Low-energy laser stimulates tooth movement velocity via expression of RANK and RANKL

Effects of coenzyme Q10 on orthodontic tooth movement and alveolar bone remodeling in rats

OBJECTIVES

To evaluate the effects of coenzyme Q10 (CoQ10) on alveolar bone remodeling and orthodontic tooth movement (OTM).

MATERIALS AND METHODS

An orthodontic appliance was placed in 42 female Sprague‒Dawley rats were divided into two groups: the orthodontic force (OF) group (n = 21) and the OF + CoQ10 (CoQ10) treatment group (n = 21). Each group was divided into 3 subgroups, and the rats were sacrificed on days 3, 7 and 14. The rats in CoQ10 and OF groups were administered 100 mg/kg b.w./day CoQ10 (in 1 mL/b.w. soybean oil) and 1 mL b.w./day soybean oil, respectively, by orogastric gavage. The OTM was measured at the end of the experiment. The osteoclast, osteoblast and capillary numbers; vascular endothelial growth factor (VEGF), receptor activator nuclear kappa B ligand (RANKL) and osteoprotegrin (OPG) levels in tissue; and total antioxidant status (TAS) and total oxidant status (TOS) in blood were determined.

RESULTS

Compared with the OF group, the CoQ10 treatment group exhibited decreased orthodontic tooth movement and osteoclast and capillary numbers. Indeed, the levels of VEGF and RANKL decreased, while the levels of OPG increased except on day 7. Additionally, the CoQ10 treatment group exhibited lower TOS and higher TAS on days 7 and 14 (p < 0.05). Histological findings showed that the morphology of osteoblasts changed in the CoQ10 group; however, there was no significant difference in the number of osteoblasts between the groups (p > 0.05).

CONCLUSION

Due to its effect on oxidative stress and inflammation, CoQ10 regulates bone remodeling by inhibiting osteoclast differentiation, promoting osteoblast differentiation and reducing the amount of OTM.

CLINICAL RELEVANCE

Considering that OTM may be slowed with the use of CoQ10, topics such as orthodontic treatment duration, orthodontic force activation and appointment frequency should be considered in treatment planning. It is predicted that the use of CoQ10 will support the effectiveness of treatment in clinical applications such as preventing relapse in orthodontic treatment by regulating bone modulation and anchorage methods that suppress/optimize unwanted tooth movement.

Effect of low-level laser therapy on en masse retraction in females with bimaxillary dentoalveolar protrusion : A single-center randomized clinical trial

BACKGROUND

Acceleration of tooth movement has gained remarkable attention during the last decade. The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on en masse retraction of upper anterior teeth in adult women with bimaxillary dentoalveolar protrusion.

MATERIALS AND METHODS

In this two-arm parallel trial, 36 women with bimaxillary dentoalveolar protrusion were randomly divided into two equal groups. Eligibility criteria included class I Angle molar relationship, good general and oral health as well as no systemic disease or syndrome. Four temporary anchorage devices (TADs) were used in the upper and lower arches for anchorage purposes. A 0.019×0.025-inch stainless steel wire with crimped hooks just distal to the maxillary canines was inserted. Nickle titanium (NiTi) closed coil springs (200 g/side) were employed for en masse retraction following extraction of the first premolars. In the laser group (LG), retraction of the upper anterior teeth was done along with the application of LLLT on days 0, 3, 7, and 14 after extraction and then repeated biweekly until the end of retraction. Retraction was completed without LLLT application in the nonlaser group (NLG). Data concerning the rate of retraction as well as first molars and anterior positional changes were gained from digitized models and cone beam computed tomography (CBCT) scans taken just before extraction and at the end of retraction. Treatment-associated pain and root resorption were evaluated using visual analogue scale (VAS) and CBCT scans, respectively.

RESULTS

Four patients dropped out prior to follow-up. The duration of retraction was 10.125 ± 2.876 and 13.643 ± 3.455 months in the LG and NLG, respectively. The LG showed a statistically significant faster rate of en masse retraction (0.833 ± 0.371 mm/month) compared to the NLG (0.526 ± 0.268 mm/month; P ≤ 0.035). The observed root resorption was significantly less in the LG (P ≤ 0.05) with comparable pain scores in both groups.

CONCLUSIONS

Within the constraints of the parameters of the LLLT used in the current study and despite the statistically significant results on the rate of en masse retraction and the associated root resorption, LLLT did not demonstrate a clinically relevant effect that justifies its use to enhance en masse retraction.

NAME OF THE REGISTRY

Clinicaltrials.gov TRIAL REGISTRATION NUMBER: NCT05183451 DATE OF REGISTRATION: January 10, 2022, "Retrospectively registered" URL OF TRIAL REGISTRY RECORD: https://www.

CLINICALTRIALS

gov/study/NCT05183451.

Photobiomodulation in Orthodontics: Mechanisms and Clinical Efficacy for Faster Tooth Movement

Accelerated orthodontics has revolutionized traditional dental practices by employing innovative techniques to expedite tooth movement and enhance treatment outcomes. Among these advancements, low-level laser therapy (LLLT) has emerged as a promising adjunctive method that offers a non-invasive and efficient approach to accelerate orthodontic tooth movement. By harnessing the power of low-level lasers, LLLT aims to stimulate cellular activity, promote bone remodeling, and reduce treatment duration, thereby revolutionizing the landscape of orthodontic care. In this review, we discuss the mechanism of action, methods, efficacy, advantages, limitations, and future scope of LLLT, uncovering its transformative impact on the field of accelerated orthodontics.

Ameliorating orthodontic relapse using laser bio-stimulation and mesenchymal stem cells in rats

BACKGROUND

Orthodontic relapse is a frequent problem that many patients experience. Although orthodontic therapy has advanced, recurrence rates can still reach 90%. We undertook a study to look at the possibilities of laser bio-stimulation and stem cells because they have showed promising outcomes in lowering recurrence rates.

OBJECTIVES

Our objective was to analyze the effects of Low-level laser therapy (LLLT) and Mesenchymal stem cells (MSC) alone and collectively on the rate of orthodontic relapse in rats radiographically and histologically.

METHODS

Rat maxillary central incisors were moved distally for two weeks. One week later, the incisors were retained. Animals (n = 40) were split into four groups. Control group (C); laser treatment Group (L), Bone marrow mesenchymal stem cells Group (BMSCs) and combination of Stem cells and laser-irradiation group (BMSCs-L). Removed retainer permitted relapse. Before stem cell application or laser irradiation, each animal underwent two CBCT scans. Rat maxillae were stained with Hx&E, Masson trichrome, and tartrate-resistant acid phosphatase antibody for histology, histochemistry, and immunohistochemistry.

