Effects of laser irradiation on the release of basic fibroblast growth factor (bFGF), insulin like growth factor-1 (IGF-1), and receptor of IGF-1 (IGFBP3) from gingival fibroblasts

Antiproliferative effect of low-level laser/ photobiomodulation on gingival fibroblasts derived from calcium channel blocker-induced gingival overgrowth

The aim of this study was to evaluate the antiproliferative properties of low-level laser therapy (LLLT) on gingival fibroblasts obtained from calcium channel blocker-induced gingival overgrowth (GO). Gingival fibroblasts of patients with GO were compared to healthy gingival fibroblasts (H). Both cells were exposed to LLLT (685 nm wavelength, 25mW power, diode laser) and compared to those not treated with LLLT. Cell proliferation and viability were measured with MTT assay at baseline and after 24 and 72 h. TGF-β1, CTGF, and collagen Type 1 levels were evaluated with Enzyme-Linked Immunosorbent Assay (ELISA). LLLT significantly decreased the proliferation of GO fibroblasts (p < 0.05) while leading to a significantly higher proliferation in H fibroblasts compared to the untreated cells (p < 0.05). GO cells showed significantly higher CTGF, TGF-β, and collagen Type 1 expression than the H cells (p < 0.05). LLLT significantly reduced CTGF levels in GO cells compared to the control group (p < 0.05). In H cells, CTGF and TGF-β levels were also significantly decreased in response to LLLT compared to the control group (p < 0.05). While LLLT significantly reduced collagen expression in the H group (p < 0.05), it did not significantly impact the GO cells. LLLT significantly reduced the synthesis of the growth factors and collagen in both groups with an antiproliferative effect on the gingival fibroblasts from calcium channel blocker-induced GO, suggesting that it can offer a therapeutic approach in the clinical management of drug-induced GO, reversing the fibrotic changes.

Clinical efficacy and pain control of diode laser-assisted flap surgery in the treatment of chronic periodontitis:A systematic review and meta-analysis

Objective

To assess the diode laser-assisted periodontal flap surgery's clinical effectiveness and postoperative pain management in treating chronic periodontitis, and to offer evidence-based medical justification for the procedure's clinical use.

Data sources and study selection

In this study, a computer combined with manual search was used to search for articles on diode laser-assisted periodontal flap surgery for the treatment of chronic periodontitis published from the establishment of the database to September 2023. The databases searched included China Academic Journal Full Text Database (CNKI), China Biomedical Literature Database (CBM), Chinese Science and Technology Journal Database (VIP), Wanfang Database, PubMed, Web of science, Cochrane Library, Embase, and Scopus. Two researchers independently performed the screening and study selection, following the inclusion and exclusion standards to extract basic information and required data. Meta-analysis of the included literature was performed using Revman V5.4 software.

Result

Thirteen articles were analyzed. Meta-analysis showed that the use of the diode laser was effective in reducing patients' probing pocket depth (PPD) at 3 and 6 months postoperatively (3 months: MD = -0.46, 95 % CI = [-0.89, -0.03], P = 0.04; 6 months: MD = -0.35, 95 % CI = [-0.63, -0.06], P = 0.02), was able to effectively improve 3 month clinical attachment level (CAL) (MD = -0.36, 95 % CI = [-0.66, -0.06], P = 0.02), and was able to promote wound healing and reduce patients' early postoperative pain (MD = 0.67, 95 % CI = [0.01, 1.32], P = 0.05; MD = -1.67, 95 % CI = [-2.23, -1.00], and P < 0. 001), while for gingival index (GI), the use of diode laser did not have a significant effect.

Conclusions

The available evidence suggests that the use of a diode laser adjunct is effective in reducing PPD, improving CAL, promoting wound healing, and reducing early postoperative pain in patients compared with flap application alone; however, for GI, diode lasers did not show any improvements.

Clinical significance

Periodontal flap surgery fails to eliminate microorganisms from the soft tissue wall, potentially leading to recolonization, reinfection, and accompanying side effects such as pain and swelling. The use of a diode laser reduces PPD, improves CAL, and relieves early postoperative pain.

Effects of low-level Er:YAG laser irradiation on proliferation and gene expression in primary gingival fibroblasts isolated from mouse maxilla

We investigated the effects of low-level Er:YAG laser irradiation on proliferation and alternations in early gene expression of gingival fibroblasts. Mice primary gingival fibroblasts were irradiated with an Er:YAG laser (1.8, 3.9, and 5.8 J/cm2 ). Irradiation at 3.9 J/cm2 promoted cell proliferation without significant changes in lactate dehydrogenase or Hspa1a expression. Three hours after irradiation at 3.9 J/cm2 , the Fn1 expression level was significantly increased. RNA-seq identified 15 differentially expressed genes between irradiated and non-irradiated cells, some of which belonged to immediate early genes (IEGs). Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated MAPK pathway enhancement, and gene set enrichment analysis showed enrichment in the TGF-β signaling gene set. Enhanced proliferation via laser irradiation disappeared upon inhibition of Dusp4, Dusp5, and Tgfr1 expression. Low-level Er:YAG laser irradiation, especially at 3.9 J/cm2 without a major temperature elevation, enhanced fibroblast proliferation, via TGF-β and the MAPK signaling pathway following IEG expression.

Radioreparative Effect of Diode Laser on Leukopoiesis Recovery: A Pilot Study

The aim of the present study was to investigate the effect of laser therapy on leukopoiesis recovery after irradiation with ionizing radiation. A dose of ionizing radiation was used that induced the hematological form of radiation sickness, reducing the number of blood cells. Subsequently, mice were treated with non-ionizing laser radiation. Based on the examination of the peripheral blood, the study found that laser therapy significantly impacted the number of eosinophils and basophils two weeks after irradiation. Laser therapy also led to the faster reparation of the lymphocyte lineage of white blood cells (WBCs). The research showed that the examined therapeutic laser had a long-term radioreparative effect on gamma-irradiated mice, improving the absolute counts of different lines of WBCs. The results of this study could have implications for the treatment of radiation sickness in humans.

Enhancing osteogenic differentiation in adipose-derived mesenchymal stem cells with Near Infra-Red and Green Photobiomodulation

Worldwide, osteoporosis is the utmost predominant degenerative bone condition. Stem cell regenerative therapy using adipose-derived mesenchymal stem cells (ADMSCs) is a promising therapeutic route for osteoporosis. Photobiomodulation (PBM) has sparked considerable international appeal due to its' ability to augment stem cell proliferation and differentiation properties. Furthermore, the differentiation of ADMSCs into osteoblast cells and cellular proliferation effects have been established using a combination of osteogenic differentiation inducers and PBM. This in vitro study applied dexamethasone, β-glycerophosphate disodium, and ascorbic acid as differentiation inducers for osteogenic induction differentiation media. In addition, PBM at a near-infrared (NIR) wavelength of 825 nm, a green (G) wavelength of 525 nm, and the novel combination of both these wavelengths using a single fluence of 5 J/cm2 had been applied to stimulate proliferation and differentiation effectivity of immortalised ADMSCs into early osteoblasts. Flow cytometry and ELISA were used to identify osteoblast antigens using early and late osteoblast protein markers. Alizarin red Stain was employed to identify calcium-rich deposits by cells within culture. The morphology of the cells was examined, and biochemical assays such as an EdU proliferation assay, MTT proliferation and viability assay, Mitochondrial Membrane Potential assay, and Reactive Oxygen Species assay were performed. The Central Scratch Test determined the cells' motility potential. The investigative outcomes revealed that a combination of PBM treatment and osteogenic differentiation inducers stimulated promising early osteogenic differentiation of immortalised ADMSCs. The NIR-Green PBM combination did appear to offer great potential for immortalised ADMSC differentiation into early osteoblasts amongst selected assays, however, further investigations will be required to establish the effectivity of this novel wavelength combination. This research contributes to the body of knowledge and assists in the establishment of a standard for osteogenic differentiation in vitro utilising PBM.

