Photobiomodulation, photomedicine, and laser surgery最新文献

Objective: Investigate the effects of transcranial plus intranasal photobiomodulation (PBM) treatment on cognitive function, using an 810 nm light emitting diode headset and intranasal applicator every other day for 8-10 weeks. Background Data: An effective gold standard for the rehabilitation of repetitive head acceleration events (RHAEs) does not yet exist. Methods: Forty-four participants with a history of RHAEs completed a battery of cognitive tests before and after PBM treatment. Data were analyzed at the group level (paired samples t-tests, controlling for multiple comparisons) and on the individual-person level (reliable change indices). Results: On a group level, participants demonstrated statistically significant improvements with moderate-to-large effect sizes in fluid cognition, verbal learning and memory, attention and working memory, and aspects of executive function following PBM treatment. Specific improvements were observed in verbal learning/encoding and delayed recall, sustained attention, errors of omission and commission, working memory, inhibition, and cognitive switching. On the individual level, 0-36% of participants showed reliable improvement across cognitive measures, depending on the subtest; changes were greatest on measures of attention and memory. Conclusions: Results suggest that PBM treatment may be a promising intervention for improving cognitive function in individuals with a history of RHAEs. Observed improvements in cognitive function following PBM treatment may have important implications for the prevention and treatment of cognitive impairments associated with RHAEs. Further studies with more robust research designs that utilize clinical trial methodologies are needed to confirm and extend these findings.

Background: Transcranial photobiomodulation (tPBM) is a promising noninvasive neuromodulation modality with potential therapeutic benefits for neurodegenerative diseases. Infrared light delivered by a tPBM device penetrates the cortex, stimulating neuronal activity by increasing mitochondrial adenosine triphosphate production and enhancing regional cerebral blood flow. Objective: This study investigated the efficacy and safety of a self-administered, at-home, wearable tPBM device for improving cognitive function in individuals with mild cognitive impairment (MCI) due to Alzheimer's disease (AD). Methods: Individuals with MCI due to AD, diagnosed according to the National Institute on Aging and Alzheimer's Association criteria, with a Korean version of Mini-Mental State Examination-2 (K-MMSE2) score of 23-27 and a global Clinical Dementia Rating (CDR) score of 0.5-1.0 were enrolled. Subjects self-administered tPBM six times per week for 12 weeks. Assessments were conducted at weeks 7 and 13 using the Korean version of the Montreal Cognitive Assessment (K-MoCA), K-MMSE2, the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease, and the Geriatric Depression Scale. Results: A total of 26 participants were enrolled. The treatment group showed a statistically significant improvement in K-MoCA scores at week 13 (p < 0.05) compared with the sham group. Although K-MMSE2 scores improved in the treatment group, the difference was not statistically significant. No serious adverse events were reported. Conclusion: Findings suggest that tPBM is an effective and safe home-use intervention for individuals with MCI, with promising therapeutic and preventative roles in Alzheimer's dementia.

Background: Photobiomodulation (PBM), a noninvasive therapy using red and near-infrared light, has shown promising benefits in neuropathology. However, the transmission of PBM to the central nervous system through the scalp's soft tissues and skull is unknown. We hypothesize that decompressive craniectomy (DC) for moderate-to-severe traumatic brain injury (TBI) improves PBM penetrance and enhances neurorehabilitation. Method: Adult male and female Long-Evans rats were utilized to evaluate PBM tissue penetrance and its efficacy on motor deficit recovery following TBI and DC. TBI was induced using a hit-and-run closed-head model, which replicates clinical closed-head trauma. PBM transmittance was measured ex vivo using rat scalp soft tissue and hemicranium samples, with optical power and energy meter readings to quantify penetrance. Functional motor recovery was assessed using a beam walk test to quantify limb deficits defined by forelimb and hindlimb slips. Results: Analysis demonstrated attenuation of 660 nm and 850 nm PBM intensity during transcranial transmission, with scalp skin and cranial bone reducing irradiance from 70.5 mW/cm² to 3.96 mW/cm² for 660 nm PBM and from 82 mW/cm² to 4.96 mW/cm² for 850 nm PBM. Beam walk testing revealed significantly fewer hindlimb slips in PBM-treated rats (660 nm: 1.54, 850 nm: 1.86) compared with untreated TBI controls (4.3 slips), suggesting improved motor recovery. Conclusion: Our study indicates that both PBM are attenuated by both scalp soft tissues and the hemicranium, yet both penetrate sufficiently following DC for moderate-to-severe TBI. Our findings suggest that PBM enhances neurorehabilitation outcomes with improved motor recovery in rats with TBI.

