A systematic review of the effective laser wavelength range in delivering photobiomodulation for pain relief in active orthodontic treatment

OBJECTIVE

This systematic review aimed to establish an effective wavelength range for PhotoBioModulation (PBM) to relieve pain in orthodontic treatments.

MATERIAL AND METHODS

The electronic literature search was carried out in the following databases: PubMed, ISI Web of Science, Scopus, and Cochrane. In the initial search, 255 papers were obtained. Deleting duplicates in the search left 180 items. One manually searched study was included for a total of 181 studies. According to PRISMA guidelines and a thorough analysis of their methodology, the final sample was composed of 13 RCTs. The final statistical analysis was performed in 11 studies. The statistical analysis sought to strengthen the collected data, determining the correlation coefficient (r) for the same time interval (24h) using a scale equivalent to the standard value (0-10cm). Aiming to reduce the effect of heterogeneity, the difference in cm between control group (GC) and experimental group (EG) averages was considered the outcome. This difference was correlated with the wavelength in nm, calculating the Pearson linear correlation coefficient, and calculating a logarithmic correlation.

RESULTS

The dispersion of the data obtained in the experimental groups at each given wavelength showed that the most significant number of studies were in the ranges of 780-830nm. The correlation between the wavelength and the difference between the control and experimental group averages, either linear (R2=0.0564, r=0.237) or logarithmic (R2=0.0688, r=0.262) was not significant (P>0.90). Therefore, pain reduction after 24h is not significantly dependent of wavelength.

CONCLUSION

The majority of RCTs related to pain relief in orthodontic treatment showed 780-830nm as the most effective photobiomodulation wavelength range for orthodontic pain relief. However, pain reduction after 24h is not significantly dependent of wavelength. The protocol was registered in PROSPERO (CRD42019119799).

Effects of photobiomodulation therapy on the local experimental envenoming by Bothrops leucurus snake

Bothrops leucurus is the major causative agent of snakebites in Brazil's Northeast. The systemic effects of its venom are effectively neutralized by antivenom therapy, preventing bitten patients' death. However, antivenom fails in neutralizing local effects that include intense pain, edema, bleeding, and myonecrosis. Such effects can lead to irreversible sequels, representing a clinically relevant issue for which there is no current effective treatment. Herein, the effects of photobiomodulation therapy (PBMT) were tested in the local actions induced by B. leucurus venom (BLV) in mice (n = 123 animals in 20 experimental groups). A continuous emission AlGaAs semiconductor diode laser was used in two wavelengths (660 or 780 nm). Mechanical nociceptive thresholds were assessed with the electronic von Frey apparatus. Local edema was determined by measuring the increase in paw thickness. Hemorrhage was quantified by digital measurement of the bleeding area. Myotoxicity was evaluated by serum creatine kinase (CK) activity and histopathological analysis. PBMT promoted anti-hypernociception in BLV-injected mice; irradiation with the 660 nm laser resulted in faster effect onset than the 780 nm laser. Both laser protocols reduced paw edema formation, whether irradiation was performed immediately or half an hour after venom injection. BLV-induced hemorrhage was not altered by PBMT. Laser irradiation delayed, but did not prevent myotoxicity caused by BLV, as shown by a late increase in CK activity and histopathological alterations. PBMT was effective in the control of some of the major local effects of BLV refractory to antivenom. It is a potential complementary therapy that could be used in bothropic envenoming, minimizing the morbidity of these snakebite accidents.

Clinical follow-up of corticotomy-accelerated Invisalign orthodontic treatment with Dental Monitoring

The demand for fast and invisible treatment options for adults has grown. Treatment protocols involving clear aligners in association with alveolar corticotomy have been developed in response to this demand. Alveolar corticotomy surgery can accelerate orthodontic tooth movement, but good clinical follow-up is crucial and can become cumbersome as the frequency of aligner changes accelerates. Clinical monitoring with patient-managed software can be of assistance in such cases. We present the ortho-surgical treatment of a healthy 21-year-old woman with Class III malocclusion who was treated with corticotomy-accelerated presurgical decompensation and clear aligners, followed by mandibular sagittal split osteotomy. Alveolar corticotomy surgery was performed and the aligners were changed every 4 days. Clinical follow-up of aligner-mediated tooth movement was managed with a patient-managed smartphone application, allowing early interception and correction of minute orthodontic movement errors. Such errors would have been difficult to detect considering the rapidity of aligner change when accelerated by alveolar corticotomy. Clinical follow-up with a patient-managed smartphone application could thus allow for better and easier management of corticotomy-accelerated clear aligner orthodontic treatment.

Phototherapy as a Rational Antioxidant Treatment Modality in COVID-19 Management; New Concept and Strategic Approach: Critical Review

The COVID-19 pandemic has taken the entire globe by storm. The pathogenesis of this virus has shown a cytokine storm release, which contributes to critical or severe multi-organ failure. Currently the ultimate treatment is palliative; however, many modalities have been introduced with effective or minimal outcomes. Meanwhile, enormous efforts are ongoing to produce safe vaccines and therapies. Phototherapy has a wide range of clinical applications against various maladies. This necessitates the exploration of the role of phototherapy, if any, for COVID-19. This critical review was conducted to understand COVID-19 disease and highlights the prevailing facts that link phototherapy utilisation as a potential treatment modality for SARS-CoV-2 viral infection. The results demonstrated phototherapy's efficacy in regulating cytokines and inflammatory mediators, increasing angiogenesis and enhancing healing in chronic pulmonary inflammatory diseases. In conclusion, this review answered the following research question. Which molecular and cellular mechanisms of action of phototherapy have demonstrated great potential in enhancing the immune response and reducing host-viral interaction in COVID-19 patients? Therefore, phototherapy is a promising treatment modality, which needs to be validated further for COVID-19 by robust and rigorous randomised, double blind, placebo-controlled, clinical trials to evaluate its impartial outcomes and safety.

Effect of Vitamins D and E on the Proliferation, Viability, and Differentiation of Human Dental Pulp Stem Cells: An In Vitro Study

Introduction

The aim of the present study was to determine the effects of vitamins D and E on the proliferation, morphology, and differentiation of human dental pulp stem cells (hDPSCs).

Methods

In this in vitro experimental study, hDPSCs were isolated, characterized, and treated with vitamins D and E, individually and in combination, utilizing different doses and treatment periods. Changes in morphology and cell proliferation were evaluated using light microscopy and the resazurin assay, respectively. Osteoblast differentiation was evaluated with alizarin red S staining and expression of RUNX2, Osterix, and Osteocalcin genes using real-time RT-PCR.

Results

Compared with untreated cells, the number of cells significantly reduced following treatment with vitamin D (49%), vitamin E (35%), and vitamins D + E (61%) after 144 h. Compared with cell cultures treated with individual vitamins, cells treated with vitamins D + E demonstrated decreased cell confluence, with more extensive and flatter cytoplasm that initiated the formation of a significantly large number of calcified nodules after 7 days of treatment. After 14 days, treatment with vitamins D, E, and D + E increased the transcription of RUNX2, Osterix, and Osteocalcin genes.

Conclusions

Vitamins D and E induced osteoblastic differentiation of hDPSCs, as evidenced by the decrease in cell proliferation, morphological changes, and the formation of calcified nodules, increasing the expression of differentiation genes. Concurrent treatment with vitamins D + E induces a synergistic effect in differentiation toward an osteoblastic lineage.