The use of low level laser therapy in conjunction with diode laser-assisted and conventional vestibuloplasty: Comparison of wound healing and vestibular depth gain

BACKGROUND

The aim of this study is to compare wound healing and vestibular depth gain in individuals undergoing vestibule deepening surgery using diode laser and conventional technique and to further investigate the possible wound healing effect of low-level laser therapy (LLLT).

MATERIAL AND METHODS

52 systemically healthy individuals with insufficient vestibular depth in the region of teeth 33-43 in the lower jaw were included. Following nonsurgical periodontal treatment, patients were divided into four groups as follows: a) diode laser (L); b) diode laser + LLLT; c) conventional surgery and d) conventional surgery + LLLT. Vestibular depth and horizontal wound size measurements of the individuals were recorded using digital calipers. Reepithelization was evaluated via an image analysis program.

RESULTS

Vestibular depth measurements were found to be higher in the conventional surgery groups compared to that of diode laser groups after the operation, while the results were not statistically different between groups (p >0.05). Reepithelization area did not differ between groups in the evaluated time periods (p >0,05). On the other hand, horizontal wound shrinkage was significantly higher in the conventional surgery group than that of diode laser.

CONCLUSIONS

Within the limits of this study, both methods yielded in vestibule depth gain. On the other hand, LLLT did not have an additional positive effect on mucosal wound healing. As a clinical relevance, the results are valuable for clinicians in terms of showing that suturing of the mucosal flap formed following vestibule deepening should not be necessary in laser assisted surgery for attaining more vestibule depth.

Photobiomodulation therapy assisted orthodontic tooth movement: potential implications, challenges, and new perspectives

Over the past decade, dramatic progress has been made in dental research areas involving laser therapy. The photobiomodulatory effect of laser light regulates the behavior of periodontal tissues and promotes damaged tissues to heal faster. Additionally, photobiomodulation therapy (PBMT), a non-invasive treatment, when applied in orthodontics, contributes to alleviating pain and reducing inflammation induced by orthodontic forces, along with improving tissue healing processes. Moreover, PBMT is attracting more attention as a possible approach to prevent the incidence of orthodontically induced inflammatory root resorption (OIIRR) during orthodontic treatment (OT) due to its capacity to modulate inflammatory, apoptotic, and anti-antioxidant responses. However, a systematic review revealed that PBMT has only a moderate grade of evidence-based effectiveness during orthodontic tooth movement (OTM) in relation to OIIRR, casting doubt on its beneficial effects. In PBMT-assisted orthodontics, delivering sufficient energy to the tooth root to achieve optimal stimulation is challenging due to the exponential attenuation of light penetration in periodontal tissues. The penetration of light to the root surface is another crucial unknown factor. Both the penetration depth and distribution of light in periodontal tissues are unknown. Thus, advanced approaches specific to orthodontic application of PBMT need to be established to overcome these limitations. This review explores possibilities for improving the application and effectiveness of PBMT during OTM. The aim was to investigate the current evidence related to the underlying mechanisms of action of PBMT on various periodontal tissues and cells, with a special focus on immunomodulatory effects during OTM.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Effectiveness of photobiomodulation with low-level lasers on the acceleration of orthodontic tooth movement: a systematic review and meta-analysis of split-mouth randomised clinical trials

Although several studies have evaluated the effect of low-level laser therapy (LLLT) on orthodontic movement acceleration, results are still inconsistent. Such inconsistencies may be attributed to the differences in the LLLT application protocols, especially in terms of wavelength ranges. Objective: (i) to assess the clinical effects of LLLT on the acceleration of orthodontic movement and (ii) to establish the most effective LLLT wavelength to accelerate tooth movement during orthodontic treatments. MEDLINE (PubMed), Scopus, ScienceDirect, and LILACS were searched from inception to October 2022. Inclusion criteria: Split-mouth randomised clinical trials (RCTs) on systemically healthy patients reporting the effect of LLLT in accelerating orthodontic movements, specifically retraction of canines. The risk of bias was assessed using RoB-2. A random effect model was applied. Nineteen RCTs met the inclusion criteria for qualitative synthesis, and eighteen RCTs were included in the quantitative synthesis. Seventeen studies were rated as at some concerns of bias and two studies were classified as having a low risk of bias. In general terms, this systematic review and meta-analysis presents a moderate risk of bias. Findings of this systematic review and meta-analysis point to a tendency for faster orthodontic dental movement in the groups receiving LLLT treatment during the first (OR of 0.28 95% CI (0.07 to 0.48)), second (OR of 0.52 95% CI (0.31 to 0.73)), and third (OR of 0.41 95% CI (0.03 to 0.79)) month follow-up. Wavelengths ≤ 810 nm and energy density values ≤ 5.3 J/cm2 were associated with faster orthodontic tooth movement.

Investigation of Igf-1, Igf-Bp3 and Igf-Bp5 levels in umbilical cord blood of infants with developmental dysplasia of the hip

BACKGROUND

IGF-1 (insulin-like growth factor-1) is an important regulator of bone formation. Its deficiency has been associated with fetal growth disorders and hip dysplasia. The aim of this study was to evaluate whether IGF-1, IGF-BP3 (insulin like growth factorbinding protein 3), and IGF-BP5 levels in the umbilical cord blood can be predictive for early diagnosis of DDH.

METHODS

Umbilical cord blood samples were collected from 860 mothers with pregnancies at high risk for DDH between October 2020 and January 2021. Mothers at 37-42 weeks of gestation, with risk factors for DDH, who delivered healthy infants were included. Blood samples were collected during delivery. Each eligible infant was medically followed up and underwent a hip ultrasound in the postnatal 2nd or 3rd month. Infants diagnosed with DDH were matched with a healthy cohort in terms of sex, birth weight, maternal age, and gestational week, and the IGF-1, IGF-BP3 and IGF-BP5 levels were studied and compared.

RESULTS

Evaluation was made of 20 infants diagnosed with DDH and 60 healthy infants. Of the total 80 infants, 72.5% were female.The umbilical cord blood levels of IGF-1 and IGF-BP3 were similar in both groups. The IGF-BP5 values were significantly lower in the DDH patient group. Except for DDH diagnosis, the other categorical variables of the study did not appear to influence the levels of any of the IGFs.

DISCUSSION

Umbilical blood samples could potentially help diagnose DDH. The levels of IGF-BP5 were shown to be significantly lower in infants with DDH.

Unveiling the m6A Methylation Regulator Links between Prostate Cancer and Periodontitis by Transcriptomic Analysis

Objective

To identify the N6-methyladenosine (m6A) methylation regulator genes linking prostate adenocarcinoma (PRAD) and periodontitis (PD).

Materials and Methods

PD and TCGA-PRAD GEO datasets were downloaded and analyzed through differential expression analysis to determine the differentially expressed genes (DEGs) deregulated in both conditions. Twenty-three m6A RNA methylation-related genes were downloaded in total. The m6A-related genes that overlapped between PRAD and PD were identified as crosstalk genes. Survival analysis was performed on these genes to determine their prognostic values in the overall survival outcomes of prostate cancer. The KEGG pathways were the most significantly enriched by m6A-related crosstalk genes. We also performed lasso regression analysis and univariate survival analysis to identify the most important m6A-related crosstalk genes, and a protein-protein interaction (PPI) network was built from these genes.