RESULTS AND CONCLUSIONS

LLLT could reduce the relapse tendency, as shown by increased bone density and enhanced remodeling of hetero-formed periodontal ligament (PDL). Furthermore, the transfer of BMMSCs on the pressure side had positive effects on PDL remodeling and decreased, but did not inhibit, the relapse rate. Finally, the synergistic effects of the application of LLLT and BMMSC were better than the control but still moderate and long-lasting.

CLINICAL SIGNIFICANCE

Based on the improved relapse rate as proven in the present study, the Application of both LLLT and stem cells can be adopted to reduce the relapse tendency either lonely or collectively.

Influence of Ultrasound Stimulation on the Viability, Proliferation and Protein Expression of Osteoblasts and Periodontal Ligament Fibroblasts

Among the adjunctive procedures to accelerate orthodontic tooth movement (OTM), ultrasound (US) is a nonsurgical form of mechanical stimulus that has been explored as an alternative to the currently available treatments. This study aimed to clarify the role of US in OTM by exploring different stimulation parameters and their effects on the biological responses of cells involved in OTM. Human fetal osteoblasts and periodontal ligament fibroblasts cell lines were stimulated with US at 1.0 and 1.5 MHz central frequencies and power densities of 30 and 60 mW/cm2 in continuous mode for 5 and 10 min. Cellular proliferation, metabolic activity and protein expression were analyzed. The US parameters that significantly improved the metabolic activity were 1.0 MHz at 30 mW/cm2 for 5 min and 1.0 MHz at 60 mW/cm2 for 5 and 10 min for osteoblasts; and 1.0 MHz at 30 mW/cm2 for 5 min and 1.5 MHz at 60 mW/cm2 for 5 and 10 min for fibroblasts. By stimulating with these parameters, the expression of alkaline phosphatase was maintained, while osteoprotegerin synthesis was induced after three days of US stimulation. The US stimulation improved the biological activity of both osteoblasts and periodontal ligament fibroblasts, inducing their osteogenic differentiation.

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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Impact of Low-Level Laser Therapy on Orthodontic Tooth Movement and Various Cytokines in Gingival Crevicular Fluid: A Split-Mouth Randomized Study

BACKGROUND AND OBJECTIVES

A few investigations have detailed the influence of low-level laser therapy (LLLT) on orthodontic tooth movement (OTM), with varying results. The objectives of this study were twofold: to assess the impact of LLLT on OTM and various cytokine levels in gingival crevicular fluid and to contrast the pain levels experienced by patients receiving orthodontic treatment with and without LLLT.

MATERIALS AND METHODS

This split-mouth randomized controlled prospective study comprised 40 patients with an average age of 19.7±2.4 years with Angle Class I malocclusion combined with bimaxillary protrusion who were advised for extraction of the maxillary first premolar and bilateral canine distalization. The control-side canine was distalized solely by the coil spring. On the test arm, a low-level gallium-aluminum-arsenide semiconductor diode laser operating at 980 nm and 100 mW with a continuous-wave energy of 8 J/cm2 was used. The canine distalization on either side was measured with a digital caliper following the first premolar extraction (TO), one month after treatment (TOTM1), two months later (TOTM2), and three months later (TOTM3). The gingival index and the level of various cytokines were determined by an enzyme-linked immunosorbent assay at the beginning of the study, on the third and seventh days, and at four, eight, and 12 weeks following the canine distalization. The intra-group and inter-group comparisons were carried out using one-way analysis of variance (ANOVA) and t-tests, respectively, at a 5% significance level.

RESULTS

The results show a highly statistically significant difference in the extent of canine distalization in the test group (TOTM1=2.92±0.44; TOTM2=1.04±0.1; TOTM3​=0.62±0.21 mm) in contrast to the control group (TOTM1=3.23±0.8; TOTM2=2.65±0.2; TOTM3​​​​=2.11±0.24 mm) (p<0.01). After three months of canine distalization, the laser and control group had 34 and 27 patients with mild gingivitis, respectively. Interleukin-1β and interleukin-6 concentrations surged with values of 0.74±0.13 and 0.049±0.001 pg/g at seven days following treatment in the laser group, respectively. The difference in tumor necrosis factor concentration between the groups was shown to be highly statistically significant in all treatment phases (p<0.001). The differences in the epidermal growth factor and microglobulin levels were found to be statistically significant within both groups from T0 to T5. The average visual analog scale (VAS) scores at several subsequent evaluations of the laser and control groups were found to be highly statistically significant.

CONCLUSION

The findings imply that when the periodontal microenvironment is stimulated by orthodontic force, several paramount cytokines are released, triggering an ordered sequence of biological processes that appear to expedite OTM with reduced associated pain.

The Effects and Mechanisms of PBM Therapy in Accelerating Orthodontic Tooth Movement

Malocclusion is one of the three major diseases, the incidence of which could reach 56% of the imperiled oral and systemic health in the world today. Orthodontics is still the primary method to solve the problem. However, it is clear that many orthodontic complications are associated with courses of long-term therapy. Photobiomodulation (PBM) therapy could be used as a popular way to shorten the course of orthodontic treatment by nearly 26% to 40%. In this review, the efficacy in cells and animals, mechanisms, relevant cytokines and signaling, clinical trials and applications, and the future developments of PBM therapy in orthodontics were evaluated to demonstrate its validity. Simultaneously, based on orthodontic mechanisms and present findings, the mechanisms of acceleration of orthodontic tooth movement (OTM) caused by PBM therapy were explored in relation to four aspects, including blood vessels, inflammatory response, collagen and fibers, and mineralized tissues. Also, the cooperative effects and clinical translation of PBM therapy in orthodontics have been explored in a growing numbers of studies. Up to now, PBM therapy has been gaining popularity for its non-invasive nature, easy operation, and painless procedures. However, the validity and exact mechanism of PBM therapy as an adjuvant treatment in orthodontics have not been fully elucidated. Therefore, this review summarizes the efficacy of PBM therapy on the acceleration of OTM comprehensively from various aspects and was designed to provide an evidence-based platform for the research and development of light-related orthodontic tooth movement acceleration devices.

