Tooth Movement in Orthodontic Treatment with Low-Level Laser Therapy: A Systematic Review of Human and Animal Studies

Patient-Reported Outcome Measures of Flapless Corticotomy with Low-Level Laser Therapy in En Masse Retraction of Upper Anterior Teeth: A Three-Arm Randomized Controlled Trial

(1) Background: This study aimed to compare patient-reported outcome measures when accelerating en masse retraction between the piezocision procedure and the subsequent application of low-level laser therapy (FC+LLLT), with the piezocision alone (FC), and in a control group. (2) Methods: A three-arm randomized controlled trial (RCT) was conducted involving 60 patients (41 females and 19 males) with Class II division I malocclusion. The en masse retraction was performed using NiTi closed coil springs attached to miniscrews. The LLLT was performed using an 808 nm Ga-Al-As diode laser. Patient responses regarding pain, discomfort, swelling, and chewing difficulties were reported at ten assessment points. (3) Results: The greatest pain levels were observed 24 h after the application of force during the first and third months of retraction. The mean pain, discomfort, swelling, and chewing difficulties were significantly smaller in the control group than in the FC and FC+LLLT groups. High satisfaction levels were reported in all three groups (p < 0.05). (4) Conclusions: The accelerated en masse retraction via piezocision, followed by a small course of LLLT, was accompanied by significantly fewer pain, discomfort, and chewing difficulties than the control group. LLLT is a valuable addition to piezocision, with an improved patient experience.

In Vitro Effect of Photobiomodulation Therapy with 980 nm Diode Laser on Gene Expression of Key Regulators of Bone Remodeling by Human Periodontal Ligament Cells under Mild Orthodontic Forces

This study investigated the effect of photobiomodulation (PBM) with 980 nm diode laser as monotherapy and in combination with compressive and tensile orthodontic forces on expression of osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), sclerostin (SOST) and periostin (POSTN), by human periodontal ligament cells. Isolated cells were cultured and subjected to either tensile (10% elongation) or compressive forces (25 g cm-2 ) for 24 and 48 h. Subsequently, the cells received PBM (100 mW power, 3 or 6 J cm-2 energy density) immediately after load cycle. RT-PCR was applied to assess the genes expression. Data were analyzed by one-way ANOVA, followed by post hoc Tukey test (P ≤ 0.05). We found that PBM in combination with orthodontic forces led to upregulation of bone resorption genes (RANKL and SOST) at the pressure side and their downregulation at the tension side. The expression of osteogenic genes (OPG and POSTN) increased at the tension side and decreased at the pressure side. PBM alone did not affect gene expression. In conclusion, these findings suggest that this PBM protocol may be effective in enhancement of the gene expression in favor of bone remodeling acceleration that should be confirmed in future animal and human studies.

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.

Investigating the Effectiveness of Low-Level Laser in Reducing Root Resorption of the Upper Incisors During Intrusion Movement Using Mini-Implants in Adult Patients With Deep Overbite: A Randomized Controlled Clinical Trial

BACKGROUND

Deep bite is a common characteristic of malocclusion, and many methods are used to treat it, including mini-implants used for the intrusion of the upper incisors. Orthodontically induced inflammatory root resorption (OIIRR) is an inevitable and unexpected side effect of orthodontic therapy. However, resorption of the root could be affected by the type of tooth movement, such as intrusion. Several studies have indicated the effectiveness of low-level laser therapy (LLLT) in accelerating orthodontic movement, but studies that have evaluated the role of this laser in reducing the risk of OIIRR have been limited. This trial aimed to investigate the effectiveness of LLLT in reducing the resorption of the roots of the upper incisors during their intrusion in the context of deep bite correction.

MATERIALS AND METHODS

Thirty patients (13 males, 17 females; mean age 22.4±3.37 years) with deep overbite were recruited and allocated to the laser or the control groups. Mini-implants were inserted between the roots of the upper central incisors and the lateral incisors from the labial aspect at the gingival-mucosal junction on both sides with a force of 40 g on each side through an NiTi coil spring. A low-level laser (Ga-Al-As) with 808 nm wavelength in a continuous mode, with the parameters 250 milliwatt power output, 4 Joules/point energy density, and 16 seconds irradiation per point, was applied to the root of each of the upper incisors. The laser was applied on the first day of the upper incisor intrusion (T1), then on days 3, 7, and 14 of the first month. In the second month, the laser was applied every 15 days, adjusting the spring strength every four weeks until the end of the intrusion stage (T2), which was determined by reaching a normal overbite. As for patients in the control group, the strength of the nickel-titanium springs was adjusted every four weeks to the required strength of 40 g on each end until reaching a normal overbite.