Results

Twenty-three m6A methylation-related regulator genes were differentially expressed and deregulated in PRAD and PD. Among these, seven (i.e., ALKBH5, FMR1, IGFBP3, RBM15B, YTHDF1, YTHDF2, and ZC3H13) were identified as m6A-related cross-talk genes. Survival analysis showed that only the FMR1 gene was a prognostic indicator for PRAD. All other genes had no significant influence on the overall survival of patients with PRAD. Lasso regression analysis and univariate survival analysis identified four m6A-related cross-talk genes (i.e., ALKBH5, IGFBP3, RBM15B, and FMR1) that influenced risk levels. A PPI network was constructed from these genes, and 183 genes from this network were significantly enriched in pathogenic Escherichia coli infection, p53 signaling pathway, nucleocytoplasmic transport, and ubiquitin-mediated proteolysis.

Conclusion

Seven m6A methylation-related genes (ALKBH5, FMR1, IGFBP3, RBM15B, YTHDF1, YTHDF2, and ZC3H13) were identified as cross-talk genes between prostate cancer and PD.

Clinical application of low-level laser therapy (Photo-biomodulation therapy) in the management of breast cancer-related lymphedema: a systematic review

Background

Breast cancer-related lymphedema (BCRL) is a frequent issue that arises after mastectomy surgery in women and compromises physical and mental function. Previously published studies have shown positive effects with the use of Low-level laser therapy in another term Photo-biomodulation therapy (PBM). This research investigated the efficacy of clinical use of LLLT (PBM) in the treatment of metastatic breast cancer-related lymphedema.

Methods

PubMed, PEDro, Medline, and the Cochrane Library were searched for LLLT clinical trials published before October 2021. The methodological quality of randomized trials and the effectiveness of Laser Therapy for BCRL were evaluated. The primary objectives were arm circumference or arm volume, whereas the secondary goals were to assess shoulder mobility and pain severity.

Results

Eight clinical trials were analyzed in total. Typically, the included RCTs had good research quality. At four weeks, there was a considerable reduction in arm circumference/volume, and this continued with long-term follow-up. However, no statistically significant change in shoulder mobility or pain severity was seen between the laser and placebo groups at 0-, 1-, 2-, and 3-month short-term follow-up.

Conclusions

The findings of this comprehensive study demonstrated that LLLT (PBM) was successful in diminishing arm circumference and volume than improving shoulder mobility and pain. Data indicates that laser therapy (PBM) may be a beneficial treatment option for females with PML. Because of the scarcity of evidence, there is a strong need for well-conducted and longer-duration trials in this field.

Trial registration

Details of the protocol for this systematic review were registered on PROSPERO and can be accessed at www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42022315076.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10021-8.

In Vitro Effect of 810 nm and 940 nm Diode Laser Irradiation on Proliferation of Human Gingival Fibroblasts and Expression of Procollagen Gene

Factors promoting fibroblast proliferation and collagen synthesis can subsequently enhance wound healing. This study aimed to assess the effect of 810 and 940 nm diode laser on fibroblast proliferation and procollagen gene expression. In this study, human gingival fibroblasts were cultured in Dulbecco's modified Eagle's medium and underwent 810 and 940 nm diode laser irradiation once, twice, thrice and four times at 1, 3, 5 and 7 days after culture. The methyl thiazolyl tetrazolium assay was performed to assess the proliferation while the real-time polymerase chain reaction was performed to assess the expression of procollagen gene at the mRNA level. We applied Two-way ANOVA and Tukey's test for analysis. Wavelength had no significant effect on proliferation of gingival fibroblasts, but increasing the number of irradiation sessions of both wavelengths increased the proliferation of human gingival fibroblasts. Significant differences were noted in the number of human gingival fibroblasts between groups irradiated 1 and 4 and also 2 and 4 times. Procollagen gene was well expressed in all groups but its expression was significantly higher in 940 nm laser group after 4 irradiation cycles. 4 times radiation of 940 nm laser seems to be more effective than all others.

Efficacy of concentrated growth factor with low-level laser for the regeneration of interdental papilla defects

Gingival "black triangle" is common in clinical which due to interdental papilla recession. The cause of the loss of papilla is multi-factorial and it may be caused by the absorption of interdental alveolar bone or abnormal tooth position. Besides, it is a common complication after orthodontics and implant surgery. Recession of gingival papilla influences interdental plaque control, increasing food impaction and alveolar bone absorption, causing aesthetic and pronunciation problems. Thus, the way of reducing or eliminating the gingival "black triangle" has become one of the most essential problems for dentists. Concentrated growth factor (CGF) and low-level-laser therapy have been widely used, respectively, and CGF was considered as the only self-substance which has soft tissue regeneration function. This study aims to evaluate the efficacy of regenerating interdental papilla by Liquid phase concentrated growth factor (LPCGF) injection with low-level-laser therapy (LLLT).

Effect of diode laser as an adjunct to open flap debridement in treatment of periodontitis – A randomized clinical trial

Background:

The goals of periodontal therapy are to prevent the disease, arrest the disease progression, and regeneration of lost periodontium. Diode laser gained popularity in periodontal practice with a wide range of potential benefits.

Aim:

This study aims to evaluate and compare the clinical effects of laser-assisted open flap debridement (OFD) versus conventional OFD for the periodontitis treatment.

Materials and Methods:

A split-mouth, randomized clinical trial was conducted on fifteen participants with periodontitis having probing pocket depths (PPD) ≥5 mm. A total of 30 sites, two sites in each patient, were randomly divided into two groups. Group A received conventional OFD, and Group B received laser-assisted OFD. The assessment of PPD, relative attachment level (RAL), modified sulcular bleeding index (mSBI) was done at baseline, 3 months, and 6 months. Wound healing index (WHI) was assessed at 3^rd and 7^th day postsurgery, patient response to pain using visual analog scale (VAS) was assessed immediately, 1 day, and 1 week after surgery.

Results:

The results revealed a significant reduction in PPD, mSBI, and gain in RAL within the groups from baseline to 3 months and 6 months. Intergroup comparison showed a significant difference in PPD, RAL, mSBI, WHI and VAS scores.

Conclusions:

The use of 980 nm diode laser provided additional benefits over conventional flap therapy.

Photobiomodulation of human gingival fibroblasts with diode laser - A systematic review

Low-level laser therapy (LLLT) is being extensively studied in the field of periodontics as a noninvasive technique to achieve better results after nonsurgical and surgical therapy. However, there is a lack of definitive guidelines for the use of LLLT to promote gingival and periodontal wound healing. The primary objective of this systematic review was to critically analyze the studies evaluating the effect of low-level diode laser on human gingival fibroblasts in vitro and to develop wavelength-specific guidelines for photobiomodulation of human gingival fibroblasts. A thorough electronic and manual search was conducted for relevant articles published until December 2019. Nine studies were included in the review after the initial screening of 1334 articles. Our data analysis revealed that LLLT with diode laser stimulates human gingival fibroblasts as there was the increase in cell viability, proliferation, migration, and protein synthesis in irradiated cells. The diode lasers in the 600–700 nm spectrum were effective in the 10 mW to 30 mW power range. Lasers in the 700–800 nm range were effective in the 25–50 mW power range and diode lasers in the 800–900 nm range were effective at a power setting of 10 mW. It was possible to ascertain a suitable power setting for a particular wavelength spectrum, but no other parameters could be defined due to a lack of reporting of details. Hence, the authors have developed guidelines for comprehensive reporting of in–vitro studies to facilitate future research and overcome existing lacunae in knowledge.

Combined application of chondroitinase ABC and photobiomodulation with low-intensity laser on the anal sphincter repair in rabbit

Background

Photobiomodulation with low-intensity laser (LIL) and chondroitinase ABC (ChABC) can repair damaged muscle tissue, so the aim of this study was to investigate the effect of co-administration of these two factors on anal sphincter repair in rabbits.

Methods

Male rabbits were studied in 5 groups (n = 7): Control (intact), sphincterotomy, laser, ChABC and laser + ChABC. 90 days after intervention were evaluated resting and maximum squeeze pressures, number of motor units, collagen amount, markers of muscle regeneration and angiogenesis.

