Clinical study on the efficacy of LED phototherapy for pain control in an orthodontic procedure

Biphasic dose-response and effects of near-infrared photobiomodulation on erythrocytes susceptibility to oxidative stress in vitro

The effect of simultaneous application of tert-butyl hydroperoxide (tBHP) and polychromatic near-infrared (NIR) radiation on bovine blood was examined to determine whether NIR light decreases the susceptibility of red blood cells (RBCs) to oxidative stress. The study assessed various exposure methods, wavelength ranges, and optical filtering types. Continuous NIR exposure revealed a biphasic response in cell-free hemoglobin changes, with antioxidative effects observed at low fluences and detrimental effects at higher fluences. Optimal exposure duration was identified between 60 s and 15 min. Protective effects were also tested across wavelengths in the range of 750-1100 nm, with all of them reducing hemolysis, notably at 750 nm, 875 nm, and 900 nm. Comparing broadband NIR and far-red light (750 nm) showed no significant difference in hemolysis reduction. Pulse-dosed NIR irradiation allowed safe increases in radiation dose, effectively limiting hemolysis at higher doses where continuous exposure was harmful. These findings highlight NIR photobiomodulation's potential in protecting RBCs from oxidative stress and will be helpful in the effective design of novel medical therapeutic devices.

Impact of orthodontic treatment on OHRQoL of adolescents: a longitudinal study

OBJECTIVE

The aim of this study was to evaluate the extent to which orthodontic treatment need is perceived by the patients and by the orthodontist, as well as the possible impacts on the OHRQoL (Oral Health-Related Quality of Life) over the course of conventional orthodontic treatment in adolescent patients.

METHODS

The sample consisted of 55 adolescents. The perception of patients and orthodontists relative to the malocclusion was evaluated by the IOTN (Index of Orthodontic Treatment Need). The OHRQoL was evaluated by the Child-OIDP (Child-Oral Impacts on Daily Performances) questionnaire before the conventional orthodontic appliance was bonded (T0); and at the following time intervals: after one week (T1), one month (T2), three months (T3), six months (T4), and after the end of orthodontic treatment (T5).

RESULTS

Adolescents who had large orthodontic treatment needs had a poor OHRQoL, according to their self-perception (p=0.003) and according to the orthodontist's perception (p<0.001), when compared with patients with small and moderate needs. There was statistically significant difference in the OHRQoL between the time intervals T0 and T1 (p=0.021), T2 and T3 (p<0.001), T3 and T4 (p=0.033), and T0 and T5 (p<0.002). At the end of treatment, all evaluated participants reported an improvement in OHRQoL.

CONCLUSIONS

It was concluded that adolescents and orthodontists agreed with regard to the perception of orthodontic treatment need. In the first week and in the first month of orthodontic treatment, there was a negative impact on the OHRQoL. After three months, an improvement of OHRQoL was detected, which has progressed over time.

The effectiveness of interventions in reducing pain related to orthodontic separation: a systematic review and meta-analysis

BACKGROUND

Pain is an unpleasant experience and annoying sensation. To control this pain during orthodontic separation, different pharmacological and non-pharmacological methods have been used.

OBJECTIVE

This systematic review and meta-analysis aimed to critically assess the evidence of the effectiveness of pharmacological and non-pharmacological methods in reducing pain induced by orthodontic separation.

SEARCH STRATEGY

An electronic search was conducted using the following databases: PubMed® (Medline), Scopus®, EMBASE®, Web of ScienceTM, Google ScholarTM, ProQuest, and Cochrane Central Register of controlled trials (CENTRAL) searching for the studies published between January 2012 and April 2023.

SELECTION CRITERIA

Only randomized controlled trials (RCTs) were included, each experimental group included patients who received elastomeric separators and one kind of pharmacological or non-pharmacological interventions for pain reduction during the separation stage.

DATA COLLECTION AND ANALYSIS

Cochrane's risk of bias tool (RoB2 tool) was applied. The Grading of Recommendations Assessment, Development, and Evaluation [GRADE] approach was used to evaluate the strength of the evidence.

RESULTS

Thirty-one studies (RCTs) were included in this systematic review. Nineteen of them were appropriate for quantitative synthesis and used VAS for pain assessment. Meta-analysis showed that low-level laser therapy (LLLT) was an effective approach for pain relief after separators placement with standard mean difference of 13.79 mm (95% confidence interval (CI): -15.64, -11.94) at 6 h and 23.34 mm at 24 h (95% CI: -25.91, -20.77). LLLT was also effective when applied in split-mouth and the standard mean difference was 8.9 mm at 6 h (95% CI: -12.86, -3.33) and 17.15 mm at 24 h (95% CI: -30.12, -4.17). Ibuprofen had a pain control effect at 6 h and at 24 h compared with the placebo group. The standard mean difference was 14.37 mm (95% CI: -20.54, -8.19) and 20.46 mm (95% CI: -27.79, -13.13), respectively. There was no difference in pain control between ibuprofen and acetaminophen. Naproxen had lower visual analog scale scores in pain perception at 6 h and the standard mean difference was 7.03 mm (95% CI: -12.67, -1.40).