RESULTS

There was a volumetric decrease in both groups' upper central and lateral incisors roots, and this decrease was statistically significant (P<0.001). However, the difference between the two groups was not statistically significant in each central and lateral incisor volume root (P=0.345 and 0.263 for U1 and U2, respectively). Also, both groups had a linear decrease in upper central and lateral incisors roots, which was statistically significant (P<0.001). At the same time, the difference between the two groups was not statistically significant in each central and lateral incisor root length (P=0.343 and 0.461 for U1 and U2, respectively).

CONCLUSION

The low-level laser irradiation using the current protocol did not significantly affect the amount of root resorption induced by incisor intrusion in the experimental group compared to the control group.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I ² = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Orthodontic Bracket Removal Using LASER-Technology-A Short Systematic Literature Review of the Past 30 Years

Background: Since fixed orthodontic treatment is widely spread and one of its inconveniences is bracket removal, as this affects enamel integrity as well as being a cause of discomfort to the patient, studies have searched for the most adequate bracket removal technique, many of them focusing on using laser-technology. Methods: Our review focused on articles published investigating methods of orthodontic bracket removal using laser technology in the last 30 years. Results: 19 relevant studies were taken into consideration after a thorough selection. Different types of laser devices, with specific settings and various testing conditions were tested and the investigators presented their pertinent conclusions. Conclusions: Most studies were performed using ceramic brackets and the best results in terms of prevention of enamel loss, temperature stability for the tooth as well as reduced chair time were obtained with Er:YAG lasers.

Evaluation of the acceleration, skeletal and dentoalveolar effects of low-level laser therapy combined with fixed posterior bite blocks in children with skeletal anterior open bite: A three-arm randomised controlled trial

OBJECTIVES

To evaluate the effectiveness of the low-level laser therapy (LLLT) in accelerating the early treatment of the skeletal anterior open bite (AOB) and to evaluate the associated skeletal and dentoalveolar changes.

MATERIALS AND METHODS

A three-arm, parallel-group, randomized controlled trial was conducted on 42 patients aged 8-10 years with skeletal AOB. Patients were randomly allocated to three groups: the fixed posterior bite block+low-level laser therapy (FPBB+LLLT) group; the fixed posterior bite block (FPBB) group; and the untreated control group (UCG) in a 1:1:1 allocation ratio. The LLLT dose in the FPBB+LLLT group was applied using 808-nm wavelength Ga-Al-As semiconductor laser device with the energy of 4-joules/point and irradiation time of 16 seconds/point. LLLT was applied in the first visit; then, it was applied on day 3, 7 and 14 of the first month. Afterwards, it was applied every 15 days until the end of the treatment. Lateral cephalometric images were taken at the beginning of the treatment (T0) and at the end of the active phase (T1). The primary outcome measures were the overall time needed to correct the AOB and the skeletal and dentoalveolar changes.

RESULTS

The correction of the AOB required significantly less mean time in the FPBB+LLLT group compared to the FPBB group (x̅=7.07, x̅=9.42 months, respectively; P=0.001). The mean upper first molar intrusion in the FPBB+LLLT group was 1.21mm and significantly greater than that of the FPBB group (0.82mm; P=0.018). However, there was a slight mean extrusion of the upper first molar in the UCG (0.32mm).

CONCLUSIONS

The overall time needed to correct the AOB was shorter in the FPBB+LLLT group. The LLLT appeared to be effective in accelerating orthodontic tooth movement. FPBB alone or LLLT were effective in the early treatment of anterior open bite (AOB). The two interventional groups produced similar dentoalveolar and skeletal changes; most of which were dentoalveolar in the correction of the anterior open bite.