Biomodulation of Induced Tooth Movement by Three Methods, Corticopuncture, Photobiomodulation, and Their Combination: An Animal Study

Objective: The aim of this study was to assess the effects of accelerated tooth movement (ATM) methods: corticopuncture (CP), photobiomodulation (PBM), and their combination (CP + PBM) by evaluating tooth displacement, alveolar bone changes, and molecular and cellular response compared with conventional induced tooth movement. Materials and methods: Tooth movement and bone changes were evaluated on days 1, 3, and 7 (9 animals per time point) using microtomography, histological, and immunohistochemical evaluation, at compression and tension sites. CP groups received two perforations in the palate and one mesial to the molars. PBM was performed using GaAlAs diode laser applied every other day for 7 days (λ = 808 nm, 100 mW) in two points for 15 sec/point and total energy of 3 J. Results: Tooth movement was significantly increased in all three ATM groups after 7 days compared with the control group (mean 0.24 mm) by 27% PBM (0.31 mm), 45% CP (0.35 mm), and 57% CP + PBM (0.38 mm) (p < 0.05). At the compression side, all ATM groups showed significant decrease in bone density on day 3 (p < 0.05) and significant less bone volume on day 7 compared with Control (p < 0.05). At the tension side, PBM group showed a significant increase in bone density and volume on day 3 (p < 0.05). Immunohistochemistry analysis showed that at the compression side, tartrate-resistant acid phosphatase-positive cells, RANKL, and tumor necrosis factor-alpha expression were highly marked of the PBM and the combined method groups (p < 0.05). PBM and CP + PBM groups showed a significant increase in expression Runt-related transcription factor 2 and osterix (p < 0.05) at the tension side. Conclusions: All ATM groups showed increase on tooth displacement with CP + PBM group showing greatest tooth displacement. CP method appears to stimulate bone catabolism, PBM has more effect on bone formation, and the combined method showing a synergistic effect on bone remodeling.

Research Advances on Stem Cell-Derived Extracellular Vesicles Promoting the Reconstruction of Alveolar Bone through RANKL/RANK/OPG Pathway

Periodontal bone tissue defects and bone shortages are the most familiar and troublesome clinical problems in the oral cavity. Stem cell-derived extracellular vesicles (SC-EVs) have biological properties similar to their sources, and they could be a promising acellular therapy to assist with periodontal osteogenesis. In the course of alveolar bone remodeling, the RANKL/RANK/OPG signaling pathway is an important pathway involved in bone metabolism. This article summarizes the experimental studies of SC-EVs applied for the therapy of periodontal osteogenesis recently and explores the role of the RANKL/RANK/OPG pathway in their mechanism of action. Their unique patterns will open a new field of vision for people, and they will help to advance a possible future clinical treatment.

Effect of low-level laser therapy on orthodontic tooth movement during miniscrew-supported maxillary molar distalization in humans: a single-blind, randomized controlled clinical trial

To investigate the effect of low-level laser therapy (LLLT) on orthodontic tooth movement during maxillary molar distalization over a 12-week observation period. Twenty patients were enrolled in this clinical trial. On the 0th, 3rd, 7th, 14th, 21st, 42nd, and 63rd days following the initial activation of the distalization appliance, laser therapy was applied in a total of 16 different points of the first and second molars for 10 s per point to the randomly determined molar region of the individuals in the intervention group. The amount of molar distalization was measured using digital scans of the three-dimensional (3D) digital models obtained during the 3rd, 6th, 9th, and 12th weeks. The amount of tooth movement on the laser-applied side of subjects in the intervention group was significantly greater than those in the contralateral and control groups at all time intervals (p < 0.001). The amount of tooth movement between the contralateral side of the intervention group and the control group was determined to be statistically insignificant (p > 0.05) at all time intervals. The laser-treated molars of the subjects in the intervention group moved 1.22 times more than the molars in the contralateral side and in the control group in 12 weeks. The rate of tooth movement in the laser, contralateral, and control groups was 0.033, 0.027, and 0.027 mm/day, respectively. Although LLLT was found to be statistically significant in terms of accelerating tooth movement, the effect of LLLT is not considered to be clinically significant. This trial was retrospectively registered (September 22, 2022) at Clinical-Trials.gov (Ref no: NCT05550168).

Accelerated Canine Retraction by Using Mini Implant With Low-Intensity Laser Therapy

Background The continuous increase in demand for reduced treatment times has led researchers to think in terms of "accelerated orthodontics." Generally, the duration for fixed orthodontic treatment is around two to three years. Prolonged use of braces leads to external root resorption, a high risk of caries, and decreased patient compliance. Therefore, finding an optimal supplementary approach to achieve faster tooth movement is still considered a subject of interest. Low-intensity laser therapy (LILT) is one of the non-invasive surgical techniques in the field of accelerated orthodontics. Low-level laser therapy (LLLT) has demonstrated faster healing, less bleeding, and biostimulation and anti-inflammatory effects. According to all studies, it accelerates tooth movement, thereby reducing braces treatment time. It is simple, safe, and minimally invasive. Despite these pieces of evidence, studies have shown variable findings in low-level laser therapy. This study evaluates the effect of LLLT on accelerated orthodontics in comparison with conventional canine retraction. An aluminum gallium arsenide-type diode laser with a wavelength of 940 nm has been used in this study. Methodology This study was conducted using the split-mouth method, which included 20 patients with permanent dentition who required first premolar extractions. A miniscrew implant was placed on both the right and left sides for maximum anchorage. Irradiation doses were applied on days 0, 3, 7, and 14 of the first month. Subsequently, irradiations were given every 15 days until the canine's retraction was complete in the test group. Results The study results three months after the canine retraction in the test and control groups (M1) were 0.81 ± 0.03 mm/month and 0.74 ± 0.04 mm/month, respectively, indicating a significantly higher rate of canine retraction in the test group than in the control group (P < 0.0001). The average increase in the amount of tooth movement at three months was 40.1% and 36.3% in the test and control groups, respectively. However, the average increase in the amount of movement of teeth following canine retraction was 100% in the test group and 68.2% in the control group. There were significant variations in the pain score between Day 1 and Day 3 (P = 0.003) in the test group; however, there was no analytic variation in the pain score between Day 1 and Day 30 in the test group (P = 0.18). The pain score between Day 3 and Day 30 was significantly lower. Conclusions It was concluded that the rate of canine retraction increases when it is combined with LILT-assisted accelerated orthodontics in comparison to conventional canine retraction. Although LLLT does not provide immediate pain relief, it relieves the sensation of pain after 24-72 hours. LILT is an innovative, non-invasive technique that allows rapid orthodontic tooth movement. The rate of canine retraction increases when it is combined with LILT-assisted accelerated orthodontics in comparison to conventional canine retraction using mini-implants.