Results

Resting pressure in the Laser + ChABC group was higher than the sphincterotomy, laser and ChABC groups (p < 0.0001). Maximum squeeze pressure in the all study groups was higher than sphincterotomy group (p < 0.0001). In the laser + ChABC and ChABC groups, motor unit numbers were more than the sphincterotomy group (p < 0.0001). Collagen content was significantly decreased in the laser (p < 0.0001) and laser + ChABC groups. ACTA1 (p = 0.001) and MHC (p < 0.0001) gene expression in the Laser + ChABC group were more than the laser or ChABC alone. VEGFA (p = 0.009) and Ki67 mRNA expression (p = 0.01) in the Laser + ChABC group were more than the laser group, But vimentin mRNA expression (p < 0.0001) was less than the laser group.

Conclusion

Co-administration of ChABCs and photobiomodulation with LIL appears to improve the tissue structure and function of the anal sphincter in rabbits more than when used alone.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-02047-2.

Photobiomodulation therapy does not depend on the differentiation of dental pulp cells to enhance functional activity associated with angiogenesis and mineralization

The purpose of this study is to analyze the influence of InGaAlP diode laser (660 nm) with or without an odontogenic medium (OM) in the functional activity of OD-21 cells. Undifferentiated OD-21 pulp cells were cultivated with or without OM and divided into four groups (n = 5): nonirradiated control (C -), nonirradiated + OM (C +), irradiated (L -), and irradiated + OM (L +). Laser application was performed in two sessions of a 24-h interval with an irradiance of 11.3 mW/cm2, energy density of 1 J/cm², and total cumulative energy/well of 4.6 J. Cell proliferation, VEGF-164 expression, mineralization, and expression of Alp, Runx2, and Dmp1 genes, as well as immunolocalization of RUNX2 and MEPE proteins, were evaluated. Data were analyzed by statistical tests (α = 0.05). All studied groups showed a similar increase in cell proliferation with or without OM. After 7 and 10 days, a significatively higher concentration of VEGF-164 in L - group when compared to C - group was observed. A significant increase in mineralized nodules in the L + was noted when compared to C + in the same conditions. Photobiomodulation upregulated significantly Runx2 and Dmp1 expression after 10 days in L - and after 7 days in L + , with downregulation of Dmp1 after 10 days in L + group. Immunolocalization of RUNX2 and MEPE was expressive after 7 days of culture in the cytoplasm adjacent to the nucleus with a decrease after 10 days, regardless of the presence of OM. Photobiomodulation enhances metabolism associated with angiogenesis, gene expression, and mineralization regardless of the odontogenic medium in OD-21 cells.

Could the photobiomodulation therapy induce angiogenic growth factors expression from dental pulp cells?

This study aimed to evaluate the effect of different photobiomodulation (PBM) radiant exposures on the viability, proliferation, and gene expression of pulp fibroblasts from human primary teeth (HPF) involved in the pulp tissue repair. HPF were irradiated with Laser InGaAlP (Twin Flex Evolution, MMOptics®) at 660-nm wavelength (red); single time, continuous mode, 0.04-cm² laser tip area, and 0.225-cm laser tip diameter, keeping the distance of 1 mm between the laser beam and the cell culture. The doses used were between 1.2 and 6.2 J/cm² and were evaluated at the 6 h, 12 h, and 24 h after PBM. MTT and crystal violet assays evaluated the cell viability and proliferation. RT-PCR verified VEGF and FGF-2 mRNA expression. A blinded examiner analyzed the data through two-way ANOVA followed by Tukey test (p < 0.05). The groups with higher powers (10 mW, 15 mW, 20 mW, and 25 mW), shortest application periods (10 s), and radiant exposures between 2.5 and 6.2 J/cm² exhibited statistically higher viability than that of the groups with small power (5 mW), longer application period (50 s), and radiant exposure of 6.2 J/cm² (p < 0.05). VEGF and FGF-2 mRNA expression were observed at the three evaluated periods (6 h, 12 h, and 24 h) and the highest expression was in the shortest period (p < 0.05). All radiant exposures maintained HPF viable. The period of 6 h after irradiation showed statistically greater gene expression for both growth factors than other periods. VEGF mRNA had no differences among the dosimetries studied. The best radiant exposures for FGF-2 gene expression were 2.5 J/cm² and 3.7 J/cm².

Photobiomodulation: An Effective Approach to Enhance Proliferation and Differentiation of Adipose-Derived Stem Cells into Osteoblasts

Osteoporosis is regarded as the most common chronic metabolic bone condition in humans. In osteoporosis, bone mesenchymal stem cells (MSCs) have reduced cellular function. Regenerative medicine using adipose-derived stem cell (ADSC) transplantation can promote the growth and strength of new bones, improve bone stability, and reduce the risk of fractures. Various methods have been attempted to differentiate ADSCs to functioning specialized cells for prospective clinical application. However, commonly used therapies have resulted in damage to the donor site and morbidity, immune reactions, carcinogenic generation, and postoperative difficulties. Photobiomodulation (PBM) improves ADSC differentiation and proliferation along with reducing clinical difficulties such as treatment failures to common drug therapies and late initiation of treatment. PBM is a noninvasive, nonthermal treatment that encourages cells to produce more energy and to undergo self-repair by using visible green and red and invisible near-infrared (NIR) radiation. The use of PBM for ADSC proliferation and differentiation has been widely studied with multiple outcomes observed due to laser fluence and wavelength dependence. In this article, the potential for differentiating ADSCs into osteoblasts and the various methods used, including biological induction, chemical induction, and PBM, will be addressed. Likewise, the optimal laser parameters that could improve the proliferation and differentiation of ADSC, translating into clinical success, will be commented on.

Photobiomodulation Therapy by 820 nm Diode Laser on Nonsurgical Periodontal Treatment of Smoker and Nonsmoker Patients: A Single-Blind Parallel Randomized Clinical Trial

The effect of smoking on nonsurgical periodontal treatment (SRP) is known, but the adjunct use of photobiomodulation (PBMT) to SRP has not been fully investigated in smokers. This study aimed to assess the effect of 820 nm diode laser on SRP in smoker/nonsmoker. Sixty patients (smokers/n = 30, nonsmokers/n = 30) were enrolled in this parallel-arm clinical study. All patients were divided into two main groups: SRP and PBMT + SRP. In PMBT + SRP groups, 7.96 J cm^-2 energy was applied by 820nm diode laser at baseline and first, second and third weeks after SRP. Periodontal pocket depth (PPD), gingival index (GI), plaque index (PI) and clinical attachment level (CAL) were recorded, and also gingival crevicular fluid (GCF) samples were collected at baseline and 6w after SRP. Total antioxidant capacity (TAOC) and total oxidative status (TOS) in GCF were analyzed. PBMT + SRP groups showed a statistically significant decrease in PPD and CAL, not in GI and PI compared with SRP alone. There were no statistically significant differences between smokers and nonsmokers in clinical data at six weeks after treatment. Although TAOC levels were increased in PMBT groups, TOS levels were decreased in all groups at the comparison of baseline and 6w after SRP. Adjunct use of 820 nm diode laser on SRP may improve the clinical parameters in smoker or nonsmoker patient with periodontitis.

Assessment of Human Gingival Fibroblast Proliferation after Laser Stimulation In Vitro Using Different Laser Types and Wavelengths (1064, 980, 635, 450, and 405 nm)-Preliminary Report

PURPOSE

to assess the effect of photobiomodulation (PBM) on human gingival fibroblast proliferation.