Efficacy and safety of different interventions to accelerate maxillary canine retraction following premolar extraction: A systematic review and network meta-analysis

Decreasing orthodontic treatment duration is at the forefront of innovation for clinical orthodontics. This network meta-analysis aimed to determine the relative efficacy and safety of treatments for accelerated orthodontic tooth movement (OTM) in patients undergoing extraction of maxillary first premolars followed by canine retraction in any orthodontic setting. MEDLINE, EMBASE, Cochrane CENTRAL, CINAHL and SCOPUS were searched (from inception to 20 April 2020). Study selection and data extraction were performed in duplicate. Eligible randomized controlled trials (RCTs) were meta-analysed to estimate the rate of tooth movement, 95% credible interval and surface under the cumulative ranking curve (SUCRA) in the first 3 months following the application of the adjunctive accelerative method. Eligible RCTs were assessed by Cochrane risk of bias tool, and quality of evidence was assessed by GRADE approach, obtained from CINeMA web application. Interventions were ranked for efficacy and reviewed for safety. Nineteen studies pertaining to eight interventions, with data from 415 patients were included. Quality of evidence was very low to moderate. Very low-to low-quality evidence suggests that corticotomy is an efficacious and safe adjunctive treatment to accelerate OTM in comparison with conventional treatment in the first 2 months of treatment. Low-quality evidence suggests that piezocision and micro-osteoperforations (MOP) are efficacious and safe adjunctive treatments only in the first month of treatment. Frequent MOP in conjunction with low-level laser therapy appeared to be an efficacious and safe adjunctive treatment only in the first month following its initial application but not thereafter.

The effect of intra-oral LED device and low-level laser therapy on orthodontic tooth movement in young adults: A randomized controlled trial

INTRODUCTION

This randomized controlled clinical trial aimed to assess the effect of LED⁵ and LLLT⁶ in a three-arm parallel setting.

METHODS

Sixty patients who needed the maxillary first premolar extraction were allocated to three groups using the stratified block randomization method. In the LED group, a custom-made device with a wavelength of 640nm and a power density of 40 mW/cm² was used 5min/day. In the laser group, Ga Al As⁷ laser with a wavelength of 810nm and a power of 100 mW was used on days 0, 3, 30, and 60 each time for 18seconds. Patients in the control group received placebo treatment as the laser group protocol, using a coated light cure device. Models were made at baseline and monthly until the end of the retraction. The rate of canine retraction was the primary outcome, while canine rotation and pain were secondary outcomes. The final data were anonymous for the outcome assessor and statistical consultant. Data were analyzed per protocol using a linear mixed model.

RESULTS

The rate of canine retraction significantly increased by 60.8% in the laser group, while it increased not significantly by 26% in the LED group compared with the control group. There was no significant difference among the groups in terms of tooth rotation and pain.

CONCLUSIONS

LLLT can accelerate orthodontic tooth movement (OTM). LED with the present setting couldn't increase the rate of OTM. LLLT and LED did not affect canine rotation or pain.

TRIAL REGISTRATION

IRCT20120220009086N4. On 1 June 2019 was retrospectively registered.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis

AIM AND BACKGROUND

This systematic review aimed to investigate the efficacy of laser photobiomodulation (PBM) on the acceleration of orthodontic tooth movement (OTM).

REVIEW METHODS

The study protocol was registered at PROSPERO (CRD42019121465). An extensive electronic search for randomized control trials and clinical control trials via Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Scopus up to date 24/02/2019 was done. Hand searching was performed for relevant journals. Reference articles were retrieved and exported to Mendeley Desktop 1.13.3 software. The risk of bias was assessed using the Cochrane risk of the bias assessment tool. Articles were further analyzed using Revman5.3 software.

RESULTS

A total of 14 articles were considered for systematic review and 9 articles were considered for meta-analysis. The results of the meta-analysis showed a significant difference between the laser group and conventional orthodontic treatment with Forest plots showing more tooth movement in the laser group compared to the control group in 2-3 months (mean difference = 1.73; CI: 0.9-2.57; p = 0.00001; I 2 = 89 %).

CONCLUSION

Although the analysis of the results shows that laser PBM favors OTM, the results are inconclusive as the heterogeneity across studies was high.

CLINICAL SIGNIFICANCE

Laser PBM may be considered as novel, safe, and noninvasive adjuvant therapy for the acceleration of OTM in children.

HOW TO CITE THIS ARTICLE

Yavagal CM, Matondkar SP, Yavagal PC. Efficacy of Laser Photobiomodulation in Accelerating Orthodontic Tooth Movement in Children: A Systematic Review with Meta-analysis. Int J Clin Pediatr Dent 2021;14(S-1):S94-S100.