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

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

Effect of humic acid as a photosensitizer combined with low-energy laser on orthodontic tooth movement in rats

Background/purpose

Humic acid (HA) could promote light conversion reaction, and lasers accelerate orthodontic tooth movement. We investigated the effect of HA, as a photosensitizer, combined with low-energy laser on orthodontic tooth movement in rats.

Materials and methods

An orthodontic tooth movement model was established, and the upper left first molar was moved mesially by a nickel-titanium tension spring with a 50-g force. HA was injected into the rats’ abdominal cavity (80 mg/kg once daily). The periodontal tissue of the upper left upper first molar on the pressure side was irradiated (50 s once every 2 days) using a semiconductor laser (wavelength, 650 nm; power, 50 mV). Distance moved by the upper left first molar was measured at different time points, and the tissue of the first molar was sectioned and scanned by micro-computed tomography to evaluate the alveolar bone density. Tartrate-resistant acidic phosphatase staining was used to observe the osteoclast number, alveolar bone, and periodontal tissue.

Results

HA alone did not significantly affect orthodontic tooth movement, alveolar structure density, or periodontal tissue remodeling (P > 0.05). HA combined with a low-energy laser accelerated orthodontic tooth movement. The number of bone absorption lacunae and osteoclasts on the alveolar bone's pressure side increased significantly (P < 0.05), while the density decreased significantly (P < 0.05); however, no root absorption was observed.

Conclusion

HA can improve the conversion rate of low-energy lasers, enhance the low-energy laser effect, and promote orthodontic tooth movement and periodontal tissue reconstruction on the pressure side in rats, without causing root resorption.

Magnetism in Dentistry: Review and Future Perspectives

Tissue engineering or tissue reconstruction/repair/regeneration may be considered as a guiding strategy in oral and maxillofacial surgery, as well as in endodontics, orthodontics, periodontics, and daily clinical practice. A wide range of techniques has been developed over the past years, from tissue grafts to the more recent and innovative regenerative procedures. Continuous research in the field of natural and artificial materials and biomaterials, as well as in advanced scaffold design strategies has been carried out. The focus has also been on various growth factors involved in dental tissue repair or reconstruction. Benefiting from the recent literature, this review paper illustrates current innovative strategies and technological approaches in oral and maxillofacial tissue engineering, trying to offer some information regarding the available scientific data and practical applications. After introducing tissue engineering aspects, an overview on additive manufacturing technologies will be provided, with a focus on the applications of superparamagnetic iron oxide nanoparticles in the biomedical field. The potential applications of magnetic fields and magnetic devices on the acceleration of orthodontic tooth movement will be analysed.

Effect of 970 nm low-level laser therapy on orthodontic tooth movement during Class II intermaxillary elastics treatment: a RCT

This prospective randomized clinical trial aimed to evaluate the effect of low-level laser therapy on tooth movement during Class II intermaxillary elastics treatment. Forty-two patients with Class II malocclusion were included, and their maxillary quadrants were allocated into two groups: treatment with an active diode laser and a placebo group. In each group, the time taken to obtain Class I occlusion after 6 months, rate of movement, total displacement of the maxillary canine to Class I occlusion and pain were recorded. The time to reach Class I occlusion in the active laser group (2.46 ± 2.1 months) was not significantly different from that in the placebo group (2.48 ± 2.0 months) (p = 0.938). Interestingly, the total distance of movement on the active laser side (2.27 ± 1.5 mm) was significantly greater than that on the placebo side (1.64 ± 1.3 mm) (p = 0.009). The pain levels on days 1, 2 and 3 were not significantly different between the laser and placebo sections. The rate of distance change toward Class I occlusion in the laser group (1.1 ± 0.7 mm/month) was significantly higher than that in the placebo group (0.74 ± 0.6 mm/month) (p = 0.037). Low-level laser therapy (970 nm) did not reduce the time needed to obtain Class I occlusion, but a significant acceleration in tooth movement was observed in the irradiated group.

Trial registration: NCT02181439. Registered 04 July 2014—https://www.clinicaltrials.gov/ct2/results?term=cinelaser.

EFFECTIVENESS OF VIBRATION (CYCLIC LOADING) IN ACCELERATING BONE REMODELING AND ORTHODONTIC TOOTH MOOVEMENT: A SHORT REVIEW

This paper assesses the effectiveness of vibration in accelerating bone remodeling and orthodontic tooth movement. Databases of PubMed, Web of Science, and ScienceDirect were searched from January 2017 to March 2019 for randomized or quasi-randomized controlled trials that evaluated the effectiveness of vibration in accelerating bone remodeling and orthodontic tooth movement. The inclusion criteria were as follows: (i) studies that assessed the efficacy of vibration (cyclic loading) in bone remodeling and orthodontic tooth movement and (ii) those that employed groupings (experimental vs. control/placebo groups) on the basis of the use of vibration (cyclic loading). Eight clinical trials were included in this short review. Five studies met the eligibility criteria for bone remodeling and orthodontic tooth movement. Four studies found that low-magnitude high-frequency vibration could accelerate bone remodeling. However, contradictory results were obtained with regard to the acceleration of orthodontic tooth movement by vibration in human participants. Low-magnitude high-frequency vibration can accelerate bone remodeling and orthodontic tooth movement. However, this acceleration is dependent on the magnitude and frequency. Further research is necessary to determine the most feasible protocols for investigating the effects of magnitude and frequency of vibration on the acceleration of orthodontic tooth movement in human participants.

Efficacy of micro-osteoperforation of the alveolar bone by using mini-screw for acceleration of maxillary canine retraction in young adult orthodontic patients: A split-mouth randomized clinical trial

AIM

Acceleration of orthodontic tooth movement (OTM) can decrease the rate of complications. This study aimed to assess the efficacy of micro-osteoperforation (MOP) of the alveolar bone for acceleration of OTM by using mini-screws.

MATERIALS AND METHODS

This split-mouth randomized clinical trial evaluated 25 patients (11 females, 14 males, 16-25 years) with class II division I malocclusion who required canine retraction following the extraction of maxillary first premolar. The patients received similar orthodontic treatment at both sides with MOP on one side (MOP group) and no MOP on the other side (control side). Allocation of MOP to the side of jaw was random using Random Allocation Software in 1:1 distribution and equal numbers. Blinding was not applicable. The rate of canine movement was measured monthly for 5 months and considered as the main outcome. The degree of canine tipping was measured at the end of the intervention as the secondary outcome. All measurements were repeated for 12 patients by the two observers and the intra- and inter-examiner correlation coefficients were found to be 0.946 and 0.925, respectively. Data were analysed by paired t-test and repeated measures ANOVA.