METHODS

The study was conducted using the primary cell cultures of human fibroblasts collected from systemically healthy donors. Three different laser types, Nd:YAG (1064 nm), infrared diode laser (980 nm), and prototype led laser emitting 405, 450, and 635 nm were used to irradiate the fibroblasts. Due to the patented structure of that laser, it was possible to irradiate fibroblasts with a beam combining two or three wavelengths. The energy density was 3 J/cm2, 25 J/cm2, 64 J/cm2. The viability and proliferation of cells were determined using the (Thiazolyl Blue Tetrazolium Blue) (MTT) test conducted 24, 48, and 72 h after laser irradiation.

RESULTS

The highest percentage of mitochondrial activity (MA = 122.1%) was observed in the group irradiated with the 635 nm laser, with an energy density of 64 J/cm2 after 48 h. The lowest percentage of MA (94.0%) was observed in the group simultaneously irradiated with three wavelengths (405 + 450 + 635 nm). The use of the 405 nm laser at 25 J/cm2 gave similar results to the 635 nm laser.

CONCLUSIONS

The application of the 635 nm and 405 nm irradiation caused a statistically significant increase in the proliferation of gingival fibroblasts.

The Effects of Photobiomodulation on Leukocyte and Platelet-Rich Fibrin as Barrier Membrane on Bone Regeneration: An Experimental Animal Study

Objective: To compare the effects of leukocyte and platelet-rich fibrin (L-PRF) and photobiomodulation therapy (PBMT)-applied L-PRF (PBMT/L-PRF) as barrier membranes on new bone formation (BV/TV) for the treatment of critical-sized bone defects. Materials and methods: The right iliac crests of five sheep were used in this experimental animal study. Eight critical-sized defects were surgically created in each sheep and a total of 40 defects were obtained. A deproteinized bovine bone graft was placed in all defects, and the defects were divided into four groups to be covered with L-PRF membrane, PBMT/L-PRF membrane, collagen membrane, or left uncovered as controls. Animals were sacrificed at 1 month. The sections obtained were histomorphometrically analyzed. Results: The results showed that the collagen group presented significantly higher values for main bone healing parameters (BV/TV, bone volume, and bone surface; p < 0.05). The PBMT/L-PRF group presented higher values than the L-PRF group and controls for these parameters though not statistically significant (p > 0.05). Conclusions: The findings show that PBMT may provide additional regenerative properties to L-PRF when used as barrier membranes. However, these results did not reach the collagen membranes, which warrants further studies for adapting the laser parameters to increase regenerative capacity of L-PRF.

Experimental Study on Blue Light Interaction with Human Keloid-Derived Fibroblasts

Keloids are an exuberant response to wound healing, characterized by an exaggerated synthesis of collagen, probably due to the increase of fibroblasts activity and to the reduction of their apoptosis rate: currently no standard treatments or pharmacological therapies are able to prevent keloid recurrence. To reach this goal, in recent years some physical treatments have been proposed, and among them the PhotoBioModulation therapy (PBM). This work analyses the effects of a blue LED light irradiation (410-430 nm, 0.69 W/cm² power density) on human fibroblasts, isolated from both keloids and perilesional tissues. Different light doses (3.43-6.87-13.7-20.6-30.9 and 41.2 J/cm²) were tested. Biochemical assays and specific staining were used to assess cell metabolism, proliferation and viability. Micro-Raman spectroscopy was used to explore direct effects of the blue LED light on the Cytochrome C (Cyt C) oxidase. We also investigated the effects of the irradiation on ionic membrane currents by patch-clamp recordings. Our results showed that the blue LED light can modulate cell metabolism and proliferation, with a dose-dependent behavior and that these effects persist at least till 48 h after treatment. Furthermore, we demonstrated that the highest fluence value can reduce cell viability 24 h after irradiation in keloid-derived fibroblasts, while the same effect is observed 48 h after treatment in perilesional fibroblasts. Electrophysiological recordings showed that the medium dose (20.6 J/cm²) of blue LED light induces an enhancement of voltage-dependent outward currents elicited by a depolarizing ramp protocol. Overall, these data demonstrate the potentials that PBM shows as an innovative and minimally-invasive approach in the management of hypertrophic scars and keloids, in association with current treatments.

In Vitro Cytological Responses against Laser Photobiomodulation for Periodontal Regeneration

Periodontal disease is a chronic inflammatory disease caused by periodontal bacteria. Recently, periodontal phototherapy, treatment using various types of lasers, has attracted attention. Photobiomodulation, the biological effect of low-power laser irradiation, has been widely studied. Although many types of lasers are applied in periodontal phototherapy, molecular biological effects of laser irradiation on cells in periodontal tissues are unclear. Here, we have summarized the molecular biological effects of diode, Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO₂ lasers irradiation on cells in periodontal tissues. Photobiomodulation by laser irradiation enhanced cell proliferation and calcification in osteoblasts with altering gene expression. Positive effects were observed in fibroblasts on the proliferation, migration, and secretion of chemokines/cytokines. Laser irradiation suppressed gene expression related to inflammation in osteoblasts, fibroblasts, human periodontal ligament cells (hPDLCs), and endothelial cells. Furthermore, recent studies have revealed that laser irradiation affects cell differentiation in hPDLCs and stem cells. Additionally, some studies have also investigated the effects of laser irradiation on endothelial cells, cementoblasts, epithelial cells, osteoclasts, and osteocytes. The appropriate irradiation power was different for each laser apparatus and targeted cells. Thus, through this review, we tried to shed light on basic research that would ultimately lead to clinical application of periodontal phototherapy in the future.

Immunomodulatory effects of Nd:YAG (1064 nm) and diode laser (810 nm) wavelengths to LPS-challenged human gingival fibroblasts

OBJECTIVE

Human gingival fibroblasts (hGFs) are involved in inflammatory responses to bacteria by recognizing pathogen-associated molecular patterns. In search of host modulation strategies to increase LPS tolerance, Low level laser therapy (LLLT) has been suggested as an alternative treatment that reduces periodontal tissue inflammation. In this study, we investigate whether 810 nm (diode) and 1064 nm (Nd:YAG) laser wavelengths, modulate pro-inflammatory responses to LPS challenges in hGFs.

DESIGN

Primary hGFs were challenged with Porphyromonas gingivalis LPS and irradiated with either Diode (810 nm) or with Nd:YAG (1064 nm) lasers. Cell cultures were examined for cell proliferation by MTT assay and IL-6 and IL-8 expression by qPCR at 24, 48 and 72 h. IL-6 and IL-8 protein levels were detected via ELISA.

RESULTS

Naïve hGF populations irradiated with both Diode 810 nm and Nd:YAG 1064 nm lasers demonstrated cellular proliferation (p < 0.05), but LLLT did not affect cellular viability in LPS-challenged cells. IL-6 and IL-8 gene expression levels revealed significant anti-inflammatory effects of irradiation with both examined wavelengths on hGFs challenged with P. gingivalis LPS. Protein levels of these cytokines were increased by LPS challenge. Treatment with LLLT inhibited this increase for both wavelengths evaluated in the study at a statistically significant level particularly for the first 48 h.

CONCLUSIONS

The present study demonstrates a modulatory effect of LLLT using both 810 nm diode and Nd:YAG 1064 nm lasers in gingival fibroblasts by decreasing the production of IL-6, IL-8 in response to LPS.