Effect of Photobiomodulation on Relapse in an Experimental Rapid Maxillary Expansion Model in Rat

Rapid maxillary expansion (RME) is performed on transversely deficient maxilla. As all orthodontic treatments, retention is important in maintaining therapeutic outcomes. Fixed /removable retainers are used post-RME causing hygiene and compliance problems. Given photobiomodulation's positive effects on the quantity and quality of bone regeneration, its effect on post-RME relapse was studied. Thirty Sprague Dawley rats were randomly divided into group R, non-irradiated RME-treated (n = 12), group P, irradiated RME-treated (n = 12) and group C, non-RME non-irradiated (n = 6). A 1.5 mm metal ring inserted between maxillary incisors at days 0 and 15 was expanded until 1.5 mm space was obtained at day 30. In group P, Ga-Al-As diode laser (810 nm, 100 mW, 4J/cm² , 30 secs) was applied on days 0, 2, 4, 6, 8, 10, 12 and 14 as predictor variable. The relapse was measured as the space lost between incisors for 30 days after appliance removal (primary outcome variable) and compared with t-test. In week 2, space loss in group P was significantly lower (P < 0.05) than all other groups. The relapse during weeks 2 and 3 was significantly lower in group P than group R. However, no significant difference in relapse amount was found between groups during first and fourth week. There was a significant difference (P < 0.05) between groups in relapse rates (secondary outcome variable) but not in total relapse after 4 weeks. Photobiomodulation proved beneficial in resisting relapse in our study, and it is suggested to be continued until the end of expansion.

Efficacy of Flat-Top Hand-Piece Using 980 nm Diode Laser Photobiomodulation on Socket Healing after Extraction: Split-Mouth Experimental Model in Dogs

The objective was to evaluate the effect of photobiomodulation (PBM) using 980 nm diode laser therapy (0.60 W, 0.77 W cm^-2 , 36 J, 46 J cm^-2 , 60 s) irradiated in continuous wave mode by flat-top hand-piece on socket healing in the maxilla and mandible. A split-mouth experimental design was performed on 6 dogs. The 3^rd premolar tooth was extracted from the maxilla and mandibles for both sides. The right-sided sockets were irradiated (PBM group), and the left-sided sockets were kept as control. Irradiation was done after extraction and at 48-h interval for 14 days. Both the buccal and lingual sides were irradiated to reach a total irradiation time of 120 s. Bone density was evaluated at 3, 4 and 5 weeks using cone beam computed tomography. We showed that maxillary sockets in the PBM group had higher bone density compared to control one at 3, 4, 5 weeks (P = 0.029, <0.001, <0.001), respectively. Mandibular sockets revealed no significant difference between PBM and control at 3 weeks (P = 0.347), while at 4 and 5 weeks PBM group showed higher bone density (P = 0.004, <0.001). In both groups, there was a significant increase (P < 0.001) in bone density by time which was higher in the PBM group. We concluded that PBM using a flat-top hand-piece of 980-nm improved the bone density of extraction sockets.

Systematic reviews in orthodontics: Impact of the PRISMA for Abstracts checklist on completeness of reporting

INTRODUCTION

This study evaluated and compared the completeness of reporting of abstracts of orthodontics systematic reviews before and after the publication of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Abstracts Checklist (PRISMA-A).

METHODS

Abstracts of systematic reviews and meta-analyses in orthodontics published in PubMed, Latin American and Caribbean Health Sciences Literature, and the Cochrane Database of Systematic Reviews databases before March 23, 2018, that met the predefined inclusion and exclusion criteria, were evaluated using the 12 items of PRISMA-A, scoring each item from 0 to 2. Abstracts were classified into 2 groups: before and after publication of the PRISMA-A checklist. Three calibrated evaluators (intraclass correlation coefficient and kappa > 0.8) assessed the scores for compliance with the checklist. The number of authors, country of affiliation of the first author, performance of meta-analysis, and topic of the article were recorded. A regression analysis was performed to assess the associations between abstract characteristics and the PRISMA-A scores.