RESULTS

Twenty-five patients (11 females, 14 males, 16-25 years) were evaluated. No significant difference was found between the two groups at different time points in the rate of canine movement (P>0.05). The degree of canine tipping in the MOP group was significantly lower than that in the control group (5.34±3.11° versus 7.08±3.70°; P=0.040). Gender had no significant effect on OTM in any group (P>0.05).

CONCLUSIONS

MOP could not accelerate canine retraction but decreased the degree of canine tipping.

Uncovering and Autonomous Eruption of Palatally Impacted Canines-A Case Report

The impaction of permanent maxillary canine is a common clinical occurrence, and it is observed in 2% of patients who require orthodontic treatment. This case report describes a new orthodontic-surgical approach through the use of CO₂ laser, for the exposure of the palatally impacted canines. A 13-year-old female referred to our observation to make an orthodontic examination because of the maxillary primary canines’ persistence in upper arch. Orthopanoramic X-ray showed impaction of both permanent maxillary canines. The family history revealed that the patient’s mother had the same orthodontic problem. Cone Beam Computer Tomography (CBCT) was requested to plan the surgical-orthodontic treatment. Surgical exposure of the impacted canines was performed using a CO₂ laser and subsequent periodontal pack application. No orthodontic devices were applied for impacted teeth traction on dental arch. Canines’ movement was monitored at 1, 8 and 16 weeks post-surgery with photo and intraoral scanner CS3500 (CS3500^®, Carestream Health, Atlanta, GA, USA). When canine crowns were completely erupted on palatal side, the alignment in the arch with indirect bonding technique was performed. Complete disimpaction of canine crowns was obtained in only four months. As reported in the literature, this case confirms that impacted canines’ exposure to CO₂ laser has advantages if compared with traditional surgery: no bleeding during and after the procedure, decontaminant effect on the surgical area, no suture, and a fast spontaneous eruption. Conclusions: The pre-orthodontic uncovering and autonomous eruption of palatally impacted maxillary canines provides simplified, predictable, and more aesthetic outcomes. Furthermore, a significant positive factor is that there is no need to carry out the orthodontic traction of the impacted element, undoubtedly better compliance by the patient during the next alignment phase with the fix orthodontic appliance.

Photobiomodulation and Antiviral Photodynamic Therapy in COVID-19 Management

Coronavirus disease 2019 (COVID-19) has shocked the world by its spread and contagiousness. There is no approved vaccine and no proven treatment for this infection. Some potential treatments that have already been associated with antiviral and anti-inflammatory effects are under investigation. Photobiomodulation therapy (PBMT) is a photon-based therapy that uses light to mediate a variety of metabolic, analgesic, anti-inflammatory, and immunomodulatory effects. Antiviral photodynamic therapy (aPDT) is a branch of photodynamic therapy based on the reaction between a photosensitizing agent and a light source in the presence of oxygen, which can produce oxidative and free radical agents to damage the viral structures such as proteins and nucleic acids. This chapter aims to discuss the potential therapeutic benefit of PBMT and aPDT in the context of the novel coronavirus. Studies indicate that PBMT and aPDT could be useful in many viral and bacterial pulmonary complications like influenza, SARS-CoV, and MERS, but we found no direct study on SARS-CoV-2. With a combination of PBMT and aPDT, we may be able to combat COVID-19 with minimal interference with pharmaceutical agents. It might improve the efficacy of PBMT and aPDT by using monoclonal antibodies and preparing new photosensitizers at the nanoscale that target the lung tissue specifically. More animal and human studies would need to take place to reach an effective protocol. This chapter would encourage other scientists to work on this new platform.

Efficacy of Photobiomodulation Therapy for Orthodontic Pain Control Following the Placement of Elastomeric Separators: A Randomized Clinical Trial

Introduction: Controlling pain in orthodontic patients has gained special attention. This study assessed the efficacy of photobiomodulation therapy (PBMT) for pain control following the placement of elastomeric separators. Methods: This split-mouth single-blind randomized clinical trial evaluated 30 orthodontic patients who required posterior elastomeric separators. The two maxillary quadrants were randomized into the laser and control groups. In the laser quadrant, an 808 nm diode laser (400 mW, 15.60 J/cm² , 11 seconds, continuous-wave, contact mode) was irradiated to the cervical third of the maxillary first molar roots 24 hours prior to the placement of separators. The control quadrant received placebo radiation by a light-curing unit. The patients received the second laser cycle right before the placement of separators 24 hours later. The level of self-perceived pain was recorded at 0, 2, 6, 24, and 72 hours and 5 days after the intervention in the laser and control quadrants using a visual analog scale (VAS). Data were analyzed using the analysis of variance (ANOVA) and paired-samples t test. Results: The trend of change in the pain score was similar in both groups. The pain score was significantly lower in the laser group than the control group at all-time points (P <0.05) except at time 0. The pain score increased in the first 6 hours and reached its maximum level in 24 hours in both groups. Conclusion: PBMT by an 808 nm diode laser can effectively decrease pain following the placement of elastomeric separators.

Effect of photobiomodulation on external root resorption during orthodontic tooth movement - a randomized controlled trial

OBJECTIVE

The objective of the study was to compare external root resorption during orthodontic tooth movement between patients who were subjected to photobiomodulation and those who were not.

MATERIALS AND METHODS

The study was designed as a split-mouth, single-blind randomized controlled trial conducted on twenty-two orthodontic patients requiring extraction of maxillary first premolars (age group 13-30years). A buccal force was applied to all the premolars using a 0.019″×0.025″ beta-titanium cantilever spring for 28days. The test group premolars were irradiated by indium-gallium-arsenide (InGaAs) diode laser (980nm, 100mW) 0, 3, 7, 11, 15 and 28days after force application. Each premolar was irradiated at ten locations on the buccal and palatal gingiva resulting in a total energy of 10J delivered per tooth. After 28days, the root surface of all the premolars were studied for the number and volume of resorption craters using three-dimensional optical profilometry by a blinded assessor. One-sample Kolmogorov-Smirnov test was used to ascertain normality and Mann-Whitney U test was applied for data analysis.

RESULTS

All twenty-two patients enrolled completed the study. The root surface analysis showed formation of 32.78% less number of resorption craters (P<0.05) and 39.49% less volume of resorption craters (P<0.05) in the test group premolars relative to the control group premolars.

CONCLUSIONS

The results of the present study, therefore, suggest that photobiomodulation reduces external root resorption during orthodontic tooth movement.

TRIAL REGISTRATION/REGISTRATION NUMBER

CTRI/2018/04/013520.