Aim: To investigate the efficacy of diode laser (DL), photodynamic therapy (PDT), and ozone water on the removal of smear layer (SL) and its assessment via scanning electron microscope (SEM) following its effect on shear bond strength (SBS) on carious affected dentin. Materials and Methods: Sixty-six caries-affected dentin (CAD) samples were obtained from the dental outpatient department. The occlusal enamel and infected dentin of the included samples were meticulously excised using a water-cooled, slow-speed device, resulting in a flat mid-coronal CAD surface. Based on the effectiveness of SL removal techniques, the samples were categorized into groups (n = 11 each). Group 1: no treatment, Group 2: DL, Group 3: PDT-activated methylene blue (MB), Group 4: 16 ppm ozonated water, Group 5: 17% ethylenediamine tetra-acetic acid (EDTA), and Group 6: 37% phosphoric acid (PA). One pair of samples from each group was assessed under SEM following different conditioning regimes. The remaining samples underwent the application of an adhesive 7th-generation single-bottle adhesive and composite placement. All bonded samples were aged, and SBS assessment was performed via a universal testing machine, and unbonded surfaces were assessed under a stereomicroscope. A one-way analysis of variance was employed, followed by Tukey honestly significant difference (HSD) post hoc tests. Statistical significance was established at a p value of less than 0.05. Results: The highest SL removal efficiency was observed in the PA group. The lowest SL removal efficacy was examined in the no-treatment group. SL removal efficiency via DL and EDTA was found to be comparable (p > 0.05) and significantly lower than samples conditioned with PA (p < 0.05). Samples conditioned with PDT-activated MB and ozonated water had comparable micro (μ)- SBS scores (p > 0.05). Samples conditioned via EDTA, PA, and diode demonstrated cohesive failure predominantly. Conclusions: PA is considered the benchmark for effectively removing the SL from dentin affected by caries, as it also enhances bonding strength. Nonetheless, EDTA and DLs present viable alternatives to phosphoric acid.

Background: Photobiomodulation (PBM) is a well-established, noninvasive therapeutic modality supported by a robust scientific foundation and extensive case studies. Objectives: However, in recent years, researchers have reported that low-intensity light could also help slow down degenerative processes resulting from unbalanced or epigenetically exacerbated aging. Methods: We present data that support the use of PBM in addressing some of the primary degenerative diseases that significantly impact patients' quality of life. Results: Chronic diseases highlight the importance of emerging approaches utilizing low-power light sources, whether applied locally, systemically, or remotely. Conclusions: We conclude that PBM holds significant promise for patients suffering from chronic and debilitating conditions, offering potential therapeutic benefits. As the science of biophotonic continues to evolve, further advancements in light-based therapies are expected to enhance healing processes and improve the quality of life for patients worldwide. The growing body of evidence suggests that PBM is well-prepared to face the challenges imposed by degenerative diseases.

Objective: This study aimed to evaluate the clinical efficacy of 980 nm diode laser therapy as an adjunct to conventional treatment for acute pericoronitis. Materials and Methods: This retrospective study analyzed 108 patients with acute pericoronitis treated between June 2022 and June 2024. Participants were stratified into two groups: laser group (n = 69; 33 males, 36 females; mean age: 26.55 ± 6.05 years) and control group (n = 39; 20 males, 19 females; mean age: 26.08 ± 5.63 years). All patients initially underwent alternating irrigation with 0.9% NaCl and 3% H₂O₂ in pericoronal pockets, accompanied by oral hygiene instruction. The laser group was exposed to a 980-nm diode laser (Denlas-10BM; Wuhan Gigaa Optronics Technology Co. Ltd., China) irradiation at 1.5 W power with a 400-μm fiber tip, delivering 30-sec irradiation to the buccal, lingual, and occlusal aspects of inflamed pericoronal tissues, respectively, in combination with conventional therapy. The control group received conventional treatment alone (antibiotics, analgesics, and chlorhexidine). Clinical outcomes included maximum mouth opening (MMO), lymph node status, gingival inflammation area (GIA: Grade I-III), and pain levels assessed via visual analog scale (VAS; 0 = no pain to 10 = worst pain). Results: The laser group demonstrated significantly greater GIA improvement than controls (p < 0.05). Female patients in the control group exhibited smaller changes in GIA (p < 0.05). MMO improvement showed no intergroup difference (p > 0.05). VAS pain scores decreased from 5.49 ± 1.68 to 0.71 ± 1.59 in the laser group versus 5.54 ± 1.63 to 1.95 ± 2.37 in controls (p < 0.05). Conclusions: The 980 nm diode laser, as an adjunct to conventional therapy, provides significant benefits in treating acute pericoronitis, reducing inflammation, alleviating pain, and promoting faster recovery. This minimally invasive treatment shows promise as an effective option in dental practice.

Objective: Bone defects present a significant clinical challenge, often requiring surgical intervention due to delayed healing. Terahertz (THz) radiation, a noninvasive physical energy-based therapy, has shown potential in promoting bone regeneration through biomolecular interactions. This study aims to evaluate the therapeutic efficacy of THz irradiation in enhancing bone repair using a pre-clinical rat tibial fracture defect model. Methods: A standardized tibial bone defect model was created in rats, with daily THz irradiation (0.1 THz, 20 min/session) administered continuously for 28 days. Micro-computed tomography (CT) evaluations were performed weekly throughout the study period, while histological assessments (hematoxylin and eosin [HE] and Masson staining), vascular endothelial growth factor (VEGF) immunohistochemistry, and serum biomarker analyses were exclusively conducted at the 28-days endpoint. Micro-CT imaging, histopathological staining, and tyramide signal amplification analyses were conducted to assess bone volume fraction, collagen deposition, and angiogenesis. Blood biochemical markers were also evaluated to determine systemic metabolic effects. Results: By week 4, the THz-treated group demonstrated a higher new bone formation compared with control group. Micro-CT analysis revealed significantly improved cortical continuity and bone volume fraction at weeks 3 and 4 (p < 0.05). HE and Masson staining showed enhanced collagen alignment and trabecular organization. The IF test indicated increased VEGFA expression in local new bone (p < 0.01), suggesting augmented angiogenesis. No significant changes were observed in serum biochemistry markers, indicating localized rather than systemic effects. Conclusions: THz radiation effectively accelerates bone defect healing by enhancing osteoblast activity and vascularization without systemic metabolic alterations. These findings highlight the potential of THz therapy as a novel, noninvasive approach for bone regeneration, warranting further research for clinical translation.

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.