A Clinical Trial of Photobiomodulation Effect on Orthodontic Microscrews Stability Using a 635 nm Red Laser Light

Background: One of the procedures enhancing implants stability can be photobiomodulation. Objective: To assess the effect of a 635 nm wavelength on orthodontic microscrews stability, survival rate, and an individual patient's pain score. Materials and methods: The study was done with 15 subjects, 30 orthodontic microscrews with a length of 10 mm and diameter 1.4 mm. Implants inserted on the right and left side of the maxilla. The implants in the test group (G1) were irradiated with the laser at palatal and buccal part of peri-implant area (two points). The diode laser (SmartM PRO; Lasotronix, Warsaw, Poland) was used with the following settings: power: 100 mW, spot size: 0.5 cm², mean power density (irradiance): 200 mW/cm², in continuous wave (CW) mode, energy per point: 4 J, radiant exposure: 8 J/cm², time per point: 40 sec, the total energy dose (radiant energy) per session: 8 J in contact mode, handpiece diameter: 8 mm. Laser sessions: day of surgery and 3, 6, 9, 12, 15, 30 days later. Cumulative radiant energy was 59 J. Periotest appliance was used to assess the microscrews stability at day of surgery and 3, 6, 9, 12, 15, 30, 60 days later. Each patient received a survey for individual pain assessment (NRS-11) promptly after the implantation. Results: The analysis after 60 days revealed significantly higher secondary stability for the laser-irradiated microscrews group in comparison with control implants (G2 group) (p = 0.0037). We observed significantly higher stability in the experimental group compared with the control after 30 days (p = 0.0218). Moreover, we noted significantly higher microimplants stability for the control group in comparison with the test group, 9 days after implantation (p = 0.0374). Laser application had no effect on pain reduction noted in the first day in comparison with the control sites (p = 0.6690). No microscrews were lost in the study. Conclusions: Application of a 635 nm laser on peri-implant soft tissue increased the microscrews stability after 30 and 60 days.

A Comparative Clinical Study between Concentrated Growth Factor and Low-Level Laser Therapy in the Management of Dry Socket

OBJECTIVE

 A dry socket is a well-recognized complication of wound healing following tooth extraction. Its etiology is poorly understood and commonly occur among healthy patients. As such, management strategies for dry socket has always been empirical rather than scientific with varying outcome. The aim of this study is to investigate the efficacy of concentrated growth factor (CGF) and low-level laser therapy (LLLT) and compared them to the conventional treatment in the management of dry socket.

MATERIALS AND METHODS

 Sixty patients with one dry socket each, at University Dental Hospital Sharjah, were divided into three treatment groups based on their choice. In group I (n = 30), conventional treatment comprising of gentle socket curettage and saline irrigation was done. Group II (n = 15) dry sockets were treated with CGF and group III (n = 15) sockets were lased with LLLT. All dry socket patients were seen at day 0 for treatment and subsequently followed-up at 4, 7, 14, and 21 days. Pain score, perisocket inflammation, perisocket tenderness, and amount of granulation tissue formation were noted.

STATISTICAL ANALYSIS

 Data were analyzed as mean values for each treatment group. Comparisons were made for statistical analysis within the group and among the three groups to rank the efficacy of treatment using one-way analysis of variance (ANOVA). Statistically significant difference is kept at p < 0.05.

RESULTS

 Conventional treatment group I took more than 7 days to match the healing phase of group II CGF treated socket and group III LLLT irradiated socket (p = 0.001). When healing rate between CGF and LLLT are compared, LLLT group III showed a delay of 4 days compared with CGF in granulation tissue formation and pain control.

CONCLUSION

 CGF treated socket was superior to LLLT in its ability to generate 75% granulation tissue and eliminate pain symptom by day 7 (p = 0.001).

Regulation of osteogenesis via miR-101-3p in mesenchymal stem cells by human gingival fibroblasts

INTRODUCTION

Mesenchymal stem cells (MSCs) can differentiate into various types of cells and can thus be used for periodontal regenerative therapy. However, the mechanism of differentiation is still unclear. Transplanted MSCs are, via their transcription factors or microRNAs (miRNAs), affected by periodontal cells with direct contact or secretion of humoral factors. Therefore, transplanted MSCs are regulated by humoral factors from human gingival fibroblasts (HGF). Moreover, insulin-like growth factor (IGF)-1 is secreted from HGF and regulates periodontal regeneration. To clarify the regulatory mechanism for MSC differentiation by humoral factors from HGF, we identified key genes, specifically miRNAs, involved in this process, and determined their function in MSC differentiation.

MATERIALS AND METHODS

Mesenchymal stem cells were indirectly co-cultured with HGF in osteogenic or growth conditions and then evaluated for osteogenesis, undifferentiated MSC markers, and characteristic miRNAs. MSCs had their miRNA expression levels adjusted or were challenged with IGF-1 during osteogenesis, or both of which were performed, and then, MSCs were evaluated for osteogenesis or undifferentiated MSC markers.

RESULTS

Mesenchymal stem cells co-cultured with HGF showed suppression of osteogenesis and characteristic expression of ETV1, an undifferentiated MSC marker, as well as miR-101-3p. Over-expression of miR-101-3p regulated osteogenesis and ETV1 expression as well as indirect co-culture with HGF. IGF-1 induced miR-101-3p and ETV1 expression. However, IGF-1 did not suppress osteogenesis.

CONCLUSIONS

Humoral factors from HGF suppressed osteogenesis in MSCs. The effect was regulated by miRNAs and undifferentiated MSC markers. miR-101-3p and ETV1 were the key factors and were regulated by IGF-1.

Management of dry socket with low-level laser therapy

OBJECTIVE

The aim of this study is to investigate the efficacy of delivering low-level laser therapy (LLLT) in the management of dry socket at University Dental Hospital Sharjah.

MATERIALS AND METHOD

Forty-five patients with dry socket were divided into two treatment groups. Group I dry socket patients (n = 30) received conventional treatment while group II patients (n = 15) were irradiated with LLLT at a setting of 200-mW, 6-J, continuous-wave mode using an R02 tipless handpiece (Fotona Er:YAG, Europe), on the buccal, lingual, and middle surfaces of the socket for 30 s from a delivery distance of 1 cm. Pain score and quantification of granulation tissue in the socket were recorded at 0, 4, and 7 days post-dry socket treatment.

RESULTS

Results showed that the LLLT-irradiated group II sockets showed a much lower VAS pain score of 1-2 as early as day 4, and a richer amount of granulation tissue compared to the conventional treated group I socket. The amount and rate of granulation tissue formation in the dry socket are inversely proportional to the pain score showing significant clinical effectiveness of LLLT on promoting the healing of the dry socket, with improvement in symptoms (P = .001). Conventionally treated dry sockets take at least 7 days to match the effective healing of an LLLT-irradiated dry socket.

CONCLUSION

LLLT irradiation influences biomodulation of dry socket healing by dampening inflammation, promoting vascularization, stimulating granulation, and controlling pain symptoms.

CLINICAL RELEVANCE

LLLT may be an additional effective tool for managing dry sockets in general dental practice.

Phenytoin sodium-ameliorated gingival fibroblast aging is associated with autophagy

BACKGROUND AND OBJECTIVE

Human gingival fibrolasts aging is an important cause of periodontal disease. Phenytoin sodium (phenytoin) has a side effect of gingival hyperplasia and an effect on the autophagy progress. This study investigated whether the effect of phenytoin on aging gingival fibroblast is related to the autophagy pathway.

MATERIAL AND METHODS

The aging model of gingival fibroblast cell line HGF-1 was induced by hydrogen peroxide (H₂ O₂ ), and the treatment of phenytoin and 3-methyladenine (3-MA) was performed simultaneously. Cell viability, cell cycle, and intracellular calcium ion were measured by flow cytometry. Changes in expression of basic fibroblast growth factor (bFGF), P16^INK4A , P21^cip1 , and bFGF, P16^INK4A , P21^cip1 , LC3II, p62, and Beclin were tested by using reverse transcription polymerase chain reaction, western blot, and immunofluorescence staining.

RESULTS

The results showed that aging HGF-1 proliferation was inhibited by H₂ O₂ , gene, protein expression of bFGF, P16^INK4A , and P21^cip1 were decreased, autophagy-related proteins LC3II, p62, and Becline were decreased, and the proportion of G0/G1 phase and intracellular calcium ion of cell cycle was increased. Phenytoin treatment could recovery above changes, but the effect of phenytoin could be blocked by 3-MA.