Effective Wavelength Range in Photobiomodulation for Tooth Movement Acceleration in Orthodontics: A Systematic Review

Objective: The present systematic review aims to establish an effective range of low-level laser therapy wavelengths to accelerate tooth movement in orthodontic treatments. Materials and methods: The electronic literature search was carried out in the following databases: PubMed, ISI Web of Science, Scopus, and Cochrane randomized controlled trials (RCTs). The protocol (CRD42019117648) was registered in PROSPERO. Results: According to PRISMA guidelines and after applying the inclusion criteria, nine RCTs were included. Three blind reviewers independently assessed the methodological quality and evidence level of selected articles. Evidence level classification was established according to the recommendations of SIGN 50 (Scottish Intercollegiate Guidelines Network 2012) and was high quality being ++, acceptable +, low quality -, unacceptable -, reject 0. Conclusions: The majority of RCTs related to accelerating the tooth movement in orthodontic treatments are ideally between 780 and 830 nm wavelengths. The average increase in speed movement calculated as a percentage of the control group in nine studies is 24%. Further studies are necessary to establish the exact dosimeter in photobiomodulation during orthodontic movement.

Photobiomodulation and Pain Reduction in Patients Requiring Orthodontic Band Application: Randomized Clinical Trial

PURPOSE

The aim of this study was to investigate the effect of Photobiomodulation (PBM) in managing orthodontic pain intensity over time in patients requiring band application on upper first molars.

METHODS

Maxillary first molars were banded. In the trial group, each molar received single-session PBM on two buccal and two palatal points (λ = 830 ± 10 nm; 150 mW, 7.5 J/cm2; spot of 0.1 cm2; 5 sec per point), while the control group received a placebo treatment. All patients were asked to answer five pain rating scales to assess pain intensity at 5 minutes and 1, 12, 24, and 72 hours and completed a survey describing the type of pain and its temporal course in the next 7 days.

RESULTS

26 patients (mean age 11.8 years) were randomly assigned to a control or a trial group. The trial group showed significantly lower pain intensities (p < 0.05) at 5 min (M = 0.92, SD = 1.32), 1 h (M = 0.77, SD = 1.01), and 12 h (M = 0.77, SD = 1.54) after band application compared to the control group (5 min: M = 1.62, SD = 1.26; 1 h: M = 1.77, SD = 1.92; and 12 h: M = 1.77, SD = 2.17), whereas no difference between groups (p > 0.05) was found at 24 h (trial: M = 0.62, SD = 1.71; control: M = 1.08, SD = 1.75) and 72 h (trial: M = 0.31, SD = 0.75; control: M = 0.15, SD = 0.55). Patients in the control group reported more frequently the presence of "compressive pain" (58.8%, p < 0.05) from the appliance during the week after the application, while the trial group showed higher frequency of "no pain" (46.2%, p < 0.05). However, PBM did not affect the pain onset (trial: M = 10.86, SD = 26.97; control: M = 5.25, SD = 7.86), peak (trial: M = 15.86, SD = 26.29; control: 6.17, SD = 7.96), and end time (trial: 39.57, SD = 31.33; control: M = 22.02, SD = 25.42) reported by the two groups (p > 0.05).

CONCLUSIONS

PBM might be considered a promising alternative to decrease general pain intensity, although not affecting the typical pain cycle, in terms of the onset, peak, and ending times.

Corticotomy in orthodontic treatment: systematic review

OBJECTIVE

The aim of this study is to evaluate corticotomies effects to accelerate or facilitate dental movements in different kind of orthodontic treatments.

DATA

This report followed the PRISMA Statement. A total of 9 articles were included in review.

SOURCES

Two reviewers performed a literature search up to December 2018 in four databases: PubMed, Web of Science, Scopus and SciELO.

STUDY SELECTION

Controlled clinical trials and randomized controlled clinical trials conducted in human patients and published during the last 10 years in English were eligible to be selected. The articles should give detailed information about the results and treatment parameters. There were no limitations established in terms of the type of malocclusion to be corrected or the type of orthodontic treatment performed.

RESULTS

The methodological quality and evidence of the selected studies was low. Most of the studies observed a statistically significant increase in the rate of dental movement, when performing alveolar corticotomies as coadjuvants of orthodontic treatment; either with the conventional technique or with piezocision. The effect of combining corticotomy with bone grafts was assessed.

CONCLUSIONS

High heterogeneity among studies made it difficult to draw clear conclusions. However, within the limitations of this review, the corticotomy procedures were able to statistically and clinically produce significant temporary decrease in orthodontic tooth movement rate. This technique does not seem to involve major complications compared to conventional orthodontic treatments.

CLINICAL RELEVANCE

The use of this technique can reduce treatment time and therefore the undesirable effects associated with prolonged treatments.

Low-level laser-aided orthodontic treatment of periodontally compromised patients: a randomised controlled trial

Low-level laser irradiation (LLLI) shows effects in orthodontic pain relief and periodontal inflammation control. The aim of this article is to investigate the analgesic and inflammation-modulatory effects of low-level laser irradiation among orthodontic patients with compromised periodontium. A randomised controlled trial with split-mouth design was conducted in 27 adults with treated and controlled chronic periodontitis over 6 months. One side of the dental arch underwent repeated treatment under a 940-nm diode laser (EZlase; Biolase Technology Inc.) with a beam size of 2.8 cm² for 60 seconds at 8.6 J/cm², whilst the other side received pseudo-laser treatment. Laser irradiation was applied repeatedly for 8 times during the first 6 weeks after bracket bonding and monthly thereafter until the end of orthodontic treatment. Subjective pain (assessed by visual analogue scale in pain diary and by chairside archwire activation), periodontal status (assessed by periodontal clinical parameters), cytokines in gingival crevicular fluid (interleukin 1β, prostaglandin E₂, substance P) and periodontopathic bacteria (Porphyromonas gingivalis and Treponema denticola) in supragingival plaque were assessed. The intensity of pain was lower on the laser-irradiated side at multiple follow-up visits (P < 0.05). The pain subsided 1 day earlier on the laser side, with a lower peak value during the first week after initial archwire placement (P < 0.05). The laser side exhibited a smaller reduction in bite force during the first month (mean difference = 3.17, 95% CI: 2.36-3.98, P < 0.05 at 1-week interval; mean difference = 3.09, 95% CI: 1.87-4.32, P < 0.05 at 1-month interval). A smaller increase was observed in the plaque index scores on the laser side at 1-month (mean difference = 0.19, 95% CI: 0.13-0.24, P < 0.05) and in the gingival index scores at the 3-month follow-up visit (mean difference = 0.18, 95% CI: 0.14-0.21, P < 0.05). Laser irradiation inhibited the elevation of interleukin-1β, prostaglandin E₂ and substance P levels during the first month (P < 0.05). However, no intergroup difference was detected in the bacteria levels. Low-level laser irradiation exhibits benefits in pain relief and inflammation control during the early stage of adjunctive orthodontic treatment in periodontally compromised individuals.

Laser-Assisted Orthodontic Tooth Movement in Saudi Population: A Prospective Clinical Intervention of Low-Level Laser Therapy in the 1st Week of Pain Perception in Four Treatment Modalities

Background

This first-in-human study in Saudi orthodontic patients has evaluated the role of low-level laser therapy (LLLT) in pain perception (PP). The outcome of single application of LLLT with 4 different treatment modalities (TM) on PP are evaluated following orthodontic bracket bonding on maxilla.

Materials and Methods

A prospective clinical intervention with implementation of parallel technique in each group, 32 orthodontic patients with ectopic canine requiring fixed orthodontic appliance were enrolled and randomly allocated to the 4 groups: LLLT + self-ligating (SL) bracket, LLLT + conventional (Conv.) bracket, non-LLLT + SL bracket, and non-LLLT + Conv. bracket. Orthodontic bracket bonding from 1st molar to 1st molar and superelastic 0.012 inch NiTi were applied for the maxilla. For each patient, maxillary 1st molar to molar received a single application of LLLT using a 940 nm Ga-Al-As laser device on 5 different points labially/buccally and palatally. Main outcome measure was the degree of PP score during the 1st week of orthodontic tooth movement (OTM) after 4 hours, 24 hours, 3 days, and 7 days of both LLLT and non-LLLT treatment applications. A questionnaire with an 11-point numeric rating scale (NRS) was used for PP.

