. Objective: To investigate the medium-term and long-term efficacy of the 675 nm laser for the treatment of facial melasma with pigmentary and vascular symptoms. Methods: Eight patients with facial melasma and Fitzpatrick phototypes III to IV were recruited. Three sessions were carried out with a 675-nm laser device. At 5 months and 12 months after the last treatment, the patient's skin was evaluated from baseline using a five-point Global Aesthetic Improvement Scale (GAIS). Results: The study findings revealed a better overall appearance of the skin condition, in particular GAIS improvements mainly in the visible and pigmented components. Conclusion: The 675-nm laser appears to be effective when treating patients with Fitzpatrick phototypes III to IV for facial melasma, with promising long-term results.

Objective: This study assessed the impact of a 5% combination of 5-aminolevulinic acid (5-ALA) (Aladent) in a multispecies in vitro biofilm model subgingival pathogens. Methods: The 33-species biofilm model was established in the Calgary Biofilm Device during a duration of 7 days. The biofilm treatments comprised various groups: control, light-emitting diode (LED), Aladent (ALADA), and Aladent with LED (ALAD+L), administered on day 6. The Aladent was in contact with the biofilm for 45 min before to the 7-min LED treatment. The LED (λ = 630 nm, power ≈ 380 mW/cm²) was placed 2 mm from the biofilm. Subsequently, during 7 days of biofilm formation, the metabolic activity of the biofilms was assessed utilizing triphenyltetrazolium chloride, and the presence of 33 bacterial species was evaluated through DNA-DNA hybridization. Results: The findings indicated that the ALAD+L treatment was the sole intervention demonstrating a statistically significant reduction (∼70%) in the metabolic activity of the biofilms relative to the control group. Moreover, ALAD+L markedly diminished the overall biofilm count and the average counts of five bacterial species: S. intermedius, V. parvula, A. israelii, P. gingivalis, and E. saburreum. Conclusion: The integration of the photosensitizer Aladent with LED application significantly diminished metabolic activity and bacterial species count in the multispecies subgingival biofilm model, indicating substantial promise for the treatment of peri-implantitis.

Background: Commercial lasers and light combs have limitations such as restricted wavelengths, inconsistent energy delivery, and variable results. While photobiomodulation therapy (PBMT) at 650 nm has been extensively studied for hair growth, research on PBMT at 1550 nm and 14,000 nm (far infrared radiation, FIR) remains limited. Objective: This study aims to evaluate and compare the effectiveness of PBMT, including 650 nm, 1550 nm, and 14,000 nm, in promoting hair growth and improving scalp health. Method: A controlled study with 68 participants (18-60 years old) assigned them to either PBMT 650 nm, 1550 nm, 14,000 nm, or a control group. Treatment lasts 3 months, with maintenance treatments every 4-6 weeks for up to 9 months. Hair density, scalp condition, and loss were assessed at baseline 3, 6, and 9 months. Results: PBMT at 650 nm, 1550 nm, and 14,000 all improved hair growth over 9 months. Hair density increased in the PBMT groups (100→114 hairs/cm², 99→115 hairs/cm², and 101→107 hairs/cm²), while the control group declined (100→98 hairs/cm²). Among the 68 participants, 42 had oily scalps initially. This condition improved in all treatment groups, with oily scalp cases nearly halved in each treatment group. Conclusion: PBMT (650 nm, 1550 nm, and 14,000 nm) effectively promotes hair growth and reduces hair loss. Further research is needed to refine protocols, explore combinations, and extend follow-up periods.

Background: Rhinophyma, an advanced form of rosacea, primarily affects older men and is characterized by nasal hypertrophy and irregular surface texture. Traditional treatments include pharmacologic interventions and various surgical techniques. Objective: To present the clinical outcome of a novel combined treatment using fractional carbon dioxide laser (FCL) and fractional microneedle radiofrequency (FmRF) in a patient with rhinophyma. Methods: A 62-year-old male with prominent nasal seborrhea, hypertrophy, and surface irregularities underwent combined treatment with FCL and FmRF. The treatment sessions were performed under topical anesthesia with post-procedure care including emollients and sun protection. Results: The patient experienced marked cosmetic improvement, including reduced nasal bulk and smoother surface texture, without adverse events such as scarring or pigmentary alteration. The recovery period was short, and patient satisfaction was high. Conclusions: This case represents the first report of combining FCL and FmRF for the treatment of rhinophyma. The favorable clinical and cosmetic outcome suggests this method may be a promising alternative to conventional surgical approaches. Further studies are needed to validate its efficacy and safety in broader populations.

Aim: This investigation aimed to assess the efficacy of reversal methods on bleached enamel via fluoride-activated Er:YAG, diode, femtosecond laser, focusing on Vickers hardness (VH), shear bond strength (SBS), calcium (Ca⁺⁺)/phosphorus (P) ratio, and the interface between brackets and enamel. Materials and Methods: A total of 112 human maxillary premolars with intact enamel, which had been extracted, were included. About 96 specimens underwent bleaching using a 40% hydrogen peroxide (HP) Office bleaching agent. The remaining 16 samples were taken as control. The enamel samples were divided into six groups (2-7) based on the bleaching reversal technique (n = 16). Samples in Group 1 contained unbleached samples of sound enamel (n = 10). Group 1: Samples did not undergo bleaching; Group 2: bleached samples with no reversal; Group 3: bleached enamel reversal via fluoride activated by Er:YAG laser; Group 4: bleached enamel reversal via fluoride activated by diode laser; Group 5: bleached enamel reversal via fluoride activated by femtosecond laser; Group 6: bleached enamel reversal via Na-Ascorbate; and Group 7: bleached enamel reversal with fluoride. From controls and interventional groups, two pairs of samples were assessed for VH and one pair of samples for EDX to assess Ca/P. All samples were bonded with brackets for SBS assessment and bracket-enamel interface. Analysis of variance, followed by post hoc multiple comparison tests, was used to tabulate results for SBS, VH, and the Ca/P ratio. Results: Ca/P ratio, VH, and SBS in bleached enamel reversed via Er:YAG laser + fluoride and femtosecond laser + fluoride demonstrated the efficacy of reversal similar to bleached enamel reversed by a conventional method, Na-Ascorbate, and control. Conclusions: Fluoride-treated bleached enamel, activated via Er, YAG, or femtosecond lasers, was effective in reversing the undesirable effects of bleaching, improving SBS of orthodontic brackets, Ca/P ratio, and enamel hardness.