RESULTS

Of 1034 abstracts evaluated, 389 were included in the analysis. The mean PRISMA-A score was 53.39 (95% CI, 51.83-54.96). The overall score for studies published after the publication of the checklist was significantly higher than for studies published before (P ≤ 0.0001). The components returning significantly higher scores after publication of PRISMA-A were title (P = 0.024), information from databases (P = 0.026), risk of bias (P ≤ 0.0001), included studies (P ≤ 0.0001), synthesis of results (P ≤ 0.0001), interpretation of results (P = 0.035), financing and conflict of interest (P ≤ 0.0001), and registration (P ≤ 0.0001). These results showed the positive effect of PRISMA-A had on the quality of reporting of orthodontics systematic reviews. Nevertheless, the poor adherence revealed that there is still need for improvement in the quality of abstract reporting.

CONCLUSIONS

The quality of reporting of abstracts of orthodontic systematic reviews and meta-analyses increased after the introduction of PRISMA-A.

Effects of Different Parameters of Diode Laser on Acceleration of Orthodontic Tooth Movement and Its Effect on Relapse: An Experimental Animal Study

AIM

Recent studies have demonstrated that low-level laser therapy (LLLT) can accelerate orthodontic tooth movement. However, there is still controversy about the optimum parameters that can cause acceleration. The present study was designed to examine two different doses of LLLT in the acceleration of orthodontic tooth movement and their effect on relapse.

METHODS

An orthodontic appliance was designed to induce tooth movement on lower incisors of rabbits. The in-al-as diode laser was used to radiate different groups of rabbits according to a specific protocol. The amount of tooth movement was measured for 21 days, and then the orthodontic appliance was removed, and the relapse was measured till day 28.

RESULTS

The amount of tooth movement was significantly greater in the group with irradiation of low dose in comparison with the high dose group and the control group. The relapse was greatest in the group of low dose irradiation and least in the control group.

CONCLUSION

The findings suggest that LLLT with a low dose accelerate the orthodontic tooth movement while LLLT with a high dose was not able to have the same effect. LLLT had a reverse effect on relapse tendency; an increase in the relapse tendency was seen with low dose irradiation.

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.

Effect of Low-level Laser Therapy on Orthodontic Movement of Human Canine: a Systematic Review and Meta-analysis of Randomized Clinical Trials

Background:

Low-level Laser Therapy (LLLT) is a noninvasive method of accelerating tooth movement. Herein, this meta-analysis was aimed to assess the efficacy of LLLT in accelerating orthodontic tooth movement of human maxilla or mandible canine.

Methods:

Five databases including Web of Science, Scopus, PubMed, ScienceDirect, and Cochrane Library were used for searching the studies. Studies on LLLT for orthodontic tooth movement of human canine, randomized clinical trial (RCT), and outcome variables such as distance or speed of the tooth movement in treatment duration were considered for the final analysis. RevMan 5.3 was used for calculating the mean difference (MD) and 95% confidence intervals (CIs) on random-effects model.

Results:

Out of 275 studies retrieved from five databases, six RCTs were included and analyzed in this meta-analysis. The results showed that the orthodontic movement of canine was statistically increased in the LLLT group compared with the control group in 21 days (MD: 0.74; 95%CI: 0.17, 1.31; P = 0.01), one month (MD: 0.40; 95%CI: 0.10, 0.69; P = 0.008), 1.5 months (MD: 0.72; 95%CI: 0.51, 0.93; P < 00001), two months (MD: 0.84; 95%CI: 0.23, 1.44; P = 0.006) three months (MD: 0.92; 95%CI: 0.06, 1.78; P = 0.04), and 4.5 months (MD: 1.53; 95%CI: 0.92, 2.14; P < 0.00001).

Conclusion:

The LLLT can speed up the rate of tooth movement of human canine and consequently decrease the treatment time. LLLT represents a proper adjuvant therapy for fixed orthodontic treatment.

Effect of high-frequency near-infrared diode laser irradiation on periodontal tissues during experimental tooth movement in rats

BACKGROUND AND OBJECTIVES

Tooth movement during orthodontic treatment is associated with bone neoplasticity and bone resorption on the tension and pressure sides. Previous clinical studies have suggested that low-power laser irradiation can accelerate tooth movement during orthodontic treatment, although the underlying mechanism remains unclear. In this study, we used a high-frequency near-infrared diode laser that generates less heat and examined the histologic changes in periodontal tissue during experimental tooth movement with laser irradiation.