Evaluation of the effects of diode laser application on experimental orthodontic tooth movements in rats. Histopathological analysis

Purpose:

To evaluate the effect of diode laser use on experimental orthodontic tooth movements.

Methods:

Thirty Rattus norvegicus albinus Wistar were divided into three equal groups (n = 10), two experimentals and one control. Applying 20 g orthodontic force were attached to the maxillary incisors of the rats in all groups. Low dose laser was applied to the surrounding tissues of the maxillary incisors of the rats in the experimental groups. Two exposure times for laser irradiation were used for seven days: t = 12 min (energy dose = 72 J) and t = 9 min (energy dose = 54 J) by a 0.1 W DEKA brand diode laser with wavelength of 980 nm.

Results:

Osteoclastic activation increased in the 72 J group when compared to control group and decreased in comparison to the 54 J group. Osteoblastic activation was decreased in the 72 J group when compared to the control group and increased in comparison to the 54 J group.

Conclusions:

Applying 54 J laser energy has been found effective to accelerate the orthodontic tooth movement.

Do adjunctive interventions in patients undergoing rapid maxillary expansion increase the treatment effectiveness?

OBJECTIVES

To evaluate the clinical effectiveness of adjunctive interventions in individuals undergoing rapid maxillary expansion (RME).

MATERIALS AND METHODS

MEDLINE, Web of Science, Cochrane, Scopus, LILACS, and Google Scholar were searched without restrictions up to June 2020. Trials involving participants undergoing orthopedic or surgical RME, along with adjunctive interventions, were included. Risk-of-bias assessments were performed using the Cochrane tool for randomized trials-2. The certainty level of evidence was assessed through the Grading of Recommendations Assessment, Development and Evaluation tool.

RESULTS

Six randomized clinical trials, with low to high risk of bias, were included. Low certainty of the evidence suggested that low-level laser facilitated opening of the midpalatal suture during the active phase of RME. Likewise, moderate certainty demonstrated that low-level laser accelerated the healing process of the suture during the retention phase. The clinical impact of this outcome, that is, stability and retention time, was not evaluated. Very low evidence indicated that osteoperforations along the midpalatal suture increased maxillary transverse skeletal gains in young adults undergoing RME. Low evidence suggested that platelet-rich plasma therapy did not minimize the vertical and thickness bone loss after RME in the short term.

CONCLUSIONS

Based on currently available information, the use of low-level laser associated with maxillary expansion seems to provide a more efficient suture opening and bone healing. Limited evidence suggests that osteoperforations improve the skeletal effects of RME in non-growing individuals. There are no adjunctive interventions capable of reducing the periodontal side effects of RME.

Effects of 405-, 532-, 650-, and 940-nm wavelengths of low-level laser therapies on orthodontic tooth movement in rats

Background

Investigating the effects of 405-nm, 532-nm, 650-nm, and 950-nm wavelengths of LLLTs (low-level laser therapies) on the orthodontic tooth movement in rats by using histological and immunohistochemical methods. Forty-five Wistar albino rats were randomly divided into 5 groups: control group (positive control: the left maxillary 1st molar side; negative control: the right maxillary 1st molar side), 405 nm LLLT group (Realpoo), 532 nm LLLT group (Realpoo), 650 nm LLLT group (Realpoo), and 940 nm LLLT group (Biolase). The left maxillary 1st molar teeth of all rats were applied mesially 50-g force. Starting from the 1st day, 48 h intervals, LLLT was applied in continuous wave mode and in contact with the tissue. The application area was approximately 1 cm². The lasers were performed for 3 min on each surface (buccal, palatal, mesial), totally 9 min (total dose 54 J/cm²). The amount of the molar mesialization, the bone area between the roots, PDL (periodontal ligament) measurements, TRAP (tartrate-resistant acid phosphatase), and ALP (alkaline phosphatase) immunoreactivity intensity were calculated.

Results

The amount of the molar mesialization was significantly higher in the 650 nm LLLT group (mean 0.878 ± 0.201 mm; 95% CI (confidence interval) 0.724 and 1.032) than in the groups of positive control (mean 0.467 ± 0.357 mm; 95% CI 0.192 and 0.741) and 405 nm LLLT (mean 0.644 ± 0.261 mm; 95% CI 0.443 and 0.845) (p < 0.001). There were significant differences in the PDL-mesial (p = 0.042) and PDL-distal (p = 0.007) regions between the groups. The immunoreactivity intensity for TRAP-mesial was significantly higher in the positive control group (mean 109,420.33 ± 8769.17; 95% CI 100,217.65 and 118,623.02) than in the 405 nm (mean 91,678.83 ± 7313.39; 95% CI 84,003.9 and 99,353.77) and the 650 nm LLLT (mean 87,169.17 ± 4934.65; 95% CI 81,990.56 and 92,347.77) groups (p = 0.002). There was no statistically significant difference between the groups on immunoreactivity intensity with ALP staining.

Conclusions

The results of this study show that LLLT with 650-nm wavelength increases orthodontic tooth movement more than 405-nm, 532-nm, and 940-nm LLLTs. The 940-nm and 650-nm LLLTs also increase the bone area between the roots by more than 405-nm and 532-nm wavelengths.

Comparison of rate of orthodontic tooth movement in adolescent patients undergoing treatment by first bicuspid extraction and en-mass retraction, associated with low level laser therapy in passive self-ligating and conventional brackets: A randomized controlled trial

BACKGROUND

Low Level Laser Therapy (LLLT) is one of the various interventions to accelerate the rate of Orthodontic Tooth Movement (OTM) in adolescent patients who are undergoing en-mass retraction after all first bicuspid extractions.

OBJECTIVES

To assess the efficacy of LLLT in increasing the rate of OTM.

MATERIALS AND METHODS

Setting and sample population: Institutional Department of Orthodontics and Dentofacial Orthopaedics. Participants, study design and methods: 65 Patients requiring all first premolar extractions were randomly allocated to three groups. Two groups (Comprising of passive self-ligating brackets and conventional brackets) were treated with LLLT and one group served as the control (conventional brackets). The allocation ratio was 1:1:1.32. Eligibility criteria: adolescent patients with sound and healthy permanent dentition with Little's Irregularity Index<5mm.

MAIN OUTCOME

rate of tooth movement in mm/month. Randomization and blinding: computer-generated random allocation sequence; only the data analyser was blinded by coding the digital models. Patients were reviewed once every month till the completion of space closure.

STATISTICS

data normality was checked using Shapiro-Wilks test and Q-Q Plot. Parametric tests were applied for the inferential statistics (ANCOVA) with Dunnett's t test being used for post hoc analysis.