Results

Mean ± SD of PP in the LLLT + SL group was 3.33 ± 1.4, 3.58 ± 1.06, 2.31 ± 0.67, and 1.89 ± 0.54 in 4 hours, 24 hours, 3 days, and 7 days, respectively. Compared to all 4 TM groups, LLLT groups showed better PP. More statistically significant differences were found in LLLT groups. No harms were encountered.

Limitations

The intervention provider and the patient were not blinded to the intervention.

Conclusion

The LLLT + SL group revealed significantly promising benefits on PP during OTM.

Systematic Review of Delivery Parameters Used in Dental Photobiomodulation Therapy

Objective: This systematic review of published data critically appraises the consistency in the reported delivery parameters used in photobiomodulation (PBM) therapies research within clinical dentistry and makes reporting recommendations for future clinical protocols. Background: Key to the standardization of randomized clinical trials and associated peer-reviewed articles is the disclosure of all laser and light-emitting diode operating parameters. The current status shows a lack of full parameters and significantly impacts on the ability to integrate published data with current and future investigation into clinical PBM therapy. Materials and methods: Search engines, PubMed, Google Scholar, and Cochrane, were scanned for investigation into the effects of PBM therapy research within clinical dentistry. Key words "Low-Level-Laser," "PBM," "Photobiomodulation," "Oral" and "Therapy" were used and a total of 754 articles identified, spanning a period of 9 years and 1 month between February 2009 and March 2018. Only human clinical trials were considered. Fifty-two articles were included in this investigation and the reported basic delivery parameters used in PBM therapies research were considered for each clinical trial. Results: The overall reported basic delivery parameters used in PBM therapies research were too inadequate to be able to be replicated in further studies. These included parameters related to the power meter, beam cross-sectional dynamics, fluence, and wider aspects of dosimetry. Conclusions: The delivery parameters used in PBM therapy research within clinical dentistry, investigated in this study, presented a wide variation in their recording or nonrecording of all significant elements needed to have scientific validity. A constant inconsistency in delivering valid, reliable, PBM therapy doses, to target tissues was also identified. The lack of consensus in delivering a sound protocol for PBM therapy, is partly due to the lack of adequate reported materials and methods, which are essential for replication of individual studies. One way to resolve this problem is for Journals to insist on all comprehensive parameter records, used in PBM therapies, to be part of author guidelines in submitting articles of studies on PBM therapy in clinical dentistry.

Effectiveness of Low-Level Laser Therapy during Tooth Movement: A Randomized Clinical Trial

The present study evaluated the effects of low-level laser therapy (LLLT) by means of a diode laser in accelerating orthodontic tooth movement (OTM). After extraction of the first upper premolars for orthodontic purpose, 82 maxillary canines which needed distalization were analyzed in 41 enrolled patients (21 males, 20 females, mean age 13.4 ± 2.1 years). On all experimental sites, an orthodontic force of 50/N was applied by a nickel-titanium (NiTi) closed coil spring (G&H, Franklin, IN, USA) in order to obtain the space closure. Using a split mouth randomized design, the test side was treated using a diode laser (Wiser Laser Doctor Smile, Brendola, Italy) operating at 810 nm wavelength in continuous wave mode at both the buccal and palatal side on three points/side (distal, medial and mesial) (1 W output power, continuous wave of 66.7 J/cm2, energy density of 8 J) at baseline and at 3, 7, and 14 days and every 15 days until the space closed. On the control side, the opposite selected canine was treated only using orthodontic traction. The primary outcome chosen was the overall time needed to complete the levelling and closing space, measured on a study cast. The secondary outcome chosen was the evaluation of pain levels related to tooth traction, using a Visual Analogue Scale (VAS), recorded at 3, 7, and 14 days after treatments. The mean space closures of the maxillary canines were comparable between groups [Test, 4.56 mm (95% CI 3.9-4.8); Control, 4.49 mm (95% CI 3.8-4.7), p = 0.456]. The laser group yielded less mean time [84.35 ± 12.34 days (95% CI 79.3-86)] to accomplish space closure compared to the control group [97.49 ± 11.44 days (91.7-102.3)] (p < 0.001). The test side showed a significant reduction in the average range of dental pain at 3 [Test, 5.41 (95% CI 5.1-5.6); Control, 7.23 (95% CI 6.9-7.6), p < 0.001], 7 [Test, 4.12 (95% CI 3.8-4.7); Control, 5.79 (95% CI 5.4-5.8), p < 0.001], and at 14 days [Test, 2.31 (95% CI 1.8-2.3); Control, 3.84 (95% CI 3.3-4.2), p < 0.001] after treatment (p < 0.001). This study demonstrates that the use of LLLT therapy was effective in accelerating tooth movement and reducing pain levels related to OTM.

The effect of low-level laser therapy on orthodontically induced root resorption: a pilot double blind randomized controlled trial

Background

The effect of low-level laser therapy (LLLT) on accelerating orthodontic tooth movement has been extensively studied; however, there is limited knowledge on the use of LLLT on orthodontic root resorption.

Objective

To investigate the effect of LLLT on orthodontically induced inflammatory root resorption (OIIRR) and to compare the difference between pulsed and continuous LLLT on OIIRR.

Trial design

Double-blind, single-centre 3-arm parallel split-mouth randomized controlled trial.

Participants

Twenty adolescent patients who required bilateral maxillary first premolar (MFP) orthodontic extractions were recruited from the Sydney Dental Hospital between October 2014 and December 2014.

Intervention

All MFPs were tipped buccally for 28 days to induce OIIRR. The experimental premolars (n = 20) received LLLT and the control premolars (n = 20) received placebo-laser on days 0, 1, 2, 3, 7, 14, and 21. Ten experimental premolars received LLLT via continuous delivery and 10 received pulsed delivery.

Laser parameter

AlGaAs diode laser of 808 nm wavelength, 0.18 W power, 1.6 J per point, and duration of 9s for continuous mode and 4.5 s for pulsed mode.

Outcome

The difference in root resorption crater volume between LLLT and placebo-laser and continuous or pulsed laser delivery after 28 days.

Randomization

Randomization was computer-generated, with allocation concealment by opaque sequentially numbered sealed envelopes.

Blinding

The participants and operator were blinded.

Results

Eighty-eight patients were screened and 20 patients were randomized. Forty premolars were analysed. LLLT resulted in 23 per cent less root resorption compared to the placebo (P = 0.026). Pulsed laser delivery resulted in 5 per cent less root resorption than continuous; however, this was not statistically significant (P = 0.823). No harm was observed.

Conclusion

Teeth treated with LLLT had less total root resorption than placebo-laser. Furthermore, there was minimal difference between pulsed or continuous delivery of LLLT.

Trial Registration

Clinical Trials Registry (ACTRN12616000829415).

Protocol

The protocol was not published before trial commencement.

Low-Level Laser Therapy: A Noninvasive Method of Relieving Postactivation Orthodontic Pain-A Randomized Controlled Clinical Trial

Introduction

Pain is an unavoidable squeal of orthodontic treatment and it is known to decrease patient compliance and eventually affects treatment results. Numerous methods are available in literature to manage orthodontic pain after activation but they have their own limitations. This has led to exploring further options for management of pain.