METHODS

A nickel-titanium closed coil was mounted between the maxillary left side first molar and incisor of rats to model experimental tooth movement. The laser-irradiation and the control groups were set, and the amount of movement of the first molar on 7th and 14th days after the start of pulling of the first molar tooth on the maxillary left was measured by three-dimensional analysis of µCT. After tooth movement, tissue samples from the mesial and tension sides were collected, and successive horizontal sections were prepared and examined using hematoxylin-eosin and TRAP staining and immunohistochemical staining for RANKL, OPG, ALP, and proliferating cell nuclear antigen (PCNA). Changes in tissue temperature following laser irradiation were also examined.

RESULTS

Laser irradiation significantly increased tooth movement compared with non-irradiated controls. Histologic staining of the pressure-side mesial root in laser-irradiated rats revealed enhanced RANKL expression and increased numbers of TRAP-positive cells compared with controls. By contrast, on the tension side, laser irradiation led to increased expression of ALP and PCNA. These data indicate that high-frequency near-infrared diode laser irradiation on the pressure side upregulates RANKL expression and accelerates osteoclast differentiation, facilitating bone resorption, whereas bone formation is induced on the tension side.

CONCLUSION

This study demonstrates that high-frequency near-infrared diode laser irradiation of periodontal tissue leads to metabolic activation, which ultimately increases the rate of tooth movement. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc.

Effect of Laser Photobiomodulation with Gradual or Constant Doses in the Regeneration of Rats' Mental Nerve After Lesion by Compression

OBJECTIVE

Assess morphologically the efficacy of constant dose (CD) or gradual dose (GD) in photobiomodulation therapy (PBMT) during the regeneration process of rats' mental nerve after compression lesion.

MATERIALS AND METHODS

Forty-eight male Wistar rats were used and divided into four groups (n = 12): negative control (NC): lesion by compression; positive control (PC): no lesion; GD: lesion by compression and PBMT with GD; and CD: lesion by compression and PBMT with CD. One day after the surgery, the groups GD and CD underwent PBMT daily in three equidistant points around the incision area. The parameters were wavelength of 808 nm, 100 mW, CD received treatment with 120 J/cm², while GD underwent the protocol of application: 1st and 4th sessions: 80 J/cm²; 5th to 8th sessions: 90 J/cm²; 9th to 12th sessions: 100 J/cm²; 13th to 16th sessions: 110 J/cm²; and 17th to 20th sessions: 120 J/cm². Euthanasias were performed at 3, 7, 14, and 21 days. Qualitative and quantitative analysis of the mental nerves were performed with ANOVA (analysis of variance) and Tukey tests (p ≤ 0.05).

RESULTS

It was observed that PBMT was able to accelerate the process of nerve regeneration presenting an increase in the number of myelinated fibers starting at 14 days of treatment for groups CD and GD, and at 21 days they were similar to PC. It was observed a better lamellar organization of myelin sheath at 7 days for GD and at 14 days for CD, similar to PC. Both GD and CD presented significant differences compared to NC and PC for thickness of the myelin sheath, outer perimeter, internal area, and number of myelin fibers.

CONCLUSIONS

PBMT presented positive effect on the regeneration of nerve starting at 14 days, and after 21 days there was no difference between GD and CD.

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.

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.

Are the mitochondrial respiratory complexes blocked by NO the targets for the laser and LED therapy?

Effects of laser (442 and 532 nm) and light-emitting diode (LED) (650 nm) radiation on mitochondrial respiration and mitochondrial electron transport rate (complexes II-III and IV) in the presence of nitric oxide (NO) were investigated. It was found that nitric oxide (300 nM-10 μM) suppresses mitochondrial respiration. Laser irradiation of mitochondria (442 nm, 3 J cm(-2)) partly restored mitochondrial respiration (approximately by 70 %). Irradiation with green laser (532 nm) or red LED (650 nm) in the same dose had no reliable effect. Evaluation of mitochondrial electron transport rate in complexes II-III and IV and effects of nitric oxide demonstrated almost similar sensitivity of complex II-III and IV to NO, with approximately 50 % inhibition at NO concentration of 3 μM. Subsequent laser or LED irradiation (3 J cm(-2)) showed partial recovery of electron transport only in complex IV and only under irradiation with blue light (442 nm). Our results support the hypothesis of the crucial role of cytochrome c oxidase (complex IV) in photoreactivation of mitochondrial respiration suppressed by NO.