CONCLUSIONS

The application of LLLT decreased the pain induced by the separation during the first day of teeth separation; the pain reduction showed an increase from 6 h to the end of the 24 h. However, the evidence is weak to moderate. The analgesics reduced the pain compared to placebo; this pain reduction had shown an increase from 6 h to the end of the 24 h. The strength of the evidence is moderate. Naproxen gel effectively reduced the pain compared to placebo; the evidence in this regard is moderate. Naproxen gel effectively reduced the pain compared to placebo, but it was less effective than the oral intake of non-steroidal anti-inflammatory drugs. However, the evidence in this regard is moderate.

REGISTRATION

This systematic review was registered with PROSPERO (CRD42022335553) during the first stages of its conduction.

Effect of nanomicelle curcumin-based photodynamic therapy on the dynamics of white spot lesions and virulence of Streptococcus mutans in patients undergoing fixed orthodontic treatment: A randomized double-blind clinical trial

BACKGROUND/PURPOSE

The formation of white spot lesions (WSLs) around fixed orthodontic appliances is a major complication during treatment. The current double-blind, randomized clinical trial (RCT) study aims to investigate the varying effects of nanomicelle curcumin-based photodynamic therapy (NMCur-aPDT) on microbial count and virulence of Streptococcus mutans as well as the number and dynamics of WSLs.

MATERIALS AND METHODS

Double-blind prospective RCT, comprised of 48 patients with fixed orthodontic appliances, were recruited for the current study. The patients were divided into four groups according to the type of the treatment (NMCur, LED, NMCur-aPDT or VITIS® anti-caries mouthwash), using block randomization. Antimicrobial and anti-virulence activities of the treatments against isolated S. mutans were assessed via colony counting and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. The visual inspection using the International Caries Detection and Assessment System (ICDAS II) score and laser fluorescence (LF) detection using a DIAGNOdent device were used for the detection and assessment of the dynamics of WSLs, respectively, on the labial surface in four areas (i.e., gingival, incisal, mesial, and distal) of the upper and lower anterior teeth at 30-, 60-, 90-, and 120-days follow-up after bonding of the lower and upper arches.

RESULTS

The antimicrobial properties of NMCur, VITIS®, and NMCur-aPDT were time-dependent so the highest reduction in S. mutans population was observed following NMCur-aPDT (99.98%) on day 120 of the study. The gtfB gene expression levels in S. mutans isolates from the NMCur-aPDT group on days 60, 90, and 120 decreased by 2.07-, 2.32-, and 3.01-fold more than in S. mutans isolates from the VITIS® group, respectively (all P < 0.05), while NMCur and LED treatments could not significantly reduce gtfB gene expression up to 120 days of follow-up (P > 0.05). In patients who were treated with LED, an increase in the mean number of WSLs per patient (mean increase, 1.8; P < 0.05) was found, while in NMCur-aPDT and VITIS® groups, not only no increases were observed, but the mean number of WSLs per patient decreased (mean reductions, 0.5 and 0.9, respectively; not significant). LED treatment caused significant increases (P < 0.05) in the mean LF values at 90-and 120-days of follow-up in comparison with the baseline (mean increases, 5.1 and 6.5, respectively) while, in NMCur-aPDT, VITIS®, and NMCur groups 11.8-, 7.1-, and 4.4-reductions in the mean LF values were observed, respectively (all, P < 0.05).

CONCLUSIONS

The antimicrobial and anti-virulence activities of NMCur-aPDT against S. mutans were higher than the other treatment groups. In patients who were treated with NMCur-aPDT, the mean number and LF values of WSLs per patient were significantly lower than the other groups in 90-and 120-days of follow-up.

Comparative analysis of Laser and LED phototherapies pain control after insertion of elastomeric separators in orthodontics patients: Clinical trial

The aim of this study was to evaluate the effectiveness of pain modulation following Laser or LED phototherapies during the process of tooth separation. This was a longitudinal randomized controlled clinical trial in four observational times carried out in 60 patients (15 males, 45 females, average 24.1 years old) who were randomly divided into three groups: G1 (LED, AsGaAl, λ850 ± 10 nm, 150 mW, 17 J/cm², 57 s per session), G2 (Laser, AsGaAl, λ780 nm, 70 mW, 20.0 J/cm², 240 s per session) and G3 (Non-irradiated Control). All patients were submitted to tooth separation using elastomeric separators. The pain level was measured by using a visual analogue scale (VAS) immediately after insertion (T1) of the elastic, at 48 (T2), 96 (T3) hours and 6 days (T4). It was observed an increase of the pain on the Control group from T1 to T2, with statistical significance. Pain levels in the LED and Laser groups were always significantly lower (<0.001), except for T1. According with the results of the present study it may be concluded that, either LED or Laser phototherapies, were effective in reducing the pain level after dental separation process when compared to the control group.