CONCLUSION

We propose that phenytoin alleviates the aging of gingival fibroblasts induced by H₂ O₂ . This condition is related to the enhancement of autophagy pathway.

Combination of laser and human adipose-derived stem cells in repair of rabbit anal sphincter injury: a new therapeutic approach

Background

Anal sphincter injury leads to fecal incontinence. Based on the regenerative capability of laser and human adipose-derived stem cells (hADSCs), this study was designed to assess the effects of co-application of these therapies on anal sphincter recovery after injury.

Design

Male rabbits were assigned to equal groups (n = 7) including control, sphincterotomy, sphincterotomy treated with laser (660 nm, 90 s, immediately after sphincterotomy, daily, 14 days), hADSCs (2 × 10⁶ hADSCs injected into injured area of the sphincter immediately after sphincterotomy), and laser + hADSCs. Ninety days after sphincterotomy, manometry and electromyography were performed, sphincter collagen content was evaluated, and Ki67, myosin heavy chain (MHC), skeletal muscle alpha-actin (ACTA1), vascular endothelial growth factor A (VEGFA), and vimentin mRNA gene expression were assessed.

Results

The laser + hADSCs group had a higher resting pressure compared with the sphincterotomy (p < 0.0001), laser (p < 0.0001), and hADSCs (p = 0.04) groups. Maximum squeeze pressure was improved in all treated animals compared with the sphincterotomized animals (p < 0.0001), without a significant difference between treatments (p > 0.05). In the laser + hADSCs group, motor unit numbers were higher than those in the laser group (p < 0.0001) but did not differ from the hADSCs group (p = 0.075). Sphincterotomy increased collagen content, but the muscle content (p = 0.36) and collagen content (p = 0.37) were not significantly different between the laser + hADSCs and control groups. Laser + hADSCs increased ACTA1 (p = 0.001) and MHC (p < 0.0001) gene expression compared with laser or hADSCs alone and was associated with increased VEGFA (p = 0.009) and Ki67 mRNA expression (p = 0.01) and decreased vimentin mRNA expression (p < 0.0001) compared with laser.

Conclusion

The combination of laser and hADSCs appears more effective than either treatment alone for promoting myogenesis, angiogenesis, and functional recovery after anal sphincterotomy.

Photobiomodulation therapy (PBMT) in bone repair: A systematic review

BACKGROUND

Photobiomodulation therapy (PBMT) using low-level laser influences the release of several growth factors involved in the formation of epithelial cells, fibroblasts, collagen and vascular proliferation, besides accelerating the synthesis of bone matrix due to the increased vascularization and lower inflammatory response, with significant increase of osteocytes in the irradiated bone. Considering its properties, beneficial effects and clinical relevance, the aim of this review was to analyze the scientific literature regarding the use of PBMT in the process of bone defect repair.

METHODS

Electronic search was carried out in PubMed/MEDLINE^Ⓡ and Web of Science databases with combination of the descriptors low-level laser therapy AND bone repair, considering the period of publication until the year 2018.

RESULTS

The literature search identified 254 references in PubMed/MEDLINE and 204 in Web of Science, of which 33 and 4 were selected, respectively, in accordance with the eligibility requirements. The analysis of researches showed articles using PBMT in several places of experimentation in the subjects, different types of associated biomaterials, stimulatory effects on cell proliferation, besides variations in the parameters of use of laser therapy, mainly in relation to the wavelength and density of energy. Only four articles reported that the laser did not improve the osteogenic properties of a biomaterial.

CONCLUSIONS

Many studies have shown that PBMT has positive photobiostimulatory effects on bone regeneration, accelerating its process regardless of parameters and the use of biomaterials. However, standardization of its use is still imperfect and should be better studied to allow correct application concerning the utilization protocols.

Abnormal expression of Pappa2 gene may indirectly affect mouse hip development through the IGF signaling pathway

INTRODUCTION

Developmental dysplasia of the hip (DDH) is a major cause of disability in children, and the genetic mechanism of this disease remains unclear. In our previous study, we found that pregnancy-associated plasma protein-A2 (PAPP-A2) was associated with DDH significantly.

OBJECTIVES

The aim of this study was to investigate the insulin-like growth factor (IGF) expression and collagen synthesis as well as cartilage proliferation-related proteins in the case of abnormal expression of Pappa2 in mice to research the relationship between PAPP-A2 and the pathological changes of DDH.

METHODS

In vivo animal experiments, the mice were directly injected with 50 µl of Cas9/PAPP-A2 sgRNA lentiviruses around the hip to downregulate the Pappa2 gene expression and injected with control lentiviruses on the other side, then to observe the expression and localization of related proteins. And in an in vitro experiment, mice fibroblasts and primary chondrocytes were cultured with insulin-like growth factor binding protein-5 (IGFBP-5) protein, PAPP-A2 protein and Cas9/PAPP-A2 sgRNA lentiviruses to detect of related proteins and mRNA expression.

RESULTS

Cartilage proliferation-related proteins demonstrated a significant decrease in the PAPP-A2 knockdown hips acetabulum and femoral head cartilage, meanwhile the IGF expression was also downregulated in the soft tissue around the acetabulum compared with the control hips. Furthermore, the role PAPP-A2 played in chondrocytes and fibroblasts was the same as in the in vivo experiments, downregulation of PAPP-A2 expression or upregulation of IGFBP-5 expression can reduce collagen synthesis and cartilage proliferation.

CONCLUSIONS

PAPP-A2 may be involved in the development of the mouse hip joint by interfering the fibrous and cartilaginous metabolism via IGF pathway-associated proteins pathway.

Tumor safety and side effects of photobiomodulation therapy used for prevention and management of cancer treatment toxicities. A systematic review

Photobiomodulation therapy (PBMT), also known as low-level laser therapy (LLLT), has been increasingly used for the treatment of toxicities related to cancer treatment. One of the challenges for the universal acceptance of PBMT use in cancer patients is whether or not there is a potential for the light to stimulate the growth of residual malignant cells that evaded oncologic treatment, increasing the risk for tumor recurrences and development of a second primary tumor. Current science suggests promising effects of PBMT in the prevention and treatment of breast cancer-related lymphedema and oral mucositis, among other cancer treatment toxicities. Nevertheless, this seems to be the first systematic review to analyze the safety of the use of PBMT for the management of cancer-related toxicities. Scopus, MEDLINE/PubMed, and Embase were searched electronically. A total of 27 articles met the search criteria. Selected studies included the use of PBMT for prevention and treatment of oral mucositis, lymphedema, radiodermatitis, and peripheral neuropathy. Most studies showed that no side effects were observed with the use of PBMT. The results of this systematic review, based on current literature, suggest that the use of PBMT in the prevention and management of cancer treatment toxicities does not lead to the development of tumor safety issues.