Aim

The aim of this study was to evaluate the effectiveness of low-level laser therapy (LLLT) in alleviating orthodontic pain after activation.

Materials and Methods

20 subjects were randomly divided into an experimental and a control group. Each participant was given a retraction force of 200 gm/cm²/side. Subjects in the experimental group were exposed to low-level laser light at 980 nm and those in the control group were exposed to red LED light as placebo. The pain perceived after 0 hour, 1 hour, 3 hours, 48 hours, and 1 week of activation was recorded by patient using Visual Analog Scale. Statistical analysis was done using Mann-Whitney test.

Results

Results of the study showed that pain experienced by the subjects after orthodontic activation was higher in experimental group at T₀ than in placebo group. At T₁, T₂, T₄, and T₅, the pain experienced by the subjects was less in the experimental group compared to the placebo group. Pain experienced by the subjects in the experimental group at T₃ was significantly less as compared to those in the placebo group.

Conclusion

A single dose of LLLT at 980nm, 2.5 W/cm², and 600 J is effective in relieving orthodontic pain after activation.

Pain management using photobiomodulation: Mechanisms, location, and repeatability quantified by pain threshold and neural biomarkers in mice

Photobiomodulation (PBM) is a simple, efficient and cost-effective treatment for both acute and chronic pain. We previously showed that PBM applied to the mouse head inhibited nociception in the foot. Nevertheless, the optimum parameters, location for irradiation, duration of the effect and the mechanisms of action remain unclear. In the present study, the pain threshold in the right hind paw of mice was studied, after PBM (810 nm CW laser, spot size 1 or 6 cm² , 1.2-36 J/cm² ) applied to various anatomical locations. The pain threshold, measured with von Frey filaments, was increased more than 3-fold by PBM to the lower back (dorsal root ganglion, DRG), as well as to other neural structures along the pathway such as the head, neck and ipsilateral (right) paw. On the other hand, application of PBM to the contralateral (left) paw, abdomen and tail had no effect. The optimal effect occurred 2 to 3 hours post-PBM and disappeared by 24 hours. Seven daily irradiations showed no development of tolerance. Type 1 metabotropic glutamate receptors decreased, and prostatic acid phosphatase and tubulin-positive varicosities were increased as shown by immunofluorescence of DRG samples. These findings elucidate the mechanisms of PBM for pain and provide insights for clinical practice.

Optimal management of orthodontic pain

Pain is an undesirable side effect of orthodontic tooth movement, which causes many patients to give up orthodontic treatment or avoid it altogether. The aim of this study was to investigate, through an analysis of the scientific literature, the best method for managing orthodontic pain. The methodological aspects involved careful definition of keywords and diligent search in databases of scientific articles published in the English language, without any restriction of publication date. We recovered 1281 articles. After the filtering and classification of these articles, 56 randomized clinical trials were selected. Of these, 19 evaluated the effects of different types of drugs for the control of orthodontic pain, 16 evaluated the effects of low-level laser therapy on orthodontic pain, and 21 evaluated other methods of pain control. Drugs reported as effective in orthodontic pain control included ibuprofen, paracetamol, naproxen sodium, aspirin, etoricoxib, meloxicam, piroxicam, and tenoxicam. Most studies report favorable outcomes in terms of alleviation of orthodontic pain with the use of low-level laser therapy. Nevertheless, we noticed that there is no consensus, both for the drug and for laser therapy, on the doses and clinical protocols most appropriate for orthodontic pain management. Alternative methods for orthodontic pain control can also broaden the clinician's range of options in the search for better patient care.

Effects of single-dose, low-level laser therapy on pain associated with the initial stage of fixed orthodontic treatment: A randomized clinical trial

Objective

The aim of this study was to assess the analgesic effect of a single application of low-level laser therapy (LLLT) on spontaneous pain and pain on chewing after placement of initial archwires.

Methods

Forty-two patients (26 women, 16 men) were randomly recruited for this split-mouth randomized clinical trial. Each patient received super-elastic nickel-titanium (NiTi) initial archwires (0.012, 0.014, 0.016, and 0.018-inch [in]) in the maxilla for leveling and alignment for an interval of 4 weeks between archwires. One side of the mouth was randomly designated as experimental, while the other side served as placebo. After insertion of each archwire, the experimental side was irradiated with a diode laser for 3 seconds each on 5 points facially and palatally per tooth, from the central incisor to first molar. On the placebo side, the laser device was held the same way but without laser application. A numerical rating scale was used to assess the intensity of spontaneous and masticatory pain for the following 7 days. The Mann-Whitney U test was used to compare pain scores between sides.

Results

Patients in the LLLT group exhibited significantly lower mean scores for spontaneous pain after insertion of the initial two archwires (0.012-in and 0.014-in NiTi; p < 0.05), while there was no significant difference for 0.016-in and 0.018-in wires between the LLLT and placebo groups. LLLT significantly reduced chewing pain scores (p < 0.05) for all archwires.

Conclusions

A single dose of LLLT considerably lessened postoperative pain accompanying the placement of super-elastic NiTi wires for initial alignment and leveling.

Potential risks of orthodontic therapy: a critical review and conceptual framework

This review examines some of the potential risks of orthodontic therapy along with their evidence base. The risks of orthodontic treatment include periodontal damage, pain, root resorption, tooth devitalization, temporomandibular disorder, caries, speech problems and enamel damage. These risks can be understood to arise from a synergy between treatment and patient factors. In general terms, treatment factors that can influence risk include appliance type, force vectors and duration of treatment whilst relevant patient factors are both biological and behavioural. Hence, the natural variation between orthodontic treatment plans and patients gives rise to variations in risk. A good understanding of these risks is required for clinicians to obtain informed consent before starting treatment as well as to reduce the potential for harm during treatment. After considering each of these risks, a conceptual framework is presented to help clinicians better understand how orthodontic risks arise and may therefore be mitigated.

Effectiveness of Low-Level Laser Therapy in Reducing Orthodontic Pain: A Systematic Review and Meta-Analysis

Objectives

To assess the effectiveness of low-level laser therapy (LLLT) in reducing orthodontic pain after the application of orthodontic force (OF).

Methods

A systematic search was conducted in the MEDLINE, EMBASE, Scopus, Cochrane Library, Web of Science, and EBSCOhost databases. The study included randomized clinical trials (RCT) which analysed the effectiveness of LLLT in reducing orthodontic pain assessed at 24 and 72 hrs after the application of OF. The risk of bias of the eligible trials was assessed using the Cochrane Collaboration's risk of bias tool. Standard mean difference was calculated and pooled by meta-analysis using random effect models.

Results

Of 467 identified articles, 20 RCT were finally included. In the risk of bias assessments, 13 studies presented a high risk, 5 an unclear risk, and 2 a low risk. The meta-analysis showed that in patients treated with laser versus placebo there was a difference in favour of LLLT in spontaneous pain 24 and 72 hrs after the installation of light archwires and spontaneous pain and chewing pain 24 and 72 hrs after the installation of elastomeric separators.

Conclusions

LLLT proved to be effective in promoting a reduction in spontaneous and chewing pain after the application of OF; however, the poor quality of the evidence requires these results to be treated with caution.

Effect of exogenous retinoic acid on tooth movement and periodontium healing following tooth extraction in a rat model

OBJECTIVES

To evaluate the effect of isotretinoin on orthodontic tooth movement (OTM) and wound healing following exodontia.

SETTING AND SAMPLE POPULATION

Sixteen 40-day-old male Wistar rats were divided into two groups: (a) OTM and (b) tooth extraction (TE) of the upper 1st molar and OTM. The experimental animals were treated with isotretinoin (7.5 mg/kg) and the control animals with oil solution for 37 days.