RESULTS

There was a statistically significant enhancement in the rate of OTM in the 2 experimental groups (0.68/0.67mm/month in the right and left side of the maxilla and 0.66/0.65mm/month in the right and left side of the mandible) when compared with the control group (0.48mm/month in the maxilla and 0.48mm/month in the mandible) (P<0.05), but when the 2 experimental groups were compared no difference was observed (P>0.05). No serious harms were reported.

CONCLUSION

A significant increase in the rate of OTM was observed with the application of LLLT. No difference was observed in the rate of OTM when comparing different ligation methods treated with LLLT.

REGISTRATION

National Trial Registry (CTRI No- CTRI/2018/04/013156). Protocol was not published before trial commencement.

Evaluation of the effects of vitamins C and E on experimental orthodontic tooth movement

Background. This experimental study aimed to assess the effects of Vitamins C and E on orthodontic tooth movement.

Methods. Fifty-one male Wistar albino rats were divided into six groups: five appliance groups and one control group. The appliance groups had an orthodontic appliance consisting of a closed-coil spring ligated between the maxillary incisor and maxillary first molar (50 g). Vitamin E and C (150 mg/kg) were injected intraperitoneally per day in the first and second groups, respectively. Vitamins E and C (20 μL) were locally injected into the periodontal gap of the moving teeth in the third and fourth groups, respectively, once every three days. No vitamin was injected in the last (fifth) appliance group.The experimental period was 18 days. Histological and biochemical (alkaline phosphatase, osteocalcin, and NTx levels) evaluations of the samples were performed, and maxillary incisor‒molar distance was measured before and after the experiment.

Results. The amount of tooth movement was similar in the appliance groups. All the vitamin groups showed significantly increased osteoblastic activity, while those treated with systemic vitamins exhibited significantly increased numbers of collagen fibers on the tension side compared to the appliance control group (P<0.05).

Conclusion. Vitamin C and E supplements positively affected bone formation on the tension side of the teeth during experimental orthodontic tooth movement.

Use of Laser Systems in Orthodontics

Laser systems have been used in the practice of dentistry for >35 years. Laser systems have so many advantages, such as increase patient cooperation, reduce the duration of treatment time, and help the orthodontists to enhance the design of a patient's smile to improve treatment efficacy, and the success of orthodontic treatments can also be improved by diminishing the orthodontic pain and the discomfort of the patients. Laser systems also have some disadvantages, such as cost, large space requirements for some types, and high-risk potential for physician and patient if not used at the appropriate wavelength and power density, that is why before incorporating lasers into clinical practice, the physician must fully understand the basic science, safety protocol, and risks associated with them. Lasers have many applications in orthodontics, including accelerating tooth movement, bonding and debonding processes, pain reduction, bone regeneration, etching procedures, increase mini-implant stability, soft tissue procedures (gingivectomy, frenectomy, operculectomy, papilla flattening, uncovering temporary anchorage devices, ablation of aphthous ulcerations, and exposure of impacted teeth), fiberotomy, scanning systems, and welding procedures. In reviewing the literature on the use of laser in orthodontics, many studies have been conducted. The purpose of the present study was to give information about the use of laser in the field of orthodontics, the effects of laser during the postoperative period, and its advantages and disadvantages and to provide general information about the requirements to be considered during the use of laser.

Photobiomodulation Therapy on Orthodontic Movement: Analysis of Preliminary Studies with a New Protocol

This study aimed to investigate the effectiveness of photobiomodulation therapy (PBMT) on the acceleration of orthodontic movements, deriving from its biostimulating and regenerative capacity on soft tissues, consequent to the increase in differentiation, proliferation, and activity of cells that are involved with alveolar bone remodeling. The present randomized controlled trial was conducted on six patients who required extractive orthodontic therapy because their ectopic canines had erupted. A total of eight canines were analyzed, four of which received laser irradiation (i.e., experimental group). Two weeks after the extractions, all canines of the experimental and placebo groups were distalized simultaneously and symmetrically with the laceback retraction technique. The PBMT protocol consisted of four cycles of laser applications, one each on days 0, 3, 7, and 14 of the study, with session treatment durations of 2–4 min. The results of the descriptive analysis on the distal displacement speed of the canines after 1 month of follow-up indicate an average displacement of 1.35 mm for the non-irradiated group and 1.98 mm for the irradiated group. Through inferential analysis, a statistically significant difference (p < 0.05) was found between the average speed of the irradiated canines and the control canines. The low energy density laser used in this study, with the parameters set, was found to be a tool capable of statistically significantly accelerating the distal displacement of canines.

Baicalin inhibits root resorption during tooth movement in a rodent model

OBJECTIVE

Baicalin mediates bone metabolism and has shown protective activity against periodontal tissue damage in a rat model of periodontitis. Therefore, we hypothesized that baicalin may inhibit the root resorption that occurs during orthodontic tooth movement and examined its effect on the histological changes in periodontal tissue that occur during tooth movement.

METHODS

First molars of rats were subjected to traction using excessive orthodontic force to produce a root resorption model. Rats in the baicalin group received baicalin for 3 weeks during tooth movement, and the amount of first molar movement on day 21 after the initiation of traction was measured by three-dimensional micro-computed tomography analysis. 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 tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical staining for the receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG). The severity of root resorption was also determined by histological analysis.

RESULTS

There was no significant intergroup difference in tooth movement during the experimental exaggerated tooth movement. In comparison with the control group, the baicalin-treated group showed increased OPG expression, suppressed RANKL expression, and significantly fewer TRAP-positive cells in the first molars. The root resorption area was significantly smaller in the baicalin group.

CONCLUSIONS

Treatment with baicalin prevented root resorption without preventing tooth movement. Baicalin may be useful for the management of root resorption during orthodontic treatment.

The effect of low-level laser radiation and doxycycline on the levels of osteoprotegerin and receptor activator of nuclear factor kappa-B ligand

The present in vitro study was conducted to investigate the effect of low-level laser (LLL) radiation and doxycycline on the levels of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) derived from MG-63 osteosarcoma cell line. MG-63 cells were divided into four groups. In the first group, 2 mg/mL of doxycycline was injected into the cell culture medium. Diode laser (810 nm, 100 mw, 75 s) was radiated to the culture medium of the second group. The third group received both doxycycline and laser radiation. In the fourth group (control), the culture medium was replaced daily, similar to the above three groups. Mentioned interventions were performed once a day for 4 consecutive days. Then, on the sixth day, the levels of OPG and RANKL mediators were measured using real-time polymerase chain reaction by isolating the cells from the samples. OPG expression had the highest to lowest levels in the laser + doxycycline, doxycycline, laser, and control groups, respectively. The level of OPG was significantly different between all the study groups (p < 0.05) except in the doxycycline + laser and doxycycline groups (p = 0.061). The highest to lowest levels of RANKL was observed in the doxycycline, laser + doxycycline, control, and laser groups, respectively. The RANKL expression was not significantly different between all the study groups (p > 0.05). The results of this study revealed that LLL and doxycycline reduced the RANKL/OPG ratio derived from the MG-63 osteosarcoma cell line, which may result in the diminished activity of osteoclasts and osteoclastogenesis.