Low-level laser therapy as a modifier of erythrocytes morphokinetic parameters in hyperadrenalinemia

Low-level laser therapy (LLLT) is widely used in clinical practice for treatment of various pathologies. It is assumed that LLLT impact on microcirculation is among the mechanisms underlying its therapeutic effect. The microcirculation disorder is observed in the pathogenesis of any inflammatory process and is significantly influenced by red blood cells (RBCs). On this point, studying the RBCs morphology under the influence of LLLT on alterated organism is of scientific interest and practical importance. The aim of the present study was to analyze the LLLT effect on morphokinetic parameters of RBCs in hyperadrenalinemia. The LLLT effect was analyzed on rats intraperitoneally injected with adrenaline hydrochloride solution (0.1 mg/kg). As the comparison groups, the effects of LLLT, adrenaline, or saline injection as well as the parameters of intact animals were studied. LLLT was applied on the occipital region of rats for 10 min. The light irradiation with pulse frequency 415 Hz at 890 nm wavelength and average power density in the plane of the output window at 193 μW/cm² was used. The dynamics of morphological characteristics of RBCs was studied by phase interference microscopy; the RBC electrophoretic mobility was tested by microelectrophoresis technique; photometric analyses of the RBCs amount, hemoglobin content, and osmotic fragility were performed. The adrenaline injection resulted in a significant increase in the amount of RBC pathological forms and a decrease in discocytes and normocytes by more than 50%. An increase in the optical density of RBC phase portraits, a decline in osmotic resistance, and electronegativity of RBC membranes and a reduction of their number in peripheral blood were also registered. The revealed effects persisted for 1 week after the adrenaline administration. LLLT did not significantly impact on the RBC parameters 1 h after adrenaline injection. However, a day later, LLLT reduced the severity of the adrenaline effect on RBSs, which was manifested in a decreased amount of the pathological forms of RBCs, restored RBC phase portraits, higher electrophoretic mobility and osmotic resistance, and RBSs amount in peripheral blood restored up to the level of intact animals. We suppose that the mechanism of LLLT action is realized both at cellular level through the laser radiation effect on RBC membranes, and at systemic level through the activation of stress-realizing systems of the organism with subsequent limitation of inflammatory response.

A Comparison of 940 nm Diode Laser and Cryosurgery With Liquid Nitrogen in the Treatment of Gingival Physiologic Hyperpigmentation Using Split Mouth Technique: 12 Months Follow Up

Introduction: Gingival hyperpigmentation is excessive deposition of melanin pigments in the epithelium of gingiva which affects facial esthetics. Various surgical methods for gingival depigmentation have been used to treat the darkened color of pigmented gingiva. This study compared the use of 940 nm diode laser and liquid nitrogen cryosurgery in the treatment of gingival physiologic hyperpigmentation in terms of gingival depigmentation, postoperative pain, healing duration, pigmentation recurrence, and patients' satisfaction. Methods: Fifteen systemically healthy patients (11 females and 4 males; 17-35 years of age) with bilateral gingival physiologic hyperpigmentation were enrolled in this split-mouth randomized study. Maxillary anterior labial gingiva of each patient was divided into left and right halves, and each half was randomly depigmented by either laser or cryosurgery. Patients were given questionnaires to evaluate the procedures and were followed up in 3, 7, 10, 17 and 21 days postoperatively for the assessment of gingival healing and 1, 3, 6 and 12 months after the treatments to detect any sign of pigmentation recurrence. Results: The severity of post-op pain measured by visual analogue scale (VAS) was mild to average and showed no significant difference between the 2 modalities (P>0.05). There was no considerable swelling or hemorrhage after the treatment procedures and the healing duration was significantly shorter in laser (P<0.05). The degree of pigmentation in all gingival sites treated by laser reached and remained at zero until the last follow up (1 year) and reached zero in 9 out of 15 cryosurgerytreated sites. All patients were completely satisfied with the laser, and 9 out of 15 were completely satisfied with cryosurgery. No pigmentation recurrence was observed during any follow-up periods. Conclusion: Removal of gingival physiologic hyperpigmentation by laser therapy and cryotherapy was effective and safe. The efficiency of the laser was better than cryotherapy.

A brief literature review and own clinical experience in prophylaxis of oral mucositis in children using low level laser therapy

OBJECTIVE

The article describes the experience of clinical application of low level laser therapy in pediatric oncology for the prevention and treatment of chemotherapy complications such as oral mucositis.

BACKGROUND

For this purpose, for the first time in the world non-invasive laser blood illumination is used on the sinocarotid zone (on the projection of the common carotid artery symmetrically) and popliteal fossa in order to stimulate the phagocytic activity of leukocytes.

METHODS

25 children with different oncological diseases were given non-invasive laser blood illumination treatment (904 nm, pulse mode, 100 ns, 50-150 Hz, 5-7 W, 4 cm², 1-2 minutes daily per each procedure) 1-3 days before the beginning of chemotherapy. For the objectification of the results of treatment, the phagocytic activity of leukocytes was evaluated.

RESULTS

None of the children who underwent low level laser therapy course had any complications and no cases of oral mucositis developed.

CONCLUSIONS

Clinical experience has shown high efficacy and safety of low level laser therapy aimed at preventing the development of complications of chemotherapy, primarily oral mucositis, and stimulating the phagocytic activity of leukocytes.

Diode Laser as an Adjunct to Kirkland Flap Surgery-A Randomized Split-Mouth Clinical and Microbiological Study

Background: Mechanical methods of periodontal therapy alone may fail to eliminate the tissue-invasive pathogenic flora; therefore, considerable attention has been given to adjunctive antimicrobial measures. Objective: The aim of this study was to investigate and compare the clinical and microbiological effects of diode laser (DL) as an adjunct to Kirkland flap surgery versus Kirkland flap surgery alone for the treatment of generalized chronic periodontitis. Materials and methods: A total of 20 patients with generalized chronic periodontitis with probing pocket depth ≥5 mm after phase I therapy were included in this split-mouth study. Two contralateral quadrants of each patient were randomly assigned to either test or control group. Control group was treated with Kirkland flap surgery alone, whereas test group was treated with DL as an adjunct to Kirkland flap surgery. Periodontal parameters were recorded, and subgingival plaque samples were collected from both the control and test groups at baseline and third and sixth month. The plaque samples were then analyzed for red complex organisms using quantitative real-time polymerase chain reaction. Results: Compared with baseline, both treatments showed an improvement in periodontal parameters at the third and sixth month. However, test group produced a significant improvement in plaque index (1.039 ± 0.069 vs. 1.392 ± 0.17, p < 0.001), bleeding on probing (16.512 ± 5.982 vs. 37.051 ± 7.459, p < 0.001), probing pocket depth (1.727 ± 0.39 vs. 3.016 ± 0.47, p < 0.001), and clinical attachment level (2.054 ± 0.524 vs. 3.354 ± 0.728, p < 0.001) at third and sixth month compared with the control group. Moreover, in the test group, levels of red complex bacteria were significantly reduced at third and sixth month compared with the control group. Conclusions: DL as an adjunct to Kirkland flap surgery has resulted in a greater reduction in clinical and microbiological parameters compared with Kirkland flap surgery alone, thereby offering additional benefit in treating generalized chronic periodontitis patients.

Expression of PAPP-A2 and IGF Pathway-Related Proteins in the Hip Joint of Normal Rat and Those with Developmental Dysplasia of the Hip

Developmental dysplasia of the hip (DDH) is one of the major causes of child disability and early osteoarthritis. Genetic factors play an important role, but which still remain unclear. Pregnancy-associated plasma protein-A2 (PAPP-A2), a special hydrolase of insulin-like growth factor binding protein-5 (IGFBP-5), has been confirmed to be associated with DDH by previous studies. The aim of this study was firstly, to investigate the expression of PAPP-A2 and insulin-like growth factor (IGF) pathway-related proteins in normal rat's hip joints; secondly, to compare the variations of those proteins between DDH model rats and normal ones. The DDH model was established by swaddling the rat's hind legs in hip adduction and extension position. The hip joints were collected for expression study of fetal rats, normal newborn rats, and DDH model rats. Positive expression of PAPP-A2 and IGF pathway-related proteins was observed in all the hip joints of growing-stage rats. Ultimately, IGF1 was downregulated; insulin-like growth factor 1 receptor (IGF1R) showed an opposite trend in DDH rats when compared with normal group. The PAPP-A2 and IGF pathway-associated proteins may also be involved in the development of the rat's hip joint, which bring the foundation for further revealing the pathogenic mechanism of DDH.