MATERIALS AND METHODS

The OTM and bone volume were evaluated by the micro-CT and the periodontium healing was assessed by immunohistochemistry for VEGF-C, COX-2 and IL-1ß.

RESULTS

The animals of both groups submitted to the TE showed a statistically significant decrease in the bone volume percentage and increase in OTM. No significant difference of OTM and bone volume was observed between the control and experimental group. However, the alveolar bone of the isotretinoin group revealed more medullary spaces with inflammatory, hematopoietic cells, blood vessels and intense immunolabeling for VEGF-C. This group also showed faster gingival regeneration. No significant difference was observed in the COX-2 and IL-1ß labelings following TE between both groups.

CONCLUSION

The isotretinoin did not affect the OTM nor did it cause an alteration in maxillary bone volume. This exogenous acid may contribute to the acceleration of gingival healing.

CO2 low-level laser therapy has an early but not delayed pain effect during experimental tooth movement

OBJECTIVES

To test the hypothesis that the use of low-level laser therapy (LLLT) reduces elevated pain by controlling the release of neurochemicals during orthodontic tooth movement.

SETTING AND SAMPLE POPULATION

Department of Orthodontics and Dentofacial Orthopedics, Okayama University. Sixty-five Sprague Dawley rats were subjected to tooth movement and LLLT.

MATERIALS AND METHODS

Adult Sprague Dawley rats were used in this study. Groups included day 0 controls, irradiation only controls and with or without irradiation sacrificed at 1, 3, 5, 7 and 14 days after tooth movement (n=5 each, total n=65). Tooth movement was achieved by insertion of an elastic module between molar teeth. Immunohistochemistry for CD-11b, GFAP and c-fos in the brain stem was performed. Stains were quantified by constructing a three-dimensional image using IMARIS, and counted using NEURON TRACER and WinROOF software. Two-way ANOVA followed by a Tukey's post hoc test (P<.05) was used for statistical comparison between groups.

RESULTS

C-fos expression was significantly increased at one and three days after tooth movement. LLLT significantly diminished this increase in c-fos expression only at one day after tooth movement CD-b11 and GFAP expression also significantly increased after tooth movement. No significant change was observed for CD-11b and GFAP expression in the central nervous system upon LLLT.

CONCLUSION

Low-level laser therapy may reduce early neurochemical markers but have no effect on delayed pain neurochemical markers after tooth movement.

Does Low-Level Laser Therapy Enhance the Efficiency of Orthodontic Dental Alignment? Results from a Randomized Pilot Study

OBJECTIVE

To assess if low-level laser therapy (LLLT) enhances the efficiency of orthodontic dental alignment.

BACKGROUND

There is no evidence of the effect of LLLT on the orthodontic treatment time from randomized clinical trials.

METHODS

Thirty-six subjects were included in this interventional pilot study and randomly assigned for treatment with fixed appliance and LLLT (test group) or with fixed appliance only (control group). A single monthly administration of LLLT was performed intraorally using a Diode laser (980 nm, 1 W, continuous wave, total energy density = 150 J/cm²; Doctor Smile-Lambda Spa). The date of brackets bonding (T1) and the date of complete resolution of dental crowding (T2) were recorded. The alignment treatment time was defined in days as T2 - T1. The number of monthly scheduled control visits was also recorded. Treatment time duration was assessed in both groups with the log-rank (Mantel-Cox) Test for survival analysis. Mann-Whitney U tests was used to compare the number of control visits from T1 to T2 between the two groups.

RESULTS

Patients' age, sex, and amount of crowding were equally distributed between the two groups. The alignment treatment time was significantly shorter (p < 0.001) in the tested group (211.8 days) compared to the control (284.1 days). Consequently, control visits (p < 0.001) were lower in the test group (7 visits, median value) compared to the control group (9.5 visits, median value).

CONCLUSIONS

The results of this pilot study suggest that the administration of LLLT might significantly increase the efficiency of orthodontic treatment during dental alignment.

The Potential Use of Pharmacological Agents to Modulate Orthodontic Tooth Movement (OTM)

The biological processes that come into play during orthodontic tooth movement (OTM) have been shown to be influenced by a variety of pharmacological agents. The effects of such agents are of particular relevance to the clinician as the rate of tooth movement can be accelerated or reduced as a result. This review aims to provide an overview of recent insights into drug-mediated effects and the potential use of drugs to influence the rate of tooth movement during orthodontic treatment. The limitations of current experimental models and the need for well-designed clinical and pre-clinical studies are also discussed.

Non-pharmacological interventions for alleviating pain during orthodontic treatment

BACKGROUND

Pain is prevalent during orthodontics, particularly during the early stages of treatment. To ensure patient comfort and compliance during treatment, the prevention or management of pain is of major importance. While pharmacological means are the first line of treatment for alleviation of orthodontic pain, a range of non-pharmacological approaches have been proposed recently as viable alternatives.

OBJECTIVES

To assess the effects of non-pharmacological interventions to alleviate pain associated with orthodontic treatment.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 6 October 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 9), MEDLINE Ovid (1946 to 6 October 2016), Embase Ovid (1980 to 6 October 2016) and EThOS (to 6 October 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing a non-pharmacological orthodontic pain intervention to a placebo, no intervention or another non-pharmacological pain intervention were eligible for inclusion. We included any type of orthodontic treatment but excluded trials involving the use of pre-emptive analgesia or pain relief following orthognathic (jaw) surgery or dental extractions in combination with orthodontic treatment. We excluded split-mouth trials (in which each participant receives two or more treatments, each to a separate section of the mouth) and cross-over trials.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed risk of bias and extracted data. We used the random-effects model and expressed results as mean differences (MD) with 95% confidence intervals (CI). We investigated heterogeneity with reference to both clinical and methodological factors.

MAIN RESULTS

We included 14 RCTs that randomised 931 participants. Interventions assessed included: low-level laser therapy (LLLT) (4 studies); vibratory devices (5 studies); chewing adjuncts (3 studies); brain wave music or cognitive behavioural therapy (1 study) and post-treatment communication in the form of a text message (1 study). Twelve studies involved self-report assessment of pain on a continuous scale and two studies used questionnaires to assess the nature, intensity and location of pain.We combined data from two studies involving 118 participants, which provided low-quality evidence that LLLT reduced pain at 24 hours by 20.27 mm (95% CI -24.50 to -16.04, P < 0.001; I² = 0%). LLLT also appeared to reduce pain at six hours, three days and seven days.Results for the other comparisons assessed are inconclusive as the quality of the evidence was very low. Vibratory devices were assessed in five studies (272 participants), four of which were at high risk of bias and one unclear. Chewing adjuncts (chewing gum or a bite wafer) were evaluated in three studies (181 participants); two studies were at high risk of bias and one was unclear. Brain wave music and cognitive behavioural therapy were evaluated in one trial (36 participants) assessed at unclear risk of bias. Post-treatment text messaging (39 participants) was evaluated in one study assessed at high risk of bias.Adverse effects were not measured in any of the studies.

AUTHORS' CONCLUSIONS

Overall, the results are inconclusive. Although available evidence suggests laser irradiation may help reduce pain during orthodontic treatment in the short term, this evidence is of low quality and therefore we cannot rely on the findings. Evidence for other non-pharmacological interventions is either very low quality or entirely lacking. Further prospective research is required to address the lack of reliable evidence concerning the effectiveness of a range of non-pharmacological interventions to manage orthodontic pain. Future studies should use prolonged follow-up and should measure costs and possible harms.

