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

OBJECTIVE: This systematic review aimed to establish an effective wavelength range for PhotoBioModulation (PBM) to relieve pain in orthodontic treatments. MATERIAL AND METHODS: The electronic literature search was carried out in the following databases: PubMed, ISI Web of Science, Scopus, and Cochrane. In the initial search, 255 papers were obtained. Deleting duplicates in the search left 180 items. One manually searched study was included for a total of 181 studies. According to PRISMA guidelines and a thorough analysis of their methodology, the final sample was composed of 13 RCTs. The final statistical analysis was performed in 11 studies. The statistical analysis sought to strengthen the collected data, determining the correlation coefficient (r) for the same time interval (24h) using a scale equivalent to the standard value (0-10cm). Aiming to reduce the effect of heterogeneity, the difference in cm between control group (GC) and experimental group (EG) averages was considered the outcome. This difference was correlated with the wavelength in nm, calculating the Pearson linear correlation coefficient, and calculating a logarithmic correlation. RESULTS: The dispersion of the data obtained in the experimental groups at each given wavelength showed that the most significant number of studies were in the ranges of 780-830nm. The correlation between the wavelength and the difference between the control and experimental group averages, either linear (R2=0.0564, r=0.237) or logarithmic (R2=0.0688, r=0.262) was not significant (P>0.90). Therefore, pain reduction after 24h is not significantly dependent of wavelength. CONCLUSION: The majority of RCTs related to pain relief in orthodontic treatment showed 780-830nm as the most effective photobiomodulation wavelength range for orthodontic pain relief. However, pain reduction after 24h is not significantly dependent of wavelength. The protocol was registered in PROSPERO (CRD42019119799).

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

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

Photobiomodulation as oedema adjuvant in post-orthognathic surgery patients: A randomized clinical trial.

OBJECTIVE: Photobiomodulation therapy (PBMT) has been used in multiple applications in general medicine as powerful anti-inflammatory, analgesic and reducing oedema in different parts of the body. The aim of this study is to compare the effect on post-surgical oedema after mandibular orthognathic surgery, between two different laser power densities and oral medication with non-steroidal anti-inflammatory. MATERIALS AND METHODS: In a randomized clinical trial, on 60 patients who were subject to mandibular orthognathic surgery were divided into three groups. All groups received sodium naproxen 250mg every 8hours for 6days. Two groups were irradiated with two different laser application protocols and the other was a control group. In G1 group the irradiation parameters three times per week for two weeks were: 940nm, in continuous mode, 2.5W, 120s, 85.71J/cm2, 0.89W/cm2, over the right and left side with a distance from the skin surface of 1mm with the whitening handpiece (spot size of 2.8cm2). In G2, the irradiation parameters three times a week for two weeks were: 940nm, in continuous mode, 4.1W, 120s, 68.33J/cm2, 0.58W/cm2 over the right and left side with a distance from the skin surface of 15mm, with the deep tissue handpiece (spot size of 7.1cm2). In all the groups, millimetric facial measurements were taken from tragus to lateral commissure, and from lateral commissure to gonion in both sides. RESULTS: All differences between T1 and T6 were significant for the three groups, (paired T, P<0.05). The differences between the groups were generally not significant (P>0.05) except for commissure - right and left gonion when compared G1 vs CG (P<0.05) and G2 vs CG (P<0.05). Initial changes (T1-T2) between groups were significantly different except for the measurement from commissure to right tragus G1 vs CG (P=0.411) and from commissure to left tragus G2 vs CG (P=0.94). The faster resolution of the oedema occurred in G2 group. PTBM with an energy density of 68.33J/cm2 was the most effective adjuvant to oral medication with non-steroidal anti-inflammatory, to decrease post-surgical oedema after mandibular orthognathic surgery.

Reevaluation of the Strain Pressure Theory: Toward a Better Understanding the Biology of Tooth Movement / Reevaluación de la Teoría Presión - Tensión: Hacia una Mejor Comprensión de la Biología del Movimiento Dental

The aim of this report was to analyze the majority of publications referred to orthodontic movement Biological basis, principally strain- pressure theory taking account contemporaneous methodological study designs. The literature published in Pubmed from 1967 to 2014 was reviewed, in addition to well-known scientific reports that were not classified under this database like classical manuscripts since 1839. The comment items are: Limitations of animal models, Histological slices, what to watch for, Rats as an experimental model in orthodontics, Strain­pressure, the force used in these studies that fundament this theory, Reevaluation studies about strain-pressure theory in biology movement using contemporaneous models, Up to date concepts, Theory reevaluation the first step to understanding new acceleration concepts and Movement biology research, present and future. After analyzing those items we concluded: A 3D perspective is essential for a complete understanding of events in tooth movement involves two interrelated processes: the bending of alveolar bone and remodeling of the periodontal tissues. It's important to start, and acknowledge that the PDL cannot be divided into two different areas that react independently to an applied force. It´s a continuous periodontal compartment in OTM, rather than a pressure side and a tension side. When an orthodontic force is applied there are two simultaneous effects that correlate. Alveolar bone flexion and remodeling of the periodontal tissues. Alveolar Bone deformation compromising the main structures (PDL, bone and cement), compression and tension can coexist in different directions. The magnitudes of compression and tension are typically different in different directions. As the majority of research and studies indicate that fundamental movement biology are made on animal models, it is important to know that their results and conclusions, under the actual evidenced based practice guidelines do not allow to make clinical decisions even if they are included on systematic reviews.

El objetivo de esta revisión es analizar la mayoría de las publicaciones relacionadas a la fundamentación sobre el movimiento de ortodoncia, principalmente la teoría presión-tensión, teniendo en cuenta los diseños de estudios metodológicos contemporáneos. Se revisó la literatura publicada en la base de datos de MEDLINE, 1967-2013 , además de los informes conocidos que no fueron clasificados en esta base de datos como manuscritos clásicos desde 1839. Los temas principales en los que se divide el artículo son: Limitaciones de los modelos animales, cortes histológicos, las ratas como modelo experimental en ortodoncia, la fuerza utilizada en los estudios que fundamentan esta teoría, reevaluación sobre los estudios de la teoría presión ­tensión en modelos contemporáneos, conceptos actuales en biología del movimiento, reevaluación de la teoría: el primer paso para entender los nuevos métodos en aceleración del movimiento, conceptos e investigaciones en biología del movimiento: presente y futuro. Una perspectiva 3D es esencial para una comprensión completa de los acontecimientos. El movimiento dental implica dos procesos interrelacionados: la curvatura del hueso alveolar y la remodelación de los tejidos periodontales. Es importante empezar, y reconocer que el PDL no puede ser dividido en dos áreas diferentes que reaccionan de forma independiente a una fuerza aplicada. Está en un compartimiento continuo periodontal , en lugar de un lado de presión y un lado de tensión. Al aplicar una fuerza de ortodoncia hay dos efectos simultáneos: la flexión del hueso Alveolar y la remodelación de los tejidos periodontales. La deformación del hueso compromete las estructuras principales (PDL, hueso y cemento) y la compresión y la tensión pueden coexistir en diferentes direcciones.