Pain Reduction during Rapid Palatal Expansion Due to LED Photobiomodulation Irradiation: A Randomized Clinical Trial

Objective: The purpose of this research is to assess the analgesic efficiency of Photobiomodulation (PBM) in pain reduction in young patients during rapid maxillary expansion therapy. Materials and Methods: Thirty patients were included and allocated to an experimental group [Rapid Palatal Expansion (RPE) and PBM] and a control group (RPE only) at random. Inclusion criteria were skeletal age from CVS1 to CVS3, examined on the cephalometric lateral teleradiography, with cervical vertebra staging and completed eruption of upper first molar. Exclusion criteria were previous orthodontic treatment, bone disease, disability, or skeletal age from CVS4. Patients referred the pain they felt using a Numerical scale rate (NRS), ranging from 0 to 10, with specific intervals of time: 6 h, 12 h, 24 h, and from days 2 to 7. The Wilcoxon-Mann-Whitney test was used to evaluate differences in NRS reported values between the two groups. Results: The final sample included 30 patients, 14 males and 16 females, with a mean age of 7.8 ± 1.2 years. The pain that was felt at each time interval and the maximum score of pain were significantly lower in the experimental group (p < 0.05) and decreased faster in the experimental group, with a score test near to 0 after 2/3 days. Conclusions: PBM is efficient in reducing the intensity and the time of pain felt by young patients that undergo rapid maxillary expansion.

Blue-light treatment reduces spontaneous and evoked pain in a human experimental pain model

Supplemental Digital Content is Available in the Text.

Blue light reduces pain and shows antihyperalgesic effects in a human experimental pain model. Therefore, blue light may be a novel therapeutic approach for pain in multiple conditions.

Introduction:

Chronic pain is a frequent severe disease and often associated with anxiety, depression, insomnia, disability, and reduced quality of life. This maladaptive condition is further characterized by sensory loss, hyperalgesia, and allodynia. Blue light has been hypothesized to modulate sensory neurons and thereby influence nociception.

Objectives:

Here, we compared the effects of blue light vs red light and thermal control on pain sensation in a human experimental pain model.

Methods:

Pain, hyperalgesia, and allodynia were induced in 30 healthy volunteers through high-density transcutaneous electrical stimulation. Subsequently, blue light, red light, or thermal control treatment was applied in a cross-over design. The nonvisual effects of the respective light treatments were examined using a well-established quantitative sensory testing protocol. Somatosensory parameters as well as pain intensity and quality were scored.

Results:

Blue light substantially reduced spontaneous pain as assessed by numeric rating scale pain scoring. Similarly, pain quality was significantly altered as assessed by the German counterpart of the McGill Pain Questionnaire. Furthermore, blue light showed antihyperalgesic, antiallodynic, and antihypesthesic effects in contrast to red light or thermal control treatment.

Conclusion:

Blue-light phototherapy ameliorates pain intensity and quality in a human experimental pain model and reveals antihyperalgesic, antiallodynic, and antihypesthesic effects. Therefore, blue-light phototherapy may be a novel approach to treat pain in multiple conditions.

The Effectiveness of Low-Level Laser Therapy in Pain Induced by Orthodontic Separator Placement: A Systematic Review

Introduction: This systematic review was conducted to evaluate the effectiveness of low-level laser therapy (LLLT) in orthodontic separator pain. Methods: This article was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Electronically and manually 3 databases, namely PubMed, Scopus and Google Scholar, were searched by the keywords that were selected based on population, intervention, comparison and outcome (PICO) on October 10, 2020. Studies were appraised by Cochrane version 5.2.0 with 7 domains and were checked by these inclusion criteria: 1. Randomized clinical trial (RCT) that examined the efficacy of LLLT in separator pain, 2. Split-mouth design, 3. LLLT application in the first hours after separator placement, 4. LLLT application to both sides of the teeth, 5. Patients receiving elastomeric separators between the premolars and molars, 6. Lasers with a wavelength of 800-899 nm, 7. Studies conducted from 2010 to 2020, and 8. Participants who went through orthodontic treatment without limitation in gender, age and social-economic status. Results: 299 studies were screened. 34 full-text papers were read by 2 authors independently. In the end, 4 articles met the inclusion criteria. All 4 articles showed LLLT has a significant impact on pain reduction. Conclusion: The exact protocol for laser therapy is still not clear. Therefore, more studies with a meticulously designed method are needed.