Bioglass in Alveolar Bone Regeneration in Orthodontic Patients: Randomized Controlled Clinical Trial

This study was designed as a split-mouth randomized controlled clinical trial to evaluate the effects of a novel bioactive glass scaffold-tailored amorphous multiporous (TAMP)-for the preservation of alveolar bone following tooth extraction in class II orthodontic patients. TAMP scaffolds were prepared and sterilized. Patients were screened for eligibility, and 6 patients accounting for 14 extraction sockets were included in this stage. Sockets were randomly allocated to either control (left empty) or test (grafted with TAMP scaffold particles). Follow-up was done after 1, 2, 4, 8, and 12 to 17 wk with digital periapical radiographs to evaluate changes in crestal bone height and bone mineral density (BMD), 3-dimensional volumetric analysis of impression casts, and histologic analysis of core biopsies. Furthermore, alveolar bone marrow mesenchymal stem cells were cultured from control and test sockets following biopsy retrieval to evaluate the ability of TAMP bioactive glass scaffolds to recruit host progenitor cells. Results showed that sockets grafted with TAMP bioactive glass scaffolds better preserved height after 3 mo where mesially 57.1% of test cases showed preservation of socket height, compared with 28.6% of control cases. Distally, this was 42.9% of test cases versus none of the control cases. Regarding BMD, the test sides had higher BMD in all 3 sections of the socket, with the greatest reduction in BMD found in the coronal third. Results were not statistically significant. Histologically, sockets grafted with TAMP bioactive glass scaffolds showed a distinct pattern of bone healing characterized by vertical trabeculae and large vascularized marrow spaces with sockets showing corticalization. Volumetric analysis showed a better preservation of socket contour with TAMP bioactive glass scaffolds. TAMP bioactive glass scaffolds appeared to enhance the recruitment of stem cells from the grafted sockets. In conclusion, TAMP scaffolds appear to better preserve alveolar bone following extraction and allow for a more active bone modeling and remodeling process( ClinicalTrials.gov identifier:NCT01878084). Knowledge Transfer statement: The results of this study set the stage for the recommended use of novel biomimetic scaffolds, such as the tailored amorphous multiporous bioactive glass for preservation of the socket following extraction. This can be valuable for patients and clinicians alike when deciding on long-term prosthetic alternatives that not only result in immediate bone preservation but will accommodate the dynamic nature of bone.

Efficacy of low-level laser therapy in accelerating tooth movement, preventing relapse and managing acute pain during orthodontic treatment in humans: a systematic review

BACKGROUND

Recently low-level laser therapy (LLLT) has been proposed to improve orthodontic treatment. The aims of this systematic review were to investigate the scientific evidence to support applications of LLLT: (a) to accelerate tooth movement, (b) to prevent orthodontic relapse and (c) to modulate acute pain, during treatment with fixed appliances in children and young adults.

METHODS

To ensure a systematic literature approach, this systematic review was conducted to Goodman's four step model. Three databases were searched (Medline, Cochrane Controlled Clinical Trials Register and Scitation), using predetermined search terms. The quality of evidence was rated according to the GRADE system.

RESULTS

The search identified 244 articles, 16 of which fulfilled the inclusion criteria: three on acceleration of tooth movement by LLLT and 13 on LLLT modulation of acute pain. No study on LLLT for prevention of relapse was identified. The selected studies reported promising results for LLLT; elevated acceleration of tooth movement and lower pain scores, than controls. With respect to method, there were wide variations in type of laser techniques.

CONCLUSIONS

The quality of evidence supporting LLLT to accelerate orthodontic tooth movement is very low and low with respect to modulate acute pain. No studies met the inclusion criteria for evaluating LLLT to limit relapse. The results highlight the need for high quality research, with consistency in study design, to determine whether LLLT can enhance fixed appliance treatment in children and young adults.

Evaluation of the use of low-level laser therapy in pain control in orthodontic patients: A randomized split-mouth clinical trial

OBJECTIVE

To evaluate the effect of using low-level laser therapy (LLLT) to control pain and discomfort during orthodontic treatment.

MATERIALS AND METHODS

A randomized, split-mouth clinical trial was conducted with 30 volunteers in need of orthodontic treatment, of both genders, aged between 18 and 40 years, who were randomly divided into two groups. One hemiarch was considered the exposed group (EG) and the other, the placebo group (PG). Both groups had elastic separators placed mesially and distally to the first molars of the two hemiarches at different times. The EG received an AIGaAs diode LLLT (810 nm, 100 mW, 2J/cm(2)) application for 15 seconds per point (interdental papilla at the mesial, distal, and near the root apex) immediately after separator placement on the maxillary right side. The PG also had elastics placed around the maxillary right molars, but received only simulated LLLT application. The elastics were left in place for 5 days, and after a waiting period of 1 week, they were inserted on the left side in both groups; however, the order of laser application was changed. While the separator remained in place, the patient marked his degree of perceived discomfort on a Visual Analog Scale (VAS) at 5 minutes (T0), 24 hours (T1), and 120 hours (T2), after LLLT application.

RESULTS

A statistically significant difference was observed (P < .005) in reducing discomfort in the exposed group compared with the placebo group. This reduction of discomfort in the EG was observed at all time intervals.

CONCLUSIONS

A sincle AIGaAs diode LLLT application may be indicated for the control or reduction of pain in the early stages of orthodontic treatment.

Intraoral photobiomodulation-induced orthodontic tooth alignment: a preliminary study

BACKGROUND

Numerous strategies have been proposed to decrease orthodontic treatment time. Photobiomodulation (PBM) has previously been demonstrated to assist in this objective. The aim of this study was to test if intraoral PBM increases the rate of tooth alignment and reduces the time required to resolve anterior dental crowding.

METHODS

Nineteen orthodontic subjects with Class I or Class II malocclusion and Little's Irregularity Index (LII) ≥ 3 mm were selected from a pool of applicants, providing 28 total arches. No cases required extraction. The test group (N = 11, 18 arches, 10 upper, 8 lower) received daily PBM treatment with an intraoral LED device (OrthoPulse™, Biolux Research Ltd.) during orthodontic treatment, while the control group (N = 8, 10 arches, 3 upper, 7 lower) received only orthodontic treatment. The PBM device exposed the buccal side of the gums to near-infrared light with a continuous 850-nm wavelength, generating an average daily energy density of 9.5 J/cm(2). LII was measured at the start (T0) of orthodontic treatment until alignment was reached (T1, where LII ≤ 1 mm). The control group was mostly bonded with 0.018-in slot self-ligating SPEED brackets (Hespeler Orthodontics, Cambridge, ON. Canada), while conventionally-ligating Ormco Mini-Diamond twins were used on the PBM group (Ormco, Glendora, Calif. USA). Both groups progressed through alignment with NiTi arch-wires from 0.014-in through to 0.018-in (Ormco), with identical arch-wire changes. The rate of anterior alignment, in LII mm/week, and total treatment time was collected for both groups. Cox proportional hazards models were used to compare groups and while considering age, sex, ethnicity, arch and degree of crowding.

RESULTS

The mean alignment rate for the PBM group was significantly higher than that of the control group, with an LII change rate of 1.27 mm/week (SD 0.53, 95 % CI ± 0.26) versus 0.44 mm/week (SD 0.20, 95 % CI ± 0.12), respectively (p = 0.0002). The treatment time to alignment was significantly smaller for the PBM group, which achieved alignment in 48 days (SD 39, 95 % CI ± 39), while the control group took 104 days (SD 55, 95 % CI ±19, p = 0.0053) on average. These results demonstrated that intraoral PBM increased the average rate of tooth movement by 2.9-fold, resulting in a 54 % average decrease in alignment duration versus control. The average PBM compliance to daily treatments was 93 % during alignment.