The Effect of Low-Level Laser Therapy on the Acceleration of Orthodontic Tooth Movement

In clinical practice, low-level laser therapy (LLLT) is widely used. The main aim of this review is to assess the effectiveness of LLLT in accelerating tooth movement in human subjects. The PRISMA checklist was utilized as a guideline to carry out this systematic review. The electronic databases were searched from Google Scholar (2014-2018) and PubMed, and comprehensive research on this topic was also manually conducted. Therefore, 77 articles randomized clinical trials (RCTs) or controlled clinical trials (CCTs) were selected. After screening studies, consequently, eleven trials met the inclusion criteria. Eight out of 11 studies showed LLLT has a significant impact on the acceleration of orthodontic tooth movement, and there was no statistically significant difference in the rate of tooth movement between the laser group and the control group in the two remaining studies. Furthermore, five out of 11 articles showed that LLLT has no adverse effects. Although we have some degree of understanding from a cellular point of view to LLLT effects, we still do not know whether these cellular level changes have any effect on the clinical acceleration of orthodontic tooth movement. The results are inconclusive and cannot be generalized to the public community; therefore, well-structured studies are required.

A Comparative Assessment of the Efficiency of Orthodontic Treatment With and Without Photobiomodulation During Mandibular Decrowding in Young Subjects: A Single-Center, Single-Blind Randomized Controlled Trial

Objective: To assess if photobiomodulation (PBM) improves the efficiency of orthodontic treatment with fixed appliance during the alignment stage.

Methods: Eighty-nine subjects were included in this trial and randomly assigned for treatment with fixed appliance and PBM group or with fixed appliance only (control group). Inclusion criteria were as follows: (1) age between 13 and 30 years, (2) permanent dentition, (3) class I malocclusion, (4) lower 6–6 mild crowding measured on dental cast, (5) no spaces or diastema in the lower arch, (6) no ectopic teeth, (7) nonextractive treatment plan, and (8) no previous orthodontic treatment. PBM was administered in the PBM group every 14 days using the ATP38^® (Biotech Dental, Allée de Craponne, Salon de Provence, France) (72 J/cm² of fluency for each session). Dental alignment was assessed by visual inspection, and treatment time was defined in days as T2 (date of assessment of complete dental alignment)–T1 (date of brackets bonding). The number of monthly scheduled appointments was also recorded. All the data underwent statistical analysis for comparison between groups.

Results: Treatment time was significantly shorter (p < 0.001) in the PBM group (203 days) compared with the control (260 days). Consequently, control visits (p < 0.001) were lower in the PBM group (7) compared with the control group (9).

Conclusions: The present findings would confirm that PBM can be used to enhance the efficiency of orthodontic treatment during dental decrowding.

The effect of combined corticotomy and low level laser therapy on the rate of orthodontic tooth movement: split mouth randomized clinical trial

Purpose

The aim of this study was to evaluate the combined effect of corticotomy and Low-Level Laser Therapy(LLLT) on the rate of orthodontic tooth movement.

Methods

A randomized split-mouth design for 16 female patients compared the rate of maxillary canine retraction using corticotomy combined with LLLT versus corticotomy only. The device used in the present study was an In-Ga-As semiconductor diode laser emitting at 940 nm (IR) with these parameters: 0.5 W/ cm² power density, 5 J/cm² Fluence, CW, 240 sec time irradiation, weekly for the first month and twice monthly for the next three months. Assessment of the rate of canine retraction was carried out via a series of dental models.

Results

A non-significant statistical rate of canine retraction was achieved by LLLT combined to corticotomy compared with the corticotomy technique alone.

Conclusion

Low-Level Laser Therapy combined to corticotomy could not achieve a higher rate of canine retraction compared to the golden standard corticotomy technique alone. No long-term adverse effects on the alveolar mucosa were detected following both techniques.

The Effect of Photobiomodulation on Distraction Osteogenesis

Distraction osteogenesis (DO) is a surgical procedure to increase bone height in different body parts. DO includes a surgical incision, wherein the bone is cut and a device is installed for further separation of the two ends by gradual unscrewing of the device screw. New bone gradually forms and fills the gap, and the bone height increases as such. Photobiomodulation (PBM) or low-level laser therapy (LLLT) enhances the formation of soft and hard tissue such as bone and can, therefore, accelerate the process of DO and shorten the duration of different surgical phases of DO such as latency, activation, and consolidation. Different laser types with variable exposure settings and protocols have been used for this purpose. The gallium-aluminum-arsenide (GaAlAs) diode laser is the most commonly used laser type for LLLT. This study reviews 18 published articles on the effects of LLLT on DO and summarizes their findings to further elucidate this topic.

Comparison of the efficiency of alveolar decortication and low level laser therapy on orthodontic tooth movement and alveolar metabolism in rats

Background/purpose

Reducing orthodontic treatment duration has many advantages for both clinicians and patients. This study was designed to compare the effects of alveolar decortication and low level laser therapy methods on tooth movement rate and alveolar bone metabolism.

Materials and methods

A total of 42 Wistar albino rats were divided into three main groups as: Alveolar decortication (AD), low level laser therapy (LLLT) and only orthodontic force (F). The groups were evaluated at 7 and 14 day time points. Tooth movement rates were calculated by measuring the space between the contact points of the first and second molars. Comparisons regarding the alveolar bone metabolism were accomplished by evaluating osteoclast counts and RANKL - OPG expressions.

Results

The rate of tooth movement, at all time points, was significantly higher for the AD group than the other groups and was significantly higher in the LLLT group than the F group. At both time points, the RANKL and OPG expression in the AD group was significantly higher than the other groups and these parameters in the LLLT group was significantly higher than the F group. The osteoclast count values in the AD and LLLT groups were significantly higher than the F group and there were no significant differences between these two groups at all time points.

Conclusion

This study shows that, to be more effective at AD, both AD and LLLT therapy significantly increases the level of tooth movement in the early period through their stimulating effects on the alveolar bone metabolism.