Shear bond strength, adhesive remnant index, and anti-biofilm effects of a photoexcited modified orthodontic adhesive containing curcumin doped poly lactic-co-glycolic acid nanoparticles: An ex-vivo biofilm model of S. mutans on the enamel slab bonded brackets

BACKGROUND

Potential complications during fixed orthodontic procedures are white spot lesions (WSLs) and tooth decay. This study evaluated the anti-biofilm activity of an orthodontic adhesive (OA) incorporating curcumin (Cur) doped Poly lactic-co-glycolic acid nanoparticles (Cur-PLGA-NPs), which can have the highest concentration of Cur-PLGA-NPs and shear bond strength (SBS) value simultaneously, against cariogenic bacteria i.e., Streptococcus mutans.

MATERIALS AND METHODS

Following synthesis and confirmation of Cur-PLGA-NPs, SBS and adhesive remnant index (ARI) of the modified orthodontic adhesives (MOA) containing Cur-PLGA-NPs (3, 5, 7, and 10 % wt.) were measured using universal testing machine and stereomicroscope, respectively. After artificial aging (continuously rinsed up to 180 days), the residual anti-biofilm ability of MOA which can have the highest concentration of Cur-PLGA-NPs and SBS value simultaneously were determined by anti-biofilm assay following photoexcited enamel slab bonded brackets by MOA containing Cur-PLGA-NPs against S. mutans biofilms using crystal violet assay.

RESULTS

Adhesive with 7 % wt. Cur-PLGA-NPs revealed the highest concentration of Cur-PLGA-NPs and SBS value (16.19 ± 2.69 MPa, P < 0.05) simultaneously. No statistically significant difference in ARI scores was observed between the MOA and control (Transbond XT without the Cur-PLGA-NPs). On days 15, 30, 60, 90 and 120 there was a considerable decrease in optical density (OD) of preformed S. mutans biofilms on photoexcited enamel slab bonded brackets using MOA containing 7 % wt. Cur-PLGA-NPs, to 94.1 %, 79.6 %, 69.6 %, 69.4 %, and, 55.1 % respectively in comparison to the control group (all, P < 0.05). From days 150 onwards, microbial biofilm formation was progressively increased on enamel slab bonded brackets using MOA containing 7 % wt. Cur-PLGA-NPs compared to the control group (OA). Although chlorhexidine (2 %; as positive control) showed significant activity against pre-formed S. mutans biofilms on enamel slab bonded brackets using OA (99.1 % biofilm reduction; P = 0.001), its activity was slightly higher but not significant than photoexcited enamel slab bonded brackets using MOA containing 7 % wt. Cur-PLGA-NPs on the days 15 and 30 (both, P > 0.05).

CONCLUSIONS

The 7 % wt. Cur-PLGA-NPs can serve as an orthodontic adhesive antimicrobial additive as exposure to blue laser provides an acceptable antimicrobial effect against cariogenic bacteria for a considerable time.

Blue light therapy to treat candida vaginitis with comparisons of three wavelengths: an in vitro study

Anti-fungal blue light (ABL) therapies have been widely studied to treat various microbial infections in the literature. The blue light with wavelengths ranging from 400 to 470 nm has been reported to be effective to inhibit various kinds of bacteria and fungi. The existing studies usually report the viability rates of the pathogens under the irradiation of the blue light with different dosage parameters. However, to the best of our knowledge, there is still no work especially focusing on studying the effect of ABL therapies on treating candida vaginitis, where it is important to study the viability of both the Candida albicans (C. albicans) and the human vaginal epithelial cells. It is the purpose of this work to conduct ABL experiments on both of these two cells, analyze the effects, and determine the best ABL wavelength out of three candidates, i.e., 405-nm, 415-nm, and 450-nm wavelength. The viability rates of the C. albicans and the human vaginal epithelial cells irradiated by the three blue LED light sources were measured, whose irradiance (power density) were all set to 50 mW/cm². The dynamic viability models of the C. albicans and the epithelial cells were built based on the experimental data. Moreover, in this work, we also built a functional relationship between the viability of these two types of cells, by which we further compared the effects of the blue light irradiation on both the C. albicans and vaginal epithelial cells. The experimental data showed that when an approximately 80% inhibiting rate of the C. albicans was achieved, the survival rates of the epithelial cells were 0.6700, 0.7748, and 0.6027, respectively for the treatment by the 405-nm, 415-nm, and 450-nm wavelength light. On the other hand, by simulating the functional relationship between the viability of the two types of cells, the survival rates of the epithelial cells became 0.5783, 0.6898, and 0.1918 respectively using the 405-nm, 415-nm and 450-nm wavelength light, when the C. albicans was completely inhibited. Therefore, both the experimental data and the model simulation results have demonstrated that the 415-nm light has a more effective anti-fungal result with less damage to the epithelial cells than the 405-nm and 450-nm light.