CONCLUSIONS

Under the limitations of this study, the findings suggest that intraoral PBM could be used to decrease anterior alignment treatment time, which could consequently decrease full orthodontic treatment time. However, due to its limitations, further research in the form of a large, randomized trial is needed.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02267837 . Registered 10 October 2014.

A randomized clinical trial comparing the efficacy of bite wafer and low level laser therapy in reducing pain following initial arch wire placement

Background and aims: This study aimed to evaluate the efficacy of ibuprofen, bite wafer and low power red and infrared lasers in orthodontic pain management. Subjects and methods: One hundred subjects were randomly assigned to 5 groups of 20 each. The patients in each group received one of the following treatments after the placement of fixed orthodontic appliances: 1. placebo medication, 2. ibuprofen, 3. bite wafer, 4. irradiation from a low level red laser (LLRL; 660 nm, 200 mW, 1 J/point, 6 points), 5. irradiation from a low level infrared laser (LLIL; 810 nm, 200 mW, 1 J/point, 6 points). A Visual Analogue Scale (VAS) was used to record pain intensity while chewing, biting, fitting front teeth, and fitting back teeth at 2 hours, 6 hours, bedtime, 24 hours, 2 days, 3 days and 7 days following arch wire placement. Results: Significant between-group differences were found in pain at chewing, biting, fitting front teeth and fitting back teeth at all time points (p<0.001). Generally, VAS scores in the LLIL, ibuprofen and bite wafer groups were close to each other and significantly lower than those in the LLRL and control groups (p<0.05), which showed comparable pain level at most intervals. The infrared laser group (LLIL) showed significantly lower pain than all other groups at some points over the experiment (p<0.05). Conclusions: A single irradiation from a low level infrared laser proved to be the best strategy for orthodontic pain control. Alternatively, chewing on a bite wafer could be recommended. These methods should be considered as suitable alternatives for ibuprofen in orthodontic patients.

Supplemental vibrational force does not reduce pain experience during initial alignment with fixed orthodontic appliances: a multicenter randomized clinical trial

This prospective randomized trial investigated the effect of supplemental vibrational force on orthodontic pain during alignment with fixed-appliances. Eighty-one subjects < 20 years-old undergoing extraction-based fixed-appliance treatment were randomly allocated to supplementary (20-minutes/day) use of an intra-oral vibrational device (AcceleDent^®) (n = 29); an identical non-functional (sham) device (n = 25) or fixed-appliances only (n = 27). Each subject recorded pain intensity (using a 100-mm visual-analogue scale) and intake of oral analgesia in a questionnaire, following appliance-placement (T1) and first-adjustment (T2) for 1-week (immediately-after, 4, 24, 72-hours and at 1-week). Mean maximum-pain for the total sample was 72.96 mm [SD 21.59; 95%CI 68.19–77.74 mm] with no significant differences among groups (P = 0.282). Subjects taking analgesics reported slightly higher maximum-pain although this was not significant (P = 0.170). The effect of intervention was independent of analgesia (P = 0.883). At T1 and T2, a statistically and clinically significant increase in mean pain was seen at 4 and 24-hours, declining at 72-hours and becoming insignificant at 1-week. For mean alignment-rate, pain-intensity and use of analgesics, no significant differences existed between groups (P > 0.003). The only significant predictor for mean pain was time. Use of an AcceleDent vibrational device had no significant effect on orthodontic pain or analgesia consumption during initial alignment with fixed appliances.

Effect of low-level laser therapy on irradiated parotid glands--study in mice

The objective of this study was to evaluate the effect of low-level laser therapy (LLLT) on radiotherapy-induced morphological changes and caspase-3 immunodetection in parotids of mice. Forty-one Swiss mice were divided into control, radiotherapy, 2- and 4-J laser groups. The experimental groups were exposed to ionizing radiation in a single session of 10 Gy. In the laser groups, a GaAlAs laser (830 nm, 100 mW, 0.028  cm2, 3.57  W/cm2) was used on the region corresponding to the parotid glands, with 2-J energy (20 s, 71  J/cm2) or 4 J (40 s, 135  J/cm2) per point. LLLT was performed immediately before and 24 h after radiotherapy. One point was applied in each parotid gland. The animals were euthanized 48 h or 7 days after radiotherapy and parotid glands were dissected for morphological analysis and immunodetection of caspase-3. There was no significant difference between groups in the immunodetection of caspase-3, but the laser groups had a lower percentage compared to the radiotherapy group. LLLT promoted the preservation of acinar structure, reduced the occurrence of vacuolation, and stimulated parotid gland vascularization. Of the two LLLT protocols, the one using 4 J of energy showed better results.

Effect of single-dose low-level helium-neon laser irradiation on orthodontic pain: a split-mouth single-blind placebo-controlled randomized clinical trial

BACKGROUND

Pain is the most common complication of orthodontic treatment. Low-level laser therapy (LLLT) has been suggested as a new analgesic treatment free of the adverse effects of analgesic medications. However, it is not studied thoroughly, and the available studies are quite controversial. Moreover, helium neon (He-Ne) laser has not been assessed before.

METHODS

This split-mouth placebo-controlled randomized clinical trial was performed on 16 male and 14 female orthodontic patients requiring bilateral upper canine retraction. The study was performed at a private clinic in Sari, Iran, in 2014. It was single blind: patients, orthodontist, and personnel were blinded of the allocations, but the laser operator (periodontist) was not blinded. Once canine retractor was activated, a randomly selected maxillary quarter received a single dose of He-Ne laser irradiation (632.8 nm, 10 mw, 6 j/cm(2) density). The other quarter served as the placebo side, treated by the same device but powered off. In the first, second, fourth, and seventh days, blinded patients rated their pain sensed on each side at home using visual analog scale (VAS) questionnaires. There was no harm identified during or after the study. Pain changes were analyzed using two- and one-way repeated-measures ANOVA, Bonferroni, and t-test (α = 0.01, β > 0.99). This trial was not registered. It was self-funded by the authors.

RESULTS

Sixteen males and 11 females remained in the study (aged 12-21). Average pain scores sensed in all 4 intervals on control and laser sides were 4.06 ± 2.85 and 2.35 ± 1.77, respectively (t-test P < 0.0001). One-way ANOVA showed significant pain declines over time, in each group (P < 0.0001). Two-way ANOVA showed significant effects for LLLT (P < 0.0001) and time (P = <0.0001).

CONCLUSIONS

Single-dose He-Ne laser therapy might reduce orthodontic pain caused by retracting maxillary canines.

[Bone formation and corticotomy-induced accelerated bone remodeling: can alveolar corticotomy induce bone formation?]

Current orthodontic treatments must answer an increasing demand for faster yet as efficient treatments, especially in adult patients. These past years, the amelioration of orthodontic, anesthetic and orthognathic surgery techniques have allowed considerable improvement of orthodontico-surgical treatments and of adult orthodontic treatments. Alveolar corticotomy (an example of such techniques) accelerates orthodontic tooth movements by local modifications of bone metabolism, inducing a transient osteopenia. This osteopenia allows greater tooth movements than conventional techniques. Whereas there is a growing understanding of the underlying biological mechanisms of alveolar corticotomies, there is little data regarding the osteogenic potential of such technique. In the present article, we review the literature pertaining to alveolar corticotomies and their underlying biological mechanisms and present a clinical case underlining the osteogenic potential of the technique.

The effectiveness of low-level diode laser therapy on orthodontic pain management: a systematic review and meta-analysis

To assess the effectiveness of diode low-level laser therapy (LLLT) for orthodontic pain control, a systematic and extensive electronic search for randomised controlled trials (RCTs) investigating the effects of diode LLLT on orthodontic pain prior to November 2014 was performed using the Cochrane Library (Issue 9, 2014), PubMed (1997), EMBASE (1947) and Web of Science (1956). The Cochrane tool for risk of bias evaluation was used to assess the bias risk in the chosen data. A meta-analysis was conducted using RevMan 5.3. Of the 186 results, 14 RCTs, with a total of 659 participants from 11 countries, were included. Except for three studies assessed as having a ‘moderate risk of bias’, the RCTs were rated as having a ‘high risk of bias’. The methodological weaknesses were mainly due to ‘blinding’ and ‘allocation concealment’. The meta-analysis showed that diode LLLT significantly reduced orthodontic pain by 39 % in comparison with placebo groups (P = 0.02). Diode LLLT was shown to significantly reduce the maximum pain intensity among parallel-design studies (P = 0.003 versus placebo groups; P = 0.000 versus control groups). However, no significant effects were shown for split-mouth-design studies (P = 0.38 versus placebo groups). It was concluded that the use of diode LLLT for orthodontic pain appears promising. However, due to methodological weaknesses, there was insufficient evidence to support or refute LLLT’s effectiveness. RCTs with better designs and appropriate sample power are required to provide stronger evidence for diode LLLT’s clinical applications.

Tooth movement alterations by different low level laser protocols: a literature review

Low-Level Laser Therapy (LLLT) provides several benefits for patients receiving orthodontic treatment. According to some literatures, Orthodontic Tooth Movement (OTM) can be enhanced but some investigators have reported contradictory results. This article reviews the literature regarding the different aspects of the use of LLLT on OTM and its alterations. The general data regarding the study design, sample size, wavelength (nm), power (mW), and duration were extracted and recorded independently. Electronic databases of PubMed and ScienceDirect from January 2009 to August 2014 were searched. Also Google Scholar and grey literature was searched for relevant references. Some investigators found that the amount of tooth movement in the Low-Energy Laser Irradiation (LELI) group was significantly greater than in the nonirradiation group by the end of the experimental period. Low-level laser irradiation accelerates the bone remodeling process by stimulating osteoblastic and osteoclastic cell proliferation and function during orthodontic tooth movement. But some researchers have reported that no statistical differences in the mean rate of tooth movement were noted between low energy and high energy experimental sides and their controls. Some evidence shows that low-level laser irradiation accelerates the bone remodeling process and some evidence shows that LLLT has not effect on OTM. In some investigations no statistical differences in the mean rate of tooth movement can be seen between low energy and high energy experimental sides and their controls. It has been shown by authors that laser irradiation can reduce the amount of OTM and a clinical usage for the inhibitory role of low level laser irradiation is enforcing the anchorage unit.

Systematic literature review: influence of low-level laser on orthodontic movement and pain control in humans

OBJECTIVE

The purpose of this study was to systematically review the literature to check the influence of low-level laser (LLL) on orthodontic movement and pain control in humans, and what dose ranges are effective for pain control and increased speed of orthodontic movement.

METHODS

Computerized and manual searches were conducted up to January 4, 2014 for clinical studies that addressed these objectives. The selection criteria required that these studies (1) be prospective controlled clinical trials (CCT) and randomized clinical trials (RCT); (2) only use LLL in both infrared and visible red wavelengths, a laser with emission of constant wave; (3) have all main parameters of dose described, or at least conditions for calculation of the energy, in Joules; and (4) be published in Portuguese, English, or Spanish and be meta-analyses.

RESULTS

Seven studies met the eligibility criteria for orthodontic movement/LLL and 11 studies met the inclusion criteria for analgesia/LLL, totaling 18 prospective randomized studies that were selected for detailed analysis. The most common and effective energy input was the interval of 0.2-2.2 J per point/2-8 J per tooth at a frequency of application 1-5 days per month to accelerate the orthodontic movement. For pain control, the recommended energy per points varied from 1-2 J when only one tooth was irradiated to 0.5-2.25 J per point when all teeth in the dental arch were irradiated.

CONCLUSIONS

LLL seems to have a demonstrated efficacy, but further studies are warranted to determine the best protocols with regard to energy and frequency.

Low-level laser therapy for orthodontic pain: a systematic review

This review aimed to evaluate the clinical outcome of different lasers management on orthodontic pain. Cochrane Library (Issue 7, 2014) and MEDLINE (1966-2014.7) were searched to collect randomized controlled trials on lasers for orthodontic pain. Studies meeting the inclusion criteria were systematically evaluated. The Cochrane Collaboration tools RevMan5.1.7 and GRADEpro 3.6 were used in this systematic review and meta-analysis. As a result, 11 randomized controlled trials (RCTs) studying on low-level laser therapy (LLLT) for orthodontic pain control were included. Meta-analysis and risk of bias assessment were implemented using RevMan5.1.7, and level of evidence assessments was measured by GRADEpro 3.6. In the outcome of the score of the most painful day, the comparison of laser versus placebo (pain associated with tooth movement) demonstrated that LLLT reduced the pain score significantly compared with placebo groups (MD = -4.39, 95% CI range -5.9--2.88, P < 0.00001). In the same way, the most painful day was significantly brought forward in laser versus control group (MD = -0.42, 95% CI range -0.74--0.10, P = 0.009). Furthermore, the outcome of the end of pain day showed a trend of pain termination earlier in laser versus control and placebo groups, but without statistical significance (MD = -1.37, 95% CI range -3.37-0.64, P = 0.18 and MD = -1.04, 95% CI range -4.22-2.15, P = 0.52). However, for the reason of downgrade factors, all the GRADE level of evidences of eight comparisons for three outcomes showed a very low quality. Therefore, for the methodological shortcomings and risk of bias of RCTs included, insufficient evidence was submitted to judge whether LLLT was effective in relieving orthodontic pain. Further and more perfect researches should be done in order to recommend LLLT as a routine method for orthodontic pain.

Effect of low level laser therapy on dental pulp during orthodontic movement

AIM

To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp.

METHODS

Histologically treated samples from eight human healthy premolar teeth obtained from the middle root level were distributed in four groups: group 1 (G1) absolute control; group 2 (G2) only laser irradiation; group 3 (G3) exposed only to orthodontics; and group 4 (G4) treated with orthodontics and laser. Laser treatment was performed at 830 nm wavelength, 100 mW (energy 80 J/cm(2), 2.2 J), for 22 s in the vestibular surface and 22 s in the palatal surface, 1 mm away from the dental root mucosa. Three staining methods were performed: hematoxylin-eosin (HE), Masson's Trichrome method and Gomori's method.

RESULTS

The pulp histology parameters were evaluated and the results classified in to 3 parts: an inflammatory response, soft tissue response (dental pulp) and hard tissue response (dentin and predentin). There was no inflammation (chronic or acute) in any of the evaluated groups. The zones of pulp necrosis were found in one premolar of G3 and in one of G4; in groups G2 and G4 there was higher angiogenesis than in the other two groups. G4 group presented the highest level of vascularization. A reduced nerve density was observed in G3. A G2 specimen showed increased nerve density. A higher rate of calcification was observed in G1 compared to G2. Denticles, either real or false, were observed in G1, G2 and G3. Sclerosis of dentin and focal dentin loss was observed among all the groups. Secondary dentin was present in one sample in G1 and G2. A necrosis zone was found in one sample of G3 and G4. No differences between groups were observed in the odontoblast irregularity layer but the layer was wider in the group treated with laser only. A notable difference was detected in reduction of the cell-free layer between the groups G1 and G4. The findings in pulp tissue favor its adaptative response against dental movement induced by orthodontics. No definitive conclusions may be derived as this is a pilot study.

CONCLUSION

The protocol described here was shown to be an effective method to evaluate changes in dental pulp submitted to low level laser in teeth under orthodontic movement.